What causes the testicle to shrink into the inguinal groove?

The testicle is an especially important reproductive organ for men. Normally, it can be touched by hand. However, due to some physical and endocrine reasons, the testicle shrinks to the inguinal groove and can no longer be touched by hand. This symptom is divided into four categories: cryptorchidism, inguinal testicle, mobile testicle, and lost testicle. During the treatment process, patients need to deal with it according to their actual situation.

1. Physical reasons:

1. The frenulum of the testis has the traction effect on the testicular muscle.

2. Intra-abdominal pressure pushes the testicles down into the scrotum.

3. Normal epididymal development is also a factor in testicular descent.

2. Endocrine reasons:

1. The secretory axis that affects the descent of the testicle, namely the hypothalamus-pituitary-testis axis, is abnormal, resulting in cryptorchidism.

2. Müllerian inhibitory substance (MIS) secreted by testicular support cells and male hormones testosterone and dihydrotestosterone also affect testicular descent.

3. Suffering from Kallmann syndrome, lack of hypothalamic gonadotropin-releasing hormone leads to cryptorchidism.

4. Patients with 5D-dehydrogenase deficiency cannot effectively convert testosterone into dihydrotestosterone, which is enough to affect the descent of the testicles and produce cryptorchidism.

3. Abnormal testicular descent is divided into four types:

Statistics show that the proportion of full-term infants with undescended testicles is 2.7%, which drops to 0.77% when the infants reach full age. Generally speaking, premature infants have the highest rate of occult testis, up to about 20%. Some experts believe that this may be due to the fact that premature infants themselves are not fully developed.

(I) Cryptorchidism: The testicles are located in the abdominal cavity or at the posterior side of the abdominal cavity and cannot be seen or felt. This condition accounts for 5-20% of abnormal testicular descent.

(B) Inguinal testicles: The testicles are located in the inguinal groove.

(III) Migrant testicles: The testicles wander outside the inguinal groove and scrotum. This type of positional abnormality means that the testicles are originally in the scrotum, but when stimulated, they shrink upwards and move to the inguinal groove. Or the testicles outside the inguinal groove can be squeezed down to the scrotum by hand. This is the most common testicular descent abnormality and is less likely to cause infertility problems.

(IV) Lost testicles: The testicles have no idea where they are going and are not on their descending path. This accounts for about 5% of abnormal testicular descent.