Differences in Patient-Reported Outcomes Between Anterior and Posterior Approaches for Treatment of Cervical Spondylotic Myelopathy: A Quality Outcomes Database Analysis

Comparison of anterior and posterior approaches for functional improvement in cervical myelopathy: A systematic review and meta-analysis of 33,025 patients

Background

Cervical myelopathy is caused by pressure on the spinal cord in the neck, leading to pain, numbness, and balance issues. Surgery aims to decompress the spinal cord, with different approaches; anterior, posterior, or both depending on specifies. This systematic review and meta-analysis aimed to compare the risks and benefits of anterior and posterior surgical techniques.

Methods

Adhering to the PRISMA guidelines, we conducted a systematic search across the databases including PubMed, Scopus, and Web of Science for studies comparing anterior and posterior surgical approaches for cervical myelopathy. Studies that met our predefined inclusion criteria were selected by 2 independent reviewers. The methodological quality of the selected studies was assessed using NOS and Rob-2 tools and analysis was done using the Review Manager tool. One RCT and 22 cohort studies including 33,025 patients were included in the analysis.

Results

The anterior approach was associated with better neurological recovery and a greater improvement in Cobb's angle with MD of 4.18 (95%CI: 0.38, 7.91, p=.03), and 6.91 (95%CI: 1.85, 11.97, p=.007), respectively. The anterior approach showed a statistically significant decrease in VAS, and NDI scales with MD of -0.44 (95%CI: -0.75, -0.12, p=.007), and -1.91 (95%CI: -3.74, -0.09, p=.04), respectively as compared to posterior approach.

Conclusions

Studies suggest that an anterior approach for cervical myelopathy may improve nerve function, correct spinal curvature more effectively, and lead to fewer complications, less pain, reduced blood loss, and a shorter hospital stay compared to a posterior approach.

Comparison of outcomes after anterior versus posterior surgery for degenerative cervical myelopathy: a pooled analysis of individual patient data

BACKGROUND CONTEXT

Uncertainty exists regarding the optimal surgical approach to treat patients with degenerative cervical myelopathy (DCM). This uncertainty is particularly marked for patients with mild DCM who may be more sensitive to different management techniques.

PURPOSE

To determine the effect of surgical approach on one-year outcomes for DCM.

STUDY DESIGN/SETTING

Individual patient data meta-analysis of 3 independent, prospective, multicentre clinical trials (ie, CSM-North America, CSM-International, CSM-Protect) that enrolled patients between 2005 and 2018 in academic hospitals, with 1 yr follow up. Statistical analysis was performed from September 13, 2023 to April 2, 2024.

PATIENT SAMPLE

From a total of 1047 adult subjects with DCM, 980 met the eligibility criteria who were surgical candidates with symptomatic and radiologically-evidenced DCM with no prior cervical surgery.

OUTCOMES MEASURES

The primary endpoint was change in 36-Item Short Form Health Survey Physical Component Summary score (SF36-PCS; minimum clinically important difference [MCID]=4) at 1 yr compared to preoperatively. Secondary endpoints were change in modified Japanese Orthopedic Association (mJOA; MCID=2) score, Neck Disability Index (NDI; MCID=15) score, SF36 Mental Component Summary (SF36-MCS; MCID=4) score, and postoperative complications.

METHODS

Two comparison cohorts were created: i) anterior surgery and ii) posterior surgery. Mean differences (MD) of outcomes with 95% confidence intervals (CI) were estimated using one-stage covariate-adjusted hierarchical mixed-effects meta-analyses with study and treatment exposure as random effects. A priori subgroup analysis in mild DCM patients (mJOA=15-17) was conducted.

