Laminoplasty and pedicle screw fixation for cervical myelopathy associated with athetoid cerebral palsy: minimum 5-year follow-up

Reoperation Rates According to Surgical Approach After Operation for Degenerative Cervical Pathology in Patients With Athetoid Cerebral Palsy: A Nationwide Cohort Study

STUDY DESIGN

National population-based cohort study.

OBJECTIVE

The overall complication rate for patients with athetoid cerebral palsy (CP) undergoing cervical surgery is significantly higher than that of patients without CP. The study was conducted to compare the reoperation and complication rates of anterior fusion, posterior fusion, combined fusion, and laminoplasty for degenerative cervical myelopathy/radiculopathy in patients with athetoid cerebral palsy.

METHODS

The Korean Health Insurance Review and Assessment Service national database was used for analysis. Data from patients diagnosed with athetoid CP who underwent cervical spine operations for degenerative causes between 2002 and 2020 were reviewed. Patients were categorized into four groups for comparison: anterior fusion, posterior fusion, combined fusion, and laminoplasty.

RESULTS

A total of 672 patients were included in the study. The overall revision rate was 21.0% (141/672). The revision rate was highest in the anterior fusion group (42.7%). The revision rates of combined fusion (11.1%; hazard ratio [HR], .335; P = .002), posterior fusion (13.8%; HR, .533; P = .030) were significantly lower than that of anterior fusion. Revision rate of laminoplasty (13.1%; HR, .541; P = .240) was also lower than anterior fusion although the result did not demonstrate statistical significance.

CONCLUSION

Anterior fusion presented the highest reoperation risk after cervical spine surgery reaching 42.7% in patients with athetoid CP. Therefore, anterior-only fusion in patients with athetoid CP should be avoided or reserved for strictly selected patients. Combined fusion, with the lowest revision risk at 11.1%, could be safely applied to patients with athetoid CP.

Combined Anterior-Posterior Fusion Versus Posterior Alone Fusion for Cervical Myelopathy in Athetoid-Cerebral Palsy

STUDY DESIGN

Retrospective comparative study.

OBJECTIVES

Although some studies have discussed the use of lateral mass screws (LMSs) in patients with cerebral palsy (CP), it is unclear whether posterior LMS fixation alone is a suitable method. We aimed to compare the clinical, radiological, and surgical outcomes of 2 surgical modalities, namely, combined anterior-posterior (A-P) instrumented fusion and posterior fusion alone, in athetoid-type CP patients with cervical myelopathy (CM).

METHODS

We analyzed 63 patients with athetoid-CP and CM who underwent posterior fusion only with LMS (group A, 35 patients) and A-P fusion (group B, 28 patients). The primary outcome was the 1- and 3-year fusion rates for the surgical segments. The secondary outcomes included the clinical outcomes based on pain intensity determined using the visual analog scale score, neck disability index, and 17-point Japanese Orthopedic Association score, radiological, and surgical outcomes.

RESULTS

Fusion was achieved at 3 years postoperatively in 22 of 35 patients (63%) in group A and in 26 of 28 patients (93%) in group B (P = 0.02). The posterior neck pain intensity was also significantly lower in group B than in group A 2 and 3 years postoperatively (P = 0.02 and 0.01, respectively). The incidence of screw loosening and implant-related problems was higher in group A (60%) than in group B (21%) (P = 0.01). The other clinical and radiological parameters were similar between the groups.

CONCLUSIONS

For athetoid CP-induced CM, combined A-P fusion would result in superior clinical and radiological outcomes compared to posterior fusion alone.

Crossing the Cervicothoracic Junction in Multilevel Cervical Arthrodesis: A Systematic Review & Meta-Analysis

INTRODUCTION

In multisegment cervical arthrodeses, a common clinical dilemma for the surgeon is whether to extend the fusion past the cervicothoracic junction (CTJ).

OBJECTIVE

This meta-analysis compares clinical outcomes and radiological parameters when crossing and not crossing the CTJ.

