Minimum Clinically Important Difference and Patient Acceptable Symptom State of Japanese Orthopaedic Association Score in Degenerative Cervical Myelopathy Patients

Prevalence of idiopathic normal pressure hydrocephalus in patients with degenerative cervical myelopathy

PURPOSE

Degenerative cervical myelopathy (DCM) and idiopathic normal pressure hydrocephalus (iNPH) share symptoms such as gait disturbance and urinary dysfunction, especially in the elderly. While the incidence of DCM in patients with iNPH is reported, the prevalence of iNPH in patients with DCM remains unclear. This study investigates the prevalence of iNPH in DCM patients.

METHODS

This retrospective cohort study included 83 patients undergoing decompression surgery for DCM between April 2018 and March 2023. Brain MRI performed within three years prior to surgery was analyzed. Patients were categorized into two groups based on the Evans Index (EI): those with EI > 0.3 were classified as the Suspected-iNPH group, and those with EI ≤ 0.3 as the Non-iNPH group. Pre- and postoperative Japanese Orthopedic Association (JOA) scores and Patient-Reported Outcomes (PROs), including the Neck Disability Index (NDI), EuroQOL-5D (EQ-5D), Core Outcome Measure Index (COMI), and Numerical Rating Scale (NRS) for pain, were compared. Suspected-iNPH cases underwent further analysis to identify disproportionately enlarged subarachnoid space hydrocephalus (DESH).

RESULTS

Thirty-one patients (37%) were classified as Suspected-iNPH, who were significantly older (p = 0.01). No significant differences were found in pre- or postoperative JOA scores, and PROs. DESH was identified in 6 patients (7%), with 2 diagnosed as probable-iNPH based on cerebrospinal fluid tap tests.

CONCLUSIONS

A notable proportion of elderly DCM patients exhibit ventricular enlargement and DESH, suggesting a potential overlap with iNPH. Brain MRI should be considered for elderly DCM patients, particularly when neurological symptoms deviate from typical patterns.

Spinal Cord Status Assessment and Early Interventional Personalized Rehabilitation after Endoscopic Surgery for Cervical Compressive Myelopathy: A Randomized Trial

BACKGROUND CONTEXT

Cervical compressive myelopathy (CCM), frequently arising from spinal degeneration, results in significant motor and sensory deficits. Currently, there is a lack of precise prognostic evaluation methods following decompression surgery for CCM, which hinders the optimization of personalized rehabilitation therapy. However, the combination of intraoperative endoscopic visualization of dural sac compression morphology and electrophysiological functional assessment holds promise in addressing this gap.

PURPOSE

To determine whether a personalized rehabilitation strategy, informed by intraoperative endoscopic and electrophysiological assessments, enhances postoperative functional outcomes in CCM patients compared to traditional rehabilitation after canal decompression surgery.

STUDY DESIGN/SETTING

PROSPECTIVE SINGLE-CENTER RANDOMIZED CONTROLLED STUDY, TRIAL REGISTRATION: ChiCTR2400081458.

PATIENT SAMPLE

78 patients underwent spinal decompression surgery at The Sixth Medical Center of Chinese PLA General Hospital. The inclusion criteria included a diagnosis of CCM due to spondylosis or ossification of the longitudinal ligament. Participants were excluded if they had prior spinal surgeries or comorbidities unrelated to CCM.

OUTCOME MEASURES

The primary outcome was the Japanese Orthopaedic Association (JOA) score, assessing spinal function. Secondary outcomes included the Neck Disability Index (NDI), Visual Analogue Scale (VAS) for pain, and three-dimensional gait analysis.

METHODS

This study was a double-blind randomized controlled trial comparing two postoperative rehabilitation strategies for patients with CCM following endoscopic spinal decompression surgery. After surgery, patients were randomly assigned to two groups. The experimental group received personalized rehabilitation based on real-time intraoperative spinal cord status assessments, using a combination of endoscopic visualization and electrophysiological grading. Interventions included lower limb exoskeleton-assisted walking and targeted motor function training. The control group received conventional standard rehabilitation treatment. Both groups were assessed using the JOA, NDI, and VAS scores before rehabilitation, 1 month, 3 months, and 12 months after the start of rehabilitation. Additionally, gait analysis (including stride frequency, gait velocity, and stride length) was performed before and 3 months after the start of rehabilitation to evaluate the clinical rehabilitation outcomes in both groups.

RESULTS

Both groups showed significant improvements in JOA, NDI, VAS scores, and gait tests during the postoperative rehabilitation process. The experimental group demonstrated a more substantial increase in the primary outcome measure, the JOA score (12MO: 4.79±0.74 vs 3.53±0.93, P < 0.05). Additionally, the experimental group exhibited notable improvements in both stride frequency and gait velocity (3MO: Stride frequency (3.76±0.23 vs 1.05±0.07) and Gait velocity (4.53±0.63 vs 4.21±0.43), P < 0.05).

CONCLUSIONS

The spinal cord status assessment methods based on spinal endoscopy and electrophysiological techniques can effectively evaluate the condition of the spinal cord. When combined with personalized rehabilitation strategies tailored to these assessments, they can significantly enhance the postoperative spinal cord function recovery in CCM patients, providing superior clinical rehabilitation outcomes compared to traditional rehabilitation methods.

K-Line Tilt May Influence the Short-Term Surgical Outcomes After Laminoplasty in Patients With Degenerative Cervical Myelopathy

Study DesignA retrospective study.ObjectivesTo explore the relationship between K-line tilt and short-term surgical outcomes following laminoplasty in patients with multilevel degenerative cervical myelopathy (DCM), and to evaluate the potential of K-line tilt as a reliable preoperative predictor.MethodsA retrospective analysis was performed for 125 consecutive patients who underwent laminoplasty for multilevel DCM. The radiographic parameters utilized in this study encompassed T1 slope (T1S), C2-C7 lordosis (CL), C2-C7 sagittal vertical axis (cSVA), T1 slope minus C2-C7 lordosis (T1S-CL), C2-C7 range of motion (ROM), and K-line tilt. The neurological recovery was evaluated using the Japanese Orthopaedic Association (JOA) score. Pearson correlation coefficients were calculated to assess the relationship between K-line tilt and other classical cervical parameters. Logistic regression analysis was employed to examine the association between K-line tilt and surgical outcomes.ResultsOf the 125 patients, 89 were men. The mean age of the patients was 61.74 ± 11.31 years. The results indicated a correlation between the K-line tilt and the cSVA (r = 0.628, P < 0.001), T1S (r = 0.259, P = 0.004), and T1S-CL (r = 0.307, P < 0.001). The K-line tilt showed an association with the failure of the JOA recovery rate (RR) to reach the minimal clinically important difference (MCID) and the occurrence of postoperative kyphotic deformity. We identified cutoff values for the K-line tilt which predict the failure of the JOA RR to reach the MCID and postoperative kyphotic deformity as 10.13° and 9.93°, respectively.ConclusionsThe K-line tilt is an independent preoperative risk factor associated with both the failure of the JOA RR to reach the MCID and the occurrence of postoperative kyphotic deformity in patients with multilevel DCM after laminoplasty.

Development of a Dual-Plane MRI-Based Deep Learning Model to Assess the 1-Year Postoperative Outcomes in Lumbar Disc Herniation After Tubular Microdiscectomy

BACKGROUND

Tubular microdiscectomy (TMD) is a treatment for lumbar disc herniation (LDH). Although the combination of MRI and deep learning (DL) has shown promise, its application in evaluating postoperative outcomes in TMD has not been fully explored.

PURPOSE/HYPOTHESIS

To evaluate whether integrating preoperative dual-plane MRI-based DL features with clinical features can assess 1-year outcomes in TMD for LDH.

STUDY TYPE

Retrospective.

POPULATION/SUBJECTS

The study involved 548 patients who underwent TMD between January 2016 and January 2021. Training set (N = 305, mean age 51.85 ± 13.84 years, 56.4% male). Internal validation set (N = 131, mean age 51.85 ± 13.84 years, 54.2% male). External validation set (N = 112, mean age 51.54 ± 14.43 years, 50.9% male).

FIELD STRENGTH/SEQUENCE

3 T MRI with sagittal and transverse T2-weighted sequences (Fast Spin Echo).

ASSESSMENT

Ground truth labels were based on improvement rate in 1-year Japanese Orthopaedic Association (JOA) scores. Information on 42 preoperative clinical features was collected. The largest protrusions were identified from T2 MRI by three clinicians and were used to train deep learning models (ResNet50, ResNet101, and ResNet152) to extract DL features. After feature selection, three models were built, namely, clinical, DL, and combined models.

STATISTICAL TESTS

Chi-square or Fisher's exact tests was used for group comparisons. Quantitative differences were analyzed using the t-test or Mann-Whitney U test. P-values <0.05 were considered significant. Models were validated on internal and external datasets using metrics such as the area under the curve (AUC).

RESULTS

The AUCs of the clinical models achieved 0.806 (internal) and 0.779 (external). ResNet152 performed best in three DL models, with AUCs of 0.858 (internal) and 0.834 (external). The combined model achieved AUCs of 0.889 (internal) and 0.857 (external).

DATA CONCLUSION

A model combining preoperative dual-plane MRI DL features and clinical features can assess 1-year outcomes of TMD for LDH.

EVIDENCE LEVEL

4 TECHNICAL EFFICACY: Stage 2.

Despite a Multifactorial Etiology, Rates of Distal Junctional Kyphosis After Adult Cervical Deformity Corrective Surgery Can be Dramatically Diminished by Optimizing Age Specific Radiographic Improvement

Study DesignRetrospective cohort study of a prospectively collected single-center database.ObjectiveDistal Junctional Kyphosis (DJK) is one of the most common complications in adult cervical deformity (ACD) correction. The utility of radiographic alignment alone in predicting and minimizing DJK occurrence warrants further study. To investigate the impact of post-operative radiographic alignment on development of DJK in ACD patients.MethodsACD patients (≥18 yrs) with complete baseline (BL) and two-year (2Y) radiographic data were included. DJF was defined as DJK greater than 15° (Passias et al) or DJK with reop. Multivariable logistic regression (MVA) identified 3-month predictors of DJK. Conditional inference tree (CIT) machine learning analysis determined threshold cutoffs. Radiographic predictors were combined in a model to determine predictive value using area under the curve (AUC) methodology. "Match" refers to ideal age-adjusted alignment.Results140 cervical deformity patients met inclusion criteria (61.3 yrs, 67% F, BMI: 29 kg/m2, CCI: 0.96 ± 1.3). Surgically, 51.3% had osteotomies, 47.1% had a posterior approach, 34.5% combined approach, 18.5% anterior approach, with an average 7.6 ± 3.8 levels fused and EBL of 824 mL. Overall, 33 patients (23.6%) developed DJK, and 11 patients (9%) developed DJF. MVA controlling for age, and baseline deformity, followed by CIT found 3M cSVA <3.7 cm (OR: .2, 95% CI:.06-.6), and TK T4-T12 <50 (OR:.17, 95% CI:.05-.5, both P < .05) were significant predictors of a lower likelihood of DJK. Receiver operator curve AUC using age, T1S match, TS-CL match, LL-TK match, cSVA <3.7 cm, and T4-T12 <50 predicted DJK with an AUC of .91 for DJK by 2Y, and .88 for DJF by 2Y.ConclusionThese findings suggest post-operative radiographic alignment is strongly associated with distal junctional kyphosis. When utilizing age-adjusted realignment in addition to newly developed thresholds, a suggested post-operative cSVA target of 3.7 cm and thoracic kyphosis less than 50, it is possible to substantially reduce the occurrence of distal junctional kyphosis and distal junctional failure.

Preoperative Disability Influences Effectiveness of Minimal Clinically Important Difference and Patient Acceptable Symptom State in Predicting Patient Improvement Following Cervical Spine Surgery

STUDY DESIGN

Retrospective cohort.

OBJECTIVE

To compare the characteristics of the minimal clinically important difference (MCID) and patient acceptable symptom state (PASS) metrics when interpreting Neck Disability Index (NDI) following cervical spine surgery.

METHODS

Patients who underwent primary cervical fusion, discectomy, or laminectomy were included. NDI and global rating change (GRC) data at 6 months/1 year/2 years were analyzed. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of MCID and PASS in predicting improvement on GRC were calculated for the overall cohort and separately for patients with minimal (NDI <30), moderate (NDI 30 - 49), and severe (NDI ≥ 50) preoperative disability. Two groups with patients who achieved PASS but not MCID and patients who achieved MCID but not PASS were analyzed.

