The natural history of degeneration of the lumbar and cervical spines: a systematic review

The Degree of Cervical Intervertebral Disc Degeneration Is Associated With Denser Bone Quality of the Cervical Sub-endplate and Vertebral Body

OBJECTIVE

The relationship between cervical disc degeneration and bone quality of adjacent vertebral body remains controversial. This study aims to investigate the relationship between cervical disc degeneration and bone quality of the adjacent vertebral body and sub-endplate bone with a new MRI-based bone quality score in patients over 50 years with cervical spondylosis.

METHODS

We retrospectively reviewed 479 cervical disc segments from 131 patients. Disc degeneration at levels C3/C4-C6/C7 was graded using T2-weighted MRI. Vertebral body quality (VBQ) score and sub-endplate bone quality (EBQ) score from C3 to C7 were computed from T1-weighted MRI images. Additionally, bone mineral density (BMD) of the cervical vertebrae was measured in 52 patients using a novel phantom-less quantitative computed tomography (PL-QCT) system. The correlation between bone quality score and Pfirrmann grade was analyzed and risk factors for VBQ and EBQ were further evaluated.

RESULTS

Significant differences were found in cranial VBQ among different Pfirrmann grades, with a score of 2.55 ± 0.54 for Grade 5 discs, which was lower compared to Grades 4 (2.70 ± 0.56) (p < 0.05) and 3 (2.81 ± 0.58) (p < 0.01). Caudal VBQ for Grade 5 discs (2.43 ± 0.52) was also significantly lower than for Grade 3 discs (2.66 ± 0.54) (p < 0.01). EBQ scores decreased with increasing Pfirrmann grades. Negative correlations were observed between both cranial and caudal VBQ and EBQ scores and Pfirrmann grades. Grades 4 and 5 discs were identified as independent risk factors for decreased caudal VBQ and EBQ, whereas only Grade 5 was a significant risk factor for decreased cranial EBQ. Additionally, a moderate correlation (0.4 < R < 0.6, p < 0.05) was noted between vertebral body BMD and VBQ at each cervical level.

CONCLUSION

In individuals over 50 years with cervical spondylosis, the severity of disc degeneration was closely correlated with denser bone quality in both the caudal vertebral body and sub-endplate, as measured by VBQ and EBQ scores. These findings suggest that worsening disc degeneration is associated with increased bone density in specific areas of the cervical spine.

Patient-reported outcome of lumbar decompression with instrumented fusion for low-grade spondylolisthesis: influence of pathology and baseline symptoms

INTRODUCTION

Low-grade isthmic and degenerative spondylolisthesis (DS) of the lumbar spine are distinct pathologies but both can be treated with lumbar decompression with fusion. In a very large cohort, we compared patient-reported outcome in relation to the pathology and chief complaint at baseline.

METHODS

This was a retrospective analysis using the EUROSPINE Spine Tango Registry. We included 582 patients (age 60 ± 15 years; 65% female), divided into four groups based on two variables: type of spondylolisthesis and chief pain complaint (leg pain (LP) versus back pain). Patients completed the COMI preoperatively and up to 5 years follow-up (FU), and rated global treatment outcome (GTO). Regression models were used to predict COMI-scores at FU. Pain scores and satisfaction ratings were analysed.

RESULTS

All patients experienced pronounced reductions in COMI scores. Relative to the other groups, the DS-LP group showed between 5% and 11% greater COMI score reduction (p < 0.01 up to 2 years' FU). This group also performed best with respect to pain outcomes and satisfaction. Long-term GTO was 93% at the 5 year FU, compared with between 82% and 86% in the other groups.

CONCLUSION

Regardless of the type of spondylolisthesis, all groups experienced an improvement in COMI score after surgery. Patients with DS and LP as their chief complaint appear to benefit more than other patients. These results are the first to show that the type of the spondylolisthesis and its chief complaint have an impact on surgical outcome. They will be informative for the consent process prior to surgery and can be used to build predictive models for individual outcome.

Papain Injection Creates a Nucleotomy-like Cavity for Testing Gels in Intervertebral Discs

Biomaterials, such as hydrogels, have an increasingly important role in the development of regenerative approaches for the intervertebral disc. Since animal models usually resist biomaterial injection due to high intradiscal pressure, preclinical testing of the biomechanical performance of biomaterials after implantation remains difficult. Papain reduces the intradiscal pressure, creates cavities within the disc, and allows for biomaterial injections. But papain digestion needs time, and cadaver experiments that are limited to 24 h for measuring range of motion (ROM) cannot not be combined with papain digestion just yet. In this study, we successfully demonstrate a new organ culture approach, facilitating papain digestion to create cavities in the disc and the testing of ROM, neutral zone (NZ), and disc height. Papain treatment increased the ROM by up to 109.5%, extended NZ by up to 210.9%, and decreased disc height by 1.96 ± 0.74 mm. A median volume of 0.73 mL hydrogel could be injected after papain treatment, and histology revealed a strong loss of proteoglycans in the remaining nucleus tissue. Papain has the same biomechanical effects as known from nucleotomies or herniations and thus creates a disc model to study such pathologies in vitro. This new model can now be used to test the performance of biomaterials.

Minimally Invasive Posterior Tubular Microsurgical Approach for the Management of Symptomatic Synovial Cysts of the Lumbar and Cervical Spine

BACKGROUND

Synovial cysts are commonly associated with instability. Whether to fuse patients is a matter of controversy. Simple resection may offer favorable clinical outcomes but may come at the expense of recurrence rate. We describe our experience with the minimally invasive management of these lesions using microsurgical dissection through a tubular retractor system.

MATERIALS

A retrospective cohort study of symptomatic patients with synovial cysts treated by a minimally invasive tubular approach from 2001 to 2018 was performed. We evaluated variables such as preexisting spinal pathology, previous surgery, radiological findings, comorbidities, and secondary surgery requiring fusion. We used the visual analog scale (VAS), the Oswestry disability index (ODI), and the Macnab scale for clinical evaluation.

RESULTS

There were 35 patients with a mean age of 63 years. The mean duration of symptoms before surgery was 195 weeks. Axial pain was present in 77.1% of cases; radiculopathy was the main symptom in 94.3% of cases. The most frequent site was L4-L5 (62.8%). Presenting comorbidities were lumbar stenosis (28.6% of patients), spondylolisthesis (8.6%), and facet hypertrophy (31.4%). Mean surgical time was 143 minutes (range, 55-360 minutes). The mean hospital stay was 2 days, ranging from 1 to 5 days. No complications were encountered as a consequence of the surgical procedure. All patients showed neurophysiological improvement after surgical intervention. A total of 34 patients (97.14%) showed clinical improvement at the end of follow-up, averaging 17 months and ranging from 1 to 60 months, 28 patients (80%) had good to excellent Macnab outcomes, 6 patients (17.14%) were rated as fair, and 1 (2.86%) patient had a poor Macnab outcome. Radicular VAS significantly changed (P < .05) from a preoperative mean of 8.23 ± 1.24 to a postoperative mean of 2.23 ± 1.94. ODI significantly decreased (P < .05) from a preoperative of mean of 41.02 ± 12.56 to a postoperative of mean of 11.82 ± 10.56. We performed fusion at initial surgery in 37.1% of cases; however, 3 more patients required secondary fusion at follow-up.

