bulbospongiosus; bulbocavernosis muscle

Introduction

Perineal muscle.

Origin

Male:

• perineal membrane fascia on the dorsum of the bulb of the penis

Female:

• dorsum of the clitoris
• corpus cavernosum
• perineal membrane

Insertion

Male:

• central tendon of the perineum
• median raphe on the free surface of the bulb

Female

• central tendon of the perineum

Action

Male:

• voluntarily constricts bulbous urethra when attempting to expel last drops of urine
• spasmodically constricts with & following ejaculation to expel semen

Female:

• acts as a weak sphincter of the vagina
• when developed, is part of a cross-musculature of the pelvic floor that resists prolapse of pelvic viscera
• surrounds & compresses greater vestibular gland expressing secretion, especially during erection of the bulb of the vestibule

Innervation

deep perineal branch of the pudendal nerve

More general terms

• skeletal muscle (voluntary muscle)