RESULTS

The mean patient age was 56.9 years (SD=11.4), with 38.7% that identified as female. 560 patients (57.1%) received anterior cervical decompressive surgery for DCM. Patients who had anterior decompressive surgery experienced greater improvements in quality of life and disability at 1 yr follow-up than those who underwent posterior decompressive surgery in SF36-PCS (MD=1.57 [95% CI 0.11-3.03], p=.0348) and NDI (MD=3.32 [95% CI 0.58-6.05], p=.017). Dysphagia was more likely after anterior surgery. Pseudoarthrosis and wound infections were more likely after posterior surgery. In a subgroup of patients with mild DCM, patients who underwent anterior decompressive surgery experienced even greater improvements in SF36-PCS (MD=5.45 [95% CI 1.73-9.18], p=.0042), NDI (MD=10.37 [95%CI 3.43-17.31], p=.0035), and mJOA (MD=0.95 [95% CI 0.12-1.77], p=.0238; MCID=1) than posterior surgery patients.

CONCLUSION

Anterior surgical decompression for DCM is associated with greater improvements in 1 yr patient-reported quality of life and disability than posterior surgical decompression. These results may assist clinicians in driving complex management decisions.

The Effects of Peri-Operative Adverse Events on Clinical and Patient-Reported Outcomes After Surgery for Degenerative Cervical Myelopathy: An Observational Cohort Study from the Canadian Spine Outcomes and Research Network

BACKGROUND AND OBJECTIVES

There is a lack of data examining the effects of perioperative adverse events (AEs) on long-term outcomes for patients undergoing surgery for degenerative cervical myelopathy. We aimed to investigate associations between the occurrence of perioperative AEs and coprimary outcomes: (1) modified Japanese Orthopaedic Association (mJOA) score and (2) Neck Disability Index (NDI) score.

METHODS

We analyzed data from 800 patients prospectively enrolled in the Canadian Spine Outcomes and Research Network multicenter observational study. The Spine AEs Severity system was used to collect intraoperative and postoperative AEs. Patients were assessed at up to 2 years after surgery using the NDI and the mJOA scale. We used a linear mixed-effect regression to assess the influence of AEs on longitudinal outcome measures as well as multivariable logistic regression to assess factors associated with meeting minimal clinically important difference (MCID) thresholds at 1 year.

RESULTS

There were 167 (20.9%) patients with minor AEs and 36 (4.5%) patients with major AEs. The occurrence of major AEs was associated with an average increase in NDI of 6.8 points (95% CI: 1.1-12.4, P = .019) and reduction of 1.5 points for mJOA scores (95% CI: -2.3 to -0.8, P < .001) up to 2 years after surgery. Occurrence of major AEs reduced the odds of patients achieving MCID targets at 1 year after surgery for mJOA (odds ratio 0.23, 95% CI: 0.086-0.53, P = .001) and for NDI (odds ratio 0.34, 95% CI: 0.11-0.84, P = .032).

CONCLUSION

Major AEs were associated with reduced functional gains and worse recovery trajectories for patients undergoing surgery for degenerative cervical myelopathy. Occurrence of major AEs reduced the probability of achieving mJOA and NDI MCID thresholds at 1 year. Both minor and major AEs significantly increased health resource utilization by reducing the proportion of discharges home and increasing length of stay.

Is Upper Extremity or Lower Extremity Function More Important for Patient Satisfaction? An Analysis of 24-Month Outcomes from the QOD Cervical Spondylotic Myelopathy Cohort

STUDY DESIGN

Retrospective analysis of a prospective, multicenter registry.

OBJECTIVE

To assess whether upper or lower limb mJOA improvement more strongly associates with patient satisfaction after surgery for cervical spondylotic myelopathy (CSM).

SUMMARY OF BACKGROUND DATA

The modified Japanese Orthopaedic Association (mJOA) is commonly used to assess functional status in patients with CSM. Patients present with upper and/or lower extremity dysfunction, and it is unclear whether improvement in one and/or both symptoms drives postoperative patient satisfaction.

METHODS

This study utilizes the prospective Quality Outcomes Database (QOD) CSM data set. Clinical outcomes included mJOA and North American Spine Society (NASS) satisfaction. The upper limb mJOA score was defined as upper motor plus sensory mJOA, and the lower limb mJOA as lower motor plus sensory mJOA. Ordered logistic regression was used to determine whether upper or lower limb mJOA was more closely associated with NASS satisfaction, adjusting for other covariates.