CONCLUSION

Our series corroborates the prior literature with a low incidence of synovial cysts in the cervical spine and none in the thoracic spine. The present work shows the efficacy of minimally invasive surgery in the treatment of these lesions. Synovial cysts were associated with instability, ultimately requiring fusion in the majority of patients. The authors' study includes a large patient series with minimally invasive microsurgical decompression performed through a tubular retractor to date.

LEVEL OF EVIDENCE

3.

Impact of adjacent pre-existing disc degeneration status on its biomechanics after single-level anterior cervical interbody fusion

BACKGROUND AND OBJECTIVE

Mechanics and biology may be interconnected and amplify each other during disc degeneration. It remains unknown the influence of pre-existing disc degeneration and its impact on adjacent segment degeneration (ASD) after anterior cervical discectomy and fusion (ACDF). This study aimed to discuss the necessity of including degenerated adjacent segments in single-level ACDF surgery from a biomechanical view.

METHODS

A poroelastic C2-T1 finite element model was created and validated. A C5-C6 ACDF model was developed based on this normal model. Moderate C4-C5 disc degeneration was created by appropriately modifying the morphology and tissue material properties in this fusion model. Degenerative morphology was modeled based on Thompson's grading system and Walraevens's scoring system for cervical spine, including disc height, whole disc area, nucleus pulposus (NP) area, endplate sclerosis and curvature. Stresses in disc and endplate and loads in facet joint were computed under moment loads in the fusion models with normal and pre-existing degenerative disc condition.

RESULTS

As for the adjacent disc, the stress values in degenerative condition were 7.41%, 5% and 5.26% larger than that in normal situation during extension, axial rotation and lateral bending motion, respectively. The disc stress changes mainly stemmed from annulus fibrosus (AF) tissue, but not NP. In the endplate, stress values of degeneration status were 4.17, 4.35 and 6.06% larger than that of normal condition under axial rotation, lateral bending and extension. The facet load magnitudes of pre-existing degeneration were 11.28, 11.57, 11.78 and 11.42% greater than that of normal condition in flexion, extension, axial rotation and lateral bending motion.

CONCLUSION

Pre-existing degenerated disc experience increased biomechanical changes in adjacent segment after single-level ACDF. It may pose a long-term cumulative problem related to biomechanics in cervical spine after fusion. Before surgery, surgeons should be careful about selecting the fusion level.

The Diagnostic Value of an X-ray-based Scoring System for Degeneration of the Cervical Spine: A Reproducibility and Validation Study

Background

In interventional pain medicine, cervical facet joint (CFJ) pain is commonly treated with CFJ denervation techniques, almost automatically assuming degeneration of the CFJs as an important cause of CFJ pain. A standard cervical X‐ray is still commonly used in the clinical evaluation of patients suspected for CFJ degeneration. Although degenerative features can be visualized by different radiological imaging techniques, the relation between radiological degenerative features of the cervical spine and pain remains controversial. Paramount in order to estimate the clinical usefulness of a radiological imaging is to establish the reproducibility of the radiological scoring system. A reproducible and clinically feasible diagnostic scoring system was developed to estimate cervical degeneration on standard cervical X‐rays.

Materials and Methods

A reproducibility study for the interpretation of degenerative abnormalities on standard cervical X‐rays was performed, using a dichotomous outcome (degenerative abnormalities present Yes/No). The estimation of intervertebral disc height loss on standard cervical X‐rays was validated with computed tomography (CT) scan measurements.

Results

Five radiological degenerative features on standard cervical X‐rays (disc height loss, anterior vertebral osteophytes, posterior vertebral osteophytes, vertebral end plate sclerosis, and uncovertebral osteoarthritis) showed a substantial to excellent reproducibility (kappa value ≥ 0.60). The qualitative definition of disc height loss used in the reproducibility study showed a substantial agreement with the actual measurements of disc height loss on CT scan (kappa value = 0.69).

Conclusion

Subjective judgment of a cervical standard X‐ray is a reproducible method to demonstrate degenerative abnormalities of the cervical spine.

Dynamic Stabilization Adjacent to Fusion versus Posterior Lumbar Interbody Fusion for the Treatment of Lumbar Degenerative Disease: A Meta-Analysis

This study evaluated differences in outcome variables between dynamic stabilization adjacent to fusion (DATF) and posterior lumbar interbody fusion (PLIF) for the treatment of lumbar degenerative disease. A systematic review of PubMed, EMBASE, and Cochrane was performed. The variables of interest included clinical adjacent segment pathologies (CASPs), radiological adjacent segment pathologies (RASPs), lumbar lordosis (LL), visual analogue scale (VAS) of back (VAS-B) and leg (VAS-L), Oswestry disability index (ODI), Japanese Orthopaedic Association (JOA) score, duration of surgery (DS), estimated blood loss (EBL), complications, and reoperation rate. Nine articles identified as meeting all of the inclusion criteria. DATF was better than PLIF in proximal RASP, CASP, and ODI during 3 months follow-up, VAS-L. However, no significant difference between DATF and PLIF was found in distal RASP, LL, JOA score, VAS-B, ODI after 3 months follow-up, complication rates, and reoperation rate. These further confirmed that DATF could decrease the proximal ASP both symptomatically and radiographically as compared to fusion group; however, the influence of DATF on functional outcome was similar with PLIF. The differences between hybrid surgery and topping-off technique were located in DS and EBL in comparison with PLIF. Our study confirmed that DATF could decrease the proximal ASP both symptomatically and radiographically as compared to the fusion group; however, the influence of DATF on functional outcome was similar with PLIF. The difference between hybrid surgery and topping-off technique was not significant in treatment outcomes.

Development and characterization of an immunomodulatory and injectable system composed of collagen modified with trifunctional oligourethanes and silica

Immunomodulatory biomaterials have emerged as a promising approach to engineer wound healing. To achieve this task, the bioactivity of the biomaterials and an easy application are two key desirable characteristics. This work reports an injectable gel system containing immune cells primed for wound healing. By combining the self-assembly of type I collagen, cross-linked with trifunctional oligourethanes, and silica particle entrapment, the structured collagen network acts as a delivery vehicle for macrophages. This structured collagen network primes the macrophages for an anti-inflammatory response. Rheological measurements suggest that the mixture of liquid precursors can be safely stored at low temperatures and low pH (4 °C, pH 3) for at least one month. After pH neutralization and injection, gels with a storage modulus of 50-80 Pa are obtained in five minutes. Several immunocytochemistry and ELISA tests strongly suggest that mouse and human macrophages are stimulated by the material to up-regulate the production of anti-inflammatory cytokines, while down-regulating the production of pro-inflammatory cytokines. The injection of gel in an ex vivo inflammation model of intervertebral discs demonstrated that it is possible to transit from a pro-inflammatory to an anti-inflammatory microenvironment. Altogether, the results suggest that this gel can polarize the macrophage response and promote a surrounding anti-inflammatory microenvironment ready for injection for wound healing applications.