RESULTS

141 patients (206 responses) were included. PASS had significantly greater sensitivity for the overall cohort (85% vs 73% with MCID, P = .02) and patients with minimal disability (96% vs 53% with MCID, P < .001). MCID had greater sensitivity for patients with severe disability (78% vs 57% with PASS, P = .05). Sensitivity was not significantly different for PASS and MCID in patients with moderate preoperative disability (83% vs 92%, P = .1). 17% of patients achieved PASS but not MCID and 9% of patients achieved MCID but not PASS. Most of these patients still reported improvement with no significant difference between the 2 groups (89% vs 72%, P = .13).

CONCLUSION

PASS and MCID are better metrics for patients with minimal and severe preoperative disability, respectively. Both metrics are equally effective for patients with moderate preoperative disability.

Open-Door Cervical Laminoplasty Using Instrumentation of Every Level Versus Alternate Levels: A Multicenter, Randomized Controlled Trial

BACKGROUND

In the setting of cervical open-door laminoplasty, the question of whether or not every opened laminar level should be instrumented has not been sufficiently investigated. We postulated that the surgical outcomes of open-door laminoplasty with instrumentation of every second opened level (skip-fixation) might not be inferior to those of laminoplasty with instrumentation of every opened level (all-fixation). The purpose of the present study was to test the noninferiority of laminoplasty with skip-fixation in improving myelopathy at 2 years postoperatively compared with all-fixation. Additionally, we compared radiographic and surgical outcomes between the 2 types of procedures.

METHODS

This prospective, multicenter, unblinded randomized controlled trial included patients ≥60 years of age who underwent C3 to C6 open-door cervical laminoplasty for the treatment of degenerative cervical myelopathy. Patients were allocated to the skip-fixation group (n = 80) or the all-fixation group (n = 75) using a permuted block method. The primary outcome was the between-group difference in the Japanese Orthopaedic Association (JOA) score at 2 years postoperatively. Secondary outcomes included surgical data, complications, 2-year change in the JOA score, Neck Disability Index (NDI), EQ-5D-5L (EuroQol 5-dimension 5-level instrument) score, visual analog scale (VAS) score for neck pain, and radiographic outcomes.

RESULTS

One hundred and thirty patients (including 66 in the skip-fixation group and 64 in the all-fixation group) completed the trial at 2 years (follow-up rate, 83.9%). The difference in the JOA score at 2 years was 0.0298 (95% confidence interval [CI], -0.706 to 0.766), which was within the noninferiority margin (p < 0.0001; noninferiority test). In the secondary analyses, laminoplasty with skip-fixation demonstrated a significantly shorter surgical time (p = 0.010; Mann-Whitney U test) and greater improvement in the VAS score for neck pain, NDI, and EQ-5D-5L score (p = 0.006, p = 0.047, p = 0.037, respectively; mixed-effect model) compared with all-fixation. There were no significant between-group differences in radiographic outcomes, including the hinge union rate.

CONCLUSIONS

Skip-fixation may be sufficient to achieve noninferior 2-year postoperative improvement in myelopathy. Additionally, laminoplasty with skip-fixation potentially can lead to improvements in terms of neck pain, neck disability, and quality of life compared with all-fixation.

LEVEL OF EVIDENCE

Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.

Multimodal Deep Learning-based Radiomics Approach for Predicting Surgical Outcomes in Patients with Cervical Ossification of the Posterior Longitudinal Ligament

STUDY DESIGN

A retrospective analysis.

OBJECTIVE

This research sought to develop a predictive model for surgical outcomes in patients with cervical ossification of the posterior longitudinal ligament (OPLL) using deep learning and machine learning (ML) techniques.

SUMMARY OF BACKGROUND DATA

Determining surgical outcomes assists surgeons in communicating prognosis to patients and setting their expectations. Deep learning and ML are computational models that identify patterns from large data sets and make predictions.

METHODS

Of the 482 patients, 288 patients were included in the analysis. A minimal clinically important difference (MCID) was defined as gain in Japanese Orthopaedic Association (JOA) score of 2.5 points or more. The predictive model for MCID achievement at 1 year postsurgery was constructed using patient background, clinical symptoms, and preoperative imaging features (x-ray, CT, MRI) analyzed through LightGBM and deep learning with RadImagenet.

RESULTS

The median preoperative JOA score was 11.0 (IQR: 9.0-12.0), which significantly improved to 14.0 (IQR: 12.0-15.0) at 1 year after surgery ( P < 0.001, Wilcoxon signed-rank test). The average improvement rate of the JOA score was 44.7%, and 60.1% of patients achieved the MCID. Our model exhibited an area under the receiver operating characteristic curve of 0.81 and the accuracy of 71.9% in predicting MCID at 1 year. Preoperative JOA score and certain preoperative imaging features were identified as the most significant factors in the predictive models.

CONCLUSION

A predictive ML and deep learning model for surgical outcomes in OPLL patients is feasible, suggesting promising applications in spinal surgery.

LEVEL OF EVIDENCE

4.

White matter spinal tracts impairment in patients with degenerative cervical myelopathy evaluated with the magnetization transfer saturation MRI technique

STUDY DESIGN

Prospective case-control study.

OBJECTIVES

We investigated the use of the magnetization transfer saturation (MTsat) technique to assess the structural integrity of the spinal cord tracts in individuals with clinically significant degenerative cervical myelopathy (DCM) and associated disability.

SETTING

Novosibirsk Neurosurgery Centre, Russia.

METHODS

A total of 53 individuals diagnosed with DCM and 41 patients with cervical radiculopathy underwent high-resolution MRI of the cervical spinal cord via the magnetization transfer technique. The MRI data were processed using the Spinal Cord Toolbox (v5.5), with MTsat values determined for each spinal tract and compared between the two groups. Furthermore, associations between MTsat values and the clinical disability rates of patients were investigated.

RESULTS

A significant decrease in the MTsat of the ventral spinocerebellar tract was observed in the DCM group compared to the control group (adjusted p < 0.001). There was a trend towards lower MTsat values in the rubrospinal tract in the DCM group (adjusted p = 0.08). Additionally, a decrease in MTsat values in the lateral funiculi of the spinal cord was found in patients with DCM (adjusted p < 0.01). Furthermore, a trend toward a positive correlation was observed between the JOA score and the MTsat values within the ventral spinocerebellar tract (R = 0.33, adjusted p = 0.051).

CONCLUSIONS

The findings of our study indicate that demyelination in patients with DCM affects mainly the ventral spinocerebellar and rubrospinal tracts, and the extent of changes in the ventral spinocerebellar tract is related to the severity of the condition.

Focal compression of the cervical spinal cord alone does not indicate high risk of neurological deterioration in patients with a diagnosis of mild degenerative cervical myelopathy

Degenerative Cervical Myelopathy (DCM) is the functional derangement of the spinal cord resulting from vertebral column spondylotic degeneration. Typical neurological symptoms of DCM include gait imbalance, hand/arm numbness, and upper extremity dexterity loss. Greater spinal cord compression is believed to lead to a higher rate of neurological deterioration, although clinical experience suggests a more complex mechanism involving spinal canal diameter (SCD). In this study, we utilized machine learning clustering to understand the relationship between SCD and different patterns of cord compression (i.e. compression at one disc level, two disc levels, etc.) to identify patient groups at risk of neurological deterioration. 124 MRI scans from 51 non-operative DCM patients were assessed through manual scoring of cord compression and SCD measurements. Dimensionality reduction techniques and k-means clustering established patient groups that were then defined with their unique risk criteria. We found that the compression pattern is unimportant at SCD extremes (≤14.5 mm or > 15.75 mm). Otherwise, severe spinal cord compression at two disc levels increases deterioration likelihood. Notably, if SCD is normal and cord compression is not severe at multiple levels, deterioration likelihood is relatively reduced, even if the spinal cord is experiencing compression. We elucidated five patient groups with their associated risks of deterioration, according to both SCD range and cord compression pattern. Overall, SCD and focal cord compression alone do not reliably predict an increased risk of neurological deterioration. Instead, the specific combination of narrow SCD with multi-level focal cord compression increases the likelihood of neurological deterioration in mild DCM patients.

Assessing the predictive capability of machine learning models in determining clinical outcomes for patients with cervical spondylotic myelopathy treated with laminectomy and posterior spinal fusion

BACKGROUND

Cervical spondylotic myelopathy (CSM) is a prevalent degenerative condition resulting from spinal cord compression and injury. Laminectomy with posterior spinal fusion (LPSF) is a commonly employed treatment approach for CSM patients. This study aimed to assess the effectiveness of machine learning models (MLMs) in predicting clinical outcomes in CSM patients undergoing LPSF.

METHODS

A retrospective analysis was conducted on 329 CSM patients who underwent LPSF at our institution from Jul 2017 to Jul 2023. Neurological outcomes were evaluated using the modified Japanese Orthopaedic Association (mJOA) scale preoperatively and at the final follow-up. Patients were categorized into two groups based on clinical outcomes: the favorable group (recovery rates ≥ 52.8%) and the unfavorable group (recovery rates < 52.8%). Potential predictors for poor clinical outcomes were compared between the groups. Four MLMs-random forest (RF), logistic regression (LR), support vector machine (SVM), and k-nearest neighborhood (k-NN)-were utilized to predict clinical outcome. RF model was also employed to identify factors associated with poor clinical outcome.

RESULTS

Out of the 329 patients, 185 were male (56.2%) and 144 were female (43.4%), with an average follow-up period of 17.86 ± 1.74 months. Among them, 267 patients (81.2%) had favorable clinical outcomes, while 62 patients (18.8%) did not achieve favorable results. Analysis using binary logistic regression indicated that age, preoperative mJOA scale, and symptom duration (p < 0.05) were independent predictors of unfavorable clinical outcomes. All models performed satisfactorily, with RF achieving the highest accuracy of 0.922. RF also displayed superior sensitivity and specificity (sensitivity = 0.851, specificity = 0.944). The Area under the Curve (AUC) values for RF, Logistic LR, SVM, and k-NN were 0.905, 0.827, 0.851, and 0.883, respectively. The RF model identified preoperative mJOA scale, age, symptom duration, and MRI signal changes as the most significant variables associated with poor clinical outcomes in descending order.

CONCLUSIONS

This study highlighted the effectiveness of machine learning models in predicting the clinical outcomes of CSM patients undergoing LPSF. These models have the potential to forecast clinical outcomes in this patient population, providing valuable prognostic insights for preoperative counseling and postoperative management.

Accuracy of Realigned K-line for Predicting Surgical Outcomes After Laminoplasty in Patients With Degenerative Cervical Myelopathy

STUDY DESIGN

A prospective cohort study.

OBJECTIVES

To report a new index, the realigned K-line, for predicting surgical outcomes after laminoplasty in patients with degenerative cervical myelopathy (DCM).

METHODS

One hundred twenty-eight patients with DCM undergoing laminoplasty were enrolled from January 2018 to April 2021 in our department. A realigned K-line was defined as the line connecting the midpoints of the spinal cord between C2 and C7 on realigned T1-weighted magnetic resonance imaging. The minimum interval between the anterior compression factors of the spinal cord and the realigned K-line (INTrea), and the modified K-line (INTmod) were measured. A logistic regression analysis was performed to identify factors associated with unsatisfactory surgical outcomes. The receiver operating characteristic (ROC) curve and the area under the curve (AUC) was applied to evaluate the reliability of the multivariate logistic regression model.

RESULTS

Univariate analysis showed that the score for the bladder function section of the Japanese Orthopedic Association Cervical Myelopathy Evaluation Questionnaire, numeric rating scale scores for arm pain, and INTrea might be related to the Japanese Orthopaedic Association (JOA) recovery rate (RR) not achieving the minimal clinically important difference (MCID) (P < .05). Only INTrea (odds ratio = .744, P < .05) was an independent preoperative factor related to the JOA RR not achieving the MCID (area under the curve, .743). A cutoff of 5.0 mm for INTrea had an accuracy of 71.9% and specificity of 80.3% for predicting the JOA RR not achieving the MCID.

CONCLUSIONS

INTrea is an independent preoperative risk factor related to the JOA RR not achieving the MCID in patients with DCM. A cutoff point of 5.0 mm is most appropriate for alerting spine surgeons to a high likelihood of the JOA RR not achieving the MCID.