METHODS

Our outcomes of interest included overall reoperation, successful fusion, adjacent segment disease (ASD) leading to revision surgery, estimated blood loss (EBL), length of stay (LOS). We also studied the postoperative change in radiological parameters - cervical sagittal vertical axis (cSVA), cervical lordosis (CL), and T1 slope (T1S) - and change in Neck Disability Index (NDI) and neck pain in Visual Analog Scale (VAS).

RESULTS

Thirteen studies with 1,720 patients were included. There were 974 (56.6%) patients in the non-crossing group and 746 (43.4%) patients in the crossing group. Non-crossing was associated with a higher risk of overall reoperation (RR=1.56; 95% CI:0.98-2.47) and ASD requiring revision surgery (RR=2.82; 95% CI:1.33-5.98; number-needed-to-harm = 22). The non-crossing group had lower EBL by 175 mL and shorter LOS by one day; the latter finding was only trending towards statistical significance. Successful fusion, as well as changes in cSVA, CL, NDI, and VAS were not different between the two groups at a statistically significant level.

CONCLUSIONS

In multilevel cervical arthrodesis, not crossing the CTJ is associated with a higher risk of overall reoperation and ASD requiring reoperation than crossing the CTJ, along with lower EBL and LOS. Differences in successful fusion, patient-reported outcomes, and sagittal radiological parameters were not significant.

No Difference in Reoperation Rates for Adjacent Segment Disease (Operative Adjacent Segment Disease) in Posterior Cervical Fusions Stopping at C7 Versus T1/T2: A Cohort of 875 Patients-Part 1

STUDY DESIGN

A retrospective cohort study with chart review.

OBJECTIVE

To determine whether there is a difference in reoperation rates for adjacent segment disease ([ASD] operative ASD) in posterior cervical fusions (PCFs) that stop at -C7 versus -T1/T2.

SUMMARY OF BACKGROUND DATA

There are surgical treatment challenges to the anatomical complexities of the cervicothoracic junction. Current posterior cervical spine surgery is based on the belief that ASD occurs if fusions are stopped at C7 although there is varying evidence to support this assumption.

METHODS

Patients were followed until validated reoperations for ASD, membership termination, death, or March 31, 2020. Descriptive statistics and 5-year crude incidence rates and 95% confidence intervals for operative ASD for PCF ending at -C7 or -T1/T2 were reported. Time-dependent crude and adjusted multivariable Cox-Proportional Hazards models were used to evaluate operative ASD rates with adjustment for covariates or risk change estimates more than 10%.

RESULTS

We identified 875 patients with PCFs (beginning at C3 or C4 or C5 or C6) stopping at either -C7 (n = 470) or -T1/T2 (n = 405) with average follow-up time of 4.6 (±3.3) years and average time to operative ASD of 2.7 (±2.8) years. Crude overall incidence rates for stopping at -C7 (2.12% [1.02%-3.86%]) and -T1/T2 (2.48% [1.25%-4.40%]) were comparable with no statistical difference in risk (adjusted hazard ratio = 1.47, 95% confidence interval = 0.61-3.53, P = 0.39). In addition, we observed no differences in the probability of operative ASD in competing risk time-dependent models (Grey test P  = 0.448).

CONCLUSION

A large cohort of 875 patients with PCFs stopping at -C7 or -T1/T2 with an average follow-up of more than 4 years found no statistical difference in reoperation rates for ASD (operative ASD).Level of Evidence: 3.

Factors Affecting Postoperative Complications and Outcomes of Cervical Spondylotic Myelopathy with Cerebral Palsy : A Retrospective Analysis

Objective

Cervical surgery in patients with cervical spondylotic myelopathy (CSM) and cerebral palsy (CP) is challenging owing to the complexities of the deformity. We assessed factors affecting postoperative complications and outcomes after CSM surgery in patients with CP.

