Spina bifida with lesion at L1 or lower typically presents with which bladder type?

• A. Spastic bladder
• B. Flaccid bladder with dribbling
• C. Overflow incontinence with high bladder pressure
• D. Normal bladder function

Answer: (B)

The key idea is that bladder behavior depends on where the spinal lesion disrupts neural control of the bladder. When the lesion is at or below the sacral level (as with spina bifida affecting L1 or lower), the detrusor muscle and coordinated micturition reflex are lost or diminished. This produces a flaccid (areflexic) detrusor that can’t contract effectively to empty the bladder, leading to urinary retention and overflow leakage with dribbling. In contrast, lesions above the sacral center cause a spastic bladder with detrusor overactivity and high-pressure filling, which isn’t typical for L1 or lower. Normal bladder function isn’t seen with these lesions. Therefore, a bladder that is flaccid with dribbling fits the pattern of a lower-level spinal lesion like L1 or lower.