Is It Possible for Patients with Early Distal Junctional Kyphosis following Adult Cervical Deformity Corrective Surgery to Achieve Similar Outcomes to Their Unaffected Counterparts? An Analysis of Recovery Kinetics

Background: Distal junctional kyphosis (DJK) is a concerning complication for surgeons performing cervical deformity (CD) surgery. Patients sustaining such complications may demonstrate worse recovery profiles compared to their unaffected peers. Methods: DJK was defined as a >10° change in kyphosis between LIV and LIV-2, and a >10° index angle. CD patients were grouped according to the development of DJK by 3M vs. no DJK development. Means comparison tests and regression analyses used to analyze differences between groups and arelevant associations. Results: A total of 113 patients were included (17 DJK, 96 non-DJK). DJK patients were more sagittally malaligned preop, and underwent more osteotomies and combined approaches. Postop, DJK patients experienced more dysphagia (17.7% vs. 4.2%; p = 0.034). DJK patients remained more malaligned in cSVA through the 2-year follow-up. DJK patients exhibited worse patient-reported outcomes from 3M to 1Y, but these differences subsided when following patients through to 2Y; they also exhibited worse NDI (65.3 vs. 35.3) and EQ5D (0.68 vs. 0.79) scores at 1Y (both p < 0.05), but these differences had subsided by 2Y. Conclusions: Despite patients exhibiting similar preoperative health-related quality of life metrics, patients who developed early DJK exhibited worse postoperative neck disability following the development of their DJK. These differences subsided by the 2-year follow-up, highlighting the prolonged but eventually successful course of many DJK patients after CD surgery.

Evaluation of the structural integrity of different spinal cord tracts with magnetization transfer ratio in degenerative cervical myelopathy

PURPOSE

Degenerative cervical myelopathy (DCM) is a common cause of spinal cord dysfunction. In this study, we explored the potential of magnetization transfer ratio (MTR) for evaluating the structural integrity of spinal cord tracts in patients with clinically significant DCM.

METHODS

Fifty-three patients with DCM and 41 patients with cervical radiculopathy were evaluated using high-resolution cervical spinal cord magnetic resonance imaging (MRI), which included the magnetization transfer technique. MRI data were analyzed with the Spinal Cord Toolbox (v5.5); MTR values in each spinal tract were calculated and compared between groups after correction for patient age and sex. Correlations between MTR values and patients' clinical disability rate were also evaluated.

RESULTS

A statistically significant reduction in the average MTR of the spinal cord white matter, as well as the MTR of the ventral columns and lateral funiculi, was revealed in the DCM group (adjusted p < 0.01 for all comparisons). Furthermore, reductions in MTR values in the fasciculus cuneatus, spinocerebellar, rubrospinal, and reticulospinal tracts were found in patients with DCM (adjusted p < 0.01 for all comparisons). Positive correlations between the JOA score and the MTR within the ventral columns of the spinal cord (R = 0.38, adjusted p < 0.05) and the ventral spinocerebellar tract (R = 0.41, adjusted p < 0.05) were revealed.

CONCLUSION

The findings of our study indicate that demyelination in patients with DCM primarily affects the spinal tracts of the extrapyramidal system, and the extent of these changes is related to the severity of the condition.

Comparison of radiological and clinical outcomes of cervical laminoplasty versus lateral mass screw fixation in patients with ossification of the posterior longitudinal ligament

PURPOSE

This study aimed to compare cervical sagittal parameters and clinical outcomes between patients undergoing cervical laminoplasty(CL) and those undergoing lateral mass screw fixation(LMS).

METHODS

We retrospectively studied 67 patients with multilevel ossification of the posterior longitudinal ligament (OPLL) of the cervical spine who underwent lateral mass screw fixation (LMS = 36) and cervical laminoplasty (CL = 31). We analyzed cervical sagittal parameters (C2-7 sagittal vertical axis (C2-7 SVA), C0-2 Cobb angle, C2-7 Cobb angle, C7 slope (C7s), T1 slope (T1s), and spino-cranial angle (SCA)) and clinical outcomes (visual analog scale [VAS], neck disability index [NDI], Japanese Orthopaedic Association [JOA] scores, recovery rate (RR), and minimum clinically significant difference [MCID]). The cervical sagittal parameters at the last follow-up were analyzed by binary logistic regression. Finally, we analyzed the correlation between the cervical sagittal parameters and each clinical outcome at the last follow-up after surgery in both groups.

RESULTS

At the follow-up after posterior decompression in both groups, the mean values of C2-C7 SVA, C7s, and T1s in the LMS group were more significant than those in the CL group (P ≤ 0.05). Compared with the preoperative period, C2-C7 SVA, T1s, and SCA gradually increased, and the C2-C7 Cobb angle gradually decreased after surgery (P < 0.05). The improvement in the JOA score and the recovery rate was similar between the two groups, while the improvement in the VAS-N score and NDI score was more significant in the CL group (P = 0.001; P = 0.043). More patients reached MCID in the CL group than in the LMS group (P = 0.036). Binary logistic regression analysis showed that SCA was independently associated with whether patients reached MCID at NDI postoperatively. SCA was positively correlated with cervical NDI and negatively correlated with cervical JOA score at postoperative follow-up in both groups (P < 0.05); C2-7 Cobb angle was negatively correlated with cervical JOA score at postoperative follow-up (P < 0.05).

CONCLUSION

CL may be superior to LMS in treating cervical spondylotic myelopathy caused by OPLL. In addition, smaller cervical SCA after posterior decompression may suggest better postoperative outcomes.

Full endoscopic laminotomy decompression versus anterior cervical discectomy and fusion for the treatment of single-segment cervical spinal stenosis: a retrospective, propensity score-matched study

OBJECTIVE

Anterior cervical discectomy and fusion (ACDF) is the standard procedure for the treatment of cervical spinal stenosis (CSS), but complications such as adjacent segment degeneration can seriously affect the long-term efficacy. Currently, posterior endoscopic surgery has been increasingly used in the clinical treatment of CSS. The aim of this study was to compare the clinical outcomes of single-segment CSS patients who underwent full endoscopic laminotomy decompression or ACDF.

METHODS

138 CSS patients who met the inclusion criteria from June 2018 to August 2020 were retrospectively analyzed and divided into endoscopic and ACDF groups. The propensity score matching (PSM) method was used to adjust the imbalanced confounding variables between the groups. Then, perioperative data were recorded and clinical outcomes were compared, including functional scores and imaging data. Functional scores included Visual Analog Scale of Arms (A-VAS) and Neck pain (N-VAS), Japanese Orthopedic Association score (JOA), Neck Disability Index (NDI), and imaging data included Disc Height Index (DHI), Cervical range of motion (ROM), and Ratio of grey scale (RVG).

RESULTS

After PSM, 84 patients were included in the study and followed for 24-30 months. The endoscopic group was significantly superior to the ACDF group in terms of operative time, intraoperative blood loss, incision length, and hospital stay (P < 0.001). Postoperative N-VAS, A-VAS, JOA, and NDI were significantly improved in both groups compared with the preoperative period (P < 0.001), and the endoscopic group showed better improvement at 7 days postoperatively (P < 0.05). The ROM changes of adjacent segments were significantly larger in the ACDF group at 12 months postoperatively and at the last follow-up (P < 0.05). The RVG of adjacent segments showed a decreasing trend, and the decrease was more marked in the ACDF group at last follow-up (P < 0.05). According to the modified MacNab criteria, the excellent and good rates in the endoscopic group and ACDF group were 90.48% and 88.10%, respectively, with no statistically significant difference (P > 0.05).

CONCLUSION

Full endoscopic laminotomy decompression is demonstrated to be an efficacious alternative technique to traditional ACDF for the treatment of single-segment CSS, with the advantages of less trauma, faster recovery, and less impact on cervical spine kinematics and adjacent segmental degeneration.

Ten-Year Outcomes of Cervical Disc Arthroplasty Versus Anterior Cervical Discectomy and Fusion : A Systematic Review With Meta-Analysis

STUDY DESIGN

A systematic review with meta-analysis of randomized controlled trials and comparative retrospective cohort studies.

OBJECTIVE

The purpose of this study is to compare the 10-year outcomes of cervical disc arthroplasty (CDA) with those of anterior cervical discectomy and fusion (ACDF) for the treatment of cervical degenerative disc disease (CDDD).

SUMMARY OF BACKGROUND DATA

ACDF is the gold standard for the treatment of CDDD. However, the loss of motion at the operative level may accelerate adjacent segment disease (ASD). The preservation of motion with CDA attempts to prevent this complication of cervical fusion. Short-term and mid-term data reveal comparable results for CDA versus ACDF; however, long-term results are unknown.

MATERIALS AND METHODS

A systematic review with meta-analysis was performed to determine if CDA had improved outcomes compared with ACDF at 10-year follow-up. PubMed and Web of Science database searches through 2023 were performed to identify randomized controlled trials and comparative retrospective cohort studies involving treatment of one-level or two-level CDDD.

RESULTS

Six studies were eligible for analysis. CDA had significantly improved neck disability index and visual analog scale scores but lower Japanese Orthopaedic Association scores compared to ACDF at 10-year follow-up ( P < 0.05). None of these results met minimal clinically important differences. CDA had significantly fewer secondary surgeries and adverse events compared to ACDF ( P <0.05). There were no significant differences in neurological success.

CONCLUSIONS

The authors found that significantly fewer secondary surgeries and adverse events were seen after CDA than after ACDF at 10-year follow-up. CDA had statistically, but not clinically, improved neck disability index and visual analog scale scores but lower Japanese Orthopaedic Association scores in comparison to ACDF. CDA was not significantly different from ACDF in terms of a successful neurological outcome.

Residual Paresthesia After Surgery for Degenerative Cervical Myelopathy: Incidence and Impact on Clinical Outcomes and Satisfaction

STUDY DESIGN

Multicenter, prospective cohort study.

OBJECTIVE

The current study aimed to identify the incidence of residual paresthesias after surgery for degenerative cervical myelopathy (DCM), and to demonstrate the impact of these symptoms on clinical outcomes and patient satisfaction.

SUMMARY OF BACKGROUND DATA

Surgery for DCM aims to improve and/or prevent further deterioration of physical function and quality-of-life (QOL) in the setting of DCM. However, patients are often not satisfied with their treatment for myelopathy when they have severe residual paresthesias, even when physical function and QOL are improved after surgery.

MATERIALS AND METHODS

The authors included 187 patients who underwent laminoplasty for DCM. All patients were divided into two groups based on their visual analog scale score for paresthesia of the upper extremities at one year postoperatively (>40 vs. ≤40 mm). Preoperative factors, changes in clinical scores and radiographic factors, and satisfaction scales at one year postoperatively were compared between groups. The authors used mixed-effect linear and logistic regression modeling to adjust for confounders.

RESULTS

Overall, 86 of 187 patients had severe residual paresthesia at one year postoperatively. Preoperative patient-oriented pain scale scores were significantly associated with postoperative residual paresthesia ( P =0.032). A mixed-effect model demonstrated that patients with severe postoperative residual paresthesia showed significantly smaller improvements in QOL ( P =0.046) and myelopathy ( P =0.037) than patients with no/mild residual paresthesia. Logistic regression analysis identified that residual paresthesia was significantly associated with lower treatment satisfaction, independent of improvements in myelopathy and QOL (adjusted odds ratio: 2.5, P =0.010).

CONCLUSION

In total, 45% of patients with DCM demonstrated severe residual paresthesia at one year postoperatively. These patients showed significantly worse treatment satisfaction, even after accounting for improvements in myelopathy and QOL. As such, in patients who experience higher preoperative pain, multidisciplinary approaches for residual paresthesia, including medications for neuropathic pain, might lead to greater clinical satisfaction.

LEVEL OF EVIDENCE

3.

Association Between Preoperative Neuropathic Pain and Patient Reported Outcome Measures After Cervical Spinal Cord Decompression Surgery

STUDY DESIGN

A prospective observational study.

OBJECTIVE

To evaluate the impact on surgical outcomes of preoperative neuropathic pain (NeP) assessed by the painDETECT questionnaire (PDQ) administered to participants undergoing cervical decompression surgery for degenerative cervical myelopathy (DCM).

METHODS

Participating patients were separated into the Non-NeP group (preoperative PDQ score ≤ 12), and NeP group (score ≥ 13). They were asked to complete a booklet questionnaire, including NRS for pain, the Short Form-12 for PCS and MCS, EQ-5D, NDI, and COMI-Neck, at baseline and 1 year after surgery. The JOA score for DCM and radiological changes were also evaluated. Propensity scores were used for the generalized linear model to adjust the patients' backgrounds.

RESULTS

Of the 116 patients recruited, 105 completed the one-year follow-up. In this study, 31 (29.5%) and 74 (70.5%) patients in the NeP and non-NeP groups, respectively, were compared. Except for the higher female ratio in the NeP group (64.6% vs 33.2%, P = .009), preoperative demographic data and surgical factors were not significantly different between both groups. The NeP group showed greater neck/arm/hand NRS scores and worse pre- and postoperative NDI/EQ-5D/COMI-Neck scores at baseline and 1 year after surgery, but this was not significant in the MCS/PCS and JOA scores. Change scores of neck/arm/hand NRS scores and MCS/PCS/NDI/EQ-5D/COMI-Neck scores were not significant between both groups.