Methods

Thirty-five consecutive patients with CP and CSM who underwent cervical operations between January 2006 and January 2014 were matched to 35 non-cerebral palsy (NCP) control patients. Postoperative complications and radiologic outcomes were compared between the groups. In the CP group, the Japanese Orthopaedic Association score; Oswestry neck disability index; modified Barthel index; and values for the grip and pinch, Box and Block, and Jebsen-Taylor hand function tests were obtained preand postoperatively and compared between those with and without postoperative complications.

Results

Sixteen patients (16/35%) in the CP group and seven (7/35%) in the NCP group (p=0.021) had postoperative complications. Adjacent segment degeneration (p=0.021), postoperative motor weakness (p=0.037), and revisions (p=0.003) were significantly more frequent in the CP group than in the NCP group; however, instrument-related complications were not significantly higher in the CP group (7/35 vs. 5/35, p=0.280). The number of preoperative fixed cervical deformities were significantly higher in CP with postoperative complications (5/16 vs. 1/19, p=0.037). In the CP group, clinical outcomes were almost similar between those with and without postoperative complications.

Conclusion

The occurrence of complications during the follow-up period was high in patients with CP. However, postoperative complications did not significantly affect clinical outcomes.

Complex Revision Surgery for Cervical Deformity or Implant Failure

Postoperative cervical deformity sometimes occurs in the short or long term after primary surgery for cervical disorders related to the degenerative aging spine, neoplastic etiologies, hemodialysis, infection, inflammation, trauma, etc. Cervical kyphosis after posterior decompression surgery, such as laminectomy or laminoplasty, is a common problem for spine surgeons. However, revision surgery for cervical deformity is definitely one of the most challenging areas for spine surgeons. There is no doubt that surgery for cervical deformity carries a high risk of surgery-related complications that might result in aggravation of health-related quality of life. Revision surgery is even more challenging. Hence, spine surgeons need to assess carefully the overall severity of the underlying condition before revision surgery, and try to refine the surgical strategy to secure safe surgery. Needless to say, spine surgeons are now facing great challenges in making spine surgery a much more reliable and convincing entity.

More Than 10-year Follow-up After Laminoplasty and Pedicle Screw Fixation for Cervical Myelopathy Associated With Athetoid Cerebral Palsy

STUDY DESIGN

Retrospective case series.

OBJECTIVE

The aim of this study was to investigate the clinical outcomes >10 years following laminoplasty and pedicle screw fixation for cervical myelopathy associated with athetoid cerebral palsy (CP).

SUMMARY OF BACKGROUND DATA

Surgery for cervical myelopathy associated with CP remains a challenge because of perioperative instrumentation failure and adjacent segment problems due to patients' repetitive involuntary neck movements with deformity of the cervical spine.

METHODS

A single-center series of 14 patients were reviewed. The patients comprised seven women and seven men with a mean age of 52 years at the time of surgery. The mean follow-up period was 12.5 years. The Barthel index (BI), which shows independence in activities of daily life, and Japanese Orthopaedic Association (JOA) score were assessed. Radiographic evaluation included changes of the C2-C7 angle in the sagittal plane, fusion rate, adjacent segment degeneration, and instrument failure.

RESULTS

The 10-year BI and JOA score significantly improved at 36% and 31%, respectively. The preoperative Cobb angle of the sagittal plane from C2-C7 measured 11.9° of kyphosis, which improved to 0.8° of lordosis. In the radiographic analysis, 35% (proximal) and 21% (distal) of the adjacent segment showed progression in degeneration of more than one grade after 10 years. More than 90% of the patients who underwent magnetic resonance imaging showed progressive disc degeneration on either side after 10 years. Autofusion inside the disc or anterior vertebral bony bridging was observed in 86% of intervertebral levels without anterior procedures.

CONCLUSION

The procedure showed favorable initial stability and maintained favorable clinical outcomes in patients with CP. More than 90% of the patients showed disc degeneration on either side. The rate of proximal adjacent segment degeneration was higher than that of distal segments with or without symptoms at the >10-year follow-up.

