Testicular pain: causes and when it is an emergency

The testicle hangs in the scrotum on the spermatic cord, which carries an artery, veins and the vas deferens. In torsion the cord rotates around its own axis: first compressing the thin-walled veins (the testicle swells) and, after further rotation, the artery as well (the testicle stops receiving blood). From that moment the testicular tissue lives on its oxygen reserve, and every additional hour increases the proportion of cells that will die. There is no threshold after which 'it is too late' and none before which 'it is surely fine': the risk curve rises gradually, which is why the advice is to operate as soon as possible, regardless of how many hours have passed.

Torsion is most common in teenagers and young men, but it can occur at any age, including adults in their thirties, which is sometimes underestimated because epididymitis is more often suspected in older patients. The typical picture is sudden, severe pain on one side of the scrotum or lower abdomen (sometimes felt mainly in the groin or lower belly), nausea and vomiting, a testicle that sits higher and more horizontally, an absent cremasteric reflex (the testicle does not rise when the inner thigh is stroked) and tenderness that does not ease when the scrotum is lifted. The pain may begin at night or after exertion, but just as often without any identifiable trigger.

Not every torsion is a single full turn. Intermittent torsion exists: pain appears, resolves after tens of minutes or hours, and returns. Such an episode, even if it has passed, is a signal for urgent work-up within a day or two rather than a reason for reassurance, because in some of these patients the next episode ends in complete torsion. For the same reason, 'it went away by itself so it was nothing' is not a good guide after sudden, sharp testicular pain.

These numbers should be read with caution. First, this is an observational, retrospective study: it shows an association between time and testicle loss, but in reality time is linked to other factors (degree of twist, age, how quickly the patient reached a centre with a urologist). Second, a 'saved testicle' means a testicle left in place during surgery, not a guarantee of full function years later. Third, the population was adults and adolescents, so these thresholds must not be applied directly to newborns or small children. The practical conclusion is nevertheless consistent with the entire literature: the sooner the better, and a window of about 6 hours is not a boundary after which 'it is no longer worth it', only the point from which the risk starts to rise faster.

Inflammation of the epididymis (epididymitis) or of the epididymis and testicle (epididymo-orchitis) is the most common infectious cause of scrotal pain in adults. The pain usually builds over one to several days, is localised along the back and upper part of the testicle (where the epididymis lies), and is often accompanied by fever, swelling, redness of the scrotal skin and sometimes urinary symptoms: urgency, burning, urethral discharge. Lifting the scrotum may bring relief (Prehn's sign), but this sign is unreliable and should not be used to exclude torsion.

Two practical points follow from this study. First, epididymitis is predominantly bacterial, so it is treated with an antibiotic chosen according to age and risk factors (in younger sexually active men sexually transmitted pathogens are considered; in older men, intestinal bacteria from the urinary tract), not with painkillers alone. Second, age does not exclude chlamydia, so the choice of treatment and the testing of a partner should be discussed with the doctor. Specific antibiotic regimens depend on guidelines (European, American) and local resistance; choosing them is the doctor's task and should not be based on a drug from the home medicine cabinet.

Mumps orchitis (caused by the mumps virus) is rarer today thanks to vaccination but is still reported, especially in unvaccinated teenagers and young adults. It is usually accompanied by painful swelling of the parotid glands and affects one testicle. So if testicular pain appears after contact with someone who has mumps, it is worth telling the doctor.

Not every pain felt in the testicle comes from the testicle. The ilioinguinal nerve, the genitofemoral nerve and the coeliac plexus connect the scrotal region with the groin, the kidney, the ureter and the lower spine. For this reason a ureteric stone, especially in the lower ureter, can be felt as pain radiating to the testicle, while the testicle itself is not tender on palpation. Similarly, an inguinal hernia, especially one descending into the scrotum, can cause pain and a feeling of heaviness that worsens after exertion and in the evening. A strangulated hernia (hard, painful, not reducing when lying down, with vomiting and no passage of gas) is a separate emergency.

A separate category is chronic scrotal content pain (CSCP), also called chronic testicular pain (orchialgia). It is defined as pain localised in the scrotum, lasting at least three months and interfering with daily functioning; according to a review of treatment algorithms (Kravchick et al., 2024) it accounts for about 2.5% of all urology outpatient visits. The cause may be earlier groin surgery or vasectomy, inflammation or nerve compression, and often it cannot be established. Management is stepwise (exclusion of acute causes, conservative treatment, nerve blocks, surgery in selected cases), and the evidence for individual methods is limited, so this is a topic for a urologist rather than for home experiments.

The doctor starts with a history: when and how the pain began, whether it is sudden, whether there have been similar episodes, whether there is fever, urinary symptoms, an injury or a risky sexual contact. Then the scrotum and groins are examined standing and lying down: the size and position of the testicles are compared, the cremasteric reflex is checked, the point of greatest tenderness is identified, and firmness and any lump are assessed. In young patients with acute pain, clinical scores (for example the TWIST score) are also used, combining several signs into one number and helping to decide whether an ultrasound is enough or the patient should go straight to surgery. These scores are helpful but must not be treated as infallible: when torsion is strongly suspected, waiting for additional tests should not lengthen the time to the operating theatre.

Ultrasound with a Doppler option assesses blood flow in the testicle: in torsion the flow is reduced or absent, and the cord itself may be visible as a twisted structure (the whirlpool sign). The same examination helps distinguish epididymitis (an enlarged, hyperaemic epididymis with increased flow), hernia, fluid in the tunica vaginalis, cysts, varicose veins and tumours. It is worth remembering a limitation, though: an ultrasound result is not infallible, and a partial or intermittent torsion may give an image with preserved flow. If the clinical picture strongly suggests torsion and the ultrasound is equivocal or unavailable, the decision to explore surgically may be taken without waiting. The operation consists of untwisting the cord, assessing the viability of the testicle and fixing it with sutures, usually on the opposite side as well, because the anatomical predisposition is often bilateral.

See a doctor within a few days for: a new lump or enlargement of a testicle, a feeling of heaviness and hardening, blood in the semen or urine, pain lasting longer than a few days, a change in the size of one testicle, discharge from the urethra. Dull, chronic pain lasting for months is worth discussing with a urologist on a planned basis.

Testicular pain is not a topic in which over-caution is a mistake: in torsion an hour of delay has a measurable cost, while an unnecessary visit to the emergency department costs a few hours. In other cases, that is inflammation, hernia, varicocele or chronic pain, the pace is not as critical, but a doctor should examine pain that lasts longer than a few days or is accompanied by a lump. The evidence behind our recommendations comes mainly from observational studies and reviews of low to moderate quality, but the direction is consistent across all of them.