An Age-old Debate: Anterior Versus Posterior Surgery for Ossification of the Posterior Longitudinal Ligament

Deep learning for identifying cervical ossification of the posterior longitudinal ligament: a systematic review and meta-analysis

Background

Ossification of the posterior longitudinal ligament (OPLL) is a significant contributor for unintentional durotomy following anterior spinal surgery, neural compression, and cervical myelopathy. While traditional diagnostic methods like plain radiography are commonly used, they may yield false negatives. The diagnostic accuracy and reliability of artificial intelligence methods for detecting this condition remain largely unexplored. This study aimed to systematically evaluate the performance of deep learning models (DLMs) in diagnosing and predicting cervical OPLL.

Methods

This systematic review assesses the utilization of DLMs in diagnosing and predicting OPLL. Inclusion criteria were defined as the use of DLM for the diagnosis and prediction of cervical OPLL in adult patients. Databases included PubMed, Google Scholar, Cochrane Library, ScienceDirect, and BASE. The risk of bias was assessed using the QUADAS-2 tool.

Results

Seven studies with a pooled sample size of 3,373 patients were included. The pooled accuracy, area under the curve, sensitivity, and accuracy are 0.93, 0.92, 0.88, and 0.9. DLM demonstrated superior diagnostic performance, outperforming human comparator groups in terms of sensitivity (0.86 vs. 0.77), specificity (0.98 vs. 0.74), and accuracy (0.89 vs. 0.76). The meta-analysis with a pooled sample size of 1,016 patients revealed the highest proportion of right-identified OPLL subtypes in the mixed- and continuous subtypes (0.93 and 0.87). Accuracy and sensitivity of DLM were higher in the upper compared to the lower cervical spine.

Conclusions

Despite limitations in methodological variations and deep learning challenges, the findings support integrating these models into diagnostic protocols. Their robust performance suggests potential value in clinical practice, offering improved diagnostic accuracy and enhanced subtype differentiation.

Postoperative C5 Palsy after Anterior or Posterior Decompression for Degenerative Cervical Myelopathy: A Subgroup Analysis of the Multicenter, Prospective, Randomized, Phase III, CSM-Protect Clinical Trial

STUDY DESIGN

Retrospective cohort study of prospectively accrued data.

OBJECTIVE

To evaluate a large, prospective, multicentre dataset of surgically treated degenerative cervical myelopathy (DCM) cases on the contemporary risk of C5 palsy with surgical approach.

SUMMARY OF BACKGROUND DATA

The influence of surgical technique on postoperative C5 palsy after decompression for DCM is intensely debated. Comprehensive, covariate-adjusted analyses are needed using contemporary data.

METHODS

Patients with moderate to severe DCM were prospectively enrolled in the multicenter, randomized, Phase III CSM-Protect clinical trial and underwent either anterior or posterior decompression between Jan 31, 2012 and May 16, 2017. The primary outcome was the incidence of postoperative C5 palsy, defined as the onset of muscle weakness by at least one grade in manual muscle test at the C5 myotome with slight or absent sensory disruption after cervical surgery. Two comparative cohorts were made based on the anterior or posterior surgical approach. Multivariate hierarchical mixed-effects logistic regression was used to estimate odds ratios (OR) with 95% confidence intervals (CI) for C5 palsy.

RESULTS

A total of 283 patients were included, and 53.4% underwent posterior decompression. The total incidence of postoperative C5 palsy was 7.4% and was significantly higher in patients who underwent posterior decompression compared with anterior decompression (11.26% vs. 3.03%, P =0.008). After multivariable regression, the posterior approach was independently associated with greater than four times the likelihood of postoperative C5 palsy ( P =0.017). Rates of C5 palsy recovery were comparable between the two surgical approaches.

CONCLUSION

The odds of postoperative C5 palsy are significantly higher after posterior decompression compared to anterior decompression for DCM. This may influence surgical decision-making when there is equipoise in deciding between anterior and posterior treatment options for DCM.

LEVEL OF EVIDENCE

Therapeutic Level-II.

Effectiveness of nasotracheal intubation in anterior cervical surgery including C3 lesions

OBJECTIVE

Anterior approach cervical surgery is widely used for accessing C3 lesions. When operating with an anterior approach, the surgical field is obstructed by mandible. Neck extension is popular method to secure better surgical field but risk devastating neurological damage. To overcome this limited surgical field without neck extension, we adopted nasotracheal intubation and evaluated its efficiency.

