Risk factors for poor outcome of cervical laminoplasty for cervical spondylotic myelopathy in patients with diabetes.

BACKGROUND Diabetes is one of the most frequent comorbidities in patients with cervical spondylotic myelopathy. The purpose of this study was to characterize the risk factors for poor treatment outcome following cervical laminoplasty for cervical spondylotic myelopathy in patients with diabetes. METHODS A total of 105 consecutive patients with diabetes and cervical spondylotic myelopathy who underwent double-door laminoplasty were included in this study; there were sixty-five male patients and forty female patients with a mean age of 68.2 years (range, forty-three to eighty-three years). All patients were followed for twelve months or more after surgery, with a mean follow-up time (and standard deviation) of 25.7 ± 14.2 months. All patients had palliative controlled blood glucose levels in the immediate term during the perioperative period. We evaluated the recovery rate on the basis of the Japanese Orthopaedic Association score. Logistic regression analyses (univariate analysis and multivariate analysis) were performed to identify the risk factors for poor outcome. Poor outcome was defined as a postoperative recovery rate of <50%, and good outcome was defined as a postoperative recovery rate of ≥ 50%. RESULTS Univariate logistic regression analysis showed that a patient age of sixty-five years or older (odds ratio, 3.111; p = 0.0085) and a duration of cervical spondylotic myelopathy symptoms for twelve months or more (odds ratio, 3.940; p = 0.0012) were associated with an increased risk of poor surgical outcome. High glycated hemoglobin levels of ≥ 6.5% (odds ratio, 2.591; p = 0.0193) and a duration of diabetes for ten years or more (odds ratio, 2.245; p = 0.0321) were significant risk factors for poor surgical outcome. Multivariate logistic regression analysis determined that glycated hemoglobin levels of ≥ 6.5% (odds ratio, 2.822; p = 0.0441) and a duration of diabetes for ten years or more (odds ratio, 2.240; p = 0.0410) were significant risk factors for poor treatment outcome. Fasting blood glucose levels did not affect treatment outcomes. CONCLUSIONS Diabetes with advanced age and long-term cervical spondylotic myelopathy symptoms adversely affected cervical laminoplasty outcomes. High preoperative glycated hemoglobin levels and long-term diabetes are risk factors for poor cervical laminoplasty outcomes in patients with diabetes and cervical spondylotic myelopathy.