[The relationship between level of injury and bladder behavior in patients with post-traumatic spinal cord injury]

After the spinal shock period, suprasacral injuries classically result in detrusor hyperreflexia/overactive bladder and detrusor sphincter dyssynergia. Sacral cord injuries produce detrusor areflexia consistent with lower motor neuron injury and often increased bladder compliance. However, previous investigators have noted an inexact correlation between spinal cord injury level and urodynamic findings. The aim of this study was to evaluate the relationship between level of injury and urodynamic findings.

Fifty-one patients with post-traumatic spinal cord injury were classified by the radiographically determined level of injury, clinical neurologic level and completeness of injury. Urodynamic studies were performed in all patients.

Twenty-six of 36 patients with suprasacral injuries had hyperreflexia/overactive bladder (72.2%). Twenty-nine (80.5%) had detrusor sphincter dyssynergia, 9 (25%) had normal compliance and 1 (2.8%) had areflexia. Six of the 14 patients with sacral injuries had areflexia (42.8%), 2 (14.3%) had hyperreflexia/overactive bladder, 2 (14.3%) had detrusor sphincter dyssynergia, and 6 (42.8%) had normal compliance.

The correlation between somatic neurologic findings or spinal imaging studies and urodynamic findings in patients with spinal cord injury is not exact. These data suggest that the neurologic examination alone is not an adequate parameter to predict urological dysfunction and that urodynamic evaluation provides a more precise diagnosis for each patient.