Neurourologic findings in patients with traumatic thoracolumbar vertebra junction lesions

Objective: To investigate neurourologic involvement in injuries to the thoracolumbar vertebra junction with magnetic resonance imaging (MRI) and electrophysiologic and urodynamic measurements and to characterize the neurogenic mechanisms of voiding dysfunctions. Design: Baseline comparisons among 3 anatomic groups before neural repair. Setting: Tertiary care center. Patients: Thirty-five T11 to L2 spinal cord injury patients consecutively admitted to a rehabilitation unit. Eight patients (Group 1) had above-conus lesions without denervation and polyphasic waves revealed in the anal sphincter electromyography; 13 patients (Group 2) had conal and/or above-conus lesions and anal sphincter electromyographic abnormalities; and 14 patients (Group 3) had below-conus lesions and anal sphincter electromyographic abnormalities. Main Outcome Measures: Comparison of features identified on pudendal nerve terminal motor latency, urethral pressure profiles, and multichannel voiding pressure-flow study. Results: The pudendal nerve terminal motor latency in Group 3, showing a significantly higher abnormal ratio (100%; p = .011, Fisher's exact test), indicated that cauda equina lesions might be the cause, Urodynamic data from Group 3 showed a significant decrease in maximal urethral closure pressure (48 +/- 17cmH(2)O, p = .0022, analysis of variance [ANOVA], repeated measure) and an increase in bladder capacity (429 +/- 194mL, p = .037, ANOVA, repeated measure). There were no significant changes in the other groups. Conclusion: Neurourologic abnormalities are less predictable with injuries to thoracolumbar junction, except in patients with cauda equina lesions.