Introduction: Neurogenic bladder dysfunction is one of devastating sequelae of traumatic conus medullaris syndrome (T-CMS). The aim of this study was to develop a model for predicting neurogenic bladder dysfunction in a minimum of 2 years after T-CMS development.

Methods: We evaluated 39 patients who presented with acute T-CMS. T-CMS was defined with any neurological deficit (sensory change, leg weakness, or autonomic dysfunction) occurred immediately after trauma, combined with compression due to fractured fragment or epidural hematoma, or signal change of conus medullaris, which were confirmed on MRI. All patients underwent spinal surgery and were followed-up for more than 2 years. At minimum 2 years post-injury, neurogenic bladder dysfunction was scored using SCIM III (0, indwelling catheter; 3, Residual urine volume [RUV] > 100cc, no regular catheterization or assisted intermittent catheterization; 6. RUV < 100cc or intermittent self-catheterization, needs assistance for applying drainage instrument; 9, Intermittent self-catheterization, uses external drainage instrument, does not need assistance for applying; 11, Intermittent self-catheterization, continent between catheterizations, does not use external drainage instrument; 13, RUV <100cc, needs only external urine drainage, no assistance is required for drainage; 15, RUV <100cc; continent; does not use external drainage instrument). Of possible outcome predictors, we evaluated age, gender, cause of injury, American Spinal Injury Association Impairment Scale grade, time to magnetic resonance imaging, fracture level, fracture type, canal diameter, occupation ratio, signal changes in the conus medullaris (normal, edema, hemorrhage), extent of edema, time to surgery, and surgical approach. Comparison was done between patients with continent group and incontinent group. The relationships between these parameters and neurogenic bladder dysfunction were assessed via multivariate logistic analyses.

Results: At the final assessment, fifteen patients (38.5%) had 11 of SCIM III bladder dysfunction score (using catheter), three patients (7.7%) had 13 of SCIM III bladder dysfunction score (using diapers), and twenty-one patients (53.8%) had 15 of SCIM III bladder dysfunction score (continent). Between continent and incontinent groups, the presence of hematoma and the length of high signal change (extent of edema) were significantly different between groups (P<0.05). Independent risk factors for bladder dysfunction included only the length of edema in multivariate logistic analyses (adjusted odds ratio = 1. 164, 95% confidence interval = 1.020-1.330).

Discussion: Our results highlight the relatively high prevalence of bladder dysfunction in T-CMS patients in a minimum 2 year follow-up. The length of edema in conus medullaris region was associated with an increased risk for long-term neurogenic bladder dysfunction in T-CMS patients.