What nerve is at risk of injury if the legs are improperly flexed at the hip during lithotomy positioning?

In lithotomy positioning, the legs are elevated and flexed at the hips to facilitate surgical access to the pelvic area. This positioning can place stress and strain on certain nerves, particularly if the legs are flexed improperly. The obturator nerve, which runs along the inner side of the pelvis and innervates the adductor muscles of the thigh, is particularly susceptible to injury in this scenario. If the legs are excessively flexed or positioned improperly, this could result in compression of the obturator nerve, leading to potential complications such as motor weakness or sensory loss in the medial thigh area.

The obturator nerve's proximity to the hip and its path through the pelvis make it a key nerve at risk during lithotomy positioning. Maintaining proper leg positioning is critical to avoiding outcomes that could impair function related to this nerve, highlighting the importance of careful setup during surgical procedures.