LEVEL OF EVIDENCE

4.

Combined Laminoplasty and Posterior Fusion for Cervical Spondylotic Myelopathy Treatment: A Literature Review

Study Design

A literature review.

Purpose

To explore the utility of laminoplasty in combination with instrumented fusion, with a focus on neurological outcomes and changes in kyphotic deformity.

Overview of Literature

Management of cervical spondylotic myelopathy (CSM) to reduce morbidity within the neurosurgical population.

Methods

A US National Library of Medicine PubMed search was conducted for manuscripts pertaining to cervical laminoplasty and fusion for the management of CSM. Several relevant studies were shortlisted for review, and the bibliographies of the articles were searched for additional references. The search was limited to human studies, English-language literature, and reports on more than one patient.

Results

Combined laminoplasty and fusion was found to provide at least comparable, if not superior, neurological outcomes in specific patient populations with CSM. The Japanese Orthopedic Association scores, local kyphosis, and C2–C7 angle have been reviewed in several manuscripts, and improvement in each of these categories was found with laminoplasty and fusion.

Conclusions

The treatment of CSM necessitates an individualized approach based on the pathoanatomical variation. Laminoplasty and fusion can be appropriately used for patients with CSM in a setting of local kyphotic deformity, ossification of the posterior longitudinal ligament, associated segmental instability, and the need for strong stabilization.

A Novel Technique for Cervical Laminoplasty Fusion: Simultaneously Enhancing Stabilization and Decompression in Various Cervical Myelopathies: A Technical Note and Outcomes

BACKGROUND

Cervical laminectomy has 2 major disadvantages: postlaminectomy adhesion of dural membrane and lack of a fusion bed. The objective of this study was to determine whether simultaneous cervical laminoplasty with fusion (CLPF) might overcome these unwanted outcomes.

METHODS

Patients who underwent CLPF for treating cervical myelopathy with instability who were followed up for at least 12 months were enrolled. Preoperative and postoperative Neck Disability Index (NDI) and Japanese Orthopedic Association (JOA) scores before and after surgery, recovery rates (RRs), C2-C7 lordosis, and fusion success rates were evaluated.

RESULTS

The study cohort comprised 50 patients (35 males and 15 females; mean age, 60.5 ± 14.0 years) who underwent CLPF. The average duration of clinical follow-up was 24.6 ± 16.1 months. Mean preoperative and postoperative NDI scores were 27.0 ± 10.6 and 17.6 ± 7.2, respectively (P = 0.004). Mean preoperative and postoperative JOA scores were 10.4 ± 4.2 and 13.6 ± 3.0, respectively (P = 0.001). The mean JOA RR was 49.8 ± 42.2%. No significant changes in C2-7 lordosis were noted after surgery (preoperative, 7.0 ± 8.0°; postoperative, 7.3 ± 6.3°; P = 0.789). The fusion success rate was 96% (48 of 50 patients). Fusion mass areas at C5 level were significantly different between the opening side and the hinge side (opening side, 15.8 ± 13.1 mm²; hinge side, 50.8 ± 27.2 mm²; P < 0.001). There was no postoperative restenosis or epidural fibrosis.

CONCLUSIONS

CLPF might be useful for canal decompression and a good fusion bed while avoiding postoperative epidural fibrosis.

Surgical Outcomes of Posterior Spinal Fusion Alone Using Cervical Pedicle Screw Constructs for Cervical Disorders Associated With Athetoid Cerebral Palsy

STUDY DESIGN

Retrospective case series.

OBJECTIVE

The aim of this study was to investigate clinical outcomes after posterior spinal fusion (PSF) using cervical pedicle screw (CPS) constructs for cervical disorders associated with athetoid cerebral palsy (CP).

SUMMARY OF BACKGROUND DATA

Traditionally, most patients with cervical myelopathy associated with CP have required combined anterior and posterior fusion to achieve solid stability against severe involuntary movement.

