[Comparison of three different posterior cervical approaches for treating cervical spine trauma with ossification of posterior longitudinal ligament]

Abstract

Objective: To investigate the clinical application value of using laminoplasty combine with short-segment pedicle screw fixation in the treatment of cervical spine trauma patients with ossification of posterior longitudinal ligament (OPLL). Methods: Fifty-four cervical spine trauma patients with OPLL from June 2014 to June 2016 were retrospectively analyzed of Department of Spine Surgery, Changzheng Hospital, Naval Military Medical University. There were 31 males and 23 females, aging (68.4±4.3) years (rang: 46 to 82 years). All patients had a history of cervical spine trauma, confirmed by imaging examination of OPLL, and there are signs and symptoms related to cervical spinal cord compression. Eighteen patients underwent one-stage laminoplasty combine with short-segment pedicle screw fixation(group A), and 15 patients underwent posterior cervical laminectomy and pedicle screw fixation (group B). Twenty-one patients underwent posterior laminoplasty (C group). According to the range of OPLL and the compression of the spinal cord, the range of laminoplasty was selected. MRI scan was used to evaluated the compression condition of cervical spine and the injury condition of anterior longitudinal ligament injury and other factors that can cause local instability of the cervical spine. Posterior unilateral pedicle screw fixation (two pedicles) were performed in the instability segment. The neurological function of the patients was assessed by the Japanese Orthopedic Association (JOA) Score before surgery, the second day after surgery, 3 months, 1 year and the last follow-up. The cervical spine X-ray films were used to evaluate cervical curvature, cervical spine activity and internal fixation-related complications. Results: The average follow-up time was 18 months (6-30 months). Satisfactory neurological improvement was achieved in all three groups, and no internal fixation-related complications occurred during follow-up. The range of laminoplasty was 22 cases in 4 segments (C(3)-C(6), C(4)-C(7)) and 17 cases in 5 segments (C(3)-C(7)). Unilateral pedicle screw fixation was performed in 11 patients with C(3-4) fixation and 7 patients with C(4-5) fixation. Cervical curvature was basically the same in the three groups after operation and at the last follow-up. No significant changes in cervical curvature and kyphosis were observed during the follow-up period. The overall cervical mobility (C(2)-C(7)) in group A and group C had no significant difference compared with preoperative (P=0.077). The overall mobility of cervical vertebrae in group B was significantly lower than that before surgery (P=0.013). Conclusions: For cervical spine trauma patients with OPLL, laminoplasty combined short-segment pedicle screw fixation can increase cervical segmental stability while extensive decompression of cervical spinal cord compression. At the same time, to some extent, the complications of postoperative axial symptoms caused by posterior cervical laminectomy and pedicle screw fixation were avoided.

Keywords: Cervical spine; Injury; Ossification of posterior longitudinal ligament; Treatment outcome.