Outcomes following Laminoplasty or Laminectomy and Fusion in Patients with Myelopathy Caused by Ossification of the Posterior Longitudinal Ligament: A Systematic Review

Assessing Range of Motion Gap in Circumferential Surgery for Cervical Myelopathy due to Ossification of the Posterior Longitudinal Ligament

OBJECTIVE

Only a few studies have investigated the gap range of motion (gROM) in cervical myelopathy or deformity caused by ossification of the posterior longitudinal ligament (OPLL). The aim of this study is to investigate the correlation between the individual gROM and the postoperative clinical outcomes of patients with OPLL.

METHODS

Consecutive patients of cervical myelopathy caused by OPLL were analyzed retrospectively. The clinical outcomes were evaluated using Visual Analogue Scale scores of the neck and arm pain and the Japanese Orthopaedic Association scores. Radiologic measurements included flexion ROM (fROM), which was defined as the difference of cervical lordosis in flexion and neutral positions, extension ROM (eROM), defined as the difference between neutral and extension positions, and gROM, defined as the difference between fROM and eROM. Patients were grouped by the values of gROM, and comparisons of all outcomes were made between the groups.

RESULTS

A total of 42 patients underwent surgery. The patients with greater gROM did not differ from those with smaller gROM by demographic characteristics. During follow-up (mean 45.8 months), both groups had similar improvements, but the C5 palsy rates were higher in the greater gROM group than in the smaller gROM group (71% and 22%, P < 0.05).

CONCLUSIONS

Simultaneous circumferential decompression and fixation is an effective surgical option for patients with cervical myelopathy caused by OPLL. A higher rate of postoperative C5 palsy was observed in the patients with greater gROMs after surgery, although all patients presented with similar clinical improvements.

Management of Cerebrospinal Fluid Leakage by Pump-Regulated Volumetric Continuous Lumbar Drainage Following Anterior Cervical Decompression and Fusion for Ossification of the Posterior Longitudinal Ligament

OBJECTIVE

Cerebrospinal fluid (CSF) leakage is a major concern related to anterior cervical decompression and fusion for ossification of the posterior longitudinal ligament (OPLL). We propose a management algorithm for CSF leakage following anterior cervical decompression and fusion for OPLL involving the use of pump-regulated volumetric continuous lumbar drainage.

METHODS

We retrospectively reviewed patients who underwent anterior cervical decompression and fusion for OPLL and were managed with the proposed algorithm between March 2018 and July 2022. The proposed management algorithm for CSF leakage by pump-regulated volumetric continuous lumbar drainage was as follows. On exposure of the arachnoid membrane with or without CSF leakage, a dural sealant patch was applied to manage the dural defect. In case of persistent CSF leakage despite application of the dural sealant patch, patients underwent pump-regulated volumetric continuous lumbar drainage.

RESULTS

Fifty-one patients were included in the study. CSF leakage occurred in 14 patients. Of these 14 patients, 9 patients underwent lumbar drain insertion according to the proposed management algorithm. Successful resolution of CSF leakage was observed in 8 of the 9 patients who underwent lumbar drainage. All patients were encouraged to ambulate without concern of CSF overdrainage due to gravity, because it could be avoided with pump-regulated volumetric continuous CSF drainage. Therefore, complications associated with absolute bed rest or CSF overdrainage were not observed.

CONCLUSION

The proposed management algorithm with pump-regulated volumetric continuous lumbar drainage showed safety and efficacy for management of CSF leakage following anterior decompression and fusion for OPLL.

Bilateral phrenic nerve palsy after posterior cervical decompression and fusion surgery: a rare event after surgery

INTRODUCTION

Delayed C5 weakness is a known entity in cervical spine surgery, although with varied clinical presentation and poorly understood mechanism of action. We describe the first case in the literature of a bilateral C5 palsy leading to bilateral phrenic nerve dysfunction following a posterior cervical decompression and fusion.

CASE REPORT

A 76-year-old male presented with low back pain and was diagnosed as myelopathic. On initial neurological examination, he could not ambulate without assistance and was unsteady on tandem gait. The initial cervical MRI and CT scan showed advanced multilevel degenerative changes of the cervical spine with severe cord compression and myelomalacia. The patient underwent C3-C6 posterior cervical decompression & fusion (PCDF). He awoke with his baseline examination without neurophysiological monitoring changes intraoperatively or C5 root EMG activity. Post-operative MRI of the cervical spine was performed and showed an excellent decompression. The patient was neurologically stable and discharged to a rehabilitation facility. Patient developed a delayed bilateral C5P on postoperative day (POD) 74. Delayed bilateral C5P and phrenic nerve damage was determined to cause this patient's dyspnea. PM&R consult recommended placement of diaphragmatic pacers. However, clinically his respiratory function, as well as motor deficits, have gradually improved.

CONCLUSION

Bilateral diaphragmatic paralysis, a severe complication of cervical spine surgery, may cause respiratory distress and upper limb weakness. C5P, the underlying cause, may arise from various factors. Early detection and management of diaphragmatic weakness with physical therapy and pacers are crucial, emphasizing the need for vigilance by healthcare professionals and surgeons.

Residual Neuropathic Pain in Postoperative Patients With Cervical Ossification of Posterior Longitudinal Ligament

STUDY DESIGN

A prospective multi-institutional observational study.

OBJECTIVE

To investigate and identify risk factors for residual neuropathic pain after surgery in patients with cervical ossification of posterior longitudinal ligament (c-OPLL).