RESULTS

Overall, 1141 patients were enrolled in the QOD CSM cohort. In all, 780 had both preoperative and 24-month mJOA scores, met inclusion criteria, and were included for analysis. The baseline mJOA was 12.1±2.7, and postoperatively, 85.6% would undergo surgery again (NASS 1 or 2, satisfied). Patients exhibited mean improvement in both upper (baseline:3.9±1.4 vs. 24 mo:5.0±1.1, P<0.001) and lower limb mJOA (baseline:3.9±1.4 vs. 24 mon:4.5±1.5, P<0.001); however, the 24-month change in the upper limb mJOA was greater (upper:1.1±1.6 vs. lower:0.6±1.6, P<0.001). Across 24-month NASS satisfaction, the baseline upper and lower limb mJOA scores were similar (pupper=0.28, plower=0.092). However, as satisfaction decreased, the 24-month change in upper and lower limb mJOA decreased as well (pupper<0.001, plower<0.001). Patients with NASS scores of 4 (lowest satisfaction) did not demonstrate significant differences from baseline in upper or lower limb mJOA (P>0.05). In ordered logistic regression, NASS satisfaction was independently associated with upper limb mJOA improvement (OR=0.81; 95% CI: 0.68-0.97; P=0.019) but not lower limb mJOA improvement (OR=0.84; 95% CI: 0.70-1.0; P=0.054).

CONCLUSIONS

As the magnitude of upper and lower mJOA improvement decreased postoperatively, so too did patient satisfaction with surgical intervention. Upper limb mJOA improvement was a significant independent predictor of patient satisfaction, whereas lower limb mJOA improvement was not. These findings may aid preoperative counseling, stratified by patients' upper and lower extremity treatment expectations.

LEVEL OF EVIDENCE

Level-III.

Anterior vs Posterior Surgery for Patients With Degenerative Cervical Myelopathy: An Observational Study From the Canadian Spine Outcomes and Research Network

BACKGROUND AND OBJECTIVES

The advantages and disadvantages of anterior vs posterior surgical approaches for patients with progressive degenerative cervical myelopathy (DCM) remain uncertain. Our primary objective was to evaluate patient-reported disability at 1 year after surgery. Our secondary objectives were to evaluate differences in patient profiles selected for each approach in routine clinical practice and to compare neurological function, neck and arm pain, health-related quality of life, adverse events, and rates of reoperations.

METHODS

We analyzed data from patients with DCM who were enrolled in an ongoing multicenter prospective observational cohort study. We controlled for differences in baseline characteristics and numbers of spinal levels treated using multivariable logistic regression. Adverse events were collected according to the Spinal Adverse Events Severity protocol.

RESULTS

Among 559 patients, 261 (47%) underwent anterior surgery while 298 (53%) underwent posterior surgery. Patients treated posteriorly had significantly worse DCM severity and a greater number of vertebral levels involved. After adjusting for confounders, there was no significant difference between approaches for odds of achieving the minimum clinically important difference for the Neck Disability Index (odds ratio 1.23, 95% CI 0.82 to 1.86, P = .31). There was also no significant difference for change in modified Japanese Orthopedic Association scores, and differences in neck and arm pain and health-related quality of life did not exceed minimum clinically important differences. Patients treated anteriorly experienced greater rates of dysphagia, whereas patients treated posteriorly experienced greater rates of wound complications, neurological complications, and reoperations.

CONCLUSION

Patients selected for posterior surgery had worse DCM and a greater number of vertebral levels involved. Despite this, anterior and posterior surgeries were associated with similar improvements in disability, neurological function, pain, and quality of life. Anterior surgery had a more favorable profile of adverse events, which suggests it might be a preferred option when feasible.