CONCLUSIONS

The preoperative NeP, assessed by PDQ, was observed in approximately 30% of patients with DCM who underwent decompression surgery. The presence of NeP was associated with worse pre- and postoperative NDI/EQ-5D/COMI-Neck scores.

Influence of Body Mass Index on Surgical and Patient Outcomes for Cervical Spine Surgery

STUDY DESIGN

Secondary analysis of prospectively collected registry.

OBJECTIVE

We aim to investigate the effects of body mass index (BMI) on postsurgical cervical spine surgery outcomes and identify a potential substratification of obesity with worse outcomes.

SUMMARY OF BACKGROUND DATA

The impact of BMI on cervical spine surgery is unknown, with controversial outcomes for patients high and low BMI.

METHODS

The cervical spine Quality Outcomes Database was queried for a total of 10,381 patients who underwent single-stage cervical spine surgery. Patients were substratified into 6 groups based on BMI. Surgical outcomes, complications, hospitalization outcomes, and patient-reported outcomes for each cohort, including modified Japanese Orthopedic Association Score, Numeric Rating Scale arm pain, Numeric Rating Scale neck pain, Neck Disability Index, and EuroQol Health Survey, were assessed. Univariate analysis was performed for 3- and 12-month follow-up after surgical intervention.

RESULTS

Obese patients (class I, II, and III) requiring spine surgery were statistically younger than nonobese patients and had higher rates of diabetes compared with normal BMI patients. The surgical length was found to be longer for overweight and all classes of obese patients ( P < 0.01). Class III obese patients had higher odds of postoperative complications. Patients with class II and III obesity had lower odds of achieving optimal modified Japanese Orthopedic Association Score at 3 months [OR = 0.8 (0.67-0.94), P < 0.01, OR = 0.68 (0.56-0.82), P < 0.001, respectively] and 12 months [OR = 0.82 (0.68-0.98), P = 0.03, OR = 0.79 (0.64-0.98), P = 0.03, respectively].

CONCLUSIONS

This study investigates the relationship between substratified BMI and postoperative outcomes of cervical spine surgery. Class II and III obese patients have substantially greater risk factors and poor outcomes postoperatively. In addition, low BMI also presents unique challenges for patients. Further research is needed for comprehensive analysis on outcomes of cervical spine surgery after correcting BMI.

Natural history of degenerative cervical myelopathy: a meta-analysis and neurologic deterioration survival curve synthesis

BACKGROUND CONTEXT

Cervical spine surgery is rapidly increasing, and our knowledge of the natural history of degenerative cervical myelopathy (DCM) is limited.

PURPOSE

To synthesize accurate time-based estimates of meaningful neurologic decline in patients with DCM managed conservatively and to provide formulae to help communicate survivorship estimates to patients.

STUDY DESIGN

Systematic review and meta-analysis.

METHODS

A systematic review and meta-analysis was conducted using Cochrane and PRISMA guidelines. A librarian-assisted search strategy using multiple databases with broad search terms and validated filter functions was used. All articles were reviewed in duplicate.

RESULTS

A total of 9570 studies were captured in the initial search, which after deletion of duplicates and manual review of abstracts and full texts revealed 6 studies for analyses. All studies were prospective cohorts or randomized controlled trials. The pooled survival estimates for neurologic stability (95% CrI) for mild DCM patients are: 91% (83%-97%) at one year; 85% (72%-94%) at 2 years; 84% (70%-94%) at 3 years; 75% (54%-90%) at 5 years; 66% (40%-86%) at 15 years; and 65% (39%-86%) at 20 years. The pooled survival estimates for neurologic stability (95% CrI) for moderate/severe DCM patients are: 83% (76%-89%) at 1 year; 72% (62%-81%) at 2 years; 71% (60%-80%) at 3 years; 55% (41%-68%) at 5 years; 44% (27%-59%) at 15 years; and 43% (25%-58%) at 20 years.

CONCLUSIONS

This is the first quantitative synthesis of the totality of published data on DCM natural history. Our review confirms a slow decline in neurologic function. We developed formulae which can be easily used by surgeons to communicate to patients their risk of neurologic deterioration. These formulae can be used to facilitate the shared decision-making process.

Clinical outcome of surgical management of mild cervical compressive myelopathy based on minimum clinically important difference

BACKGROUND CONTEXT

Cervical compressive myelopathy (CCM), caused by cervical spondylosis (cervical spondylotic myelopathy [CSM]) or ossification of the posterior longitudinal ligament (OPLL), is a common neurological disorder in the elderly. For moderate/severe CCM, surgical management has been the first-line therapeutic option. Recently, surgical management is also recommended for mild CCM, and a few studies have reported the surgical outcome for this clinical population. Nonetheless, the present knowledge is insufficient to determine the specific surgical outcome of mild CCM.

PURPOSE

To examine the surgical outcomes of mild CCM while considering the minimum clinically important difference (MCID).

STUDY DESIGN

Retrospective study.

PATIENT SAMPLE

Patients who underwent subaxial cervical surgery for CCM caused by CSM and OPLL between 2013 and 2022 were enrolled.

OUTCOME MEASURES

The Japanese Orthopedic Association score (JOA score) was employed as the clinical outcomes. Based on previous reports, the JOA score threshold to determine mild myelopathic symptoms was set at ≥14.5 points, and the MCID of the JOA score for mild CCM was set at 1 point.

METHODS

The patients with a JOA score of ≥14.5 points at baseline were stratified into the mild CCM and were examined while considering the MCID. The mild CCM cohort was dichotomized into the improvement group, including the patients with an achieved MCID (JOA score ≥1 point) or with a JOA score of 17 points (full mark) at 1 year postoperatively, and the nonimprovement group, including the others. Demographics, symptomatology, radiographic findings, and surgical procedure were compared between the two groups and studied using the receiver operating characteristic (ROC) curve.

RESULTS

Of 335 patients with CCM, 43 were stratified into the mild CCM cohort (mean age, 58.5 years; 62.8% male). Among them, 25 (58.1 %) patients were assigned to the improvement group and 18 (41.9 %) were assigned to the nonimprovement group. The improvement group was significantly younger than the nonimprovement group; however, other variables did not significantly differ. ROC curve analysis showed that the optimal cutoff point of the patient's age to discriminate between the improvement and nonimprovement groups was 58 years with an area under the curve of 0.702 (p=.015).

CONCLUSIONS

In the present study, the majority of patients with mild CCM experienced improvement reaching the MCID of JOA score at 1 year postoperatively. The present study suggests that for younger patients with mild CCM, especially those aged below 58 years, subjective neurological recovery is more likely to be obtained. Meanwhile, the surgery takes on a more prophylactic significance to halt disease progression for older patients. The results of this study can help in the decision-making process for this clinical population.

Aided diagnosis of cervical spondylotic myelopathy using deep learning methods based on electroencephalography

Cervical spondylotic myelopathy (CSM) is the most severe type of cervical spondylosis. It is challenging to achieve early diagnosis with current clinical diagnostic tools. In this paper, we propose an end-to-end deep learning approach for early diagnosis of CSM. Electroencephalography (EEG) experiments were conducted with patients having spinal cord cervical spondylosis and age-matched normal subjects. A Convolutional Neural Network with Long Short-Term Memory Networks (CNN-LSTM) model was employed for the classification of patients versus normal individuals. In contrast, a Convolutional Neural Network with Bidirectional Long Short-Term Memory Networks and attention mechanism (CNN-BiLSTM-attention) model was used to classify regular, mild, and severe patients. The models were trained using focal Loss instead of traditional cross-entropy Loss, and cross-validation was performed. Our method achieved a classification accuracy of 92.5 % for the two-class classification among 40 subjects and 72.2 % for the three-class classification among 36 subjects. Furthermore, we observed that the proposed model outperformed traditional EEG decoding models. This paper presents an effective computer-aided diagnosis method that eliminates the need for manual extraction of EEG features and holds potential for future auxiliary diagnosis of spinal cord-type cervical spondylosis.

Does Surgical Treatment Affect the Degree of Anxiety or Depression in Patients With Degenerative Cervical Myelopathy?

STUDY DESIGN

Retrospective cohort study.

OBJECTIVES

Preoperative mental state has been reported as one of the factors affecting the surgical outcomes of spine surgery, but few studies have examined in detail how patients' mental state is affected by spine surgery. The purpose of this study was to investigate using the Hospital Anxiety and Depression Scale (HADS) whether surgery improves preoperative depression and anxiety in patients with degenerative cervical myelopathy.

METHODS

We investigated patient-reported outcomes (Mental Component Summary, Physical Component Summary of SF-12 Health Survey, and EQ-5D, Neck Disability Index, JOACMEQ, satisfaction with treatment) and HADS one year after surgery, comparing them before and after surgery between April 2017 and February 2020. Among the cases diagnosed as preoperative anxiety and depression, we additionally compared the patient-reported outcomes based on the presence or absence of postoperative improvement in mental state, having also investigated the correlation between patient-reported outcomes and HADS for sub-analysis.

RESULTS

Among the 99 patients eligible for inclusion in the present study, we found that patient-reported outcomes and the HADS scores improved significantly after surgery. There was a moderate correlation between the amount of change in HADS-D score before and after surgery and the amount of change in NDI (moderate, r = .41), NRS of neck (moderate, r = .46), and JOACMEQ (cervical spine function; moderate, r = .43, upper extremity function; moderate, r = .41, QOL; moderate, r = .41).

CONCLUSIONS

We found that surgical treatment for patients with degenerative cervical myelopathy may improve postoperative anxiety and depression as well as other patient-reported outcomes.

The Deterioration of Cervical Kyphosis During Neck Flexion after Laminoplasty Affects the Surgical Outcome of Cervical Spondylotic Myelopathy

STUDY DESIGN

A retrospective single-center study.

OBJECTIVE

The present study investigated whether postoperative cervical alignment changes, in addition to preoperative patient backgrounds, imaging parameters, and disease severity, affect outcomes 1 year after laminoplasty.

METHODS

One hundred and three cervical spondylotic myelopathy (CSM) patients who underwent laminoplasty were enrolled. Preoperative and postoperative (1-year) Japanese Orthopedic Association (JOA) scores, cervical alignment, and balance on X-rays were assessed. Patients were classified into 2 groups for a univariate analysis according to the status of the recovery rate (RR) of the JOA score ≥50%. A multiple logistic regression analysis was performed to identify factors associated with good surgical outcomes a.

RESULTS

The mean RR of the JOA score was 47.5% and the loss of cervical lordosis in the neutral position was 5.5°. The univariate analysis revealed slight differences in age, sex, and the duration of disease. Preoperative C2-7 angles were not significantly different. The C2-7 angle during flexion after surgery was significantly smaller in Group F. In the multiple logistic regression analysis, significant factors associated with the status of RR≥50% were a younger age (OR: .75, 95%CI: .59-.96), shorter duration of disease (OR: .94, 95%CI: .89-.99), and a lordotic C2-7 angle during neck flexion after surgery (OR: 1.47, 95%CI: 1.1-1.95).

CONCLUSION

We retrospectively assessed the surgical outcomes of laminoplasty in 103 CSM cases. In addition to an older age and longer duration of disease, postoperative deteriorations in cervical kyphosis during neck flexion had a negative impact on outcomes.

Risk Factors of Nonfusion after Anterior Cervical Decompression and Fusion in the Early Postoperative Period: A Retrospective Study

OBJECTIVE

Although high fusion rates have been reported for anterior cervical decompression and fusion (ACDF) in the medium and long term, the risk of nonfusion in the early period after ACDF remains substantial. This study investigates early risk factors for cage nonfusion in patients undergoing single- or multi-level ACDF.

METHODS

This was a retrospective study. From August 2020 to December 2021, 107 patients with ACDF, including 197 segments, were enrolled, with a follow-up of 3 months. Among the 197 segments, 155 were diagnosed with nonfusion (Nonfusion group), and 42 were diagnosed with fusion (Fusion group) in the early period after ACDF. We assessed the significance of the patient-specific factors, radiographic indicators, serum factors, and clinical outcomes. The Wilcoxon rank sum test, t-tests, analysis of variance, and stepwise multivariate logistic regression were used for statistical analysis.

