An Extremely Rare Case of a Sciatic Nerve Variant.

The sciatic nerve (SN) is the nerve of the posterior compartment of the thigh and typically traverses beneath the piriformis muscle (PM) before continuing along a vertical course deep to the gluteus maximus and biceps femoris. However, cadaveric studies have often revealed significant variations in the structural features of the SN in relation to the piriformis. Knowledge of such variations is not only useful for clinicians treating pathophysiologies such as piriformis syndrome and sciatica but is also essential for surgeons carrying out procedures involving the hip and sacroiliac joints to avoid iatrogenic injury to the SN. During routine cadaveric dissection, one such anatomical variant was identified with the SN passing over the superior border of the piriformis muscle. To our knowledge, such a variant is exceedingly rare.