SUMMARY OF BACKGROUND DATA

Patients with c-OPLL often require surgery for numbness and paralysis of the extremities; however, postoperative neuropathic pain can considerably deteriorate their quality of life.

METHODS

Out of 479 patients identified from multicenter c-OPLL registries between 2014 and 2017, 292 patients who could be followed up for 2 years postoperatively were reviewed, after excluding patients with nervous system comorbidities. Demographic details; medical history; radiographic factors including the K-line, spinal canal occupancy rate of OPLL, cervical kyphosis angle, and presence of spinal cord myelomalacia; preoperative Japanese Orthopaedic Association (JOA) score; surgical procedure (fusion or decompression surgery); postoperative neurological deterioration; and the visual analogue scale for pain and numbness in the upper extremities (U/E) or trunk/lower extremities (L/E) at baseline and at 2 years postoperatively were assessed. Patients were grouped into residual and non-residual groups based on a postoperative visual analogue scale ≥40 mm. Risk factors for residual neuropathic pain were evaluated by multiple logistic regression analysis.

RESULTS

The prevalence of U/E and L/E residual pain in postoperative c-OPLL patients was 51.7% and 40.4%, respectively. The U/E residual group had a poor preoperative JOA score and longer illness duration, and fusion surgery was more common in the residual group than in non-residual group. The L/E residual group was older with a poorer preoperative JOA score. On multivariate analysis, risk factors for U/E residual pain were long illness duration and poor preoperative JOA score, whereas those for L/E residual pain were age and poor preoperative JOA score.

CONCLUSIONS

The risk factors for residual spinal neuropathic pain after c-OPLL surgery were age, long duration of illness, and poor preoperative JOA score.

LEVEL OF EVIDENCE

IV.

The surgical strategy for multilevel massive ossification of the posterior longitudinal ligaments

Purpose

Creating enough decompression, favorable outcome, less complication, and maintain adequate lordosis and stability in the patients with cervical myelopathy due to multilevel massive ossification of the posterior longitudinal ligament (OPLL) still poses a challenge for surgeons. The aim of our study is to retrospectively evaluate our patients and try to seek a better surgical strategy.

Methods

Between 2015 and 2019, 55 consecutive patients with multilevel massive OPLL underwent surgical treatment. Among these, 40 patients were treated with cervical laminectomy and then anterior decompression, fusion, and fixation (ADF), which was defined as group 1, and 15 patients were treated with cervical laminectomy and fixation simultaneously, which was defined as group 2. The patient's radiographic characteristics and postoperative outcomes were evaluated.

Results

Better postoperative cervical sagittal lordosis and less long-term axial pain was achieved in group 1 (p < 0.001), though the functional outcome had no significant difference. In the multivariable analysis, anterior fixation accounts for independent factors for better cervical sagittal alignment (p < 0.001). No complications directly associated with cervical laminectomy were observed.

Conclusion

In patients with cervical multilevel massive OPLL, laminectomy at compression level and then ADF depended on the severity and range of compression, but corpectomy of not more than two vertebral bodies is suggested, except K-line (+) and long-segment massive OPLL majorly involving the C2 and posterior laminectomy above and below the OPLL-affected levels with posterior fixation simultaneously.

Factors affecting titanium mesh cage subsidence in single-level anterior cervical corpectomy and fusion for ossification of the posterior longitudinal ligament

PURPOSE

To analyze risk factors of titanium mesh cage (TMC) subsidence in single-level anterior cervical corpectomy and fusion (ACCF) for cervical ossification of the posterior longitudinal ligament (OPLL).

METHODS

TMC subsidence is defined as the reduction of the adjacent vertebral bodies by ≥ 2 mm. Patients with cervical OPLL who were treated with single-level ACCF between January 2019 and May 2021 were retrospectively analyzed in two groups: patients with TMC subsidence as Group S and patients with no TMC subsidence as Group N during the one-year follow-up period. The degree of distraction of surgical segment and correction of the cervical curvature was measured to analyze their relationship with TMC subsidence.

RESULTS

A total of 128 patients were included in Group S, and 138 patients were included in Group N. There was no significant difference in patient demographics and complications between the two groups. The degree of distraction in Group S was significantly higher than that in Group N (11.4% ± 7.6% vs. 4.7% ± 9.7%, P < 0.01). The change of C2 to C7 Cobb angle (α) in Group S was significantly greater than that in Group N (5.7 ± 2.7 vs. 1.4 ± 4.7, P < 0.01), and the change of interspinous process distance (SPD) in Group S was also significantly greater than that in Group N (7.0 ± 4.2 vs. 4.1 ± 2.7, P < 0.01). The JOA score and JOA recovery rate were not statistically different between the two groups.

CONCLUSIONS

Intraoperative selection of overlength TMC in single-level ACCF for OPLL, over-distraction and excessive correction of the cervical curvature may cause TMC subsidence after surgery. No significant impact of TMC subsidence on the surgical outcome was observed during the 1-year follow-up period.

Ossification of the Posterior Longitudinal Ligament: Pathophysiology, Diagnosis, and Management

Ossification of the posterior longitudinal ligament (OPLL) occurs as heterotopic bone forms in the posterior longitudinal ligament, resulting in neural compression, myelopathy, and radiculopathy. OPLL is most commonly observed in East Asian populations, with prevalence rates of 1.9% to 4.3% reported in Japan. OPLL rates are lower in North American and European patients, with reported prevalence of 0.1% to 1.7%. Patients typically develop symptoms due to OPLL in their cervical spines. The etiology of OPLL is multifactorial, including genetic, metabolic, and anatomic factors. Asymptomatic or symptomatic patients with OPLL can be managed nonsurgically, whereas patients with neurologic symptoms may require surgical decompression from an anterior, posterior, or combined approach. Surgical treatment can provide notable improvement in neurologic function. Surgical decision making accounts for multiple factors, including patient comorbidities, neurologic status, disease morphology, radiographic findings, and procedure complication profiles. In this study, we review OPLL epidemiology and pathophysiology, clinical features, radiographic evaluation, management, and complications.