RESULTS

Univariate analysis showed that smoking, insufficient improvement in the C2-7 Cobb angle (p = 0.024) and the functional spinal unit Cobb angle (p = 0.022) between preoperative and postoperative stages and lower serum calcium (fusion: 2.34 ± 0.12 mmol/L; nonfusion: 2.28 ± 0.17 mmol/L, p = 0.003) β-carboxyterminal telopeptide end of type 1 collagen (β-CTX) (fusion: 0.51 [0.38, 0.71]; nonfusion: 0.43 [0.31, 0.57], p = 0.008), and N-terminal fragment of osteocalcin (N-MID-BGP) (fusion: 18.30 [12.15, 22.60]; nonfusion: 14.45 [11.65, 18.60], p = 0.023) are risk factors for nonfusion in the early period after ACDF. Stepwise logistic regression analysis revealed that poor C2-7 Cobb angle improvement (odds ratio [OR], 1.107 [1.019-1.204], p = 0.017) and lower serum calcium (OR, 3.700 [1.138-12.032], p = 0.030) are risk factors.

CONCLUSIONS

Patients with successful fusion after ACDF had higher preoperative serum calcium and improved C2-7 Cobb angle than nonfusion patients at 3 months. These findings suggest that serum calcium could be used to identify patients at risk of nonfusion following ACDF and that correcting the C2-7 Cobb angle during surgery could potentially increase fusion in the early period after ACDF.

Quality of Life and Postoperative Satisfaction in Patients with Benign Extramedullary Spinal Tumors: A Multicenter Study

STUDY DESIGN

Retrospective cohort study using prospectively collected registry data.

OBJECTIVE

The purpose of this study is to evaluate health-related quality of life (HRQOL) and postoperative satisfaction in patients with different histotypes of benign extramedullary spinal tumors (ESTs).

BACKGROUND

Little is known about how different histotypes influence HRQOL and postoperative satisfaction in EST patients.

MATERIALS AND METHODS

Patients undergoing primary benign EST surgery at 11 tertiary referral hospitals between 2017 and 2021 who completed preoperative and 1-year postoperative questionnaires were included. HRQOL assessment included the Physical Component Summary and Mental Component Summary (MCS) of Short Form-12, EuroQol 5-dimension, Oswestry/Neck Disability Index (ODI/NDI), and Numeric Rating Scales (NRS) for upper/lower extremities (UEP/LEP) and back pain (BP). Patients who answered "very satisfied," "satisfied," or "somewhat satisfied" on a seven-point Likert scale were considered to be satisfied with treatment. Student t -tests or Welch's t -test were used to compare continuous variables between two groups, and one-way analysis of variance was used to compare outcomes between the three groups of EST histotypes (schwannoma, meningioma, atypical). Categorical variables were compared using the χ 2 test or Fisher exact test.

RESULTS

A total of 140 consecutive EST patients were evaluated; 100 (72%) had schwannomas, 30 (21%) had meningiomas, and 10 (7%) had other ESTs. Baseline Physical Component Summary was significantly worse in patients with meningiomas ( P =0.04), and baseline NRS-LEP was significantly worse in patients with schwannomas ( P =0.03). However, there were no significant differences in overall postoperative HRQOL or patient satisfaction between histology types. Overall, 121 (86%) patients were satisfied with surgery. In a subgroup analysis comparing intradural schwannomas and meningiomas adjusted for patient demographics and tumor location with inverse probability weighting, schwannoma patients had worse baseline MCS ( P =0.03), ODI ( P =0.03), NRS-BP ( P <.001), and NRS-LEP ( P =0.001). Schwannoma patients also had worse postoperative MCS ( P =0.03) and NRS-BP ( P =0.001), with no significant difference in the percentage of satisfied patients ( P =0.30).

CONCLUSIONS

Patients who underwent primary benign EST resection had a significant improvement in HRQOL postoperatively, and ~90% of these patients reported being satisfied with their treatment outcomes one year after surgery. EST patients may exhibit a relatively lower threshold for postoperative satisfaction compared with patients undergoing surgery for degenerative spine conditions.

Factors Associated With Loss of Cervical Lordosis After Laminoplasty for Patients With Cervical Ossification of the Posterior Longitudinal Ligament: Data From a Prospective Multicenter Study

STUDY DESIGN

A prospective multicenter study.

OBJECTIVE

The objective of this study was to investigate the incidence of loss of cervical lordosis after laminoplasty for cervical ossification of the posterior longitudinal ligament (OPLL). We also sought to determine associated risk factors and the relationship with patient-reported outcomes.

SUMMARY OF BACKGROUND DATA

Loss of cervical lordosis is a sequelae often observed after laminoplasty, which may adversely impact surgical outcomes. Cervical kyphosis, especially in OPLL, is associated with reoperation, but risk factors and relationship to postoperative outcomes remain understudied at this time.

MATERIALS AND METHODS

This study was conducted by the Japanese Multicenter Research Organization for Ossification of the Spinal Ligament. We included 165 patients who underwent laminoplasty and completed Japanese Orthopaedic Association (JOA) score or Japanese Orthopaedic Association Cervical Myelopathy Evaluation Questionnaires (JOACMEQ), as well as Visual Analog Scales (VAS) for pain, with imaging. The participants were divided into two groups: those with loss of cervical lordosis of >10° or 20° after surgery and those without loss of cervical lordosis. A paired t test was applied to evaluate the association between changes in cervical spinal angles, range of motion, and cervical JOA and VAS scores before and at 2 years postoperatively. Mann-Whitney U test was used for JOACMEQ.

RESULTS

Postoperative loss of cervical lordosis >10° and >20° was observed in 32 (19.4%) and 7 (4.2%), respectively. JOA, JOACMEQ, and VAS scores were not significantly different between those with, and without, loss of cervical lordosis. Preoperative small extension range of motion (eROM) was significantly associated with postoperative loss of cervical lordosis, and the cutoff values of eROM were 7.4° [area under the curve (AUC): 0.76] and 8.2° (AUC: 0.92) for loss of cervical lordosis >10° and >20°, respectively. A large occupation ratio of OPLL was also associated with loss of cervical lordosis, with a cutoff value of 39.9% (AUC: 0.94). Laminoplasty resulted in functional improvement in most patient-reported outcomes; however, neck pain and bladder function tended to become worse postoperatively in cases with postoperative loss of cervical lordosis >20°.

CONCLUSIONS

JOA, JOACMEQ, and VAS scores were not significantly different between those with, and without, loss of cervical lordosis. Preoperative small eROM and large OPLL may represent factors associated with loss of cervical lordosis after laminoplasty in patients with OPLL.

Comparison of clinical outcomes of modified laminoplasty with preservation of muscle group inserted into C2 and C7 spinous processes versus conventional C3-C7 laminoplasty: a prospective, randomized, controlled, noninferiority trial

BACKGROUND

The efficacy and noninferior of performing modified double-door laminoplasty (MDDL) (C4-C6 laminoplasty plus C3 laminectomy, alongside a dome-like resection of the inferior part of the C2 lamina and the superior part of the C7 lamina) in patients with multilevel cervical spondylotic myelopathy (MCSM) is equivocal. A randomized, controlled trial is warranted.

OBJECTIVE

The objective was to evaluate the clinical efficacy and noninferior of MDDL compared with traditional C3-C7 double-door laminoplasty.

STUDY DESIGN

A single-blind, randomized, controlled trial.

METHODS

A single-blind, randomized, controlled trial was conducted in which patients who with MCSM with greater than or equal to 3 levels of spinal cord compression from the C3 to the C7 vertebral levels were enrolled and assigned to undergo either MDDL group or conventional double-door laminoplasty (CDDL) group in a 1:1 ratio. The primary outcome was the change in the Japanese Orthopedic Association score from baseline to 2-year follow-up. The secondary outcomes included changes in the Neck Disability Index (NDI) score, the Visual Analog Scale (VAS) for neck pain, and imaging parameters. Operative complications were also collected and reported. The outcome measures were compared between the groups at 3 months, 1 year, or 2 years after surgery.

RESULTS

A total of 96 patients (mean age 67 years, 39.8% women) underwent randomization. Of these patients, 93 completed 3-month follow-up, 79 completed 1-year follow-up, and 66 completed 2-year follow-up. The changes in the Japanese Orthopedic Association score did not differ significantly between the study groups at the three time points after surgery. With respect to amelioration of neck pain and disability related to neck pain, patients in the MDDL group had a significantly greater decrease in the VAS and NDI component summary score than did those in the CDDL group at 1-year (VAS: -2.5 vs. -3.2, difference -0.7, 95% CI -1.1 to -0.2, P =0.0035; NDI: -13.6 vs. -19.3, difference -5.7, 95% CI -10.3 to -1.1, P =0.0159) and 2-years (VAS: -2.1 vs. -2.9, difference -0.8, 95% CI -1.4 to -0.2, P =0.0109; NDI: -9.3 vs. -16.0, difference -6.7, 95% CI -11.9 to -1.5, P =0.0127). The changes in the range of motion (ROM), the C2-C7 Cobb angle, and the cervical sagittal vertical axis in the MDDL group were significantly less than those in the CDDL group (ROM: -9.2±6.4 vs. -5.0±6.0, P =0.0079; C2-C7 Cobb angle: -7.9±7.8 vs. -4.1±6.2, P =0.0345; cervical sagittal vertical axis: 0.6±0.9 vs. 0.2±0.6, P =0.0233). The MDDL group had less blood loss (428.1 vs. 349.1, P =0.0175) and a lower rate of axial symptoms (27.3 vs. 6.1%, P =0.0475) than the CDDL group.

CONCLUSIONS

Among patients with MCSM, the MDDL produced similar cervical cord decompression compared with the conventional C3-C7 double-door laminoplasty. The modified laminoplasty was associated with meaningful improvement in amelioration of neck discomfort, maintaining a better cervical ROM and sagittal alignment, decreasing blood loss, and reducing the incidence of axial symptoms.

Laminoplasty is relevant for degenerative cervical spondylolisthesis when there is little risk of postoperative excessive kyphosis during neck flexion

BACKGROUND

Elderly patients with degenerative cervical myelopathy frequently have severe symptoms due to spondylolisthesis. The effectiveness of laminoplasty for degenerative cervical spondylolisthesis (DCS) is an important question.

OBJECTIVE

The aim of this study is to elucidate factors associated with the outcome of laminoplasty for DCS.

METHOD

Eighty-nine patients with cervical spondylotic myelopathy (CSM) who underwent laminoplasty without instrumented posterior fusion were enrolled. Positive spondylolisthesis was defined as more than 2 mm during neck flexion or extension, from this, 46 DCS cases and 43 non-DCS cases were classified. Radiological parameters, including cervical alignment, balance, range of motion, and slippage along with the Japanese Orthopedic Association (JOA) score, were obtained before and 1 year after surgery. Factors associated with good surgical outcomes for DCS were analyzed using multivariate logistic analysis.

RESULTS

There were no significant differences in background and preoperative JOA score, but the DCS group recovery rate was significantly less (42% vs 53%). Multivariate logistic analysis revealed only the postoperative C2-7 angle during neck flexion was associated with a favorable outcome for DCS (P = 0.0039, Odds ratio: 1.49, 95% CI: 1.14-1.94). Multivariate regression analysis positively correlated the preoperative C2-7 angle in neutral and during flexion with the postoperative C2-7 angle during flexion.

CONCLUSION

The major factor related to poor outcome was the magnitude of postoperative kyphotic C2-7 angle during neck flexion. Slippage was not directly related to outcome and postoperative cervical alignment. Caution is recommended for surgeons performing laminoplasty on patients with risk factors for postoperative excessive kyphotic C2-7 angle during flexion.

Is 3D-printed Titanium cage a reliable option for 3-level anterior cervical discectomy and fusion in treating degenerative cervical spondylosis?

Background

To assess the clinical and radiographical outcomes of 3-level anterior cervical discectomy and fusion (ACDF) with a 3D-printed titanium cage in treating degenerative cervical spondylosis.

Methods

In this study, 25 patients with degenerative cervical spondylosis who underwent 3-level ACDF using a 3D-printed titanium cage from March 2019 to June 2021 were retrospectively enrolled. The patient-reported outcome measures (PROMs) were evaluated by visual analog scale (VAS) for the neck (VAS-neck) and arm pain (VAS-arm), Neck Disability Index (NDI) score, Japanese Orthopedic Association (JOA) score, SF-12 concise health survey, and the Odom criteria. The radiographical parameters, including C2-C7 lordosis, segmental angle, segmental height, and subsidence, were assessed. The mean duration of follow-up was 25.6 months.

