Hip and knee pain concomitant with herpes zoster of the saphenous nerve: A unique case report

Background: Herpes zoster is the result of the activation of latent varicella-zoster virus, which multiplies within a sensory ganglion and travels along the nerve to the skin. The classical manifestation is a unilateral dermatomal, vesicular rash. The intercostal herpes zoster is the most described localization. Localization in the saphenous was never described before.

Case report: We report the case of a 65-year-old patient who presented symptoms of herpes zoster in an uncommon and undescribed location corresponding to the territory of the saphenous nerve. The symptomatology was accompanied by hip and knee pain, attributed to the obturator nerve's concomitant participation. The literature has reported a case with motor or adjacent dermatome participation probably caused by the inflammatory reaction in the posterior corn.

Conclusions: The localized eruption, the favourable evolution of hip and knee pain in parallel with the regression of the rash, and the review of the literature conclude with the diagnosis of herpes zoster of the saphenous nerve and suggest the participation of the femoral or the obturator nerve.