Anterior Cervical Corpectomy and Fusion Versus Posterior Laminoplasty for Cervical Oppressive Myelopathy Secondary to Ossification of the Posterior Longitudinal Ligament: A Meta-analysis

Surgical Management of Cervical Ossification of Posterior Longitudinal Ligament: The Treatment Algorithm and Outcome

Introduction Managing patients who present with symptoms of cervical myelopathy secondary to cervical ossification of the posterior longitudinal ligament (OPLL) is challenging. Various factors such as the number of levels involved with OPLL, types of OPLL, canal occupying ratio, K-line characteristics, and C2-C7 lordosis angle were found to guide decision-making and surgical approaches in managing this condition. However, no clear treatment algorithm has been published. This study aims to investigate the outcome of the management of cervical OPLL using a treatment algorithm used in a tertiary university hospital. Methods This is a retrospective cross-sectional study. Patients with cervical myelopathy secondary to cervical OPLL who were treated surgically in our center from 2014 to 2020 were included in this study. Demographic data and preoperative parameters that determined the treatment given according to our treatment algorithm were analyzed. Result A total of 24 patients fit the inclusion and exclusion criteria of the study. The mean recovery rate for all groups is 61.8[Formula: see text]21.9% and the mean postoperative neck disability index (NDI) is 17.83[Formula: see text]16.67%. There was a statistically significant difference between preoperative and postoperative Japanese Orthopaedic Association (JOA) scores for both anterior and posterior surgery subgroups. Conclusion We believe that the treatment algorithm used in our center could benefit other surgeons as a guide in managing patients who suffer from cervical myelopathy secondary to cervical OPLL. Further study including newer techniques would increase the surgeon's arsenal in providing the best outcome in managing this condition.

Comparative Effectiveness and Safety of Anterior Cervical Corpectomy with Fusion, Laminoplasty, and Laminectomy and Instrumented Fusion for Ossification of the Posterior Longitudinal Ligament: A Systematic Review and Network Meta-Analysis

BACKGROUND

To evaluate the comparative effectiveness and safety of anterior cervical corpectomy with fusion (ACCF), laminoplasty (LP), and laminectomy and instrumented fusion (LF) in the treatment of ossification of the posterior longitudinal ligament (OPLL).

METHODS

Embase, Pubmed, and Cochrane library were searched from their date of inception to June 13, 2020. Relevant randomized controlled trials (RCTs) and cohort studies comparing different procedures among ACCF, LP, and LF were identified, data were extracted to perform a network meta-analysis (NMA). The outcomes were the Japanese Orthopedic Association (JOA) score and complications.

RESULTS

We deemed 14 trials eligible, including 877 patients. In NMA, ACCF showed a significant improvement of JOA score compared with LP [MD= -0.89, 95% CI (-1.73, -0.18)], but no significant difference was found when compared LF with ACCF or LP. No significant differences in complications were found when compared LF with LP or ACCF, while ACCF showed significantly higher in complications than LP [OR = 1.99, 95% CI (1.10, 3.35)]. The surface under the cumulative ranking curves (SUCRA) showed that the rank of JOA score improvement is as follows: ACCF (82.5%), LF (79.5%), and LP (2.3%). And the rank of complication rate is as follows: LF (65.8%), ACCF (68.4%), and LP (2.1%).

LIMITATION

The biggest limitation was that none of the included studies were RCTs.

CONCLUSIONS

Despite the higher probability of complications than LP, ACCF was the more recommended procedure for its highest ranking spectrums of JOA score improvement to treat the OPLL.

Exclusion of Ossified Ligaments Behind C2 Vertebra Combined with Anterior Controllable Antedisplacement and Fusion for Cervical Ossification of the Posterior Longitudinal Ligament Extending to C2 Segment

OBJECTIVE

We sought to introduce an anterior surgical technique for cervical ossification of posterior longitudinal ligament (OPLL) extending to C2.

METHODS

A total of 29 patients with multilevel OPLL extending to C2 underwent surgery from January 2016 to January 2019. The rationale of our surgical technique is to transect the ossified ligament at the level of C2/3, dividing OPLL into 2 parts. OPLL behind the C2 vertebra is reserved as "focus exclusion," and OPLL below C2 is performed anterior controllable antedisplacement and fusion. Neurologic condition was evaluated using the Japanese Orthopaedic Association scoring system and its improvement ratio. Radiologic assessment included type and extent of OPLL, occupying rate, thickness and length of ossified mass, and curvature of spinal cord. Surgery- and implant-related complications were recorded.

RESULTS

The mean Japanese Orthopaedic Association score increased from 9.4 to 15.8 points at last follow-up, with a significant improvement (P < 0.01). The mean preoperative length of the ossified mass behind C2 was 15.4 mm, and its thickness was 2.2 mm, with no significant progression at last follow-up (15.3 mm and 2.2 mm, P > 0.05). There was also no statistical difference in OPLL thickness at the largest occupying rate level between preoperation and last follow-up (7.4 mm vs. 7.3 mm, P > 0.05). Four patients presented with cerebrospinal fluid leakage, 1 with screw displacement, and 1 with dysphagia.

CONCLUSIONS

For patients with cervical OPLL extending to C2, exclusion of ossified ligaments behind C2 combined with anterior controllable antedisplacement and fusion below C2 is an effective and alternative technique.

The Clinical Implications and Complications of Anterior Versus Posterior Surgery for Multilevel Cervical Ossification of the Posterior Longitudinal Ligament; An Updated Systematic Review and Meta-Analysis

OBJECTIVE

Theoretically, the optimal approach is determined by the status of ossification of the posterior longitudinal ligament (OPLL) and sagittal alignment. However, there have long been disputes about the optimum surgical approach of OPLL. This study is to compare risk-effectiveness between anterior decompression and fusion (ADF) and laminoplasty and laminectomy with fusion (LP/LF) for the patient with cervical myelopathy due to multilevel cervical OPLL.

METHODS

We searched core databases, and compared complication and outcomes between ADF and LP/LF for patients with multiple OPLL for the cervical spine. The incidence of complications such as neurologic deterioration, C5 palsy, and dura tear was assessed. Changes in JOA score between baseline and final evaluations were assessed for 2 groups. The minimal clinically important difference (MCID) was utilized for evaluating clinical significance. We calculated Peto odds ratio (POR) and mean difference for the incidence and continuous variables, respectively.

RESULTS

We included data from 21 articles involving 3,872 patients with cervical myelopathy with OPLL. Major neurologic deficits such as paraplegia, quadriplegia developed 2.17% in the ADF group and 1.11% in the LP/LF group, and POR was 2.16. Mean difference of JOA score improvement of 2 groups was 1.30, and the mean difference showed a statistical significance. However, 1.3 points of JOA improvement cannot reach 2.5 points of the MCID.

CONCLUSION

Anterior surgery often led to rare but critical complications, and the difference of neurological improvement between 2 groups was below a clinically meaningful level. Posterior surgeries may be appropriate in the treatment of multilevel cervical myelopathy with OPLL.