The mid-urethral sling (MUS) procedure is the gold standard surgical treatment for stress urinary incontinence. What is the PRIMARY mechanism of action of the tension-free vaginal tape (TVT) retropubic sling?

• A Compresses the urethra permanently at rest to prevent urine leakage at all times
• B Recreates the pubourethral ligaments and provides a backboard for dynamic urethral kinking during increased intra-abdominal pressure ✓
• C Repositions the bladder neck above the pelvic floor, restoring normal pressure transmission
• D Enhances rhabdosphincter tone by stimulating periurethral connective tissue remodeling

Explanation

Ulmsten's integral theory: the mid-urethral sling (TVT) works by recreating the pubourethral ligaments, providing a hammock-like backboard at the mid-urethra. During stress (cough, sneeze), the pelvic floor muscles contract; the sling provides a firm posterior support against which the urethra kinks and closes, preventing urine leakage. The tape is placed tension-free at rest — it does NOT compress the urethra continuously (which would cause voiding dysfunction). Bladder neck repositioning is the older Marshall-Marchetti-Krantz mechanism, not MUS.

Reference: Shaw's Textbook of Gynaecology, 17th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.