Cervical Laminoplasty Versus Posterior Laminectomy and Fusion: Trends in Utilization and Evaluation of Complication and Revision Surgery Rates

INTRODUCTION

Cervical laminoplasty (LP) and laminectomy with fusion (LF) are common operations used to treat cervical spondylotic myelopathy. Conflicting data exist regarding which operation provides superior patient outcomes while minimizing the risk of complications. This study evaluates the trends of LP compared with LF over the past decade in patients with cervical myelopathy and examines long-term revision rates and complications between the two procedures.

METHODS

Patients aged 18 years or older who underwent LP or LF for cervical myelopathy from 2010 to 2019 were identified in the PearlDiver Mariner Database. Patients were grouped independently (LP versus fusion) and assessed for association with common medical and surgical complications. The primary outcome was the incidence of LP versus LF for cervical myelopathy over time. Secondary outcomes were revision rates up to 5 years postoperatively and the development of complications attributable to either surgery.

RESULTS

In total, 1,420 patients underwent LP and 10,440 patients underwent LF. Rates of LP (10.5% to 13.7%) and LF (86.3% to 89.5%) remained stable, although the number of procedures nearly doubled from 865 in 2010 to 1,525 in 2019. On matched analysis, LP exhibited lower rates of wound complications, surgical site infections, spinal cord injury, dysphagia, cervical kyphosis, limb paralysis, incision and drainage/exploration, implant removal, respiratory failure, renal failure, and sepsis. Revision rates for both procedures at were not different at any time point.

CONCLUSION

From 2010 to 2019, rates of LP have not increased and represent less than 15% of posterior-based myelopathy operations. Up to 5 years of follow-up, there were no differences in revision rates for LP compared with LF; however, LP was associated with fewer postoperative complications than LF.

LEVEL OF EVIDENCE

Level III retrospective cohort study.

Bridging the cervicothoracic junction during posterior cervical laminectomy and fusion for the treatment of multilevel cervical ossification of the posterior longitudinal ligament: a retrospective case series

BACKGROUND

The purpose of this study was to investigate the surgical efficacy of crossing the cervicothoracic junction during posterior cervical laminectomy and fusion for the treatment of multilevel cervical ossification of the posterior longitudinal ligament (OPLL).

METHODS

From October 2009 to October 2017, 46 consecutive patients with multilevel cervical OPLL underwent posterior cervical laminectomy and crossing the cervicothoracic junction fusion were obtained in the study. Their medical records were retrospectively collected. Cervical lordosis and cervical sagittal balance were used to assess radiographic outcomes. Japanese Orthopedic Association (JOA), axial symptom, C5 root palsy, blood loss, and operation time were used to assess clinical outcomes. The mean follow-up period was 20.7 ± 8.3 months.

RESULTS

The operation time was 205.2 ± 39.8 min and the intraoperative blood loss was 352.2 ± 143.7 ml. Analysis of the final follow-up data showed significant differences in JOA score (P < 0.01), C2-C7 lordosis angle (P < 0.01), and C2-C7 SVA (P < 0.01). CT confirmed that grafted bone was completely fused in all patients and progression of OPLL was observed in two patients (4.3%) at final follow-up. No adjacent segment disease (ASD) or instrument failure occurred in any patients.

CONCLUSIONS

Cervical laminectomy and crossing the cervicothoracic junction fusion are effective and safe methods to treat multilevel cervical OPLL. Randomized controlled studies compared constructs ending at cervical vertebrae or thoracic vertebrae are needed to confirm these results.

Risk factors for poor neurological outcomes after unilateral open-door laminoplasty: an analysis of the characteristics of ectopic bone

Background

The factors affecting neurological outcomes with unilateral open-door laminoplasty have been controversial. The purpose of this study was to evaluate the impact of the characteristics of ectopic bone on poor neurological outcomes after unilateral open-door laminoplasty.

Methods

We retrospectively analyzed the clinical data of 112 patients who underwent unilateral open-door laminoplasty from September 2017 to September 2020. According to the Japanese Orthopedic Association score recovery rate after surgery (Japanese Orthopedic Association recovery rate ≥ 50% and < 50%, respectively), all patients were divided into “poor” and “good” groups. The characteristics of ectopic bone and the position relationship between the open side and ectopic bone (for lateral ossification) in the two groups were compared and analyzed. Univariate and multivariate analyses were used to determine the risk factors for poor neurological outcome.

Results

We identified patients with a mean age of 58.39 years and a mean follow-up of 25.43 months. Sixty (53.6%) patients experienced recovery of poor neurological function. On univariable analysis, significant predictors of poor neurological recovery were occupation rate of spinal canal > 60% (p = 0.000), ossification extending to C2 (p = 0.006), lateral ossification (p = 0.032) and opening side on the ipsilateral side of the ectopic bone (p = 0.011). Multivariate logistic regression analysis revealed that the occupation rate of spinal canal > 60% (P = 0.003), ossification extending to C2 (P = 0.041) and opening the door on the ipsilateral side for lateral ossification (P = 0.013) were independent risk factors for poor prognosis of neurological function.