METHODS

Thirty-one CP patients with cervical disorders who underwent PSF alone with a minimum 2-year follow-up (mean 58 months) were analyzed. All patients were treated with PSF using CPS constructs with or without decompression procedures. The average number of fused segments was 5.1 (range, 1-10 segments), and a halo jacket was applied in 16 patients for at least 2 months after surgery. Clinical outcomes using the Japanese Orthoedic Association scoring system (JOA score) and walking ability, radiographic sagittal alignment, fusion status, and surgery-related complications were evaluated.

RESULTS

The JOA score improved from 8.3 points preoperatively to 10.9 points at the final follow-up (P < 0.05). Although no patients experienced deterioration in their walking ability postoperatively, 10 patients were unable to walk at the final follow-up. Sagittal alignment, including C0-2 angle, C2-7 angle, and local alignment in fused segments, was maintained postoperatively. Twenty-five patients achieved fusion at the final follow-up (fusion rate: 81%), and fivepatients with nonunion required additional surgery. With regard to complications, 5 patients encountered postoperative upper extremity palsy.

CONCLUSION

The CPS construct is amenable to achieve a relatively high fusion rate without correction loss, and good clinical outcomes can be achieved with a posterior single approach for CP patients. In the future, efforts should be made to make appropriate decisions regarding the fusion area, take preventative measures against postoperative upper extremity palsy, and simplify external orthoses after surgery, especially with the use of a halo jacket.

LEVEL OF EVIDENCE

4.

Surgical Outcomes of Cervical Myelopathy in Patients with Athetoid Cerebral Palsy: A 5-Year Follow-Up

Study Design

Observational cohort study.

Purpose

To assess the surgical outcomes of posterior decompression and fusion for cervical myelopathy in patients with athetoid cerebral palsy.

Overview of Literature

Patients with athetoid cerebral palsy demonstrate involuntary movements and develop severe cervical spondylosis with kyphosis. In these patients, surgery is often performed at an early age because of myelopathy. A few studies have reported about the long-term outcomes of surgical treatment; however, they contain insufficient information.

Methods

From 2003 to 2008, 13 patients with cervical myelopathy due to athetoid cerebral palsy underwent posterior fusion surgery and were included in this study. The Japanese Orthopaedic Association (JOA) score, neck disability index (NDI), C2–7 angle on radiography, and need for additional surgical treatment were examined at 1 and 5 years postoperatively.

Results

The mean C2–7 angle was −10.5°±21.1° preoperatively and was corrected to −2.9°±13.5° immediately postoperatively. This improvement was maintained for 5 years. The JOA score was 9.5±2.5 preoperatively and 12.2±1.7 at the 5-year follow-up. NDI was 17±6.9 preoperatively and 16±7.5 at the 5-year follow-up. Patient satisfaction with surgery on a 100-point scale was 62.2±22.5 at the 5-year follow-up. Three patients needed additional surgery for loosening of screws. These results demonstrate good surgical outcomes for posterior fusion at 5 years.

Conclusions

Posterior decompression and fusion should be considered a viable option for cervical myelopathy in patients with athetoid cerebral palsy.

Outcomes of cervical laminoplasty-Population-level analysis of a national longitudinal database

OBJECTIVE

Cervical laminoplasty is an important alternative to laminectomy in decompressing of the cervical spine. Further evidence to assess the utility of laminoplasty is required. We examine outcomes of cervical laminoplasty via a population level analysis in the United States.

METHODS

We performed a population-level analysis using the national MarketScan longitudinal database to analyze outcomes and costs of cervical laminoplasty between 2007 and 2014. Outcomes included postoperative complications, revision rates, and functional outcomes.