Results

Bony fusion was achieved in all patients (100%). In three patients (12%) mild dysphagia was observed during the follow-up. The VAS-neck, VAS-arm, NDI score, JOA score, SF-12 score, C2-C7 lordosis, and segmental angle improved noticeably at the latest follow-up. Based on the Odom criteria, 22 patients (88%) reported satisfactory (excellent or good). The mean loss of C2-C7 lordosis and segmental angle between the immediate postoperative and the latest follow-up values were 1.6° ± 0.5° and 1.1° ± 0.5°, respectively. The mean subsidence was 0.9 ± 0.6 mm.

Conclusion

In patients with multi-level degenerative cervical spondylosis, 3-level ACDF using the 3D-printed titanium cage can effectively relieve the symptoms, stabilize the spine, and restore segmental height and cervical curvature. It is proven to be a reliable option for patients with 3-level degenerative cervical spondylosis. However, a future comparative study involving a larger population and longer follow-up time may be required to further evaluate the safety, efficacy and outcomes of our preliminary results.

Trends in Outcomes of a Prospective Consecutively Enrolled Single-Center Adult Cervical Deformity Series

STUDY DESIGN

Retrospective cohort.

OBJECTIVE

The aim was to describe the two-year outcomes for patients undergoing surgical correction of cervical deformity (CD).

BACKGROUND

Adult CD has been shown to compromise health-related quality of life. While advances in spinal realignment have shown promising short-term clinical results in this parameter, the long-term outcomes of CD corrective surgery remain unclear.

MATERIALS AND METHODS

Operative CD patients >18 years with two-year (2Y) health-related quality of life/radiographic data were included. Improvement in radiographic, neurologic, and health-related quality of life outcomes were reported. Patients with a prior cervical fusion and patients with the greatest and smallest change based on Neck Disability Index (NDI), numeric rating scale (NRS) neck, modified Japanese Orthopaedic Association (mJOA) were compared using multivariable analysis controlling for age, and frailty, and invasiveness.

RESULTS

One hundred and fifty-eight patients were included in this study. By 2Y, 96.3% of patients improved in Ames cervical sagittal vertical axis modifier, 34.2% in T1 slope minus cervical lordosis (TS-CL), 42.0% in horizontal gaze modifier, and 40.9% in SVA modifier. In addition, 65.5% of patients improved in Passias CL modifier, 53.3% in TS-CL modifier, 100% in C2-T3 modifier, 88.9% in C2S modifier, and 81.0% in MGS modifier severity by 2Y. The cohort significantly improved from baseline to 2Y in NDI, NRS Neck, and mJOA, all P <0.05. 59.3% of patients met minimal clinically important difference for NDI, 62.3% for NRS Neck, and 37.3% for mJOA. Ninety-seven patients presented with at least one neurologic deficit at baseline and 63.9% no longer reported that deficit at follow-up. There were 45 (34.6%) cases of distal junctional kyphosis (DJK) (∆DJKA>10° between lower instrumented vertebra and lower instrumented vertebra-2), of which 17 were distal junctional failure (distal junctional failure-DJK requiring reoperation). Patients with the greatest beneficial change were less likely to have had a complication in the two-year follow-up period.

CONCLUSION

Correction of CD results in notable clinical and radiographic improvement with most patients achieving favorable outcomes after two years. However, complications including DJK or failure remain prevalent.

Prospective Investigation of Surgical Outcomes after Anterior Decompression with Fusion and Laminoplasty for the Cervical Ossification of the Posterior Longitudinal Ligament: A Propensity Score Matching Analysis

The ideal surgical strategy for cervical ossification of the posterior longitudinal ligament (OPLL) remains controversial due to the lack of high-quality evidence. Herein, we prospectively investigated the surgical outcomes of anterior cervical decompression with fusion (ADF) and laminoplasty (LAMP) with cervical OPLL. Three hundred patients were included in this study (ADF: n = 89; LAMP: n = 211 patients), and propensity score matching yielded 67 pairs of patients with ADF and LAMP, in which clinical outcomes were compared. Crude analysis revealed that the ADF group showed greater neurological recovery in cervical Japanese Orthopedic Association scores at two years, compared with that in the LAMP group (53.1% vs. 44.3%, p = 0.037). The ratio of minimum clinically important difference (MCID) success was significantly greater in the ADF group (59.6% vs. 43.6%, p = 0.016). Multivariate analysis showed that the factors affecting MCID success were age, body mass index, duration of symptoms, and choice of ADF. In the 1:1 matched analysis, neurological improvement was more favorable in the ADF group (57.2%) compared to the LAMP group (46.8%) at two years (p = 0.049). However, perioperative complications, such as dysphagia and graft-related complications, were more common in the ADF group.

Instrumentation Across the Cervicothoracic Junction Does Not Improve Patient-reported Outcomes in Multilevel Posterior Cervical Decompression and Fusion

STUDY DESIGN

This was a retrospective cohort.

OBJECTIVE

The objective of this study was to determine if instrumentation across the cervicothoracic junction (CTJ) in elective multilevel posterior cervical decompression and fusion (PCF) is associated with improved patient-reported outcome measures (PROMs).

SUMMARY OF BACKGROUND DATA

Fusion across the CTJ may result in lower revision rates at the expense of prolonged operative duration. However, it is unclear whether constructs crossing the CTJ affect PROMs.

MATERIALS AND METHODS

Standard Query Language (SQL) identified patients with PROMs who underwent elective multilevel PCF (≥3 levels) at our institution. Patients were grouped based on anatomic construct: crossing the CTJ (crossed) versus not crossing the CTJ (noncrossed). Subgroup analysis compared constructs stopping at C7 or T1. Independent t tests and χ 2 tests were utilized for continuous and categorical data, respectively. Regression analysis controlled for baseline demographics. The α was set at 0.05.

RESULTS

Of the 160 patients included, the crossed group (92, 57.5%) had significantly more levels fused (5.27 vs. 3.71, P <0.001), longer operative duration (196 vs. 161 min, P =0.003), greater estimated blood loss (242 vs. 160 mL, P =0.021), and a decreased revision rate (1.09% vs. 10.3%, P =0.011). Neither crossing the CTJ (vs. noncrossed) nor constructs spanning C3-T1 (vs. C3-C7) were independent predictors of ∆PROMs (change in preoperative minus postoperative patient-reported outcomes) on regression analysis. However, C3-C7 constructs had a greater revision rate than C3-T1 constructs (15.6% vs. 1.96%, P =0.030).

CONCLUSION

Crossing the CTJ in patients undergoing elective multilevel PCF was not an independent predictor of improvement in PROMs at 1 year, but they experienced lower revision rates.

LEVEL OF EVIDENCE

Level III.

Depression Increases Posterior Cervical Decompression and Fusion Revision Rates and Diminishes Neck Disability Index Improvement

STUDY DESIGN

A retrospective cohort study.

OBJECTIVE

To determine if depression and/or anxiety significantly affect patient-reported outcome measures (PROMs) after posterior cervical decompression and fusion (PCDF).

SUMMARY OF BACKGROUND DATA

Mental health diagnoses are receiving increased recognition for their influence of outcomes after spine surgery. The magnitude that mental health disorders contribute to patient-reported outcomes following PCDF requires increased awareness and understanding.

MATERIALS AND METHODS

A review of electronic medical records identified patients who underwent a PCDF at a single institution during the years 2013-2020. Patients were placed into either depression/anxiety or nondepression/anxiety group based on their medical history. A delta score (∆) was calculated for all PROMs by subtracting postoperative from preoperative scores. χ 2 tests and t tests were utilized to analyze categorical and continuous data, respectively. Regression analysis determined independent predictors of change in PROMs. Alpha was set at 0.05.

RESULTS

A total of 195 patients met inclusion criteria, with 60 (30.8%) having a prior diagnosis of depression/anxiety. The depression/anxiety group was younger (58.8 vs . 63.0, P =0.012), predominantly female (53.3% vs . 31.9%, P =0.007), and more frequently required revision surgery (11.7% vs . 0.74%, P =0.001). In addition, they had worse baseline mental component (MCS-12) (42.2 vs . 48.6, P <0.001), postoperative MCS-12 (46.5 vs . 52.9, P =0.002), postoperative neck disability index (NDI) (40.7 vs . 28.5, P =0.001), ∆NDI (-1.80 vs . -8.93, P =0.010), NDI minimum clinically important difference improvement (15.0% vs . 29.6%, P =0.046), and postoperative Visual Analog Scale (VAS) Neck scores (3.63 vs . 2.48, P =0.018). Only the nondepression/anxiety group improved in MCS-12 ( P =0.002) and NDI ( P <0.001) postoperatively. Depression and/or anxiety was an independent predictor of decreased magnitude of NDI improvement on regression analysis (β=7.14, P =0.038).

CONCLUSION

Patients with history of depression or anxiety demonstrate less improvement in patient-reported outcomes and a higher revision rate after posterior cervical fusion, highlighting the importance of mental health on clinical outcomes after spine surgery.

Comparison Between the Japanese Orthopaedic Association (JOA) Score and Patient-Reported JOA (PRO-JOA) Score to Evaluate Surgical Outcomes of Degenerative Cervical Myelopathy

STUDY DESIGN

A retrospective cohort study.

OBJECTIVE

To investigate whether the Japanese Orthopaedic Association (JOA) score can be used for patients with degenerative cervical myelopathy as a patient-reported outcome (PRO) through the JOA written questionnaire.

METHODS

A total of 75 patients who underwent posterior decompression surgery for degenerative cervical myelopathy were reviewed. Patients responded to questionnaires including PRO-JOA, EuroQOL-5D, Neck Disability Index, and Short Form-12 preoperatively and at >12 months postoperatively. Spearman's rho and Bland-Altman analyses were used to investigate the correlations.

RESULTS

Preoperative JOA and PRO-JOA scores were 10.8 and 10.6, respectively, with Spearman's rho of 0.74. Similarly, postoperative JOA and PRO-JOA scores were 13.3 and 12.9, respectively, with Spearman's rho of 0.68. However, the recovery rates for JOA and PRO-JOA scores were 42% and 27%, respectively, with Spearman's rho of 0.45. Compared with other PROs, JOA and PRO-JOA scores were moderately correlated. The minimum clinically important difference was 2.5 for JOA score, 3.0 for PRO-JOA score, 42% for JOA recovery rate, and 33% for PRO-JOA recovery rate. Bland-Altman analyses revealed that limits of agreement were -4.3 to 4.7, -3.4 to 4.3, and -75% to 106% for the preoperative score, postoperative score, and recovery rate, respectively.

CONCLUSION

PRO-JOA score can also be used as a disease-specific scoring measure instead of JOA score. However, although both measures demonstrate a similar trend as a group analysis, PRO-JOA and JOA scores should be regarded as different outcomes.

Impact of obesity on cervical ossification of the posterior longitudinal ligament: a nationwide prospective study

Positive association between ossification of the posterior longitudinal ligament of the spine (OPLL) and obesity is widely recognized; however, few studies focused on the effects of obesity on treatment of cervical OPLL. The effects of obesity on surgical treatment of cervical OPLL were investigated by a Japanese nationwide, prospective study. Overall, 478 patients with cervical myelopathy due to OPLL were prospectively enrolled. To clarify the effects of obesity on the surgical treatment for cervical OPLL, patients were stratified into two groups, non-obese (< BMI 30.0 kg/m2) and obese (≥ BMI 30.0 kg/m2) groups. The mean age of the obese group was significantly younger than that of non-obese group. There were no significant differences between the two groups in other demographic information, medical history, and clinical and radiographical findings. Alternatively, the obese group had a significantly higher rate of surgical site infection (SSI) than that of non-obese group. Approach-specific analyses revealed that the SSI was significantly higher in the obese group than in the non-obese group. A logistic regression analysis revealed that age, BMI, and duration of symptoms were significant factors affecting the postoperative minimum clinically important difference success. The result of this study provides useful information for future cervical OPLL treatment.

Minimal clinically important difference in patients who underwent decompression alone for lumbar degenerative disease

BACKGROUND CONTEXT

The minimal clinically important difference (MCID) represents the smallest change in an outcome measure recognized as clinically meaningful to a patient after receiving a clinical intervention. Most studies that discussed the MCIDs for lumbar spinal stenosis (LSS) included mixed pathologies or procedures despite that the MCID value should be different depending on the intervention. Moreover, despite the efficacy of adopting percentage-change improvement for the MCID threshold, there are limited reports and discussions in the field of lumbar surgery.

PURPOSE

The aim of the present study was to elucidate the MCIDs for the Oswestry Disability Index (ODI), EuroQOL 5-dimension 3-level (EQ-5D-3L), physical component summary (PCS) of the Short Form of the Medical Outcomes Study, and Numeric Rating Scale (NRS) in patients with degenerative LSS treated with decompression surgery without fusion.