Conclusions

An occupation ratio > 60% is the most important risk factor. Another one is ossification of the posterior longitudinal ligament extending to C2. Meanwhile, opening the door on the ipsilateral side is indeed a risk factor for lateral ossification. Better neurological function may be obtained by choosing the opposite side of the heterotopic bone as the open side. Therefore, the design of the surgical plan should comprehensively consider these factors.

Combined Anterior and Posterior Decompression With Fusion for Cervical Ossification of the Posterior Longitudinal Ligament

Objective:

Cervical myelopathy caused by ossification of the posterior longitudinal ligament (OPLL) is not uncommon among Asian ethnic groups. Despite reports comparing the pros and cons of anterior- and posterior-only approaches, the optimal management remains debatable. This study aimed to evaluate the outcomes of patients who underwent a combined anterior and posterior approach, simultaneous circumferential decompression and fixation, for cervical OPLL.

Method:

The study retrospectively reviewed patients with OPLL and who underwent circumferential decompression and fixation, combined anterior corpectomy and posterior laminectomy. The clinical outcomes were evaluated by the Visual Analog Scale of neck and arm pain, the Japanese Orthopedic Association scores, Neck Disability Index, and Nurick scores at each time-point of evaluation. Radiological evaluations included plain and dynamic radiographs and computed tomography for every patient within 2 years post-operation. Subgroup analyses were further performed between the groups, with and without intra-operative cerebrospinal fluid (CSF) leakage.

Results:

A total of 41 patients completed the follow-up for more than 2 years (mean = 39.8 months) and were analyzed. Continuous-type OPLL was the most common (44%), followed by segmental (27%), mixed (22%), and localized types (7%) in the cohort. Myelopathy and all other functional outcomes improved significantly at 2 years post-operation (all p < 0.05). There were 13 (32%) patients who had intra-operative CSF leakage. At 2 years post-operation, there were no differences in the demographics, functional outcomes, and complication rates between the CSF-leakage and no-leakage groups. The CSF-leakage group had more patients with continuous-type OPLL than the no-leakage group (77 vs. 29%, p = 0.004 < 0.05). During the follow-up, there was no secondary or revision surgery for pseudomeningocele, pseudarthrosis, or other surgery-related complications.

Conclusions:

Simultaneous circumferential decompression and fixation combine the surgical benefits of sufficient decompression by the posterior approach and direct decompression of OPLL by the anterior approach. It is an effective surgical option for patients with cervical myelopathy caused by OPLL, given that myelopathy unanimously improved without neurological complications in this study. The fusion rates were high, and reoperation rates were low. Despite higher rates of CSF leakage, there were no related long-term sequelae, and minimal wound complications.

Comparison of Anterior Cervical Discectomy and Fusion with Cervical Laminectomy and Fusion in the Treatment of 4-Level Cervical Spondylotic Myelopathy

Objective

To assess and compare the therapeutic effects of Anterior Cervical Discectomy and Fusion (ACDF) and Cervical Laminectomy and Fusion (CLF) in the treatment of 4‐level cervical.

Methods

We performed a retrospective review on 39 patients with 4‐level CSM who underwent ACDF or CLF in the Third Hospital of Hebei Medical University from January 2010 to December 2018. The patients were divided into ACDF group and CLF group according to the treatment. The operative index was evaluated based on intraoperative blood loss and operation time. The functional outcomes including Japanese Orthopedic Association (JOA) score and visual analogue scale (VAS) of axial pain were compared. The Cobb angle, Cobb angle improvement rate, range of motion (ROM) and ROM loss ratio were measured for radiographic evaluation.

Results

No major complications or deaths occurred. The average age at baseline was 55 years. There was no significant difference between the ACDF and CLF group in follow‐up time (26.29 months, 25.39 months, P > 0.05). The intraoperative blood loss was higher in the CLF group than in the ACDF group (692.67 ± 38.68 vs 392.14 ± 128.06, P < 0.05). The operation time was longer in the CLF group than in the ACDF group (206.60 ± 49.37 vs 172.64 ± 31.96, P < 0.05). Significant improvements in the VAS and JOA scores were observed in both groups (P < 0.05). No significant difference in VAS was found between the ACDF and CLF groups (P < 0.05). There was a significantly larger improvement rate of JOA score in the ACDF group than in the CLF group (60.9% ± 9.57% vs 31.5% ± 15.70%, P < 0.05). There were two (9.6%) cases with complications In the ACDF group, including one (4.8%) case of dysphagia and one (4.8%) case of pharyngodynia. In the CLF group, two patients (11.1%) developed C₅ palsy. No significant difference in the incidence of complications, ROM loss ratio and Cobb angle improvement rate was found between group ACDF and group CLF (all P < 0.05).

Conclusion

Both ACDF and CLF were effective in the treatment of multi‐level cervical spondylosis and ACDF is more suitable for patients with 4‐level CSM.

Neurological improvement is associated with neck pain attenuation after surgery for cervical ossification of the posterior longitudinal ligament

Although favourable surgical outcomes for myelopathy caused by cervical ossification of the posterior longitudinal ligament (OPLL) have been reported, factors significantly associated with post-operative neck pain attenuation still remain unclear. The primary aim of the present study was to determine factors significantly associated with post-operative neck pain attenuation in patients with cervical OPLL using a prospective multi-centre registry of surgically treated cervical OPLL. Significant postoperative neck pain reduction (50% reduction of neck pain) was achieved in 31.3% of patients. There was no significant difference in neck pain attenuation between surgical procedures. Statistical analyses with univariate analyses followed by stepwise logistic regression revealed neurological recovery as a factor having a significant positive association with post-operative neck pain attenuation (p = 0.04, odds ratio 5.68 (95% confidence interval: 1.27-22.2)). In conclusion, neurological recovery was an independent factor having a significant positive association with post-operative neck pain attenuation in patients with cervical myelopathy caused by OPLL who underwent cervical spine surgery.