RESULTS

Using a national administrative database, we identified 2613 patients (65.6% male, mean 58.5 years) who underwent cervical laminoplasty. Mean length of stay was 3.1 ± 2.8 days and mean follow-up was 795.5 ± 670.6 days. The overall complication rate was 22.5% (N = 587), 30-day readmission rate was 7.5% (N = 195), and mortality rate was 0.08% (N = 2, elderly patients only). The complication rate was significantly increased in elderly patients (age >65 years) compared to non-elderly patients (OR 0.751, p < .01). The use of intraoperative neuromonitoring (IONM) during the cervical laminoplasty procedure did not significantly impact outcomes. The overall re-operation rate after the initial procedure was 10.9%. Total costs of cervical laminoplasty were mainly driven by hospital charges with physician-related payments comprising a small amount.

CONCLUSIONS

Our national analysis of cervical laminoplasty found the procedure to be clinically effective with low complication rates and postoperative symptomatic improvement.

Laminoplasty with lateral mass screw fixation for cervical spondylotic myelopathy in patients with athetoid cerebral palsy: A retrospective study

Although several studies report various treatment solutions for cervical spondylotic myelopathy in patients with athetoid cerebral palsy, long-term follow-up studies are very rare. None of the reported treatment solutions represent a gold standard for this disease owing to the small number of cases and lack of long-term follow-up. This study aimed to evaluate the outcomes of laminoplasty with lateral mass screw fixation to treat cervical spondylotic myelopathy in patients with athetoid cerebral palsy from a single center.This retrospective study included 15 patients (9 male patients and 6 female patients) with athetoid cerebral palsy who underwent laminoplasty with lateral mass screw fixation for cervical spondylotic myelopathy at our hospital between March 2006 and June 2010. Demographic variables, radiographic parameters, and pre- and postoperative clinical outcomes determined by the modified Japanese Orthopedic Association (JOA), Neck Disability Index (NDI), and visual analog scale (VAS) scores were assessed.The mean follow-up time was 80.5 months. Developmental cervical spinal canal stenosis (P = 0.02) and cervical lordosis (P = 0.04) were significantly correlated with lower preoperative modified JOA scores. The mean modified JOA scores increased from 7.97 preoperatively to 12.1 postoperatively (P < 0.01). The mean VAS score decreased from 5.30 to 3.13 (P < 0.01), and the mean NDI score decreased from 31.73 to 19.93 (P < 0.01). There was a significant negative correlation between developmental cervical spinal canal stenosis and recovery rate of the modified JOA score (P = 0.01).Developmental cervical spinal canal stenosis is significantly related to neurological function in patients with athetoid cerebral palsy. Laminoplasty with lateral mass screw fixation is an effective treatment for cervical spondylotic myelopathy in patients with athetoid cerebral palsy and developmental cervical spinal canal stenosis.

Surgical outcomes of cervical spondylotic myelopathy: an analysis of a national, administrative, longitudinal database

OBJECTIVE

The authors performed a population-based analysis of national trends, costs, and outcomes associated with cervical spondylotic myelopathy (CSM) in the United States. They assessed postoperative complications, resource utilization, and predictors of costs, in this surgically treated CSM population.

METHODS

MarketScan data (2006–2010) were used to retrospectively analyze the complications and costs of different spine surgeries for CSM. The authors determined outcomes following anterior cervical discectomy and fusion (ACDF), posterior fusion, combined anterior/posterior fusion, and laminoplasty procedures.

RESULTS

The authors identified 35,962 CSM patients, comprising 5154 elderly (age ≥ 65 years) patients (mean 72.2 years, 54.9% male) and 30,808 nonelderly patients (mean 51.1 years, 49.3% male). They found an overall complication rate of 15.6% after ACDF, 29.2% after posterior fusion, 41.1% after combined anterior and posterior fusion, and 22.4% after laminoplasty. Following ACDF and posterior fusion, a significantly higher risk of complication was seen in the elderly compared with the nonelderly (reference group). The fusion level and comorbidity-adjusted ORs with 95% CIs for these groups were 1.54 (1.40–1.68) and 1.25 (1.06–1.46), respectively. In contrast, the elderly population had lower 30-day readmission rates in all 4 surgical cohorts (ACDF, 2.6%; posterior fusion, 5.3%; anterior/posterior fusion, 3.4%; and laminoplasty, 3.6%). The fusion level and comorbidity-adjusted odds ratios for 30-day readmissions for ACDF, posterior fusion, combined anterior and posterior fusion, and laminoplasty were 0.54 (0.44–0.68), 0.32 (0.24–0.44), 0.17 (0.08–0.38), and 0.39 (0.18–0.85), respectively.

