Undescended testicle (Cryptorchidism) – everything you need to know

What are undescended testicles (cryptorchidism)?

Testicles or testes are organs that develop during fetal life intraabdominally. Around the 28th gestational week, the testes migrate from the abdomen to the groin and into the testicular sac.
Undescended testes are a common congenital defect that manifests in such a way that causes one of the testes not to descend to its natural position in the testicular sac. Therefore, a testicle palpated outside the sac and is unable to be brought down into the scrotum by hand is referred to as undescended testicle.

What is the prevalence of undescended testicles in children?

The prevalence of undescended testicles in term babies (37 weeks or older) is about 1-2%. The prevalence in preterm babies is much higher and can reach up to 30%. It is often detected immediately after birth.
It is more common to find that one testicle is undescended and less common to find both testes undescended. Bilateral undescended testes can occur in up to 30% of all cases of undescended testes.

Are there different types of undescended testicles?

There aren’t really different types of undescended testicles but we do distinguish between testes that are palpable in the inguinal region, along their descending route and those that are not palpable at all. There is another type referred to as retractile testes, as you will see below.
Impalpable testicles – this can be due to many different reasons:
• It is possible that the testicle was stuck along the migration process and is still found in the abdomen (abdominal testicle)
• It is possible that testicle atrophied and disappeared during the pregnancy or immediately after the delivery and therefore does not exist
• Ectopic testicle – a testicle that diverted from its natural migration route and remained within the abdominal wall/the base of the femur etc.
• It is possible that the testicle is not palpable not because it does not exist but because it is hidden, for example in fat children it can be hard to palpate their testes.

In about 80% of the cases the undescended testicle was be palpable within the groin and that is how you can be certain that the testicle does exist. In about 20% of the remaining cases there is a question about whether the testicle is in the abdomen or hasn’t developed at all. This requires a diagnostic procedure that includes screening the abdomen with the help of a small camera (diagnostic laparoscopy).

What is the difference between undescended testicles and mobile testicles?

During pregnancy, the testes develop in the abdominal cavity and as the fetus approaches the end of the 7th month of pregnancy, the testes migrate to the inguinal region and fixate in the scrotum. This process is led by an anatomical structure known as the gubernaculum testis (the testicular lead), that leads the migration of the testicle and eventually anchors it in the testicular sac.
As mentioned previously, in most cases the testicle will anchor in the groin and rarely will it remain in the abdominal cavity.
An additional condition – when this process occurs as described but the muscle that connects the testicle to the abdominal muscles (cremaster muscle) has a higher contractile ability than the normal, the result will be a mobile or retractile testis. Mobile testes descend spontaneously into the scrotum (and can be pushed down manually during a physical examination) in such a way that allows it to be palpable.
Mobile testes, contrary to undescended testes are completely normal.

What needs to be done when undescended testicles are diagnosed in a baby after birth?

Some of the testes that are undescended after birth are able to complete their descend to the scrotum during the first 6 months of life. This happens in about 50% of cases of undescended testicles that are palpable in the inguinal canal, whose descend was stopped along their natural path through which they were supposed to migrate (from the abdominal cavity to the scrotum). In these situations, medical monitoring is warranted and if there is no improvement, surgical intervention for the relocation of the testes should be considered. The surgery should be planned starting at the 6th month of life, in babies who were born term.
An undescended testicles that has diverted from its natural path of migration and is located at the base of the thigh, closer to the scrotum or on the surface of the abdominal wall, will not complete its migration process within the first 6 months of life. These types of undescended testis, referred to as ectopic testis, will always require surgical intervention.
Some people with an undescended testis also present with inguinal hernias. These types of undescended testis also require surgical intervention.

Does a child with undescended testicles need to undergo any further investigations?

Undescended testicles are diagnosed clinically, which means the diagnosis can be done by a physical examination (sometimes an experienced professional is required).
A child found to have undescended testes does not need any further investigations such as ultrasound (many times these children are ordered ultrasounds but it isn’t really necessary).

When are additional investigations required?

When a testicle is impalpable, an ultrasound is required in order to try and detect the testicle (which could have been impalpable during the examination but be sitting in the inguinal region somewhere outside the natural path). If the ultrasound scan is also unable to detect the testicle, the management varies (see below).
When both testes are impalpable on physical examination and aren’t detected by ultrasound, an endocrinologist referral is warranted.

Why do undescended testes need to be treated?