Laminoplasty-an underutilized procedure for cervical spondylotic myelopathy

BACKGROUND CONTENT

Cervical laminoplasty (LP) and laminectomy and fusion (LF) are commonly used surgical techniques for cervical spondylotic myelopathy (CSM). Several recent studies have demonstrated superior perioperative metrics and decreased overall costs with LP, yet LF is performed far more often in the United States.

PURPOSE

To determine the percentage of patients with CSM who are radiographically candidates for LP.

STUDY DESIGN

Retrospective comparative cohort study.

PATIENT SAMPLE

Patients >18 years old who underwent LF or LP for CSM at 2 large academic institutions from 2017 to 2019.

OUTCOME MEASURES

Candidacy for LP based on radiographic criteria.

METHODS

Radiographs were assessed by 2 spine surgeons not involved in the care of the patients to determine the C2-C7 Cobb angle and the presence and extent of cervical instability. Patients with kyphosis >13°, > 3.5 mm of listhesis on static imaging, or > 2.5 mm of motion on flexion-extension or standing-supine films were not considered candidates for LP. Intraclass coefficient (ICC) was calculated to assess the interobserver reliability of angular measurements and the presence of instability. The percentage of patients for whom LP was contraindicated was calculated.

RESULTS

One hundred eight patients underwent LF while 142 underwent LP. Of the 108 patients who underwent LF, 79.6% were radiographically deemed candidates for LP, as were all 142 patients who underwent LP. The ICC for C2-C7 alignment was 0.90; there was 97% agreement with respect to the presence of instability.

CONCLUSIONS

In 250 patients with CSM, 228 (91.2%) were radiographically candidates for LP. These data suggest that LP may be an underutilized procedure for the treatment for CSM.

Getting Down to the Bare Bones: Does laminoplasty or laminectomy With Fusion Provide Better Outcomes for Patients With Multilevel Cervical Spondylotic Myelopathy?

Objective

Cervical spondylotic myelopathy (CSM) is a degenerative disorder leading to progressive decline in spinal cord function. Cervical laminoplasty (CLP) and cervical laminectomy with fusion (CLF) are standard treatments for multilevel CSM. However, it is still unclear whether one procedure over the other provides better outcomes. Here, we performed a comprehensive review of published articles that compare the clinical outcomes and costs between CLP and CLF for CSM.

Methods

A literature search was performed using PubMed, Web of Science, and Cochrane databases. Strict exclusion criteria were applied, and included articles were then assessed for publication year, study design, and significant differences in outcome variables.

Results

From 519 studies identified with search terms, 38 studies were included for the qualitative analysis. Statistically significant differences in the clinical outcomes and costs were found in 18 studies. Eleven studies were prospective or retrospective, and 8 studies were meta-analyses. For the outcome variables of interest, results were reported by classifying into prospective studies, retrospective studies, and meta-analyses.

Conclusion

CLP and CLF are 2 of the most commonly performed surgical procedures for the treatment of CSM. Although CLP and CLF each provide satisfactory clinical outcomes for patients with CMS, CLP may result in better cervical range of motion and less cost, length of stay, operation time, blood loss, paraspinal muscular atrophy, and rate of nerve palsies as compared to CLF. The major limitation of CLP versus CLF comparison studies includes the heterogeneity in techniques and preoperative criteria. Thus, further validation and investigations in larger cohorts will be required.

Choice of the Open Side in Unilateral Open-Door Laminoplasty for Cervical Ossification of the Posterior Longitudinal Ligament

STUDY DESIGN

Retrospective study.

OBJECTIVE

To determine the optimal open side in unilateral open-door laminoplasty (UODL) for lateral cervical ossification of posterior longitudinal ligament (OPLL).

SUMMARY OF BACKGROUND DATA

No literature has reported which side of the vertebral arch should be chosen as the open side in UODL for lateral cervical OPLL.

METHODS

Patients with lateral cervical OPLL who were treated with UODL between 2013 and 2018 were retrospectively analyzed in two groups: Group A, where the open side was contralateral to the ectopic bone, and Group B, where the open side was ipsilateral to the ectopic bone. The Japanese Orthopaedic Association (JOA) Score, JOA recovery rate, spinal canal enlargement rate, cervical range of motion (ROM), and spinal cord area (SCA) were measured to evaluate and compare the clinical outcomes between the two groups. Statistical analysis was performed by t test and Hotelling T2 test.

RESULTS

There was no significant difference in patient demographics and major complications between the two groups. The postoperative JOA Score and JOA recovery rate in Group A were significantly higher than those in Group B. There was no significant difference in cervical ROM within or between the two groups during the 2-year follow-up period, nor was there significant difference in spinal canal enlargement between the two groups. However, both postoperative SCA and increased SCA in Group A were significantly higher than those in Group B.

CONCLUSION

The contralateral open side approach is preferable to the ipsilateral open side approach in UODL for lateral cervical OPLL.

LEVEL OF EVIDENCE

3.

