The scrotum is a pouch of skin and muscle located underneath the penis and behind the testicles in male mammals, including humans. Its primary function is to house and protect the testicles, which are responsible for producing sperm and the hormone testosterone.

What is scrotum?

The scrotum is a part of the male reproductive system, consisting of a pouch of skin and muscle located beneath the penis and behind the testicles. Its primary function is to house and protect the testicles, which are responsible for sperm production and testosterone secretion. The scrotum helps regulate the temperature of the testicles to ensure optimal conditions for sperm production, as sperm are most efficiently produced at temperatures slightly lower than the body’s core temperature. The scrotum is sensitive to temperature changes, contracting or relaxing accordingly to maintain the appropriate temperature. It also plays a role in sexual pleasure and is an essential component of the male genitalia.

Functions

The scrotum serves several important functions within the male reproductive system:

• Protection: One of the primary functions of the scrotum is to provide protection for the testicles. By enclosing the testes in a pouch of skin and muscle, the scrotum helps shield them from physical damage and injury.
• Temperature regulation: The scrotum plays a crucial role in regulating the temperature of the testicles. Sperm production (spermatogenesis) occurs most efficiently at temperatures slightly lower than the body’s core temperature. The scrotum adjusts its position in response to external temperature changes, contracting or relaxing to bring the testicles closer to or farther away from the body to maintain an optimal temperature for sperm production.
• Sperm production: Inside the testicles, sperm are produced in structures called seminiferous tubules. The lower temperature maintained by the scrotum is essential for the proper functioning of these tubules and the production of healthy sperm.
• Sexual arousal: The scrotum is sensitive to touch and temperature changes, and stimulation of the scrotal skin can contribute to sexual arousal and pleasure.
• Hormonal regulation: The scrotum is involved in the production and regulation of the male sex hormone testosterone, which is essential for the development of male reproductive tissues and secondary sexual characteristics.

Anatomy

The scrotum is an anatomical structure located between the base of the penis and the anus in males. It is composed of several layers of tissue and has a unique anatomy designed to support its functions:

• Skin: The outermost layer of the scrotum consists of skin, which is typically darker in color and may have hair follicles. The skin of the scrotum is relatively thin and elastic, allowing for changes in size and shape.
• Dartos muscle: Beneath the skin, there is a layer of smooth muscle known as the dartos muscle. This muscle is responsible for the wrinkled appearance of the scrotal skin and helps regulate the temperature of the testicles by contracting or relaxing in response to changes in temperature.
• Scrotal septum: The scrotum is divided into two compartments by a fibrous partition called the scrotal septum. This septum helps provide structural support and prevents excessive movement of the testicles within the scrotum.
• Testicles (testes): The testicles are the primary organs housed within the scrotum. They are responsible for producing sperm and the male sex hormone testosterone. Each testicle is enclosed in a protective covering called the tunica vaginalis and is suspended within the scrotum by the spermatic cord.
• Spermatic cord: The spermatic cord contains blood vessels, nerves, and the vas deferens (ductus deferens), which carries sperm from the testicles to the urethra during ejaculation. It also contains the cremaster muscle, which helps regulate the position of the testicles within the scrotum.
• Pampiniform plexus: This is a network of veins that surrounds the spermatic cord within the scrotum. It helps regulate the temperature of the testicles by cooling arterial blood before it reaches the testes.

Contents of the scrotum

The scrotum primarily contains the following anatomical structures:

• Testicles (Testes): These are the male reproductive organs responsible for producing sperm and the hormone testosterone. Each testicle is housed within the scrotum and is surrounded by protective layers of tissue.
• Epididymides: Attached to the back of each testicle is a coiled tube called the epididymis. The epididymis stores sperm and allows for their maturation and transportation from the testes to the vas deferens.
• Vas Deferens (Ductus Deferens): The vas deferens is a muscular tube that carries sperm from the epididymis to the urethra during ejaculation. It is part of the spermatic cord, which extends from the testicles into the pelvic cavity.
• Blood vessels: The scrotum contains a network of blood vessels that supply oxygen and nutrients to the testicles and surrounding tissues. The pampiniform plexus, a complex network of veins, helps regulate the temperature of the testicles by cooling arterial blood.
• Lymphatic vessels and nerves: Lymphatic vessels drain excess fluid from the scrotum and surrounding tissues, while nerves provide sensation and control over muscle function within the scrotum.
• Muscles: The scrotum contains several layers of smooth muscle, including the dartos muscle and the cremaster muscle. These muscles help regulate the temperature of the testicles by adjusting the position of the scrotum in response to changes in temperature.

Scrotal disorders

The scrotum, like any other part of the body, can be subject to various disorders and conditions. Some common disorders of the scrotum include:

• Testicular torsion: This is a medical emergency where the spermatic cord becomes twisted, cutting off blood flow to the testicle. It causes sudden and severe pain in the scrotum and requires immediate medical attention to prevent permanent damage to the testicle.
• Hydrocele: A hydrocele is a fluid-filled sac around the testicle, leading to swelling in the scrotum. It can develop due to injury, infection, or fluid accumulation within the tunica vaginalis (the membrane that surrounds the testicle).
• Varicocele: Varicocele is the enlargement of the veins within the scrotum. It can cause discomfort or pain and may affect sperm production, leading to male infertility in some cases.
• Orchitis: Orchitis is inflammation of one or both testicles, often caused by a bacterial or viral infection. It can result in pain, swelling, and fever.
• Epididymitis: This is inflammation of the epididymis, usually caused by a bacterial infection. It can cause pain and swelling in the scrotum, as well as fever and urinary symptoms.
• Scrotal trauma: Injuries to the scrotum, such as blows, falls, or accidents, can cause bruising, swelling, and pain. Severe trauma may lead to testicular rupture or hematoma (collection of blood outside blood vessels).
• Scrotal dermatitis: Dermatitis, or inflammation of the skin, can occur in the scrotum due to allergic reactions, infections, or irritants. It may cause itching, redness, and scaling of the skin.
• Testicular cancer: Although relatively rare, testicular cancer can develop in one or both testicles. It may present as a painless lump or swelling in the scrotum and requires prompt medical evaluation and treatment.

It’s essential for individuals experiencing any abnormalities or discomfort in the scrotum to seek medical attention for proper diagnosis and management. Many scrotal disorders can be effectively treated with medication, lifestyle modifications, or surgical interventions, especially when diagnosed early.

Prof.Dr. Emin ÖZBEK

Urologist

Istanbul- TURKIYE