There are several excellent reasons why undescended testes need to be operated on and fixated in the scrotum:
1. Testes are comparable to a factory that produces the male hormone testosterone and sperm cells. This factory requires some special conditions. The testes need to be at a lower temperature than the rest of the body and must be mobile. Both of these conditions are available in the scrotum which hangs outside the body and that is why it’s important to fixate the testis in the scrotum and not to leave it elsewhere. The chances of normal fertility in the presence of one testicle is the same as that of two. However, when both testicles are undescended, the rates of fertility are reduced.
2. It has been proven that the chance of having a malignancy is much higher in an undescended testis compared to descended testis. This topic causes concern and distress among parents of children with undescended testes. This is the place to emphasize that testicular cancer, which presents ages 15-35, is very uncommon, even if we take into consideration those cases that occur in undescended testes. Keep in mind that when the testicle is fixated in place, the risk of malignancy does not decrease, but when it is in its natural place it is much more accessible and easier to detect a cancer in it.
3. Most of the cases of undescended testes present together with inguinal hernias (some of the hernias are easily detected and diagnosed clinically by the physician while others are only detected during surgery), such that a surgery for fixation of the testis in the scrotum allows for the management of the hernia as well. You can find out more about inguinal hernias in the following link.
4. There is a higher prevalence of testicular torsion in undescended testis than there is in normal testis that are found in the scrotum. Torsion is a condition in which the testicle turns around its own axis and as a result blocks off its own blood supply – this may cause damage, ischemia and loss of the testis.
5. The testes are more protected inside the scrotum from external trauma or harm. For example: undescended testes that have not been operated on and are found in the inguinal canal, with hip bones laying behind it, will be more easily injured following a direct trauma because it can be squashed against the bone behind it as it has a hard surface. Its natural location in the scrotum protects it from this.
6. If we decide not to operate on the undescended testis, the presence of a single testis in the scrotum could have a cosmetic psychological effect on the child. This is very important because some of the children who grow up with one testis (because of loss of a testis during an accident, a congenital deficiency, atrophy etc.) are referred for prosthetic implant during adolescence.

When and how are the surgeries for testicle fixation performed?

Nowadays this surgery (referred to as orchiopexy) is done after the age of 6 months. The precise timing is up to the surgeon and is individual to the case. The surgery, which lasts about an hour, is done under general and local anesthesia and is usually done in day surgery. The child is discharged home after spending a few hours under observation.
During the surgery, the surgeon makes a small incision in the groin, detects the testis, transfers it into the scrotum and fixates it there. The fixation itself requires an additional small incision in the scrotum. Both the incision in the groin and the one in the scrotum are closed with absorbable sutures, so that they don’t need to be removed alter on.
When the undescended testis is in the abdominal cavity, the abdomen is screened laparoscopically. The surgeon inserts a small camera through the incision in order to find the exact location of the testis. If it is indeed in the abdominal cavity, the surgeon releases its blood supply and the spermal duct from the abdomen and fixate the testis in the testicular sac. When the testis is not found in the abdomen and only remnants are found, the remaining tissue is removed. There are exceptional cases when the undescended testis is found far away from the sac and the treatment needs to be done with two different surgical stages instead of one. These are exceptional situations.

What is to be expected after this surgery?

In most cases the pain that presents following surgery and after the anesthesia wears off is manageable. Obviously, analgesics are recommended such as paracetamol or ibuprofen – depending on your surgeon’s instructions. We usually recommend staying home for 5 days after the surgery. Physical exertion should be avoided (climbing, playground, tricycles) for about 3 weeks after the surgery, to allow for a full and good recovery of the area.

What are the possible complications of the surgery for correction of undescended testis?

The complications are not common. Nonetheless, here is a short list of the more common potential complications:
Infection of the surgical wound: this could present 3-4 days after surgery and usually manifests with redness and swelling of the scar. It could also present with fever. In such situations, see your surgeon for an assessment.
Usually these infections are treated with antibiotics.
Incision and drainage is sometimes needed but is less common.
Swelling and internal hematomas in the scrotum are common signs that resolve spontaneously without any treatment.

What are the chances of success and are any problems to be expected in the future?

In most cases, the surgical management of undescended testis is very successful.
Children with undescended testis that underwent correction during infancy have a rate of fertility that is almost equal to children who were born with two descended testes.
The rates of fertility are much lower in children with two undescended testes.

So what have we learnt about undescended testis?

That this condition is quite common in children. Proper detection and management by professionals in the field will again solve most issues that present with this condition.