National Trends and Complications in the Surgical Management of Ossification of the Posterior Longitudinal Ligament (OPLL)

STUDY DESIGN

A retrospective database analysis.

OBJECTIVE

The aim of this study was to analyze US trends in surgical approaches for ossification of the posterior longitudinal ligament (OPLL); and to compare US patient and hospital characteristics, length of stay, total charges, and 30-day complications by surgical approach in OPLL management.

SUMMARY OF BACKGROUND DATA

A robust literature on surgical management of OPLL in East Asian countries, where OPLL has a higher prevalence, exists. However, there is a paucity of literature evaluating the surgical management of OPLL in non-Asian countries.

METHODS

Using the Nationwide Inpatient Sample (NIS), we identified surgically treated OPLL patients from 2003 to 2014. Data on patient characteristics, surgical approaches, complications, hospital characteristics, length of stay, and hospital charges were extracted and analyzed. Analysis of variance (ANOVA) and Chi-squared tests were used to assess variation across categorical variables. Linear regression was used to evaluate the trend of surgical management for OPLL over the study timeframe.

RESULTS

Five thousand two hundred twelve patients fit our inclusion criteria. The overall complication rate was 21.5%, but the highest complication rate was for patients undergoing a combined anterior-posterior decompression/fusion (44.7%). Patients undergoing a combined anterior-posterior decompression/fusion had a longer length of stay and higher total charges (P < 0.01). Overall, surgical OPLL cases significantly increased from 2003 to 2014 (336-920; P < 0.01).

CONCLUSION

To our knowledge, this is the largest study examining the surgical treatment of OPLL in a non-Asian country. OPLL surgical cases increased over the study timeframe and the overall surgical complication rate was 21.5%. The percentage of Asians or Pacific Islanders with OPLL undergoing surgical intervention was 10.8%, which is higher than the prevalence in the US population (4.9%). This suggests a potential genetic component to OPLL. Future work is warranted to determine how best to decrease the high complication rate.

LEVEL OF EVIDENCE

4.

Outcomes of posterior cervical fusion and decompression: a systematic review and meta-analysis

BACKGROUND CONTEXT

Posterior cervical fusion (PCF) with decompression is a treatment option for patients with conditions such as spondylosis, spinal stenosis, and degenerative disc disorders that result in myelopathy or radiculopathy. The annual rate, number, and cost of PCF in the United States has increased. Far fewer studies have been published on PCF outcomes than on anterior cervical fusion (ACF) outcomes, most likely because far fewer PCFs than ACFs are performed.

PURPOSE

To evaluate the patient-reported and clinical outcomes of adult patients who underwent subaxial posterior cervical fusion with decompression.

STUDY DESIGN/SETTING

Systematic review and meta-analysis.

PATIENT SAMPLE

The total number of patients in the 31 articles reviewed and included in the meta-analysis was 1,238 (range 7-166).

OUTCOME MEASURES

Preoperative to postoperative change in patient-reported outcomes (visual analog scales for arm pain and neck pain, Neck Disability Index, Japanese Orthopaedic Association [JOA] score, modified JOA score, and Nurick pain scale) and rates of fusion, revision, and complications or adverse events.

METHODS

This study was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and a preapproved protocol. PubMed and Embase databases were searched for articles published from January 2001 through July 2018. Statistical analyses for patient-reported outcomes were performed on the outcomes' raw mean differences, calculated as postoperative value minus preoperative value from each study. Pooled rates of successful fusion, revision surgery, and complications or adverse events, and their 95% confidence intervals, were also calculated. Two subgroup analyses were performed: one for studies in which only myelopathy or radiculopathy (or both) were stated as surgical indications and the other for studies in which only myelopathy or ossification of the posterior longitudinal ligament (or both) were stated as surgical indications. This study was funded by Providence Medical Technology, Inc. ($32,000).

RESULTS

Thirty-three articles were included in the systematic review, and 31 articles were included in the meta-analysis. For all surgical indications and for the 2 subgroup analyses, every cumulative change in patient-reported outcome improved. Many of the reported changes in patient-reported outcome also exceeded the minimal clinically important differences. Pooled outcome rates with all surgical indications were 98.25% for successful fusion, 1.09% for revision, and 9.02% for complications or adverse events. Commonly reported complications or adverse events were axial pain, C5 palsy, transient neurological worsening, and wound infection.

CONCLUSIONS

Posterior cervical fusion with decompression resulted in significant clinical improvement, as indicated by the changes in patient-reported outcomes. Additionally, high fusion rates and low rates of revision and of complications and adverse events were found.

Ossification of the Posterior Longitudinal Ligament: Surgical Approaches and Associated Complications

Ossification of the posterior longitudinal ligament (OPLL) is a rare but potentially devastating cause of degenerative cervical myelopathy (DCM). Decompressive surgery is the standard of care for OPLL and can be achieved through anterior, posterior, or combined approaches to the cervical spine. Surgical correction of OPLL via any approach is associated with higher rates of complications and the presence of OPLL is considered a significant risk factor for perioperative complications in DCM surgeries. Potential complications include dural tear (DT) and subsequent cerebrospinal fluid leak, C5 palsy, hematoma, hardware failure, surgical site infections, and other neurological deficits. Anterior approaches are technically more demanding and associated with higher rates of DT but offer greater access to ventral OPLL pathology. Posterior approaches are associated with lower rates of complications but may allow for continued disease progression. Therefore, the decision to pursue either an anterior or posterior approach to surgical decompression may be critically influenced by complications associated with each procedure. The authors critically review anterior and posterior approaches to surgical decompression of OPLL with particular focus on the complications associated with each approach. We also review the recent work in developing new surgical treatments for OPLL that aim to reduce complication incidence.

