Scrotal pain and testicular torsion: Viva

Branch 1: Classification and pathophysiology

The candidate should define testicular torsion as the twisting of the spermatic cord on its long axis that occludes the testicular blood supply and causes ischaemic testicular loss within hours. A strong candidate classifies it by where the twist occurs: intravaginal torsion, the common adolescent form inside the tunica vaginalis on a bell-clapper deformity; extravaginal torsion, the perinatal form where the whole cord and its coverings twist before the tunica fuses; and intermittent torsion, recurrent self-limiting episodes that risk a future complete torsion. ^[1]

If the examiner presses on the pathophysiology, the candidate should follow the blood. The twist compresses the thin-walled veins and lymphatics first, producing congestion and rising pressure within the inelastic tunica albuginea, and that rising pressure then collapses the artery, converting a congested perfused testis into an ischaemic one. The candidate should name the salvage gradient as the consequence: 90 to 100 percent within 6 hours, about 50 percent from 6 to 12 hours, and less than 20 percent from 12 to 24 hours, which is why time drives every decision. ^[1]