Crossing the Cervicothoracic Junction in Cervical Arthrodesis Results in Lower Rates of Adjacent Segment Disease Without Affecting Operative Risks or Patient-Reported Outcomes

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

To evaluate the risks and benefits of crossing the cervicothoracic junction (CTJ) in cervical arthrodesis.

SUMMARY OF BACKGROUND DATA

Whether the CTJ should be crossed in cervical arthrodesis remains up for debate. Keeping C7 as the distal end of the fusion risks adjacent segment disease (ASD) and can result in myelopathy or radiculopathy. Longer fusions are thought to increase operative risk and complexity but result in lower rates of ASD.

MATERIALS AND METHODS

Patients undergoing cervical spine fusion surgery ending at C7 or T1 with ≥1-year follow-up were included. To evaluate operative risk, estimated blood loss (EBL), operative time, and length of hospital stay were collected. To evaluate patient-reported outcomes (PROs), Neck Disability Index (NDI) and SF-12 questionnaires (PCS12 and MCS12) were obtained at follow-up. Revision surgery data were also obtained.

RESULTS

A total of 168 patients were included and divided into a C7 end-of-fusion cohort (NC7=59) and a T1 end-of-fusion cohort (NT1=109). Multivariate regression analysis adjusting for age, sex, race, surgical approach, and number of levels fused showed that EBL (P=0.12), operative time (P=0.07), and length of hospital stay (P=0.06) are not significantly different in the C7 and T1 end-of-fusion cohorts. Multivariate regression of PROs showed no significant difference in NDI (P=0.70), PCS12 (P=0.23), or MCS12 (P=0.15) between cohorts. Fisher analysis showed significantly higher revision rates in the C7 end-of-fusion cohort (7/59 for C7 vs. 2/109 for T1; odds ratio, 6.4; 95% confidence interval, 1.2-65.1; P=0.01).

CONCLUSIONS

Crossing the CTJ in cervical arthrodesis does not increase operative risk as measured by blood loss, operative time, and length of hospital stay. However, it leads to lower revision rates, likely because of the avoidance of ASD, and comparable PROs. Thus, crossing the CTJ may help prevent ASD without negatively affecting operative risk or long-term PROs.

Effect of spinal decompression on back pain in lumbar spinal stenosis: a Canadian Spine Outcomes Research Network (CSORN) study

BACKGROUND CONTEXT

Surgical decompression is usually offered for improvement of neurogenic claudication in patients with symptomatic lumbar canal stenosis. These patients often have associated low back pain (LBP) and little is known about the effect of decompression on this symptom.

PURPOSE

The goal of the present study is to specifically quantify the improvement in LBP following surgical decompression for lumbar canal stenosis and to identify factors associated with changes in LBP in this population.

STUDY DESIGN

This is a multicenter, retrospective review of consecutive spine surgery patients enrolled by the Canadian Spine Outcomes and Research Network.

PATIENT SAMPLE

Consecutive patients who underwent surgical treatment for symptomatic lumbar spine stenosis without instability between 2014 and 2017.

OUTCOME MEASURES

Change in LBP on the Numeric Rating Scale (NRS).

METHODS

Patient-reported outcomes were collected at baseline and at 3, 12, and 24 months after surgery. The primary outcome was change in LBP on the NRS. Multivariable logistic regression was used to model the relationship between the outcome and potential factors associated with achieving minimal clinical important difference in back pain using a backward selection procedure.

RESULTS

In all, 1,221 patients were included in the analysis. Mean age was 64 years and 58% were males. Baseline back pain scores were available in 1,133 patients and follow-up evaluations were available in 968/1,133 (85%) patients at 3 months, 649/903 (72%) patients at 12 months, and 331/454 (73%) at 24 months. LBP significantly improved 3 months after surgery and the improvement was sustained at 24 months (p<.001). We found that 74% of patients reached the minimal clinical important difference in back pain. Predictive factors for sustained improvement (12 and 24 months) in LBP after surgical intervention were absence of narcotic usage or compensation claims and increased severity of LBP before surgery (high NRS).

CONCLUSIONS

Alleviation of clinically significant LBP was observed at 3 months after lumbar decompression surgery for neurogenic claudication and was maintained at 12 and 24 months after surgery in the majority of patients.

Effects of Cervical Rotatory Manipulation (CRM) on Carotid Atherosclerosis Plaque in Vulnerability: A Histological and Immunohistochemical Study Using Animal Model

Background

The safety of cervical rotatory manipulation (CRM) is still controversial, especially in patients with carotid artery atherosclerosis (CAS). The study aimed to investigate the effects of CRM on carotid plaques in vulnerability.

Methods

50 rabbits were randomly divided into four groups: model rabbits with CRM [CAS-CRM (n=15)]; model rabbits without CRM [CAS (n=15)]; normal rabbits with CRM [Normal-CRM (n=10)]; and Blank-control group (n=10). CAS disease models were induced by carotid artery balloon injury combined with a high-fat diet for 12 weeks. Then, CRM technique was performed in CAS-CRM and Normal-CRM groups for 3 weeks. In the end, determination of serum level of hs-CRP and Lp-PLA2, histological analysis under HE and Masson trichromic staining, and immunohistochemical analysis with CD34 and CD68 antibody were completed in order.

Results

Carotid stenosis rates on successful model rabbits ranged from 70% to 98%. The CAS-CRM group had an increased level of hs-CRP (P<0.05), in comparison with the CAS group, whereas effects were not significant between the Normal-CRM group and Blank-control group. In comparison with the CAS group, the positive expression of CD34 and CD68 in the CAS-CRM group increased significantly (P<0.05).

Conclusion

CRM therapy may increase the vulnerability of carotid plaque in rabbits with severe CAS.

Therapeutic evaluation of acupoint stimulation with needle-scapelon on rat model of degenerative cervical intervertebral discs

Cervical spondylosis (CS), which is resulted from degeneration of cervical intervertebral disc, is a common disease seriously threatening human health and quality of life. However, there is still no effective clinic strategies for the treatment of this disease. The acupoint stimulation with needle-scalpel is a widely used approach to treat orthopedic diseases. In the present study, we evaluated the therapeutic effects of acupoint stimulation around neck with needle-scalpel on delaying the degeneration of cervical intervertebral discs and hopefully provided an approach for the precaution and early intervention of CS. We firstly established a rat model of CS by cervical static-dynamic imbalance to mimics disc degeneration and then stimulated the acupoints around neck with needle-scalpel. The cervical intervertebral disc samples were collected to measure type I and II collagen by quantitative PCR (qPCR), immunohistochemistry, and western blot. The changes in micro-structure and ultra-structure of nucleus pulposus were analyzed under the optical microscope and electron microscope respectively. Acupoint stimulation with needle-scapelon increased type I collagen production and decreased type II collagen production, and improved the micro-structure and ultra-structure of nucleus pulposus. Our results suggest that acupoint stimulation around neck with needle-scapelon could inhibit intervertebral disc degeneration through modulating the extracellular matrix collagen system and improving the changed structure of nucleus pulposus.