Incidence and Outcomes of C5 Palsy and Axial Pain After Open-Door Laminoplasty or Laminectomy and Fusion: A Meta-Analysis

OBJECTIVE

C5 palsy and axial pain are significant factors affecting the quality of life after posterior cervical surgery; however, there has been no clear and supportive conclusion on which method is more suitable in a certain case. As a result, we compare the clinical outcomes, complication rates, and anatomical changes between open-door laminoplasty (ODL) and laminectomy and fusion (LF) for cervical spondylotic myelopathy. This is a systematic literature review and meta-analysis.

METHODS

A comprehensive literature search was conducted using PubMed, Embase, and the Cochrane library. The following outcomes were extracted and analyzed: the cases of C5 palsy and axial pain patients, Japanese Orthopaedic Association, range of motion (ROM), and cervical curvature. Data analysis was conducted with RevMan 5.3. The I² statistics were used to evaluate heterogeneity.

RESULTS

A total of 9 studies were included in the final analysis, all of which were prospective or retrospective cohort studies. The pooled data showed that the incidences of C5 palsy and axial pain in LF were higher than those in ODL. The study indicated that there was no significant difference in pre- and postoperative Japanese Orthopaedic Association scores, preoperative cervical ROM, pre- and postoperative cervical curvature between the 2 groups, but there was significant difference in ROM after operation. These results indicate that ODL was superior to LF in maintaining cervical ROM.

CONCLUSIONS

Our results demonstrate that the lower incidence of C5 palsy and axial pain can be achieved by using ODL compared with LF. However, current data only provide weak support, if any, favoring ODL over for clinical improvement in reduce these 2 complications.

Clinical Impact of Ossification of the Posterior Longitudinal Ligament Progression After Cervical Laminoplasty

STUDY DESIGN

This is a retrospective study.

OBJECTIVES

(1) To analyze the incidence of second surgery after initial laminoplasty for ossification of the posterior longitudinal ligament (OPLL) due to disease progression, (2) to examine factors associated with poor surgical outcome.

SUMMARY OF BACKGROUND DATA

Neurological deterioration after laminoplasty is frequently encountered due to OPLL progression.

PATIENTS AND METHODS

Of 201 OPLL patients treated by laminoplasty at a single-institution, the 153 monitored for >3 years postsurgery were included in this analysis. Neurological findings were graded by the Japanese Orthopaedic Association (JOA) score. We retrospectively examined the incidence of second surgery due to OPLL progression. We also evaluated the clinical characteristics and the surgical outcomes after second operation to identify potential risk factors for poor outcome.

RESULTS

Eight patients required a second surgery due to OPLL progression. Neurological recovery was achieved in 5 of these patients, whereas 3 exhibited continued dysfunction. Patients with poor recovery showed kyphotic changes of spinal alignment and high-intensity regions in the spinal cord on T2-weighted magnetic resonance images (T2-MRI).

CONCLUSIONS

Only a small fraction of OPLL patients required a second surgery due to OPLL progression. Recovery was poor in those with clear high-intensity T2-MRI signals in the spinal cord.

Comparison of laminoplasty versus laminectomy and fusion in the treatment of multilevel cervical ossification of the posterior longitudinal ligament: A systematic review and meta-analysis

BACKGROUND

Laminoplasty (LP) and laminectomy with fusion (LF) were recognized as two reliable and effective way in treating multilevel cervical ossification of the posterior longitudinal ligament (OPLL). However, there was no clear conclusion on which method is better. A meta-analysis was conducted to evaluate the clinical results between LP and LF in the treatment of multilevel cervical OPLL.

METHODS

An extensive search of literature was performed in PubMed, Embase, the Cochrane library, CNKI (Chinese database), and WANFANG (Chinese database). The following outcomes were extracted: the Japanese Orthopedic Association (JOA) scores, visual analog scale (VAS), cervical lordosis, cervical range of motion (ROM), complications, blood loss, and operation time. Data analysis was conducted with RevMan 5.3.

RESULTS

A total of 11 studies were included in the final analysis. The results indicated that no significant differences between LP and LF group in terms of preoperative JOA scores (P = .58), postoperative JOA scores (P = .60), JOA scores improvement rate (P = 0.64), preoperative VAS (P = .34), postoperative VAS (P=.20), preoperative range of motion (ROM) (P = .10), postoperative ROM (P = .18), preoperative cervical lordosis (P = .56), C5 palsy (P = .16), and axial pain (P = .21). LF group showed larger postoperative cervical lordosis than LP group [standardized mean difference (SMD) = 1.13 (2.03, 0.24), P = .01]. However, LP group showed lower operation time [mean difference (MD) = 19.42 (26.87, 11.97), P < .001] and blood loss [MD = 94.78 (179.05, 10.51), P = .03] than LF group.

CONCLUSION

Both LP and LF can achieve clinical improvement in the treatment of multilevel cervical OPLL. LF was superior to LP in maintaining cervical lordosis. However, LP showed lower surgical trauma than LF. Kyphosis line (K-line) may be a good criterion in the selection of posterior surgery. LP was performed for the patients with K-line (+) and LF for K-line (-).

