The testicles - anatomy, functions and diseases

The testicles are part of the male sex organs and produce sperm and the male sex hormone testosterone. They are also known as the male gonads.

What are the testicles?

The testicles (testis) are a paired male sex organ. It is the counterpart to the ovaries in women and belongs to the gonads. The testicles produce sperm (semen) and hormones, which are regulated by the pituitary gland and the hypothalamus. It is also an indispensable component of sexual reproduction.

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What is the function of the testicles?

An important function of the testicles is the production of hormones (androgens) and sperm, which are used for reproduction.

Hormone synthesis is carried out by the Leydig cells. They mainly produce testosterone. The hormone testosterone plays an important role in the stimulation of sperm formation. They are also involved in the development and function of the other sex organs.

The Sertoli cells are largely responsible for sperm development and promote it. They form a supporting cell framework in which the germ cells mature.

The epididymis fulfills the function of a sperm reservoir. They also support the sperm as they mature.

During puberty, up to 200 million sperm are produced every day. Each sperm takes about two months to mature. Hormones are responsible for controlling this process. During ejaculation , semen and seminal fluid mix. This occurs in the prostate and seminal vesicles before ejaculation.

Anatomy of the testicles

The testicles are free-hanging on the spermatic cord in thescrotum. They have an elongated shape and are around three centimetres in diameter. Their length is about four centimeters and their weight varies between 25 and 30 grams. The head of the epididymis is located at the upper end of both testicles.

The testicles vary in size from man to man. From puberty, the size increases and reaches its maximum between the ages of 30 and 40. From the age of 50, the size of the testicles decreases slightly.

Components of the testicles

The testicles are surrounded by connective tissue(tunica albuginea). Inside, it is divided into more than 200 to 300 lobules. These are separated from each other by walls. Another component of the testicle is the testicular network, which is made up of several ducts that branch out and are located in the testicular lobules. The Sertoli supporting cells, which are the precursors of sperm, are located within the seminiferous tubules.

The cells located between the seminiferous tubules are called Leydig intermediate cells. Their task is to produce the male sex hormone testosterone.

The testicles are supplied with blood by the testicular artery, which is a branch of the abdominal aorta. The venous blood is collected in the plexus pampiniformis, a plexus of veins, on both sides.

The epididymis

The epididymis is located on the posterior side of the testicle. The epididymis is tightly fused with the testicle. It has a diameter of 5 to 10 millimetres and a length of 5 centimetres. It is surrounded by a thin capsule. It takes the position of a kind of cap over the testicle. There is a connection to the urethra through theductus deferens, which is located in the prostate. In this way, the sperm that are produced in the testicles are transported out of the man's body during ejaculation. The vas deferens reaches a length of 30 to 40 centimeters.

What are the most common diseases of the testicles?

There are various diseases of the testicles that should be taken seriously because they can affect a man's fertility. Sometimes they cause irreversible damage. Men between the ages of 20 and 40 are particularly affected by these diseases.

Testicular torsion

One of the most common testicular conditions is testicular torsion, which is a twisting of the testicle. The injury is usually caused by violence such as kicks to the testicles. In some people, however, testicular torsion is also congenital. In the case of testicular torsion, the testicular stalk becomes wrapped around the epididymis, which in turn leads to an interruption of the blood supply.

Since testicular torsion is a medical emergency, immediate surgical treatment is required.

Testicular inflammation

Testicular inflammation (orchitis) is relatively common. It is caused by injuries to the scrotum through which bacteria can get inside. Infectious diseases are another possible cause.

In the case of orchitis, the testicles become swollen and painful. It is not uncommon for the scrotum to become red. For treatment, the testicle is cooled and elevated. The patient is also given a suitable antibiotic.

Epididymitis

Another clinical picture is epididymitis (inflammation of the epididymis). In this case, one epididymis is usually affected by an infection.

The inflammation of the epididymis often first manifests itself as a burning sensation when urinating. Later, redness, swelling and severe pain in the genital region may occur. The clinical picture can be accompanied by fever, chills and general flu symptoms.

In most cases, epididymitis is treated by anaesthetizing the spermatic cord and administering antibiotics for several weeks. If the infection does not heal in time, there is a risk that the epididymis will have to be surgically removed.

In 15 - 20 percent of cases, the condition can also develop into a chronic variant.

Undescended testicles

Undescended testicles are a relatively common abnormal development. The testicles of male fetuses are formed in the abdominal cavity. From there, they usually migrate down into the scrotum before birth, but sometimes also afterwards.

The term undescended testicles is used when both or a single testicle has not fully migrated into the scrotum. A distinction is made between abdominal testicles, inguinal testicles, gliding testicles and pendulum testicles, whereby the latter are probably of no significance for an increased susceptibility to disease.

Around 2 to 4 percent of all newborn males suffer from undescended testicles at birth. If the testicles are not fully descended into the scrotum after the first year of life, surgery is unavoidable. Undescended testicles later lead to an increased risk of carcinomas (cancerous tumors) of the testicles (testicular cancer).

Testicular cancer

Testicular cancer is one of the most common forms of cancer in young men. Risk factors such as undescended testicles promote this disease. The cancer usually manifests itself as a painless hardening.

Testicular cancer is considered to be easily treatable. The cure rate at an early stage is 98 to 100 percent. As part of the treatment, the testicles are removed from one side(orchiectomy). Chemotherapy, radiotherapy or watchful waiting are also possible.

Hydrocele

A hydrocele is the accumulation of serous fluid in the testicles. It occurs unilaterally or on both sides and leads to a usually painless swelling of the scrotum. Possible triggers are

• predisposition
• tumors
• inflammations
• injuries

If the hydrocele has a disturbing effect, it can be surgically removed.

Varicocele

A varicocele, also known as a varicose vein, forms when the testicular vessels dilate. It becomes noticeable through tortuous vessels. However, pain rarely occurs. However, it can sometimes lead to infertility. Treatment involves sclerotherapy or surgical removal.

Diagnosis of testicular diseases

One of the most important methods used in urology to diagnose testicular disease is palpation of the organ. The doctor checks the position, size and consistency of the testicles. Imaging procedures are also used, such as sonography (ultrasound examination).

In order to determine the testicular volume, an ultrasound measurement or a comparison with the Prader chain is carried out. In some cases, a testicular biopsy is also carried out, during which some tissue is removed.

Specialists for testicular diseases

Patients with initial symptoms can consult their family doctor. If there are further questions, e.g. if the suspicion of a disease of the genital region is confirmed, the doctor will usually refer the patient to a specialist.

Urologists specialize in the treatment of urinary tract and sexually transmitted diseases. They diagnose conditions relating to the penis, testicles, prostate or urinary tract and associated organs such as the bladder.

Men over the age of 25 in particular should undergo a general urological examination every year in order to detect malignant diseases in good time, prevent risks and possibly take initial preventive measures.

Conclusion on the testicles

The testicles are extremely important for male fertility. In the event of injuries or diseases of the reproductive organ, prompt medical treatment is therefore necessary.