The most common causes of acute or subacute pain include but are not limited to:
Epididymitis: an infection of the epididymis, a structure composed of tightly packed tubules that carry the sperm from them testicle to the vas deferens, where it it routed to the urethra, the tube from the bladder through the penis. Epididymitis is primarily caused by backflow of urine up the vas deferens to the epididymis. This backflow is often the result of an abrupt activity that increases bladder pressure such as heavy lifting, landing after a parachute jump, or falling from a horse, but many patients can’t recall an inciting event. The urine causes inflamation in the tubes which allows infection to set in. Associated symptoms can include fever, nausea, and abdominal pain. Treatment usually includes antibiotics for 10-14 days, anti-inflammatories, ice packs, and elevation. If treatment is delayed, a chronic condition can develop.
Testicular torsion: is a condition that is most common from late adolescence to young adulthood, and is often trauma related. Most testicles are attached within the scrotum so that they will not twist on their blood supply, but in some men the testicle can twist more than 360 degrees causing obstruction of the blood supply. The pain with testicular torsion can be very severe, and is often associated with nausea and vomiting. The onset is usually rapid, and the pain can be intermittent if the testicle untwists and then twists again. Testicular torsion is a true surgical emergency. A testicular ultrasound is needed to clarify the diagnosis. If the testicle is not detorsed or untwisted quickly, testicular death can occur. An interval of torsion greater than 12 hours will result in testicular loss in most cases.
Torsion of a testicular appendage: is a condition that can mimic testicular torsion, but the pain is usually not as severe. In such cases, the appendix testes and the appendix epididymis (small vestigial structures from birth) can twist and cut off their blood supply. When this occurs, the appendix will initially swell then become tender and bluish in color. If a patient is examined soon after onset, a blue dot can be seen beneath the skin particularly if the patient has a fair complexion. If the blue dot is seen, then the treatment can be observation. Surgical excision can speed recovery as it can take 1-2 weeks for the inflammation to resolve without treatment. If too much time passes before evaluation, the inflammation becomes more severe and the blue dot sign is lost. The diagnosis becomes less clear, and surgical intervention to remove the appendage will often be required to speed recovery and insure that the testicle torsion is not the culprit.
Delayed post vasectomy pain is an infrequent condition where the epididymis, which is under pressure from continued sperm production by the testicle, may leak a little sperm into the surrounding tissues. This is commonly referred to as an “epididymal blowout” and results in the sudden onset of testicular pain followed by the appearance of a marble sized, hard, tender knot on the perimeter of the testicle. The inflammation will mimic epididymitis, but if there has been a vasectomy, urine cannot reach the epididymis to cause the problem. This condition is best managed with ice and anti-inflammatory medication like Ibuprofen or Naproxen. Antibiotics can be prescribed if the diagnosis is not clear.
Testicular trauma usually from a blow to the testicle can result in acute testicular pain as most men are aware. Usually, the initial sharp pain is transient followed by a dull achiness, but if the pain remains severe or is associated with significant swelling, testicular rupture needs to be considered. A scrotal ultrasound will help determine whether the testicle is ruptured or torsed. A rupture will be associated with a disruption of the capsule of the testicle, presence of fluid, or blood around the testicle. The ultrasound can also identify testicular bruising or subcapsular hematomas. A ruptured testicle should be repaired surgically and may require removal if severely injured.
Secondary causes of testicular pain can include kidney stones, herniated discs, and hernias. The nerve supply for the kidney and testicle has a similar origin so kidney pain can radiate to the testicle. A ruptured disc compressing a spinal nerve root can cause variably severe achy testicular pain that is often positional. The testicular innervation is primarily through the L1 nerve root. Pain radiating into the leg, scrotum, and inner thigh is often associated with the nerve root pain. An inguinal hernia can occasionally cause acute testicular pain, but the pain symptoms with a hernia tend to be more chronic.