Longitudinal spinous-splitting laminoplasty with coral bone for the treatment of cervical adjacent segment degenerative disease: A 5-year follow-up study

Abstract

Background: To analyze the causes of cervical adjacent segment degenerative disease (ASDis), explore the surgical results of longitudinal spinous-splitting laminoplasty with coral bone (SLAC) during cervical reoperation, and accumulate data on reoperation with SLAC in a primary hospital.Methods: We conducted a retrospective study. From 1998 to 2014, 52 patients underwent cervical reoperation for ASDis using SLAC at our hospital. Among them, 39 were treated with anterior cervical fusion and internal fixation in the first operation (anterior cervical corpectomy with fusion [ACCF], n=24; anterior cervical discectomy and fusion [ACDF], n=11; and cervical disc arthroplasty [CDA], n=4).Results: In patients who underwent an anterior cervical approach in the first instance, ASDis was significantly higher in the C3/4 gap than in other gaps. In the ACCF group, the lateral radiograph of the cervical spine revealed that the distance between the anterior cervical plate and adjacent segment disc in15 cases (62.5%) was <5 mm, and five cases (12.8%) had internal fixation screws that broke into the annulus of the adjacent segment. After the first SLAC, ASDis occurred in C2/3 and C3/4 in four (30.8%) and eight cases (61.5%), respectively. Post-reoperation, all cases were follow-up for >5 (average, 6.2) years. Comparing pre-reoperation and last follow-up values, the mean Japanese Orthopedic Association score was 10.2±1.5 versus15.5±0.7 (P=0.03), neck disability index was 26.2 versus13.6 points (P=0.01), upper-limb visual analog scale (VAS) score was 6.1 versus2.6 points (P=0.04), and neck and shoulder VAS score was 6.6 versus 2.1 points (P=0.03).Conclusions: ASDis was primarily caused by 1) a distance of <5 mm between the anterior cervical plate and adjacent segment disc and 2) the screw breaking through the adjacent segmental annulus. SLAC proved to be a simple technique, with clear local anatomy and satisfactory clinical results.