Overactive bladder in cervical spondylotic myelopathy

Overactive bladder (OAB) is a new disease concept defined by the International Continence Society in 2002. There have been no reports of OAB among patients with cervical spondylotic myelopathy assessed on the basis of symptom questionnaires. One-hundred-and-six patients diagnosed with cervical spondylotic myelopathy and treated by use of laminoplasty were examined. The patients were classified into two groups, those identified as having OAB (OAB group) and those identified as not having OAB (non-OAB group), by use of the Overactive Bladder Symptom Score collected before and 1 year after surgery. The clinical results for the two groups were assessed. OAB symptom prevalence and post-operative symptom improvement were investigated 1 year postoperatively. Of the 106 patients, 50 were identified as having OAB (symptom prevalence 47.2 %). Of these 50 patients, symptom improvement was observed for only 14 (28 %) 1 year after surgery. For both groups good improvement on the basis of the Japanese Orthopedic Association score was observed 1 year postoperatively, but there were no significant differences between them. Post-operative improvement of OAB symptoms in cervical spondylotic myelopathy patients was low, which indicated that OAB was most frequently attributable to non-neurogenic and idiopathic, but not neurogenic, causes. It is considered necessary to tell patients with cervical spondylotic myelopathy that the possibility of post-operative OAB symptom improvement is not high when the explanation for informed consent is given before the operation.