Because the testes are located within the scrotum, which hangs outside of the body, they do not have the protection of muscles and bones.
This makes it easier for the testes to be struck, hit, kicked, or crushed, which occurs most often during contact sports.
A rare type of testicular trauma, called testicular rupture, occurs when a testicle receives a direct blow or is squeezed against the hard bones of the pelvis.
This injury can cause blood to leak into the scrotum and possibly even infertility and other complications.
[citation needed] In at least one case, testicular trauma was reported as the cause of a patient developing systemic inflammatory response syndrome (SIRS) despite otherwise minor trauma.