Postoperative MRI findings 5 years after lumbar microdiscectomy

BACKGROUND

Lumbar microdiscectomy is a common procedure with satisfactory results; however, postoperative events like progressive adjacent level degeneration and perineural fibrosis can contribute to long-term pain. The purpose of the study was to evaluate MRI changes 5 years after lumbar microdiscectomy and assess their association with clinical parameters.

MATERIALS AND METHODS

A prospective study enrolling 61 patients who underwent microdiscectomy. Changes between preoperative and postoperative MRI findings were recorded, and these findings were tested for associations with demographic, clinical and perioperative parameters. The measured imaging parameters were degeneration of the operated and adjacent discs and endplates, morphology of the disc herniation, facet joints arthritis and the presence of postoperative perineural fibrosis.

RESULTS

Statistically significant differences were found between preoperative and postoperative morphology of the operated disc, facet joints arthritis and degeneration of the operated and caudal adjacent disc. There were no differences between preoperative and postoperative disc degeneration of the superior adjacent disc and in degeneration of the operated and adjacent endplates. Postoperatively perineural fibrosis was common; however, thecal sac compression and nerve root impingement were reduced. Age at the time of surgery was the only parameter associated with postoperative changes.

CONCLUSION

Five years after microdiscectomy, several postoperative MRI changes including operated disc's morphology, facet joints arthritis and degeneration of the operated and caudal adjacent disc were shown. Taking into consideration that participants were on average middle-aged, these changes could be attributed not only to the impact of the surgery but also to the natural history of lumbar spine degeneration.

Validation of the Fusion Risk Score for Thoracic and Lumbar Spine Fusion Procedures

STUDY DESIGN

This is a retrospective cohort study.

OBJECTIVE

This study aimed to determine whether the Fusion Risk Score (FRS) is valid for perioperative complications.

SUMMARY OF BACKGROUND DATA

The FRS was previously formulated from a retrospective review of 364 fusion surgeries in patients over age 65. Patient demographics, comorbidities, surgical approach, levels, and osteotomies are incorporated in a weighted manner. This score correlated well with the risk of perioperative complications, operative time, estimated blood loss during surgery, and length of hospital stay.

MATERIALS AND METHODS

A new cohort of patients was studied. Subjects were 65 years old or older and had undergone routine elective thoracic or lumbar fusion surgery. The FRS was calculated for each subject to estimate risk (low, medium, or high) for perioperative complications. Actual incidences of major complications in the first 90 days after the surgery were noted and statistically compared with the predicted risk. The FRS was compared with intensive care unit admittance, estimated blood loss, operative time, and hospital length of stay to determine whether the score was predictive.

RESULTS

In total, 51% of our patients were at low risk (FRS, 1-3) for perioperative complications; 43% were at medium risk (FRS, 4-9); and 7% were at high risk (FRS, over 9). A total of 8% in the low-risk group, 23% in the medium-risk group, and 67% in the high-risk group actually developed significant perioperative complications. Medium-risk and high-risk patients experienced proportionally more perioperative complications than did low-risk patients; the difference was highly statistically significant.

CONCLUSIONS

This study validated the association between the FRS and complications in the first 90 days after thoracolumbar spinal fusion surgery on the basis of patient and surgery characteristics. It also predicts the risk of intensive care unit admission, operative time, blood loss, and hospital length of stay.

Eleven-Year Follow-Up of Two Cohorts of Patients Comparing Stand-Alone Porous Tantalum Cage Versus Autologous Bone Graft and Plating in Anterior Cervical Fusions

BACKGROUND

Anterior cervical discectomy and fusion with a porous tantalum cage is an accepted method to treat degenerated cervical discs, with good results, similar to those with autologous bone graft and plating at short- and mid-term follow-up. However, to date, long-term follow-up studies have been performed.

METHODS

We performed a retrospective, single-center study to evaluate the outcomes of 2 cohorts from a previous prospective randomized controlled trial comparing stand-alone tantalum cage (group 1, 27 patients) with autologous bone graft and plating (group 2, 30 patients) for single-level anterior cervical discectomy and fusion at 11 years of follow-up. The usual clinical and radiological outcomes and "overall success," proposed by the Food and Drug Administration, were evaluated.

RESULTS

The improvement in clinical outcomes achieved postoperatively was maintained similarly in the 2 cohorts at 11 years of follow-up. In group 1, the cage had subsided 2-3 mm in 12 patients (44%), segmental lordosis was maintained in 16 patients (59%), adjacent segment degeneration had developed or progressed in 27 of the adjacent segments (50%) in 15 patients (56%), and postoperative nonprogressive deformation of the anterior aspect of the cage was observed in 7 (26%) and minor fragmentation in 3 (11%) patients. In group 2, segmental lordosis was maintained in 90% of the patients and adjacent segment degeneration had developed or progressed in 15 patients (50%).

CONCLUSIONS

These results show that the clinical and radiological outcomes achieved at mid-term follow-up using a tantalum cage for single-level anterior cervical discectomy and fusion will be maintained for 11 years postoperatively, similar to the results with autologous bone graft and plating.

Clinical and radiographic outcomes of cervical disc arthroplasty with Prestige-LP Disc: a minimum 6-year follow-up study

Background

Cervical disc arthroplasty (CDA) has been considered as an alternative to cervical arthrodesis in the treatment of cervical degenerative disc diseases (CDDD). The aim of this study was to assess the long-term clinical and radiographic outcomes of CDA with Prestige-LP Disc.

Methods

A total of 61 patients who underwent single- or two-level CDA with Prestige-LP Disc were retrospectively investigated at a minimum of 6-year follow-up. Clinical assessments included visual analogue scale (VAS) for neck and arm pain, Neck Disability Index (NDI), and Japanese Orthopedic Association (JOA) score. Radiological evaluations included range of motion (ROM) of the index and adjacent levels, segmental angle, cervical sagittal alignment, heterotopic ossification (HO) and adjacent segment degeneration (ASD).

Results

Significant and maintained improvement in VAS for neck and arm, NDI and JOA were observed after a mean follow-up of 82.3 months (p < 0.001). The preoperative ROM of the index level was 9.7°, which was maintained at 2-and 4-year follow-up (9.3°, p = 0.597; 9.0°, p = 0.297), but was decreased to 8.0° at final follow-up (p = 0.019). Mobility was maintained in 80.5% (62/77) of the implanted prostheses at final follow-up. ROM of the superior and inferior adjacent segments, cervical sagittal alignment and cervical angel were all maintained. The incidence of HO was 42.9% at final follow-up, but it did not influence the clinical outcome. Radiographic ASD were detected in 29.5% of the patients. However, the incidence of symptomatic ASD was only 6.6%.

