Cremaster muscle

The cremaster muscle is the thin fascial muscle of the spermatic cord made of skeletal muscle. It is also referred to as cremaster fascia or simply the cremaster. Its action is to retract the testes, important in thermoregulation and spermatogenesis. 

It is derived from the internal oblique muscle and aponeurosis and, as some authors report, the transversus abdominis and transversalis fascia. As the testes descends through the deep inguinal ring, inguinal canal and then the superficial inguinal ring during development, the muscle layers traversed contribute to the fascial sheet which retains muscular fibres. The transversus muscles fibres spiral along the cord and some return up to attach to the pubic tubercle. A larger component originates from the internal oblique fibres, some of which also return to the pubic tubercle.

Its blood supply is from the cremasteric artery, a branch of the inferior epigastric artery.

The cremaster is innervated by sympathetic and somatic fibres of the genital branch of the genitofemoral nerve

Cremaster reflex

The cremaster reflex is elicited by gently stroking the skin of the medial upper thigh which causes ipsilateral contraction of the cremaster muscle and retraction of the testes. The sensory nerve stimulated is the ilio-inguinal nerve and the motor nerve is the genital branch of the genitofemoral nerve. It is more pronounced in neonates and children and may even retract the testes into the spermatic cord. When exaggerated, it can simulate cryptorchidism.

Abdominal and pelvic anatomy
Share article

Article information

rID: 51944
System: Urogenital
Section: Anatomy
Synonyms or Alternate Spellings:
  • Cremaster fascia

Support Radiopaedia and see fewer ads

Updating… Please wait.
Loadinganimation

Alert accept

Error Unable to process the form. Check for errors and try again.

Alert accept Thank you for updating your details.