Pelvic Floor and Perineum

Which muscle forms the main muscular component of the external anal sphincter and is innervated by the inferior rectal branch of the pudendal nerve?

A 52-year-old Indian woman presents with a 3-year history of progressive urinary incontinence on coughing, sneezing, and during exercise. She has had 3 vaginal deliveries, the last 15 years ago. On examination, there is demonstrable urine leakage with Valsalva maneuver (cough stress test positive). Urinalysis is normal. She denies urgency or nocturia. Which anatomical structure is primarily compromised in this condition?

A 48-year-old Indian man undergoes transurethral resection of the prostate (TURP) for benign prostatic hyperplasia. Intraoperatively, the surgeon inadvertently perforates the prostatic capsule during resection. Postoperatively, the patient develops severe perineal pain, scrotal edema, and cellulitis extending into the lower abdominal wall and medial thighs. Which anatomical space has been violated, and what is the route of spread of infection?

The perineal body (central tendon of the perineum) is a fibromuscular mass located at the junction of three compartments. Which of the following is NOT a muscle that attaches to the perineal body?