The 6-hour rule for testicular torsion salvage is the most time-critical principle in urology: 97% salvage at <6 hours, 70% at 12 hours, 20% at 24 hours, and <5% at 48 hours. Even 30 minutes' additional delay from GP to A&E can be the difference between salvage and orchidectomy. The clinical diagnosis (sudden acute scrotal pain + high-riding tender testis + absent cremasteric reflex) is sufficient to proceed directly to theatre without waiting for Doppler USS — if USS is unavailable or would delay theatre by more than 30 minutes, proceed to surgical exploration. A negative scrotal exploration showing epididymo-orchitis is an acceptable outcome — missing a torsion is not. In adolescents, always explain that torsion can occur without trauma and presents as sudden one-sided testicular pain.

Intermittent testicular torsion (torsion that self-reduces) is a critical but frequently missed diagnosis. It presents as recurrent episodes of acute scrotal pain lasting minutes to hours that resolve spontaneously. The underlying anatomy (bell clapper deformity — high attachment of tunica vaginalis allowing the testis to rotate freely) means that each episode is a torsion event. These patients require urgent urology referral for bilateral orchidopexy (securing both testes) to prevent a completed torsion. GPs should not reassure patients that "it resolved by itself" — intermittent torsion is a surgical emergency waiting to happen. Any teenage boy with recurrent unexplained testicular pain must be referred urgently to urology.

Torsion of the appendix testis (hydatid of Morgagni) is the most common cause of acute scrotal pain in prepubescent boys (7–12 years), and is more common than testicular torsion in this age group. The blue dot sign (a dark bluish discolouration at the upper pole of the testis, visible through the skin) is pathognomonic and allows conservative management when confidently identified. However, in practice this sign is only visible in 20% of cases — if there is any doubt, Doppler USS or surgical exploration should be performed. Chronic orchialgia (testicular pain for >3 months) affects approximately 1% of men and significantly impairs quality of life. It is frequently overlooked — patients may present repeatedly without clear diagnosis. A biopsychosocial approach is needed.

Doppler USS has a 10–15% false-negative rate for testicular torsion — intermittent torsion with spontaneous detorsion may show normal flow at the time of imaging, or early torsion may still have some residual flow. NICE guidance and urological practice both state that a normal Doppler USS in the context of high clinical suspicion for torsion should not preclude surgical exploration. Clinical findings (absent cremasteric reflex, high-riding testis, sudden onset severe pain) take precedence over imaging. The consequences of missing a torsion (orchidectomy) are permanent and irreversible; the consequence of a negative scrotal exploration (small incision, 20 minutes under general anaesthesia) is trivial by comparison.

Post-vasectomy pain syndrome (PVPS) affects 1–2% of men after vasectomy — it presents as chronic testicular pain (dull ache or sharp pain) beginning within months of vasectomy. The mechanism is unclear (sperm granuloma, epididymal congestion, nerve entrapment). Treatment is challenging — NSAIDs, amitriptyline, and pelvic floor physiotherapy are first-line. Vasectomy reversal resolves PVPS in 70% of appropriately selected cases. Epididymectomy is a last resort. GPs should warn patients about PVPS risk during vasectomy pre-counselling, and should recognise it when it presents rather than dismissing chronic post-vasectomy scrotal pain as "normal."

The 14-day antibiotic course for epididymo-orchitis is essential — shorter courses (<10 days) carry a high risk of treatment failure and chronic epididymitis, which causes chronic orchialgia and impairs fertility via epididymal scarring. Patient adherence to the full 14-day course must be emphasised. For chronic orchialgia, the neuromodulator approach (amitriptyline) is based on the recognition that many cases involve central sensitisation and neuropathic pain mechanisms — analogous to other chronic pain syndromes. A 6-week trial is needed before assessing efficacy. The spermatic cord block (injection of local anaesthetic around the spermatic cord) both confirms a scrotal origin for the pain (diagnostic) and provides temporary relief (therapeutic) — it can be used to guide further management.

Scrotal elevation is one of the most underused but most effective simple measures for acute scrotal pain — it reduces venous congestion in the scrotum (which lacks valves in the pampiniform plexus, unlike limb veins) and dramatically reduces pain. In hospital, the scrotum is elevated on a folded towel at all times. In primary care, advising firm-fitting underwear or a rolled towel under the scrotum while resting achieves the same effect. Patients can be advised to do this while waiting for 999 for suspected torsion — it is not harmful in torsion and significantly reduces pain from other causes.

Recurrent or bilateral epididymo-orchitis causes epididymal scarring that can significantly impair or eliminate sperm transit — it is one of the preventable causes of male infertility. The GP's role in chlamydia contact tracing and treatment is therefore a fertility preservation intervention as well as a public health measure. Semen analysis at 3 months after bilateral epididymo-orchitis is a reasonable safety net — early identification of sperm count changes allows timely fertility referral. The mental health burden of chronic orchialgia is substantial but rarely acknowledged — men may feel embarrassed discussing ongoing testicular pain and may present multiple times before receiving appropriate psychosocial assessment.

Fournier's gangrene (necrotising fasciitis of the perineum and scrotum) is a rare but rapidly fatal complication of scrotal infection — it has a mortality of 20–40% even with aggressive surgical debridement and intensive care. The early signs are severe perineal/scrotal pain disproportionate to apparent findings, fever, and skin erythema/crepitus. Any patient with scrotal infection who develops rapidly worsening pain, skin changes, or crepitus on palpation (indicating subcutaneous gas from anaerobic organisms) must be treated as a surgical emergency — 999 and pre-alert as a major surgical emergency. This is particularly a risk in diabetics and immunocompromised patients. PSA during acute prostatitis can be elevated to 50–100 ng/ml — this is a normal inflammatory response and must not be used as evidence of prostate cancer. Always wait 4–6 weeks after resolution before repeating PSA.