METHODS

We retrospectively analyzed 16 patients who underwent anterior cervical discectomy or corpectomy of C3 lesions via nasotracheal intubation. We enrolled an additional 29 patients who underwent anterior cervical discectomy or corpectomy of C3 lesions via orotracheal intubation as a control group. All patients had been diagnosed with cervical spondylotic myelopathy or ossification of the posterior longitudinal ligament. We measured the mandibular-cervical angle, which is the angle between the lower mandibular line and anterior vertebral line.

RESULTS

The mandibular-cervical angle was increased by 7.3 with nasotracheal intubation compared to orotracheal intubation.

CONCLUSIONS

Nasotracheal intubation is an effective surgical option for securing the surgical field without neck extension in anterior cervical surgery including C3 lesions.

Laminectomy with instrumented fusion vs. laminoplasty in the surgical treatment of cervical ossification of the posterior longitudinal ligament: A multicenter retrospective study

Laminectomy with instrumented fusion (LF) has demonstrated better prevention of ossification of posterior longitudinal ligament (OPLL) growth compared to laminoplasty (LP). There remains uncertainty, however, as to which surgical approach is more beneficial with respect to clinical outcomes and complications. We retrospectively reviewed 273 cervical OPLL patients of more than 3 levels, from the two institutions' databases, who underwent LF or LP between January 1998 and January 2016. Each 273 patient (85 with LF, 188 with LP) was assessed for postoperative neurologic and radiologic outcomes, complications and reoperations. The mean length of follow-up was 40.11 months. There were baseline differences between cohorts. Overall, postoperative JOA recovery rate at last follow up was significantly better in the LP group with similar improvement in visual analog neck score. Postoperative C2-7 Cobb angle was decreased compared to baseline for both LF and LP cohorts, but there was no significant difference between groups. Complications occurred in 19 (22.35%) LF patients, and 11 (5.85%) LP patients, with higher incidence of C5 palsy and instrumentation failure in the LF group. Four LF patients (4.71%) and five LP patients (2.66%) underwent reoperation during the follow up period.

Clinical and radiological outcomes of multilevel cervical laminoplasty versus three-level anterior cervical discectomy and fusion in patients with cervical spondylotic myelopathy

Background

Cervical spondylotic myelopathy (CSM) is one of the most common causes of spinal cord impairment in elderly patients. However, a consensus has yet to be reached on the ideal method of surgical intervention. In this study, we investigated serial changes of radiological findings after three-level anterior cervical discectomy and fusion (ACDF) and multilevel laminoplasty and attempted to identify the radiological parameters affecting long-term clinical outcomes in CSM.

Methods

Of the 152 patients with multilevel CSM treated with three-level ACDF and multilevel laminoplasty, 42 had complete radiological parameters both before and 2 years after surgery (three-level ACDF, 22 patients; multilevel laminoplasty, 20 patients). Radiological parameters included spinal cord signal intensity (SI) changes on magnetic resonance imaging (MRI). Clinical outcomes including the Japanese Orthopaedic Association (JOA) score, neck disability index (NDI), Oswestry disability index (ODI), and 36-Item Short Form Health Survey score were measured.

Results

The ACDF group showed significant restoration of segmental lordosis postoperatively (preoperatively: 2.21°, 6 months: 8.37°, P=0.026), and segmental and cervical range of motion (ROM) was markedly reduced and well maintained until the final follow-up (preoperatively: 25.48°, 24 months: 4.35°, P<0.001; preoperatively: 41.71°, 24 months: 20.18°, P<0.001). The recovery rates of the JOA score were 42.85% and 57.40% in the ACDF and laminoplasty groups, respectively, although this difference was not statistically significant. Multivariate regression analysis demonstrated that signal change on MRI significantly affected the recovery rate (P=0.003). The visual analog scale (VAS) score and NDI decreased considerably only in the laminoplasty group, and device complications were confirmed only in the ACDF group (incidence rate =36.5%).

Conclusions

Multilevel laminoplasty showed better radiological and similar clinical outcomes. ACDF had more surgical complications. Spinal cord SI change on preoperative MRI was the independent risk factor for poor clinical outcomes. We recommend laminoplasty instead of three-level ACDF to treat multilevel CSM.