CONCLUSIONS

The authors' analysis of the MarketScan database suggests a higher complication rate in the surgical treatment of CSM than previous national estimates. They found that elderly age (≥ 65 years) significantly increased complication risk following ACDF and posterior fusion. Elderly patients were less likely to experience a readmission within 30 days of surgery. Postoperative complication occurrence, and 30-day readmission were significant drivers of total cost within 90 days of the index surgical procedure.

Cervical laminoplasty developments and trends, 2003-2013: a systematic review

OBJECT

Despite extensive clinical experience with laminoplasty, the efficacy of the procedure and its advantages over laminectomy remain unclear. Specific clinical elements, such as incidence or progression of kyphosis, incidence of axial neck pain, postoperative cervical range of motion, and incidence of postoperative C-5 palsies, are of concern. The authors sought to comprehensively review the laminoplasty literature over the past 10 years while focusing on these clinical elements.

METHODS

The authors conducted a literature search of articles in the Medline database published between 2003 and 2013, in which the terms "laminoplasty," "laminectomy," and "posterior cervical spine procedures" were used as key words. Included was every single case series in which patient outcomes after a laminoplasty procedure were reported. Excluded were studies that did not report on at least one of the above-mentioned items.

RESULTS

A total of 103 studies, the results of which contained at least 1 of the prespecified outcome variables, were identified. These studies reported 130 patient groups comprising 8949 patients. There were 3 prospective randomized studies, 1 prospective nonrandomized alternating study, 15 prospective nonrandomized data collections, and 84 retrospective reviews. The review revealed a trend for the use of miniplates or hydroxyapatite spacers on the open side in Hirabayashi-type laminoplasty or on the open side in a Kurokawa-type laminoplasty. Japanese Orthopaedic Association (JOA) scoring was reported most commonly; in the 4949 patients for whom a JOA score was reported, there was improvement from a mean (± SD) score of 9.91 (± 1.65) to a score of 13.68 (± 1.05) after a mean follow-up of 44.18 months (± 35.1 months). The mean preoperative and postoperative C2-7 angles (available for 2470 patients) remained stable from 14.17° (± 0.19°) to 13.98° (± 0.19°) of lordosis (average follow-up 39 months). The authors found significantly decreased kyphosis when muscle/posterior element-sparing techniques were used (p = 0.02). The use of hardware in the form of hydroxyapatite spacers or miniplates did not influence the progression of deformity (p = 0.889). An overall mean (calculated from 2390 patients) of 47.3% loss of range of motion was reported. For the studies that used a visual analog scale score (totaling 986 patients), the mean (cohort size-adjusted) postoperative pain level at a mean follow-up of 29 months was 2.78. For the studies that used percentages of patients who complained of postoperative axial neck pain (totaling 1249 patients), the mean patient number-adjusted percentage was 30% at a mean follow-up of 51 months. The authors found that 16% of the studies that were published in the last 10 years reported a C-5 palsy rate of more than 10% (534 patients), 41% of the studies reported a rate of 5%-10% (n = 1006), 23% of the studies reported a rate of 1%-5% (n = 857), and 12.5% reported a rate of 0% (n = 168).

CONCLUSIONS

Laminoplasty remains a valid option for decompression of the spinal cord. An understanding of the importance of the muscle-ligament complex, plus the introduction of hardware, has led to progress in this type of surgery. Reporting of outcome metrics remains variable, which makes comparisons among the techniques difficult.