Question

Which joint maneuver increases the risk of an obturator neuropathy in a patient who is placed in a lithotomy position?

A) Hip flexion greater than 90 degrees
B) Trendelenburg position
C) Lumbar hyperextension
D) Hip abduction for greater than 30 degrees

Answer 1

Excessive hip abduction beyond 30 degrees in the lithotomy position increases the risk of obturator neuropathy, as it stretches the obturator nerve which is responsible for medial thigh muscle innervation.

Step-by-step explanation:

The correct option is D:

The joint maneuver that increases the risk of obturator neuropathy in a patient who is placed in a lithotomy position is Hip abduction for greater than 30 degrees (D).

Hip abduction beyond 30 degrees can stretch the obturator nerve, which innervates the medial thigh muscles, potentially leading to an obturator neuropathy. The lithotomy position inherently requires both hip flexion and abduction, but excessive abduction specifically stresses the obturator nerve the most. Therefore, careful positioning to avoid extreme angles is crucial to prevent nerve injury. While other factors such as the duration of the procedure and patient-specific anatomy can also contribute to the risk of nerve damage, the focus in this discussion is on the specific joint maneuver that most directly impacts the risk for the described complication. Other positions like hip flexion, Trendelenburg, and lumbar hyperextension are less directly associated with obturator neuropathy when compared to excessive hip abduction in the context of a lithotomy position.