Anatomic basis of chronic groin pain with special reference to sports hernia.

Chronic pain on the ventral surface of the scrotum and the proximal ventro-medial surface of the thigh especially in athletes has been diagnosed in various ways; recently, in Europe the concept of "sports hernia" has been advocated. However, since few reports discuss the detailed course of the nerves in association with the pain, we examined the cutaneous branches in the inguinal region in 54 halves of 27 adult male cadavers. From our results, in addition to the cutaneous branches from the ilioinguinal n. (in 49 of 54: 90.7%), cutaneous branches originating from the genital branches of the genitofemoral nerve were found in the inguinal region in 19 of 54 halves (35.2%). In 7 cases (in 7 of 54: 13.0%) the genital branch and the ilioinguinal nerve united in the inguinal canal. In 6 cases the genital branch pierced the inguinal lig. to enter the inguinal canal, and in three cases the genital branch pierced the border between the ligament and the aponeurosis of the obliquus externus m. to be distributed to the inguinal region. Therefore, the courses of the genital branches vary considerably, and may have a very important role in chronic groin pain produced by groin hernia. In addition, entrapment by the ligament may be a reasonable candidate for the cause of chronic groin pain.