Most testicle lumps occur because of an injury. However, birth defects and other factors can also cause lumps in the testicles.
This type of lump is the most common, occurring in about one in every seven men. Enlarged veins in the testicles cause varicocele lumps. They become more noticeable after puberty when blood flow increases in the fully developed testicles.
A hydrocele testicular lump is caused by the buildup of fluid in the testicles. This type of testicular lump occurs in one to two out of every 100 newborn males.
An epididymal cyst or spermatocele occurs when the long, coiled tube behind the testicles (epididymis) becomes filled with sperm and cannot drain. This form of testicular lump affects up to one in three men, and most often resolves on its own.
Testicular torsion occurs when the testicles become twisted, typically due to an injury or accident. This condition most often occurs in boys between the ages of 13 and 17, but can affect men of all ages. This is a medical emergency and requires urgent investigation and possible treatment.
This is rare.
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