Conclusion

Cervical disc arthroplasty with Prestige-LP Disc demonstrated a maintained and satisfactory clinical outcome at a minimal of 6-year follow-up, with majority of the prostheses remained mobile. Cervical disc arthroplasty with Prestige-LP Dis can be considered as an effective surgical method in treating CDDD.

Are Controversial Issues in Cervical Total Disc Replacement Resolved or Unresolved?: A Review of Literature and Recent Updates

Since the launch of cervical total disc replacement (CTDR) in the early 2000s, many clinical studies have reported better outcomes of CTDR compared to those of anterior cervical discectomy and fusion. However, CTDR is still a new and innovative procedure with limited indications for clinical application in spinal surgery, particularly, for young patients presenting with soft disc herniation with radiculopathy and/or myelopathy. In addition, some controversial issues related to the assessment of clinical outcomes of CTDR remain unresolved. These issues, including surgical outcomes, adjacent segment degeneration (ASD), heterotopic ossification (HO), wear debris and tissue reaction, and multilevel total disc replacement (TDR) and hybrid surgeries are a common concern of spine surgeons and need to be resolved. Among them, the effect of CTDR on patient outcomes and ASD is theoretically and clinically important; however, this issue remains disputable. Additionally, HO, wear debris, multilevel TDR, and hybrid surgery tend to favor CTDR in terms of their effects on outcomes, but the potential of these factors for jeopardizing patients' safety postoperatively and/or to exert harmful effects on surgical outcomes in longer-term follow-up cannot be ignored. Consequently, it is too early to determine the therapeutic efficacy and cost-effectiveness of CTDR and will require considerable time and studies to provide appropriate answers regarding the same. For these reasons, CTDR requires longer-term follow-up data.

Evidence-Based Analysis of Adjacent Segment Degeneration and Disease After LIF: A Narrative Review

STUDY DESIGN

Narrative review.

OBJECTIVES

The etiology of adjacent segment degeneration (ASDeg) and adjacent segment disease (ASDz) after lumbar interbody fusion (LIF) remains controversial. The aim of this narrative review was to provide an evidence-based analysis of the peer-reviewed literature on clinical studies of ASDeg and ASDz after LIF.

METHODS

A review was performed utilizing Medline, Embase, and Cochrane databases. Two reviewers independently extracted relevant data from each included study. Statistical comparisons were made when appropriate.

RESULTS

Nine articles that matched the inclusion and exclusion criteria were included. All the studies were Level III and retrospective. MINORS scores ranged from 9.5 to 13. Clinical outcomes were assessed in all 9 studies, but only 6 studies used validated outcomes measures. Only 6 studies reported values for both ASDeg and ASDz. ASDeg alone was reported in 3 studies. Due to the variability in the criteria for designation as ASDz (different radiographic modalities) and ASDeg (different outcomes measures), we were unable to calculate frequency-weighted mean values or compare the various surgical techniques.

CONCLUSIONS

This review highlights the various limitations of the current literature on ASDeg and ASDz after lumbar fusion, specifically the absence of a rigorous definition and classification system and an extraordinary heterogeneity in methodology. There needs to be a fundamental shift in the current ASDeg and ASDz research landscape, toward a consensus, so that the high-level clinical research that is essential for treatment of spinal pathology may become available.

Progressive Bone Formation After Cervical Disc Replacement: Minimum of 5-Year Follow-up

STUDY DESIGN

Retrospective review.

OBJECTIVE

Our objective was to examine the prevalence, clinical significance, ramifications, and possible etiology of postoperative bone formation at the index level after cervical disc replacement (CDR) with a minimum of 5 years of follow-up.

SUMMARY OF BACKGROUND DATA

CDR can be complicated by postoperative ossification and unwanted ankylosis at the index level, which some authors have termed "heterotopic ossification." This terminology may be inaccurate as it assumes the postoperative bone formation is unnatural and a consequence of the CDR surgery. We advocate that this phenomenon has more to do with individual patient factors rather than the surgery.

METHODS

Patients who underwent Bryan CDR for cervical myelopathy or radiculopathy between 12/2003 and 8/2008 with a minimum of 5-years follow-up were analyzed. They were divided into two groups, those with and without postoperative bone formation. Patient-reported outcomes (Japanese Orthopaedic Association score, Neck Disability Index, Visual Analogue Scale for neck and arm pain) and radiographic parameters were collected pre- and postoperatively and compared between groups.

RESULTS

Sixty-one patients (76 levels) were identified (mean follow-up 94.2 mo). The overall incidence of postoperative ossification was 50%. Both groups had sustained significant improvements across all patient-reported outcome measures at final follow-up. Notably, patients with more severe preoperative cervical spondylosis had higher rates of postoperative ossification (P = 0.036) and adjacent segment degeneration (P = 0.010).

CONCLUSION

Although the long-term incidence of postoperative bone formation after CDR was relatively high, this did not adversely affect patient outcomes. Patients with more severe preoperative spondylosis had higher rates of postoperative ossification, suggesting that postoperative ossification at the CDR segment is likely one of progressive bone formation in individuals already predisposed to forming bone rather than one of alleged heterotopic ossification as a consequence of the surgery.

LEVEL OF EVIDENCE

3.

Whole Spine Disc Degeneration Survey according to the Ages and Sex Using Pfirrmann Disc Degeneration Grades

Objective

Pfirrmann disc grade is a useful scoring tool for evaluating disc degeneration, but normal values according to aging process has not been elucidated. This study was conducted to identify the prevalence and pattern of whole spine disc degeneration according to ages and gender differences.

Methods

Total 653 patients (336 male and 317 female patients, 48.1±58.7 years old) who took whole spine magnetic resonance images were enrolled in this study. There were 19 cases in their 2nd decades and 74 cases in 3rd decades, 141 cases in 4th decades, 129 cases in 5th decades, 139 cases in 6th decades, and 93 cases in 7th decades, 58 cases in over 8th decades. Pfirrmann disc grades were measured according to sex and ages by 2 neurosurgeons that were blind to this study.

Results

All spinal disc degeneration grades were correlated with ageing. The Pfirrmann disc grades of degeneration in all spine levels showed the statistically significant difference according to the ages (p<0.001). The common Pfirrmann disc grades according to the ages were grade 3 among 2nd to 5th decades, and grade 4 was more common than 6th decades. The lower cervical level (C2–3 to C4–5) and lumbar level (L1–2 to L5–S1) were happened relatively early severe disc degeneration compared to other levels. The intersexual differences were increased after 6th decades.

Conclusion

Disc degeneration is natural course after one’s 2nd decades. And its incidence and grade were increased with age, and more affected by sexual difference after 6th decades.

Quantification of Bone Marrow Edema by Magnetic Resonance Imaging Only Marginally Reflects Clinical Neck Pain Evaluation in Rheumatoid Arthritis and Ankylosing Spondylitis

OBJECTIVE

Neck pain is common in rheumatoid arthritis (RA) and ankylosing spondylitis (AS). We investigated the correlation of bone marrow edema (BME) on magnetic resonance imaging (MRI) in RA and AS and its association with clinical complaints of neck pain.