STUDY DESIGN/SETTING

A multicenter retrospective cohort study was performed.

PATIENT SAMPLE

A total of 422 patients who underwent decompression surgery for LSS and answered a complete set of questionnaires were included in the study. Patients who underwent endoscopic or revision surgery were excluded.

OUTCOME MEASURES

Preoperative and 1-year postoperative scores of each health-related quality of life questionnaires (HRQOLs) and patient satisfaction questionnaire response METHODS: The patient satisfaction question was used as an anchor, and the cutoff values were estimated based on absolute point improvement from baseline using a receiver-operating characteristic (ROC) curve analysis and the "mean change" method for MCIDs. The MCID values for percentage-change in HRQOLs were also calculated using ROC curve analysis. The three cutoff values for each HRQOL were validated using the Youden index for determining the most robust MCIDs.

RESULTS

Of the patients, 356 (84.4%) were at least "somewhat satisfied" with the treatment results. The two cutoff values of absolute point-change in each HRQOL, which were estimated by two different anchor-based methods, were similar. The area under the curve of the ROC curve for percentage-change tended to be higher than that for absolute point-change. Moreover, the Youden index of the percentage-change in each HRQOL was higher than that of the absolute point-change calculated by either the "mean change" method or the ROC curve analysis. Based on these results, it was proposed that MCID was 42.4% for percentage-change in ODI, 22.0% for EQ-5D-3L, 13.7% for PCS, 25.0% for NRS (low back pain), 55.6% for NRS (leg pain), 22.2% for NRS (leg numbness).

CONCLUSIONS

The MCIDs of HRQOLs were calculated in patients with LSS treated with decompression surgery without concomitant fusion procedure. The MCID cutoffs based on percentage-change from baseline were more effective than those of absolute point-change.

Clinical improvement after surgery for degenerative cervical myelopathy; A comparison of Patient-Reported Outcome Measures during 12-month follow-up

OBJECT

Although many patients report clinical improvement after surgery due to degenerative cervical myelopathy, the aim of intervention is to stop progression of spinal cord dysfunction. We wanted to provide estimates and assess achievement rates of Minimal Clinically Important Difference (MCID) at 3- and 12-month follow-up for Neck Disability Index (NDI), Numeric Rating Scale for arm pain (NRS-AP) and neck pain (NRS-NP), Euro-Qol (EQ-5D-3L), and European Myelopathy Score (EMS).

METHODS

614 degenerative cervical myelopathy patients undergoing surgery responded to Patient-Reported Outcome Measures (PROMs) prior to, 3 and 12 months after surgery. External criterion was the Global Perceived Effect Scale (1-7), defining MCID as "slightly better", "much better" and "completely recovered". MCID estimates with highest sensitivity and specificity were calculated by Receiver Operating Curves for change and percentage change scores in the whole sample and in anterior and posterior procedural groups.

RESULTS

The NDI and NRS-NP percentage change scores were the most accurate PROMs with a MCID of 16%. The change score for NDI and percentage change scores for NDI, NRS-AP and NRS-NP were slightly higher in the anterior procedure group compared to the posterior procedure group, while remaining PROM estimates were similar across procedure type. The MCID achievement rates at 12-month follow-up ranged from 51% in EMS to 62% in NRS-NP.

CONCLUSION

The NDI and NRS-NP percentage change scores were the most accurate PROMs to measure clinical improvement after surgery for degenerative cervical myelopathy. We recommend using different cut-off estimates for anterior and posterior approach procedures. A MCID achievement rate of 60% or less must be interpreted in the perspective that the main goal of surgery for degenerative cervical myelopathy is to prevent worsening of the condition.

Curative Effects of Remote Home Management Combined with Feng’s Spinal Manipulation on the Treatment of Elderly Patients with Lumbar Disc Herniation

Objective

To explore the curative effects of remote home management combined with Feng's spinal manipulation on the treatment of elderly patients with lumbar disc herniation (LDH).

Methods

The clinical data of 100 patients with LDH in our hospital (December 2019–December 2020) were retrospectively reviewed. The 100 patients were equally divided into a routine treatment group and interventional group according to the order of admission. The routine treatment group received conventional rehabilitation training, and the interventional group received remote home management combined with Feng's spinal manipulation. The Oswestry disability index (ODI) and straight leg raising test were adopted for the assessment of the degrees of dysfunction and straight leg raising angles of the two groups after intervention. The curative effects of the two rehabilitation programs were evaluated.

Results

Compared with the routine treatment group, the interventional group had a remarkably higher excellent and good rate (P < 0.05), a significantly lower average ODI score after intervention (P < 0.001), notably higher straight leg raising angle, surface AEMG (average electromyogram) during stretching and tenderness threshold after intervention (P < 0.001), markedly lower muscular tension, surface AEMG during buckling, and flexion-extension relaxation ratio (FRR; (P < 0.001)), and much higher quality of life scores after intervention (P < 0.001).

Conclusion

The remote home management combined with Feng's spinal manipulation, as a reliable method to improve the quality of life and the back muscular strength of the elderly patients with LDH, can substantially increase the straight leg raising angle and reduce the degree of dysfunction. Further study is conducive to establishing a better solution for the patients with LDH.

Machine Learning Approach in Predicting Clinically Significant Improvements After Surgery in Patients with Cervical Ossification of the Posterior Longitudinal Ligament

STUDY DESIGN

A retrospective analysis of prospectively collected data.

OBJECTIVE

This study aimed to create a prognostic model for surgical outcomes in patients with cervical ossification of the posterior longitudinal ligament (OPLL) using machine learning (ML).

SUMMARY OF BACKGROUND DATA

Determining surgical outcomes helps surgeons provide prognostic information to patients and manage their expectations. ML is a mathematical model that finds patterns from a large sample of data and makes predictions outperforming traditional statistical methods.

METHODS

Of 478 patients, 397 and 370 patients had complete follow-up information at 1 and 2 years, respectively, and were included in the analysis. A minimal clinically important difference (MCID) was defined as an acquired Japanese Orthopedic Association (JOA) score of ≥2.5 points, after which a ML model that predicts whether MCID can be achieved 1 and 2 years after surgery was created. Patient background, clinical symptoms, and imaging findings were used as variables for analysis. The ML model was created using LightGBM, XGBoost, random forest, and logistic regression, after which the accuracy and area under the receiver-operating characteristic curve (AUC) were calculated.

RESULTS

The mean JOA score was 10.3 preoperatively, 13.4 at 1 year after surgery, and 13.5 at 2 years after surgery. XGBoost showed the highest AUC (0.72) and high accuracy (67.8) for predicting MCID at 1 year, whereas random forest had the highest AUC (0.75) and accuracy (69.6) for predicting MCID at 2 years. Among the included features, total preoperative JOA score, duration of symptoms, body weight, sensory function of the lower extremity sub-score of the JOA, and age were identified as having the most significance in most of ML models.

CONCLUSION

Constructing a prognostic ML model for surgical outcomes in patients with OPLL is feasible, suggesting the potential application of ML for predictive models of spinal surgery.Level of Evidence: 4.

Identification and Therapeutic Outcome Prediction of Cervical Spondylotic Myelopathy Based on the Functional Connectivity From Resting-State Functional MRI Data: A Preliminary Machine Learning Study

Currently, strategies to diagnose patients and predict neurological recovery in cervical spondylotic myelopathy (CSM) using MR images of the cervical spine are urgently required. In light of this, this study aimed at exploring potential preoperative brain biomarkers that can be used to diagnose and predict neurological recovery in CSM patients using functional connectivity (FC) analysis of a resting-state functional MRI (rs-fMRI) data. Two independent datasets, including total of 53 patients with CSM and 47 age- and sex-matched healthy controls (HCs), underwent the preoperative rs-fMRI procedure. The FC was calculated from the automated anatomical labeling (AAL) template and used as features for machine learning analysis. After that, three analyses were used, namely, the classification of CSM patients from healthy adults using the support vector machine (SVM) within and across datasets, the prediction of preoperative neurological function in CSM patients via support vector regression (SVR) within and across datasets, and the prediction of neurological recovery in CSM patients via SVR within and across datasets. The results showed that CSM patients could be successfully identified from HCs with high classification accuracies (84.2% for dataset 1, 95.2% for dataset 2, and 73.0% for cross-site validation). Furthermore, the rs-FC combined with SVR could successfully predict the neurological recovery in CSM patients. Additionally, our results from cross-site validation analyses exhibited good reproducibility and generalization across the two datasets. Therefore, our findings provide preliminary evidence toward the development of novel strategies to predict neurological recovery in CSM patients using rs-fMRI and machine learning technique.

Mid- and Long-Term Follow-Up Efficacy Analysis of 3D-Printed Interbody Fusion Cages for Anterior Cervical Discectomy and Fusion

OBJECTIVE

To evaluate the safety and stability of 3D-printed interbody fusion cages (3D-printed cages) in anterior cervical discectomy and fusion (ACDF) by investigating the mid- and long-term follow-up outcomes.

METHODS

In this prospective study, the clinical data of 30 patients with CSM admitted to the Second Hospital of Shanxi Medical University from May 2012 to May 2014 were analyzed. The cohort comprised 18 males and 12 females with an average age of 60.22 ± 3.2 years. All patients were examined by X-ray, CT and MRI before the operation. A total of 30 cases of CSM were treated by ACDF with 3D printed cage implantation. Mid- and long-term follow-ups were performed after the surgery. Clinical efficacy was evaluated by comparing the JOA score, SF-36 score, change in neurological function, cervical curvature index (CCI), vertebral intervertebral height (VIH) and fusion rate before the operation, 6 months after the operation, and at the last follow-up.

RESULTS

Two of the 30 patients were lost to follow-up. The remaining patients were followed up for 48-76 (65.23 ± 3.54) months. The patients recovered satisfactorily with a significant clinical effect. The JOA score increased meanfully and the improvement rate was 89.4% at the final follow-up. The SF-36 score increased significantly from pre- to postoperatively. The height of the intervertebral space at the last follow-up was not statistically significantly different from that at 6 months after surgery (P > 0.05), showing that the height of the intervertebral space did not change much and the severity of cage subsidence (CS) decreased. The CCI improved from pre- to postoperatively. The CCI did not change much from the 6-month follow-up to the last follow-up. and the cage rate (CR) was 100% at the 6-month and last follow-ups. No severe complications, such as spinal cord injury, esophageal fistula, cerebrospinal fluid leakage, cervical hematoma or wound infection, occurred in any of the patients.

CONCLUSION

The clinical and radiological results show that the application of 3D-printed cages in ACDF can significantly relieve symptoms. Moreover, 3D-printed cages can restore the curvature of the cervical spine, effectively maintain the intervertebral height for a long time, and prevent complications related to postoperative subsidence.

The patient acceptable symptom state for the Oswestry Disability Index following single-level lumbar fusion for degenerative spondylolisthesis

BACKGROUND CONTEXT

The patient acceptable symptom state (PASS) is a valuable tool for interpreting patient-reported outcomes. Previous studies have attempted to define the PASS in a heterogenous cohort with various lumbar spinal disorders and surgical procedures.

PURPOSE

We aimed to determine the PASS threshold for the Oswestry Disability Index (ODI) specifically for patients undergoing lumbar fusion for spondylolisthesis-associated functional disability.

STUDY DESIGN

Retrospective review of prospectively collected registry data.

PATIENT SAMPLE

There were 692 patients who underwent primary single-level minimally invasive transforaminal lumbar interbody fusion for degenerative spondylolisthesis between 2006 and 2014.

OUTCOME MEASURES

The ODI was collected pre-operatively, at 6 months and 2 years postoperatively. An anchor question was adapted from the NASS questionnaire, "How would you rate the overall results of your treatment?" while a validation question was taken from the same questionnaire, "Has the surgery for your back condition met your expectations so far?"

METHODS

Responses to the anchor question were used to determine whether a PASS was achieved. Receiver operating characteristics curve analysis was performed to assess the ability of the ODI to discriminate between an acceptable/unacceptable symptom state as well as to define PASS thresholds. Sensitivity analyses were performed for different follow-up periods (6 months, 2 years), subgroups (by age, gender, BMI, and comorbidity burden), baseline ODI tertiles, and an alternate definition of PASS.

RESULTS

In total, 529 of 692 (76%) patients completed 2-year follow-up, of which, 89% considered their symptom state to be acceptable. Areas under the curve (AUC) ranged from 0.81 to 0.90 for all receiver operating characteristics analyses, indicating that the ODI had an excellent discriminative ability. The PASS threshold was ≤18.09 at 6 months (AUC 0.81, sensitivity 77%, specificity 72%) and ≤15.27 at 2 years (AUC 0.86, sensitivity 79%, specificity 79%). These thresholds proved to be robust in the sensitivity analyses, showing minimal variation across different patient subgroups and baseline score tertiles.

