Clinical and radiological outcomes following open door laminoplasty: a single center evolution of the technique.

ABSTRACT

BACKGROUND: The aim of the present study was to compare and describe clinical and radiological outcomes after two different variants of open door laminoplasty for cervical spondylotic myelopathy (CSM). METHODS: Fifty-five patients underwent cervical laminoplasty for CSM. Between 2005 to 2009, 32 patients underwent open-door laminoplasty (Group A) performed with a monolateral exposure with contralateral "green stick" laminar fracture. A technical variant consisting in bilateral exposure, spinous process removal and symmetrical muscular closure was applied in the other 23 (Group B), from 2009 to 2016. A retrospective analysis of surgical results between the two groups was performed. RESULTS: In group B, the mean operative time was longer, and the mean volume of intraoperative blood loss was much higher than in group A. Both differences were not significant (P=0.1601 and P=0.0884, respectively). The average hospitalization was non-significantly longer in group B (7.3±1.8 vs. 6.5±1.6 d; P=0.0947). Postoperatively, axial neck pain was more severe in group A at last follow-up than preoperatively (P>0.05). mJOA scores and Nurick grades improved significantly in both groups at last follow-up; in group A, the mean recovery rates were 41.5% by mJOA scores and 29.4% by Nurick grades, whereas in group B they were 52.7% and 36.8%, respectively. CONCLUSIONS: Applying some few variations to a standard monolateral approach, although slightly more time and blood consuming, could reduce the incidence of long-term axial symptoms and, in our experience, are not burdened by worsening of outcomes. A prospective, multicentric study with a longer follow-up should be conducted in order to confirm our findings.