Neurourologic findings in conus medullaris and cauda equina injury.

Fifty-seven patients with documented conus medullaris and cauda equina injury underwent neurourologic evaluation consisting of cystometrography (CMG), perineal floor electromyography (EMG), and bethanechol chloride supersensitivity testing (BST). The bulbocavernosus reflex was normal in only 16% of the patients, and perineal sensation and muscle stretch reflexes were absent or significantly diminished in 77%. The predominant CMG finding was detrusor areflexia (93%). Neuropathic EMG changes were noted in 67% and a positive BST response in 95% of the cases. Statistical analysis showed significant correlations between (1) a compromised bulbocavernosus reflex and perineal floor neuropathy (.01 less than P less than .05) and (2) sex of the patient and incidence of urinary incontinence among subjects with perineal floor neuropathy (P less than .01). The major neurourologic features in these patients (1) An absent or substantially diminished bulbocavernosus reflex, (2) detrusor areflexia on CMG, (3) neuropathic perineal EMG changes, and (4) a positive BST response.