Testicular torsion occurs when the spermatic cord to a testicle twists, cutting off the blood supply (a condition called ischemia). The most common symptom is the rapid onset of acute testicular pain and prolonged testicular torsion will result in the death of the testicle and surrounding tissues (Ogunyemi, et al. 2018).
Generally, testicular torsion requires emergency surgery. If treated within a few hours, the testicle can usually be saved. However, waiting longer for treatment can cause permanent damage and may affect the ability to father children. When blood flow has been cut off for too long, a testicle may become so badly damaged it has to be removed.
Wearing underpants will not necessarily prevent testicular torsion. Males who get testicular torsion have an inherited trait that allows the testicle to rotate freely inside the scrotum. This inherited condition often affects both testicles (Mayo Clinic, 2018).
In men and boys who are at risk of testicular torsion, the condition often occurs with no apparent trigger. Testicular torsion often occurs several hours after vigorous activity, after a minor injury to the testicles or while sleeping. Cold temperature or rapid growth of the testicle during puberty also might play a role.
The risk factors are:
- Age
Testicular torsion is most common in males between 10 and 25 years old.
- Previous testicular torsion
A person that had testicular torsion that went away without treatment is likely to have it again in either testicle unless surgery is performed to correct the underlying problem.
- Climate
Torsions are sometimes called "winter syndrome". This is because they often happen in winter, when it is cold outside. The scrotum of a man who has been lying in a warm bed is relaxed. When he arises, his scrotum is exposed to the colder room air. If the spermatic cord is twisted while the scrotum is loose, the sudden contraction that results from the abrupt temperature change can trap the testicle in that position. The result is a testicular torsion.
Bell clapper deformity
In this deformity the testicle is only attached to the spermatic cord, like a bell clapper. A bell clapper deformity is a predisposing factor for testicular torsion in non-neonates. Currently there is no recommended clinical examination for a bell clapper deformity.
Having testicles that can rotate or move back and forth freely in the scrotum is an inherited trait. Some males have this attribute and others do not. The only way to prevent testicular torsion for a man with this trait is through surgery to attach both testicles to the inside of the scrotum so that they cannot rotate freely. (Brunner, 2010)
With these facts in mind, with exception of a slight plausability created through the climate issue, neither being clothed or practicing nudism/naturism (whichever you wish to call it) can prevent testicular torsion.
Other aspects aside from testicular torsion
With regards to protection from urine, semen and faeces, with good personal hygiene, these won’t pose a problem.
The combination of heat, sweat, and friction in your nether regions is not only uncomfortable, it can be unhealthy. Tight and non-breathable clothing traps heat and moisture, which can encourage the growth of candida, and lead to an unbearable yeast infection. That's not the only thing you have to worry about. When bacteria travel from back to front, it increases your risk for contracting an uncomfortable urinary tract infection (UTI) as well.
For men, the temperature of the testes is at issue: In order for testes to produce sufficient quality and quantity of sperm, the temperature of testes must be lower than the core body temperature.
"That is why [testes] are located outside of the body," explains Celia E. Dominguez, reproductive endocrinologist, Centre for Reproductive Medicine at the Emory University School of Medicine. "Testes were made to be out in the breeze." (Davis, 2004)
Testes can overheat when a man wears brief underwear. If the testes are too hot — several degrees above where they should be — they are not able to produce sufficient sperm, resulting in low sperm count.
References
Brunner, S. (2010). What Is Testicular Torsion? What Causes Testicular Torsion? Medical News Today [Online]
Retrieved from: http://www.medicalnewstoday.com/articles/190514.php
Davis, J. L. (2004). Boxers vs. Briefs: Increasing Sperm Count. WebMD [Online]
Retrieved from: http://www.webmd.com/infertility-and-reproduction/features/boxers-vs-briefs-increasing-sperm-count
Mayo Clinic. (2018). Testicular Torsion, Mayo Clinic [Online]
Retrieved from: https://www.mayoclinic.org/diseases-conditions/testicular-torsion/symptoms-causes/syc-20378270
Ogunyemi, O. I., Weiker, M., & Abel, E. J. (2018). Testicular Torsion, Medscape [Online]
Retrieved from: https://emedicine.medscape.com/article/2036003-overview#showall