METHODS

Cervical spine short-tau inversion recovery-MRI and T1w-MRI of 34 patients with RA and 6 patients with AS complaining about neck pain were obtained. Clinical and laboratory data were available. BME was scored by 2 blinded readers using a modification of a published score, including various cervical sites. Degenerative changes were also quantified.

RESULTS

Patients were predominantly women (82.5%), and mean ± SD age was 57.5 ± 11.8 years, C-reactive protein (CRP) was 0.8 ± 1.3 mg/dl, and pain score was 46.0 ± 17.5. BME was detected in 24/40 patients (60%) involving the atlantoaxial region (21%), vertebral bodies (75%), facet joints (29%), and spinous processes (46%). Degenerative changes were identified in 21/40 patients (52.5%), 13 (62%) of whom also had BME in vertebral bodies. No differences were found between patients with versus without cervical BME for clinical assessments: numeric rating scale pain (median ± interquartile range) 5.5 ± 3.0 vs 6.0 ± 4.0 (p = 0.69), Funktionsfragebogen Hannover 68.2 ± 41.0 vs 42.0 ± 55.5 (p = 0.19), Northwick pain score 44.4 ± 21.8 vs 47.2 ± 27.0 (p = 0.83), or CRP 0.40 ± 0.80 vs 0.60 ± 0.66 (p = 0.94). For patients with degenerative changes, symptom duration was longer than for patients without (10 ± 12.5 vs 5.0 ± 18.0 yrs, p = 0.73).

CONCLUSION

In this small study of patients with RA and AS complaining about neck pain, BME was found in many different cervical sites, including the facet joints and the spinous processes. However, the occurrence and severity of BME did not correlate with the severity of neck pain.

Clinical Experiences of Non-fusion Dynamic Stabilization Surgery for Adjacent Segmental Pathology after Lumbar Fusion

BACKGROUND

As an alternative to spinal fusion, non-fusion dynamic stabilization surgery has been developed, showing good clinical outcomes. In the present study, we introduce our surgical series, which involves non-fusion dynamic stabilization surgery for adjacent segment pathology (ASP) after lumbar fusion surgery.

METHODS

Fifteen patients (13 female and 2 male, mean age of 62.1 years) who underwent dynamic stabilization surgery for symptomatic ASP were included and medical records, magnetic resonance images (MRI), and plain radiographs were retrospectively evaluated.

RESULTS

Twelve of the 15 patients had the fusion segment at L4-5, and the most common segment affected by ASP was L3-4. The time interval between prior fusion and later non-fusion surgery was mean 67.0 months. The Visual Analog Scale and Oswestry Disability Index showed values of 7.4 and 58.5% before the non-fusion surgery and these values respectively declined to 4.2 and 41.3% postoperatively at 36 months (p=0.027 and p=0.018, respectively). During the mean 44.8 months of follow-up, medication of analgesics was also significantly reduced. The MRI grade for disc and central stenosis identified significant degeneration at L3-4, and similar disc degeneration from lateral radiographs was determined at L3-4 between before the prior fusion surgery and the later non-fusion surgery. After the non-fusion surgery, the L3-4 segment and the proximal segment of L2-3 were preserved in the disc, stenosis and facet joint whereas L1-2 showed disc degeneration on the last MRI (p=0.032). Five instances of radiologic ASP were identified, showing characteristic disc-space narrowing at the proximal segments of L1-2 and L2-3. However, no patient underwent additional surgery for ASP after non-fusion dynamic stabilization surgery.

CONCLUSION

The proposed non-fusion dynamic stabilization system could be an effective surgical treatment for elderly patients with symptomatic ASP after lumbar fusion.

Nonfusion Does Not Prevent Adjacent Segment Disease: Dynesys Long-term Outcomes With Minimum Five-year Follow-up

STUDY DESIGN

Case series.

OBJECTIVE

The aim of this study was to determine the relationship between fusion and adjacent segment disease via Dynesys long-term outcomes.

SUMMARY OF BACKGROUND DATA

Dynesys is a dynamic stabilization system meant to improve symptoms by stabilizing the spine without fusion and avoiding the development of adjacent segment disease. However, few studies have evaluated long-term outcomes.

METHODS

All patients were operated on with Dynesys from 2006 to 2009 by a single surgeon at a single institution. We prospectively collected 18 variables among the following categories: patient characteristics, comorbidities, surgical indications, and OR variables. We analyzed two primary endpoints: solid fusion on X-ray and clinical adjacent segment disease (ASD) both at 5 years. Secondary endpoints were time to fusion, time to ASD, reoperation, Oswestry disability index (ODI), and visual analogue scale (VAS) leg pain. We conducted a multivariate analysis via the random forest method. Mann-Whitney U test and Fisher exact test were then used to qualify relationship between variables.

RESULTS

We had 52 patients to review in the database. Eight had preexisting ASD. Mean follow-up was 92 months (median 87 months). Fifteen had ASD (29%) during follow-up at a mean 45 months (Median 35 months). Nine had a solid fusion (17%), 2 of which also had ASD. Mean time to fusion was 65 months (median 71 months). Differences in improvement of ODI (P = 0.005) and VAS leg pain (P = 0.002) were significant favoring patients without ASD. The multivariate analysis revealed four variables associated with ASD: prior ASD (OR 11.3, P = 0.005), neurological deficit (OR 8.5, P = 0.018), revision OR (OR 8.5, P = 0.018), and multilevel degeneration (OR 0.184, P = 0.026). No variable was associated with fusion.

CONCLUSION

Dynesys was associated with a high rate of ASD over long-term follow-up despite maintaining a low fusion rate. Prior ASD was the strongest predictor of progressive ASD.

LEVEL OF EVIDENCE

3.

A Degenerative/Proinflammatory Intervertebral Disc Organ Culture: An Ex Vivo Model for Anti-inflammatory Drug and Cell Therapy

Resolution of intervertebral disc (IVD) degeneration-associated inflammation is a prerequisite for tissue regeneration and could possibly be achieved by strategies ranging from pharmacological to cell-based therapies. In this study, a proinflammatory disc organ culture model was established. Bovine caudal disc punches were needle punctured and additionally stimulated with lipopolysaccharide (10 μg/mL) or interleukin-1β (IL-1β, 10-100 ng/mL) for 48 h. Two intradiscal therapeutic approaches were tested: (i) a nonsteroidal anti-inflammatory drug, diclofenac (Df) and (ii) human mesenchymal stem/stromal cells (MSCs) embedded in an albumin/hyaluronan hydrogel. IL-1β-treated disc organ cultures showed a statistically significant upregulation of proinflammatory markers (IL-6, IL-8, prostaglandin E2 [PGE2]) and metalloproteases (MMP1, MMP3) expression, while extracellular matrix (ECM) proteins (collagen II, aggrecan) were significantly downregulated. The injection of the anti-inflammatory drug, Df, was able to reduce the levels of proinflammatory cytokines and MMPs and surprisingly increase ECM protein levels. These results point the intradiscal application of anti-inflammatory drugs as promising therapeutics for disc degeneration. In parallel, the immunomodulatory role of MSCs on this model was also evaluated. Although a slight downregulation of IL-6 and IL-8 expression could be found, the variability among the five donors tested was high, suggesting that the beneficial effect of these cells on disc degeneration needs to be further evaluated. The proinflammatory/degenerative IVD organ culture model established can be considered a suitable approach for testing novel therapeutic drugs, thus reducing the number of animals in in vivo experimentation. Moreover, this model can be used to address the cellular and molecular mechanisms that regulate inflammation in the IVD and their implications in tissue degeneration.

