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The scrotal ligament is actually the remnant of gubernaculum in a fetus. This ligament secures the testis to the most inferior portion of the scrotum, tethering it in place and limiting the degree to which the testis can move within the scrotum. The Scrotum The scrotum develops from an out-pouching of the skin of the anterior abdominal wall. The scrotum is a loose cutaneous fibromuscular sac that is situated posteroinferior to the penis and inferior to the pubic symphysis. Its bilateral formation is indicated by the midline scrotal raphe. This continues on the ventral surface of the penis as the penile raphe and posteriorly along the median line of the perineum to the anus as the perineal raphe. The scrotum is composed of skin and dartos muscle. The dartos muscle is firmly attached to the skin and consists largely of smooth muscle fibres that contract under the influence of cold, exercise, and sexual stimulation. Under these conditions the wall of the scrotum becomes contracted and firm. Its skin becomes rugose. Contraction of the dartos and cremasteric muscles causes the testes to be drawn up against the body. In hot weather the scrotum relaxes and allows the testes to hang freely away from the body. This provides a larger skin surface for the dissipation of heat. These reflexes of the scrotum in response to temperature help to maintain a stable temperature, an important function because spermatogenesis is impaired by extremes of heat or cold. In older men the dartos muscle loses its tone and the scrotum tends to be smoother and to hang down further. 〔(Male Genatalia )〕 Arterial Supply of the Scrotum The external pudendal arteries supply the anterior aspect of the scrotum. The internal pudendal arteries supply its posterior aspect. It also receives branches from the testicular and cremasteric arteries. Venous Drainage of the Scrotum The scrotal veins accompany the arteries and join the external pudendal veins. Innervation of the Scrotum Its anterior part is supplied by the ilioinguinal nerve. Its posterior part is supplied by the medial and lateral scrotal branches of the perineal nerve and the perineal branch of the posterior femoral cutaneous nerve. Lymphatic Drainage of the Scrotum The lymph vessels from the scrotum drain into the superficial inguinal lymph nodes. ==References== 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Scrotal ligament」の詳細全文を読む スポンサード リンク
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