CONCLUSIONS

Patients with an ODI of ≤15.27 can be considered to have achieved a PASS after lumbar fusion for degenerative spondylolisthesis. These findings will help surgeons to contextualize a patient's functional recovery after lumbar spine surgery and enable researchers to define clinically relevant benchmarks when designing trials utilizing the ODI.

Validity of the Japanese core outcome measures index (COMI)-neck for cervical spine surgery: a prospective cohort study

PURPOSE

To investigate the psychometric properties of the Japanese version of the Core Outcome Measures Index-Neck (COMI-Neck) in patients undergoing cervical spine surgery.

METHODS

A total of 177 patients undergoing cervical spine surgery for spinal disorders from April to December 2017 were enrolled. Patient-reported outcomes (PROs) included EuroQOL, Neck Disability Index, and treatment satisfaction. To address whether the questionnaire's scores relate to other outcomes based on a predefined hypothesis, the correlations between the COMI-Neck and the other PROs were measured (Spearman's rank correlation coefficients). The minimum clinically important difference (MCID) of the COMI summary score was calculated using the receiver operating characteristic (ROC) curve with a 7-point Likert scale of satisfaction with the treatment results. To assess reproducibility, another group of 59 volunteers with chronic neck pain were asked to reply to the COMI-Neck twice with an interval of 7-14 days.

RESULTS

The COMI summary score showed no floor or ceiling effects preoperatively or postoperatively. Each of the COMI domains and the COMI summary score correlated to the hypothesized extent with the scores of the reference questionnaires (ρ = 0.40-0.79). According to the ROC curve with satisfaction (including "very satisfied" and "satisfied"), the area under the curve and MCID of the COMI summary score were 0.78 and 2.1. The intraclass correlation coefficient and the minimum detectable change (MDC 95%) of the COMI summary score were 0.97 and 0.77.

CONCLUSION

The Japanese version of the COMI-Neck is valid and reliable for Japanese-speaking patients with cervical spinal disorders.

Baseline severity of myelopathy predicts neurological outcomes after posterior decompression surgery for cervical spondylotic myelopathy: a retrospective study

STUDY DESIGN

Retrospective multicenter study.

OBJECTIVES

To identify the usefulness of the baseline severity of myelopathy for predicting surgical outcomes for cervical spondylotic myelopathy (CSM).

SETTING

Seventeen institutions in Japan.

METHODS

This study included 675 persons with CSM who underwent posterior decompression. According to baseline severity, the individuals were divided into the mild (Japanese Orthopaedic Association [JOA] score ≥ 14.5), moderate (JOA score = 10.5-14), and severe (JOA score ≤ 10) groups. Surgical outcomes and clinical variables were compared between the groups. Logistic regression analysis was used to develop a prediction model for unsatisfactory symptom state (postoperative JOA score ≤ 14, residual moderate or severe myelopathy).

RESULTS

The mean (±standard deviation) age was 67 ± 12 years. The participants in the severe group were older than those in the mild group. Postoperative JOA scores were higher in the mild group than in the severe group. According to multivariate logistic regression analysis, the prediction model included preoperative JOA scores (odds ratio [OR] 0.60; 95% confidence interval [CI] 0.55-0.67) and age (OR 1.06, 95% CI 1.04-1.08). On the basis of the model, a representative combination of the thresholds to maximize the value of "sensitivity - (1 - specificity)" demonstrated a preoperative JOA score of 11.5 as a predictor of postoperative unsatisfactory symptom state in people around the mean age of the study cohort (67 years).

CONCLUSIONS

The combination of the baseline severity of myelopathy and age can predict postoperative symptom states after posterior decompression surgery for CSM.

Predictors of Outcomes After Single-level Anterior Cervical Discectomy and Fusion for Cervical Spondylotic Myelopathy: A Multivariate Analysis

STUDY DESIGN

This was a retrospective study that was carried out using prospectively collected registry data.

OBJECTIVE

The objective of this study was to identify preoperative predictors of outcomes after anterior cervical discectomy and fusion (ACDF) for cervical spondylotic myelopathy.

SUMMARY OF BACKGROUND DATA

Proper patient selection is paramount to achieving good surgical results. Identifying predictors of outcomes may aid surgical decision-making and facilitate counseling of patients to manage expectations.

METHODS

Prospectively collected registry data of 104 patients who underwent single-level ACDF for cervical spondylotic myelopathy were reviewed. Outcomes assessed at 2 years were the presence of residual neck pain/arm pain (AP), and attainment of a minimal clinically important difference (MCID) for Neck Disability Index (NDI), Japanese Orthopaedic Association (JOA) score, and Physical Component Score (PCS) of SF-36, as well as patient satisfaction, fulfilment of expectations, willingness to undergo same surgery again, return to work (RTW), and return to function (RTF). Receiver operating characteristic curves and multivariate stepwise logistical regression were performed to identify independent predictors of each outcome using 22 covariates including demographics, comorbidities, and preoperative disease state.

RESULTS

Lower preoperative NDI was predictive of the absence of residual neck pain/AP at 2 years. Higher preoperative JOA score was predictive of MCID attainment for PCS, satisfaction, expectation fulfilment, willingness to undergo the same surgery for same condition, and RTF. Poorer preoperative scores of NDI, JOA, and PCS were predictors of attaining MCID of the respective scores. Older patients were less likely to attain MCID for JOA. Higher preoperative AP was a risk factor for unsuccessful RTW.

CONCLUSIONS

In general, the preoperative JOA score was the best predictor of outcomes after ACDF. A preoperative JOA cutoff value of 9.25-10.25 predicted satisfaction, expectation fulfilment, willingness to undergo same surgery, and RTF with at least 70% sensitivity and 50% specificity. These findings may aid surgeons in identifying patients at risk of a poor outcome and guide preoperative counseling to establish realistic expectations of the surgical outcome.

LEVEL OF EVIDENCE

Level III-Non-randomized controlled cohort/follow-up study.

Residual numbness of the upper extremity after cervical surgery in patients with cervical spondylotic myelopathy

OBJECTIVE

Although numbness is one of the chief complaints of patients with cervical spondylotic myelopathy (CSM), preoperative factors relating to residual numbness of the upper extremity (UE) and impact of the outcomes on cervical surgery are not well established. The authors hypothesized that severe preoperative UE numbness could be a risk factor for residual UE numbness after surgery and that the residual UE numbness could have a negative impact on postoperative outcomes. Therefore, this study aimed to identify the preoperative factors that are predictive of residual UE numbness after cervical surgery and demonstrate the effects of residual UE numbness on clinical scores and radiographic parameters.

METHODS

The study design was a retrospective cohort study. The authors analyzed data of 103 patients who underwent cervical laminoplasty from January 2012 to December 2014 and were followed up for more than 2 years postoperatively. The patients were divided into two groups: the severe residual-numbness group (postoperative visual analog scale [VAS] score for UE numbness > 40 mm) and the no/mild residual-numbness group (VAS score ≤ 40 mm). The outcome measures were VAS score, Japanese Orthopaedic Association scores for cervical myelopathy, physical and mental component summaries of the 36-Item Short-Form Health Survey (SF-36), radiographic film parameters (C2-7 sagittal vertical axis, range of motion, C2-7 lordotic angle, and C7 slope), and MRI findings (severity of cervical canal stenosis, snake-eye appearance, severity of foraminal stenosis). Following univariate analysis, which compared the preoperative factors between groups, the variables with p values < 0.1 were included in the multivariate linear regression analysis. Additionally, the changes in clinical scores and radiographic parameters after 2 years of surgery were compared using a mixed-effects model.

RESULTS

Among 103 patients, 42 (40.8%) had residual UE numbness. In the multivariate analysis, sex and preoperative UE pain were found to be independent variables correlating with residual UE numbness (p = 0.017 and 0.046, respectively). The severity of preoperative UE numbness did not relate to the residual UE numbness (p = 0.153). The improvement in neck pain VAS score and physical component summary of the SF-36 was significantly low in the severe residual-numbness group (p < 0.001 and 0.040, respectively).

CONCLUSIONS

Forty-one percent of the CSM patients experienced residual UE numbness for at least 2 years after cervical posterior decompression surgery. Female sex and preoperative severe UE pain were the predictive factors for residual UE numbness. The patients with residual UE numbness showed less improvement of neck pain and lower physical status compared to the patients without numbness.

Prediction of outcome following laminoplasty of cervical spondylotic myelopathy: Focus on the minimum clinically important difference

The minimum clinically important difference (MCID) of the Japanese Orthopaedic Association (JOA) score has been reported to be around 2.5 points in cervical myelopathy. This study sought to define significant predictive factors on achieving the MCID following laminoplasty in a large series of patients with cervical spondylotic myelopathy (CSM). A total of 485 consecutive patients with CSM (295 males and 190 females; mean age: 67.0 years; age range: 42-91 years) who underwent laminoplasty were prospectively enrolled. The average postoperative follow-up period was 26.6 months (range: 12-66 months). We calculated the achieved JOA score. The relationships between outcomes and various clinical and imaging predictors including comorbidity and quantitative performance tests were examined. Logistic regression analysis was conducted to identify the predictors correlated with a JOA score of 2.5 points or more. Clinically meaningful gains were exhibited in 299 patients (61.6%) with a JOA score of ≥2.5 points, whereas 186 patients (38.4%) achieved a JOA score of <2.5 points. Univariate logistic regression analysis showed the predictive factors with a shorter duration of CSM symptoms, lower preoperative JOA scores, absence of hypertension, no use of anticoagulant/antiplatelet agents, and nonsmoking status. Multivariate logistic regression analysis determined that the duration of CSM symptoms (odds ratio: 0.771, 95% confidence interval: 0.705-0.844; p < 0.01) was the only significant predictive factor for achieving JOA scores of ≥2.5 points. An important predictor of MCID achievement following laminoplasty was shorter duration of CSM symptoms.

Determination of the patient acceptable symptom state for the Japanese Orthopaedic Association Score in patients undergoing anterior cervical discectomy and fusion for cervical spondylotic myelopathy

BACKGROUND CONTEXT

The patient acceptable symptom state (PASS) has gained attention as a valuable interpretation tool in spine research. While the PASS for the Japanese Orthopaedic Association (JOA) score has been recently proposed, previous analyses demonstrated a weak discriminative ability for the suggested threshold.

PURPOSE

To define the PASS for the JOA score in patients undergoing anterior cervical discectomy and fusion (ACDF) for cervical spondylotic myelopathy (CSM).

STUDY DESIGN

Retrospective review of prospectively collected registry data.

PATIENT SAMPLE

378 patients who underwent ACDF for cervical myelopathy between 2005 and 2014.

OUTCOME MEASURES

The main outcome measure was the JOA score. The PASS anchor question was adapted from the NASS questionnaire, "How would you rate the overall results of your treatment?" and the validation question was adapted from same questionnaire, "Has the surgery for your neck condition met your expectation so far?"

METHODS

Patients were assessed preoperatively, 6 months and 2 years postoperatively using the JOA. Responses to the anchor question were dichotomized and used as the external criterion in receiver operating characteristics (ROC) analysis to define thresholds on the JOA that corresponded to a PASS at 2 years postoperatively. Sensitivity analyses were carried out for various subgroups (based on age, gender, body mass index, comorbidities), preoperative myelopathy severity, time of follow-up (6 months and 2 years) and an alternate definition of PASS.

RESULTS

Of the 378 patients, 312 (83%) completed 2-year follow-up, of which, 78.5% reported their current state as acceptable. The areas under the curve (AUC) for the ROCs were 0.72 to 0.83 for all analyses, indicating a good discriminative ability of the JOA when assessing if a satisfactory state was attained. The PASS threshold was ≥13.25 points at 6 months (AUC 0.74, sensitivity 78%, specificity 59%) and ≥14.25 points at 2 years (AUC 0.76, sensitivity 74%, specificity 66%). Sensitivity analyses revealed that the 14.25-point threshold on the JOA was robust. PASS responders were approximately 6 times more likely to be satisfied (adjusted OR 6.18, 95% CI 2.87-13.30) and 8 times more likely to have their expectation fulfilled (adjusted OR 8.23, 95% CI 3.81-17.77) compared with non-responders.

CONCLUSIONS

This study validates the PASS threshold of 14.25 on the JOA in a robust analysis of a large cohort undergoing ACDF. This knowledge will enable clinicians to identify patients who have attained a satisfactory functional status after surgery for CSM and allow researchers to interpret studies utilizing the JOA from a patient-centered perspective.