SCROTUM AND TESTIS

SCROTUM AND TESTIS

Definition

The scrotum is a sac like structure that contains the testis, epididymis, vas deferens, and spermatic cord. It is a muscular, fibrous, and cutaneous pouch that hangs from the base of the penis.

Boundaries

The scrotum is bounded by the following structures:

• Anteriorly: The scrotum is bounded by the penis.
• Posteriorly: The scrotum is bounded by the perineum.
• Laterally: The scrotum is bounded by the thigh.
• Medially: The scrotum is bounded by the pubis.

Layers

The scrotum is composed of the following layers:

• Cutaneous layer: The outermost layer of the scrotum is composed of skin and subcutaneous tissue.
• Superficial fascia: Beneath the cutaneous layer lies the superficial fascia.
• Dartos muscle: The dartos muscle is a smooth muscle layer that lies beneath the superficial fascia.
• Cremaster muscle: The cremaster muscle is a smooth muscle layer that lies beneath the dartos muscle.
• Visceral layer: The visceral layer is composed of peritoneum and lies beneath the cremaster muscle.

Contents

The scrotum contains the following structures:

• Testis: The testis is a male reproductive organ that produces sperm and hormones.
• Epididymis: The epididymis is a long, coiled tube that stores and matures sperm.
• Vas deferens: The vas deferens is a muscular tube that transports sperm from the epididymis to the urethra.
• Spermatic cord: The spermatic cord is a bundle of blood vessels, nerves, and lymphatic vessels that supply the testis.

Development

The scrotum develops from the following structures:

• Development of the gonad: The gonad develops into the testis.
• Descent of the testis: The testis descends through the inguinal canal into the scrotum.
• Formation of the scrotum: The scrotum forms from the skin and subcutaneous tissue of the inguinal canal.

Nerve Supply

The scrotum is supplied by the following nerves:

• Genital branch of the genitofemoral nerve: The genital branch of the genitofemoral nerve supplies the cremaster muscle and the skin of the scrotum.
• Ilioinguinal nerve: The ilioinguinal nerve supplies the skin of the scrotum.

Blood Supply

The scrotum is supplied by the following arteries:

• Superficial external pudendal artery: The superficial external pudendal artery supplies the skin of the scrotum.
• Deep external pudendal artery: The deep external pudendal artery supplies the cremaster muscle and the dartos muscle.

Lymph Drainage

The scrotum drains lymph to the following nodes:

• Superficial inguinal lymph nodes: The superficial inguinal lymph nodes receive lymph from the scrotum.

Muscle Action Sequence

The following muscle action sequence occurs in the scrotum:

• Contraction of the cremaster muscle: The cremaster muscle contracts to elevate the testis.
• Contraction of the dartos muscle: The dartos muscle contracts to constrict the scrotum.

Function

The scrotum functions to:

• Regulate testicular temperature: The scrotum regulates the temperature of the testis.
• Protect the testis: The scrotum protects the testis from injury.

Clinical Significance

The scrotum is clinically significant in:

• Testicular torsion: Testicular torsion occurs when the spermatic cord becomes twisted, cutting off blood supply to the testis.
• Varicocele: Varicocele occurs when the veins of the spermatic cord become dilated.
• Hydrocele: Hydrocele occurs when fluid accumulates in the scrotum.

Describe the morphology of scrotum

• The scrotum is a thin, membranous sac that contains the testis.
• It is located below the penis and is composed of two layers: the external skin layer and the internal dartos muscle layer.
• The dartos muscle layer is composed of smooth muscle fibers that contract and relax to change the temperature of the scrotum.
• The scrotum has a cremasteric reflex, which is a reflex that causes the scrotum to rise when the testis is manipulated.

Mention its blood and nerve supply

• The blood supply to the scrotum comes from the internal iliac artery via the scrotal branches.
• The nerve supply to the scrotum comes from the ilioinguinal nerve and the genital branch of the genitofemoral nerve.

Describe the morphology of testis

• The testis is an oval-shaped gland that is located in the scrotum.
• It is composed of two main parts: the epididymis and the testicular parenchyma.
• The epididymis is a narrow tube that connects to the vas deferens and stores sperm.
• The testicular parenchyma is the main part of the testis and is responsible for producing sperm.

Describe the applied anatomy of testis

• The testis is covered by a tunica albuginea, which is a tough layer of connective tissue.
• The testis is divided into lobules, which are groups of seminiferous tubules.
• The seminiferous tubules are where sperm are produced.
• The testis is connected to the epididymis via the efferent ductules.