Corpus: Ischiocavernosus muscle
1. Definition
The ischiocavernosus muscle is a skeletal muscle that forms part of the pelvic floor musculature.
2. Anatomy
2.1. Topography
The ischiocavernosus muscle is situated just below the subcutaneous tissue of the perineum, lateral to the bulbospongiosus muscle, within the superficial perineal pouch.
2.2. Origin
The muscle originates partly tendinously and partly fleshy from the inner surface of the ischial tuberosity, located behind the base of the penile crus. Additional origins are found on both sides of the crus penis, particularly on the ischial ramus and, in some cases, on the inferior pubic ramus.
2.3. Attachment
The muscle fibers run ventrally and medially, ending in an aponeurosis at the corpus cavernosum of the penis.
3. Innervation
The ischiocavernosus muscle is innervated by the perineal branches of the pudendal nerve, which originate from the sacral plexus (S2-S4).
4. Arterial supply
The arterial supply to the muscle is provided by the perineal artery.
5. Function
The ischiocavernosus muscle functions to compress the crus penis (or the corresponding structure in females, the crus clitoridis), aiding in the maintenance of erection by restricting venous outflow from the erectile tissues.