Risk Factors for Significant Intraoperative Blood Loss During Unilateral Expansive Open-Door Cervical Laminoplasty for Cervical Compressive Myelopathy

OBJECTIVE

Unilateral expansive open-door cervical laminoplasty is an effective and safe procedure for cervical compressive myelopathy but occasionally is accompanied with significant intraoperative blood loss (SIBL). The aim of the present study was to elucidate the risk factors for SIBL in patients undergoing cervical laminoplasty for multilevel cervical compressive myelopathy and to identify the effect of SIBL on neurologic complications.

METHODS

A total of 215 patients who received cervical laminoplasty between January 2010 and August 2016 were enrolled in the study. SIBL was defined as 500 mL or more of blood volume during surgery. Patients were subdivided into 2 groups according to whether they suffered from SIBL (n = 26) or not (n = 189). Patient characteristics and clinical data were collected. Univariate and multivariable analysis were performed to identify independent risk factors for SIBL.

RESULTS

The incidence of SIBL during unilateral expansive open-door cervical laminoplasty was 12.1%. The multivariable logistic regression analysis showed Pavlov ratio (odds ratio [OR] 0.002, P = 0.009), ossification of the posterior longitudinal ligament (OR 2.677, P = 0.038), and number of complete hinge fractures (OR 1.842, P = 0.015) were independent risk factors for SIBL during cervical laminoplasty. Patients with SIBL during cervical laminoplasty had a greater rate of neurologic complications during hospitalization (P = 0.012), worse neurologic recovery rate at discharge (P = 0.01), and longer postoperative length of stay (P = 0.003).

CONCLUSIONS

This study suggested that Pavlov ratio, ossification of the posterior longitudinal ligament, and number of complete hinge fractures were independent risk factors for SBIL during cervical laminoplasty. SIBL in cervical laminoplasty was associated with greater neurologic complications and worse neurologic functional recovery.

Comparing effects of cervical anterior approach and laminoplasty in surgical management of cervical ossification of posterior longitudinal ligament by a prospective nonrandomized controlled study

INTRODUCTION

The laminoplasty has been the most widely used surgical method for OPLL. In recent years, increasing attention has been drawn to the anterior operative approaches for surgical treatment of cervical OPLL. However, which method is the optimum selection for therapy of cervical OPLL is still obscure. Therefore, we performed this prospective nonrandomized clinical study in patients with multilevel cervical myelopathy due to OPLL and compare the therapeutic efficiency of laminoplasty and anterior approach (cervical discectomy and/or cervical corpectomy) in the management of multilevel cervical OPLL.

HYPOTHESIS

There is no difference in clinical effects between anterior cervical spine surgery and laminoplasty in the treatment of multilevel cervical OPLL.

MATERIAL AND METHODS

A total of 150 consecutive patients with multilevels of cervical OPLL underwent anterior approaches (ACDF, ACCF and HDF) from July 2010 to June 2014, which were enrolled in this study. During the same period, one hundred and two patients receiving the laminoplasty were enrolled in the study. The clinical effects, alignment and range of motion (ROM) of cervical spine in patients of the anterior group and posterior group were assessed, respectively. The effects of high signals in T2 weighed MRI scans and percentage of spinal canal stenosis in these patients were also evaluated. Finally, postoperative complications regarding each group were analyzed.

RESULTS

Although significant differences in types of OPLL and preoperative sagittal alignment of cervical spine occurred in the two groups (P<0.05), clinical effects of the two groups were similar (P>0.05). The cervical curvature in laminoplasty group showed significant decrease at final follow-up (P<0.05). For ROM of cervical spine, no significant alteration was observed in both groups. The high T2 weighed signals and rate of spinal canal stenosis can influence clinical effects of both anterior group and laminoplasty group. In addition, significantly higher complication rate was observed in laminoplasty group compared with anterior group (P<0.05).

DISCUSSION

Both anterior and laminoplasty approaches can be considered effective and safe procedures in the treatment of the multilevel OPLL. However, the anterior approach with relatively lower incidence of postoperative complications is a better choice for cases with poor cervical curvature and serious spinal canal stenosis.

TYPE OF STUDY AND LEVEL OF PROOF

Level 3 nonrandomized, controlled clinical trials.

Surgical interventions for cervical spondylosis due to ossification of posterior longitudinal ligament: A meta-analysis

BACKGROUND

Aim of this study was to evaluate the effectiveness of various surgical interventions for the management of cervical spondylosis due to the ossification of posterior longitudinal ligament (OPLL).

METHODS

After a comprehensive literature search in electronic databases, studies were selected by following pre-determined eligibility criteria. Random effects meta-analyses were performed to estimate the effect sizes of various surgical approaches in improving Japanese Orthopedic Association (JOA) scores at latest follow-up and meta-regression analyses were carried out to examine the factors affecting the change in JOA score.

RESULTS

Twenty-three studies [1576 patients; 57.83 (95% confidence interval, 95% CI: 55.98-59.68] years of age; and 73 (70-76) % males; follow-up 55.4 ± 25.7 (range 12-170) months] were included in the meta-analysis. All surgical interventions significantly (P < .00001) improved JOA score. Anterior surgical approaches had an effect size of 4.80 [4.10-5.50] and posterior approaches with laminectomy and laminoplasty improved JOA score by 3.57 [2.39-4.75] and 3.99 [3.65-4.32], respectively. Improvement in JOA score was significantly inversely related to the preoperative JOA score (P < .00001). Surgical interventions did not significantly affect cervical lordosis at the latest follow-up.

CONCLUSION

Surgical interventions for cervical spondylosis due to OPLL significantly improve JOA score as observed at the latest follow-up and this is found to be significantly inversely associated with preoperative JOA score.