Hybrid Surgery Combined with Dynamic Stabilization System and Fusion for the Multilevel Degenerative Disease of the Lumbosacral Spine

BACKGROUND

As motion-preserving technique has been developed, the concept of hybrid surgery involves simultaneous application of two different kinds of devices, dynamic stabilization system and fusion technique. In the present study, the application of hybrid surgery for lumbosacral degenerative disease involving two-segments and its long-term outcome were investigated.

METHODS

Fifteen patients with hybrid surgery (Hybrid group) and 10 patients with two-segment fusion (Fusion group) were retrospectively compared.

RESULTS

Preoperative grade for disc degeneration was not different between the two groups, and the most common operated segment had the most degenerated disc grade in both groups; L4-5 and L5-S1 in the Hybrid group, and L3-4 and L4-5 in Fusion group. Over 48 months of follow-up, lumbar lordosis and range of motion (ROM) at the T12-S1 global segment were preserved in the Hybrid group, and the segmental ROM at the dynamic stabilized segment maintained at final follow-up. The Fusion group had a significantly decreased global ROM and a decreased segmental ROM with larger angles compared to the Hybrid group. Defining a 2-mm decrease in posterior disc height (PDH) as radiologic adjacent segment pathology (ASP), these changes were observed in 6 and 7 patients in the Hybrid and Fusion group, respectively. However, the last PDH at the above adjacent segment had statistically higher value in Hybrid group. Pain score for back and legs was much reduced in both groups. Functional outcome measured by Oswestry disability index (ODI), however, had better improvement in Hybrid group.

CONCLUSION

Hybrid surgery, combined dynamic stabilization system and fusion, can be effective surgical treatment for multilevel degenerative lumbosacral spinal disease, maintaining lumbar motion and delaying disc degeneration.

Age and pro-inflammatory gene polymorphisms influence adjacent segment disc degeneration more than fusion does in patients treated for chronic low back pain

PURPOSE

Does lumbar fusion lead to accelerated adjacent segment disc degeneration (ASDD) or is it explained by genetics and aging? The influence of genetics on ASDD remains to be explored. This study assesses whether the disc space height adjacent to a fused segment is associated with candidate gene single nucleotide polymorphisms (SNPs).

METHODS

Patients with low back pain from four RCTs (N = 208 fusion; 77 non-operative treatment) underwent standing plain radiography and genetic analyses at 13 ± 4 years follow-up. Disc space height was measured using a validated computer-assisted distortion-compensated roentgen analysis technique and reported in standard deviations from normal values. Genetic association analyses included 34 SNPs in 25 structural, inflammatory, matrix degrading, apoptotic, vitamin D receptor and OA-related genes relevant to disc degeneration. These were analysed for their association with disc space height (after adjusting for age, gender, smoking, duration of follow-up and treatment group) first, separately, and then together in a stepwise multivariable model.

RESULTS

Two SNPs from the IL18RAP gene (rs1420106 and rs917997) were each associated with a lower disc space height at the adjacent level (B = -0.34, p = 0.04 and B = -0.35, p = 0.04, respectively) and the MMP-9 gene SNP rs20544 was associated with a greater disc space height (B = 0.35, p = 0.04). Age (p < 0.001) and fusion (p < 0.008) were also significant variables in each analysis. The total explained variance in disc space height was for each SNP model 13-14 %, with 11-12 % of this being accounted for by the given SNP, 64-67 % by age and 19-22 % by fusion. In the multivariable regression analysis (with nine SNPs selected for entry, along with the covariates) the total explained variance in disc space height was 23 %, with the nine SNPs, age and fusion accounting for 45, 45 and 7 % of this, respectively.

CONCLUSIONS

Age was the most significant determinant of adjacent segment disc space height followed by genetic factors, specifically inflammatory genes. Fusion explained a statistically significant but small proportion of the total variance. Much of the variance remained to be explained.

Iatrogenic contributions to cervical adjacent segment pathology: review article

BACKGROUND

Anterior cervical discectomy and fusion (ACDF) is widely accepted as a predictably excellent procedure. On the other hand, adjacent level pathology following ACDF is a well-known phenomenon which undercuts surgical outcome. However, the extent to which ACDF accelerates this phenomenon in the naturally degenerating cervical spine is still to be understood.

QUESTIONS/PURPOSES

To summarize the current evidence concerning adjacent segment pathology in the light of biomechanics, natural history, postoperative course, and comparison between ACDF and total disc replacement (TDR).

METHODS

This is a study of published articles. Articles were searched by the topic of adjacent disc pathology in cervical spine through Google Scholar and Pubmed. After review, 37 published articles were deemed suitable for the subject of this study.

RESULTS

Biomechanical and clinical data strongly suggest that ASP is a presentation of the iatrogenically accelerated natural aging process of cervical spine. However, power study analysis with assumption showed that current RCTs are unlikely to prove this suggestion.

CONCLUSION

Available data suggests that iatrogenic factors play a significant role in adjacent segment pathology following ACDF.

[Posterior lumbar interbody fusion implants. Software assisted planning--preliminary results]

BACKGROUND

Sagittal imbalance, adjacent segment degeneration, and loss of correction due to cage sintering are the main reasons for revision surgery after lumbar fusion. Based on the experience from hip and knee replacement surgery, preoperative software-assisted planning combined with the corresponding cages is helpful to achieve better long-term results.

OBJECTIVES

Evaluation of the procedure regarding intraoperative application of preoperative planning and examination to what extent the planning was correct.

MATERIALS AND METHODS

In all, 30 patients were included in the period from September 2012 to May 2013 in an observational study, planned preoperatively with the planning software, and treated with the corresponding PLIF cages. The radiological evaluation was performed by thin-layer CT after 3 months.

RESULTS

A total of 24 (80%) patients were followed up after 3 months. In these 24 patients, the preoperative planning actually was correct in 17 cases with the intraoperatively implanted cage, which corresponds to a match of about 71%. The fusion rate for these 24 patients who underwent full examinations was 91.7%.

CONCLUSION

The results of this observational study to evaluate the planning of intervertebral cages show positive experience with this novel therapeutic concept. Despite the limited number of participants, good results were observed for the intraoperative implementation of the planned cages and an adequate fusion rate was obtained. Irrespective of this, a software-based surgical planning must be questioned critically any time. Ultimately, it is the surgeon's responsibility to modify the planned procedure intraoperatively if necessary. Currently, the influence of this planning regarding the long-term course and the important question of adjacent segment instability remains unanswered.

