About myelomeningocele, what type of bladder is present in about 85% of patients?

• A. Neurogenic
• B. Reflex
• C. Acontractile
• D. Overflow

Answer: (A)

When the spinal cord is disrupted in myelomeningocele, neural control of the bladder and external sphincter is lost. This produces a neurogenic bladder, the pattern most commonly seen in these patients. The lesion often leaves the reflex arc intact while removing higher-level voluntary control, so the bladder tends to contract reflexively (detrusor hyperactivity) with poor coordination to the sphincter (detrusor–sphincter dyssynergia). This neurogenic dysfunction is why about 85% of patients with myelomeningocele have a neurogenic bladder.

Overflow would imply underactive detrusor or obstruction, and an acontractile pattern implies little to no detrusor contraction—neither of these best describes the typical MMC presentation. A reflex description can be part of the neurogenic picture, but the broad and correct category for this condition is neurogenic bladder.