Impact of Preoperative Frailty on Outcomes in Patients with Cervical Spondylotic Myelopathy Undergoing Anterior vs. Posterior Cervical Surgery

Introduction: Frailty has been shown to negatively influence patient outcomes across many disease processes, including in the cervical spondylotic myelopathy (CSM) population. The aim of this study was to assess the impact that frailty has on patients with CSM who undergo anterior cervical discectomy and fusion (ACDF) or posterior cervical decompression and fusion (PCDF). Materials and Methods: A retrospective cohort study was performed using the 2016-2019 national inpatient sample. Adult patients (≥18 years old) undergoing ACDF only or PCDF only for CSM were identified using ICD codes. The patients were categorized based on receipt of ACDF or PCDF and pre-operative frailty status using the 11-item modified frailty index (mFI-11): pre-Frail (mFI = 1), frail (mFI = 2), or severely frail (mFI ≥ 3). Patient demographics, comorbidities, operative characteristics, perioperative adverse events (AEs), and healthcare resource utilization were assessed. Multivariate logistic regression analyses were used to identify independent predictors of extended length of stay (LOS) and non-routine discharge (NRD). Results: A total of 37,990 patients were identified, of which 16,665 (43.9%) were in the pre-frail cohort, 12,985 (34.2%) were in the frail cohort, and 8340 (22.0%) were in the severely frail cohort. The prevalence of many comorbidities varied significantly between frailty cohorts. Across all three frailty cohorts, the incidence of AEs was greater in patients who underwent PCDF, with dysphagia being significantly more common in patients who underwent ACDF. Additionally, the rate of adverse events significantly increased between ACDF and PCDF with respect to increasing frailty (p < 0.001). Regarding healthcare resource utilization, LOS and rate of NRD were significantly greater in patients who underwent PCDF in all three frailty cohorts, with these metrics increasing with frailty in both ACDF and PCDF cohorts (LOS: p < 0.001); NRD: p < 0.001). On a multivariate analysis of patients who underwent ACDF, frailty and severe frailty were found to be independent predictors of extended LOS [(frail) OR: 1.39, p < 0.001; (severely frail) OR: 2.25, p < 0.001] and NRD [(frail) OR: 1.49, p < 0.001; (severely frail) OR: 2.22, p < 0.001]. Similarly, in patients who underwent PCDF, frailty and severe frailty were found to be independent predictors of extended LOS [(frail) OR: 1.58, p < 0.001; (severely frail) OR: 2.45, p < 0.001] and NRD [(frail) OR: 1.55, p < 0.001; (severely frail) OR: 1.63, p < 0.001]. Conclusions: Our study suggests that preoperative frailty may impact outcomes after surgical treatment for CSM, with more frail patients having greater health care utilization and a higher rate of adverse events. The patients undergoing PCDF ensued increased health care utilization, compared to ACDF, whereas severely frail patients undergoing PCDF tended to have the longest length of stay and highest rate of non-routine discharge. Additional prospective studies are necessary to directly compare ACDF and PCDF in frail patients with CSM.

Response rates in clinical quality registries and databases that collect patient reported outcome measures: a scoping review

BACKGROUND

Patient Reported Outcome Measures (PROMs) are being increasingly introduced in clinical registries, providing a personal perspective on the expectations and impact of treatment. The aim of this study was to describe response rates (RR) to PROMs in clinical registries and databases and to examine the trends over time, and how they change with the registry type, region and disease or condition captured.

METHODS

We conducted a scoping literature review of MEDLINE and EMBASE databases, in addition to Google Scholar and grey literature. All English studies on clinical registries capturing PROMs at one or more time points were included. Follow up time points were defined as follows: baseline (if available), < 1 year, 1 to < 2 years, 2 to < 5 years, 5 to < 10 years and 10 + years. Registries were grouped according to regions of the world and health conditions. Subgroup analyses were conducted to identify trends in RRs over time. These included calculating average RRs, standard deviation and change in RRs according to total follow up time.

RESULTS

The search strategy yielded 1,767 publications. Combined with 20 reports and four websites, a total of 141 sources were used in the data extraction and analysis process. Following the data extraction, 121 registries capturing PROMs were identified. The overall average RR at baseline started at 71% and decreased to 56% at 10 + year at follow up. The highest average baseline RR of 99% was observed in Asian registries and in registries capturing data on chronic conditions (85%). Overall, the average RR declined as follow up time increased.

CONCLUSION

A large variation and downward trend in PROMs RRs was observed in most of the registries identified in our review. Formal recommendations are required for consistent collection, follow up and reporting of PROMs data in a registry setting to improve patient care and clinical practice. Further research studies are needed to determine acceptable RRs for PROMs captured in clinical registries.