Effect of posterior decompression and lateral mass screws fi xation on cervical disc herniation

Objective To explore the clinical effect of posterior laminectomy and lateral mass screw-rod system internal fi xation in the treatment of cervical disc herniation. Methods A retrospective analysis of clinical data about 31 patients with cervical disc herniation from January 2015 to December 2017 in our department was performed. All patients had undergone posterior laminectomy and mass screw-rod system internal fi xation. The Japanese Orthopaedic Association Scores (JOA) and neck disability index (NDI)were applied to evaluate the neurological function and neck/shoulder axial pain before and after surgery respectively. The dural sac and degree of spinal cord shifting were measured by MRI, and the cervical curvature change was evaluated by the combination of Borden method and C2-C7 Cobb angle measurement. Results Totally 31 patients were followed up for 8-20 months, and the average follow-up time was 12 months. Among them, there were 23 males and 8 females with an average age of 46 years old (range, 32-64). There were significant differences between post- and pre-operative JOA score (10.3 vs 6.2, P=0.038) and NDI score (19.3 vs 5.2, P=0.029). The anteroposterior diameter at the level of maximum compression of the dural sac in MRI was 69.2%, which was higher than that before operation, and the mean cervical spinal cord posterior shift was (4.6±1.2) mm with significant differences when compared with before operation (P=0.031). Conclusion Posterior decompression plus lateral mass screws fi xation can relieve symptoms of cervical spinal cord compression, prevent spinal cord ischemic degeneration, restore cervical nerve function and cervical physiological curvature, and relieve cervical axial pain.