Low-back pain

Low-back pain is one of the most common painful conditions experienced by humans throughout their life. Some occupational risk factors (namely, heavy manual material handling) may also contribute to the development of low-back pain: due to the high prevalence of both low-back pain and manual material handling in the adult working population, it has been estimated that low-back pain is probably the most common occupational disorder worldwide. Lifetime prevalence of low-back pain has been reported to be as high as 84%, depending on the case definition used, and no age group is spared, even children. Although low-back pain is not a lethal condition, it was estimated at the third rank among all diseases by disability-adjusted life-years in 2010 in the USA, after ischemic heart disease and chronic obstructive pulmonary disease, and at the first rank by years lived with disability. It also ranked high (13th) globally for the same year, in disability-adjusted life-years. Low-back pain is currently classified as nonspecific/specific as to putative cause and as acute (lasting less than 6 weeks), subacute (6-12 weeks), or chronic (more than 12 weeks) according to duration of symptoms. The distinction between nonspecific/specific and acute/subacute/chronic low-back pain is useful not only for epidemiologic studies, but also (mainly) for choosing the appropriate strategy for the diagnosis and treatment of the disorder. Workplace risk factors for low-back pain include manual lifting and whole-body vibration exposure. This chapter will provide an overview of modern concepts of low-back pain (in general) and will then outline some distinctive features of work-related low-back pain.

ISSLS Prize winner: Long-term follow-up suggests spinal fusion is associated with increased adjacent segment disc degeneration but without influence on clinical outcome: results of a combined follow-up from 4 randomized controlled trials

STUDY DESIGN

Cross-sectional analysis of long-term follow-up (LTFU) data from 4 randomized controlled trials of operative versus nonoperative treatment for chronic low back pain.

OBJECTIVE

To examine the influence of spinal fusion on adjacent segment disc space height as an indicator of disc degeneration at LTFU.

SUMMARY OF BACKGROUND DATA

There is ongoing debate as to whether adjacent segment disc degeneration results from the increased mechanical stress of fusion.

METHODS

Plain standing lateral radiographs were obtained at LTFU (mean, 13 ± 4 yr postrandomization) in 229 of 464 (49%) patients randomized to surgery and 140 of 303 (46%), to nonoperative care. Disc space height and posteroanterior displacement were measured for each lumbar segment using a validated computer-assisted distortion compensated roentgen analysis technique. Values were reported in units of standard deviations above or below age and sex-adjusted normal values. Patient-rated outcomes included the Oswestry Disability Index and pain scales.

RESULTS

Radiographs were usable in 355 of 369 (96%) patients (259 fusion and 96 nonoperative treatment). Both treatment groups showed significantly lower values for disc space height of the adjacent segment than norm values. There was a significant difference between treatment groups for the disc space height of the cranial adjacent segment (in both as-treated and intention-to-treat analyses). The mean treatment effect of fusion on adjacent segment disc space height was -0.44 SDs (95% CI, -0.77 to -0.11; P = 0.01; as-treated analysis); there was no group difference for posteroanterior displacement (0.18 SDs, 95% confidence interval, -0.28 to 0.64, P = 0.45). Adjacent level disc space height and posteroanterior displacement were not correlated with Oswestry Disability Index or pain scores at LTFU (r = 0.010-0.05; P > 0.33).

CONCLUSION

Fusion was associated with lower disc space height at the adjacent segment after an average of 13 years of FU. The reduced disc space height had no influence on patient self-rated outcomes (pain or disability).

LEVEL OF EVIDENCE

2.

Use of thoracic spine thrust manipulation for neck pain and headache in a patient following multiple-level anterior cervical discectomy and fusion: a case report

STUDY DESIGN

Case report.

BACKGROUND

Thoracic spine thrust manipulation has been shown to be an effective intervention for individuals experiencing mechanical neck pain.

CASE DESCRIPTION

The patient was a 46-year-old woman referred to outpatient physical therapy 2 months following multiple-level anterior cervical discectomy and fusion. At initial evaluation, primary symptoms consisted of frequent headaches, neck pain, intermittent referred right elbow pain, and muscle fatigue localized to the right cervical and upper thoracic spine regions. Initial examination findings included decreased passive joint mobility of the thoracic spine, limited cervical range of motion, and limited right shoulder strength. Outcome measures consisted of the numeric pain rating scale, the Neck Disability Index, and the global rating of change scale. Treatment consisted of a combination of manual therapy techniques aimed at the thoracic spine, therapeutic exercises for the upper quarter, and patient education, including a home exercise program, over a 6-week episode of care.

OUTCOMES

Immediate reductions in cervical-region pain (mean ± SD, 2.0 ± 1.1) and headache (2.0 ± 1.3) intensity were reported every treatment session immediately following thoracic spine thrust manipulation. At discharge, the patient reported 0/10 cervical pain and headache symptoms during all work-related activities. From initial assessment to discharge, Neck Disability Index scores improved from 46% to 16%, with an associated global rating of change scale score of +7 ("a very great deal better").

DISCUSSION

This case report describes the immediate and short-term clinical outcomes for a patient presenting with symptoms of neck pain and headache following anterior cervical discectomy and fusion surgical intervention. Clinical rationale and patient preference aided the decision to incorporate thoracic spine thrust manipulation as a treatment for this patient. Level of Evidence Therapy, level 4.

The Incidence of Adjacent Segment Breakdown in Polysegmental Thoracolumbar Fusions of Three or More Levels with Minimum 5-Year Follow-up

Study Design Retrospective cohort study. Objective To identify the incidence of adjacent segment pathology (ASP) after thoracolumbar fusion of three or more levels, the risk factors for the development of ASP, and the need for further surgical intervention in this particular patient population. Methods A retrospective analysis of a prospective surgical database identified 217 patients receiving polysegmental (≥ 3 levels) spinal fusion with minimum 5-year follow-up. Risk factors were evaluated, and the following data were obtained from the review of radiographs and charts: radiographic measures-levels fused, fusion status, presence of ASP; clinical measures-patient assessment, Oswestry Disability Index (ODI), and the need for further surgery. Results The incidence of radiographic ASP (RASP) was 29%; clinical or symptomatic ASP (CASP), 18%; and those requiring surgery, 9%. Correlation was observed between ODI and ASP, symptomatic ASP, and need for revision surgery. Age, preoperative degenerative diagnosis, and absence of fusion demonstrated significant association to ASP. Conclusions ASP was observed in a significant number of patients receiving polysegmental fusion of three or more levels. ODI scores correlated to RASP, CASP, and the need for revision surgery.

Postoperative spine complications

Imaging of the postoperative spine is common, although it remains a difficult task for radiologists. This article presents an overview of common surgical approaches and spinal hardware, and specific complications that may be associated with each procedure. In addition, expected postoperative changes and complications that are common among procedures, with their differential diagnosis and imaging features, are discussed.