Predictors of Outcome in Patients with Cervical Spondylotic Myelopathy Undergoing Unilateral Open-Door Laminoplasty

Abstract

ObjectiveThis study aimed to analyze prognostic factors affecting surgical outcomes of expansive laminoplasty for cervical spondylotic myelopathy (CSM).MethodsUsing the Frankel scale and Japanese Orthopaedic Association (JOA) scale, we retrospectively reviewed the outcomes of 45 consecutive patients who underwent modified unilateral open-door laminoplasty using hydroxyapatite spacers and malleable titanium miniplates between June 2008 and May 2014. The patients were assigned to the good and poor clinical outcome groups, with good outcome defined as a JOA recovery rate >75%.ResultsThe mean preoperative JOA scale was significantly higher in the good outcome group (14.95±3.21 vs. 10.78±6.07, p<0.001), whereas the preoperative cervical range of motion (ROM) in this group was significantly lower (29.89°±10.11 vs. 44.35°± 8.88, p<0.001). In univariate analysis, a high preoperative JOA scale (odds ratio (OR) 1.271, 95% confidence interval (CI) 1.005-1.607) and low preoperative cervical ROM(OR 0.858, 95% CI 0.786-0.936) were statistically correlated with good outcomes. Furthermore, these factors demonstrated an independent association with clinical outcomes (preoperative JOA scale: OR 1.344, 95% CI 1.019-1.774, p=0.036; preoperative cervical ROM: OR 0.860, 95% CI 0.788-0.940, p=0.001).ConclusionIn this study, a high preoperative JOA scale was associated with good clinical outcome after laminoplasty, whereas a higher preoperative cervical spine ROM was associated with poor clinical outcome. This may suggests that cervical mobility and preoperative neurological status affect clinical outcomes of laminoplasty.

Cervical Spondylotic Myelopathy: Pathophysiology and Surgical Approaches

“…Several studies showed that laminoplasty reduced cervical ROM in various degrees [34,35,[37][38][39][40]. As shown in Table 2, it seems that the preservation of C2 and C7 muscle attachments have an important role in the preservation of cervical ROM postoperatively.…”

“…Most of these studies used the JOA score as a parameter of clinical outcome. They reported that laminoplasty provided significant enhancement of the JOA score in the short-term, mid-term, and long-term follow-up [34][35][36][37][38][39]. However, Sakaura et al [40] reported that the average JOA score was at its highest point in 12 months of follow-up and decreased slightly to 14.9 in the final follow-up.…”

“…Similarly, Heller et al [42] reported that both laminoplasty approaches exhibited similar good clinical outcomes. Furthermore, the recovery rate (RR) of laminoplasty was greater than 50% in the short-term, mid-term, and long-term follow-up [35,[38][39][40][41]. On the other hand, Uehara et al [34] reported that RR was 47.1% in the final follow-up, but 55.9% immediately after operation.…”

“…Interestingly, Shin et al [35] used the Frankel score to measure the clinical outcome of laminoplasty and found an improvement in the Frankel score from 3.93 to 4.53 at 12 months post operation. However, the difference was not significant.…”

“…Several studies reported that laminoplasty reduced the C2-C7 lordotic angle [34][35][36][37]. These studies used different laminoplasty methods to provide decompression of the spinal cord.…”