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.