Facet Joint- and Nuchal Ligament-Sparing Laminectomy is Not Inferior to Conventional Open-Door Laminoplasty from Clinical and Radiologic Perspectives.

Abstract

To investigate the noninferiority of facet joint- and nuchal ligament-sparing laminectomy (FNL) compared with conventional open-door laminoplasty. This retrospective study analyzed 31 patients who underwent FNL (7 women; median age, 71 years) and 29 patients who underwent laminoplasty (9 women; median age, 61 years) with cervical myelopathy due to degenerative cervical spine diseases. The surgical concept in laminectomy was to spare the facet joints and nuchal ligament, providing laminectomy with deviation to the side of dominant symptoms. In both groups, recovery rate of Japanese Orthopaedic Association (JOA) score, mean decompression ratio (decompressed width/distance between outermost edges of the lateral mass on computed tomography ×100) at decompressed laminas, and pre- and postoperative final cervical Cobb angle and cervical sagittal vertical axis were mainly examined. Clinical and radiologic median data with interquartile range for patients who underwent FNL and laminoplasty were as follows: postoperative follow-up, 783.0 days (535.0-1128.0 days) and 731.0 days (524.0-1213.5 days); preoperative JOA score (full score 17), 13.0 (9.5-15.0) and 13.0 (10.0-14.0); recovery rate of JOA score, 72.2% (33.3-100.0%) and 50.0% (31.0-75.0%); and mean decompression ratio, 41.9% (40.0-43.6%) and 51.6% (48.9-55.4%), respectively. The FNL group showed a comparable recovery rate of JOA score to the laminoplasty group, despite the significantly smaller mean decompression ratio (P < 0.001). Furthermore, no significant differences in pre- or postoperative median cervical Cobb angle or sagittal vertical axis were observed between groups. FNL was not inferior to conventional open-door laminoplasty in terms of clinical or radiologic outcomes, reducing the detachment of muscle from each lamina.