What is the insertion point of the obturator externus muscle?

The insertion point of the obturator externus muscle is the trochanteric fossa of the femur. This specific location is significant as it serves as the site where the muscle plays a crucial role in the rotation of the thigh. The obturator externus originates from the external surface of the obturator membrane and the surrounding bone, passing through the lesser sciatic notch to insert into the trochanteric fossa. This positioning allows the muscle to effectively assist with external rotation of the hip joint, contributing to movements such as turning the leg outward, which is vital for various athletic and daily activities.

The other options, while relevant to the anatomy of the hip and thigh, do not represent the correct insertion point for the obturator externus. For instance, the gluteal tuberosity is primarily associated with the gluteus maximus muscle, while the linea aspera is a ridge on the posterior part of the femur for muscle attachment and does not relate to the obturator externus. The base of the lesser trochanter serves as an attachment point for the iliopsoas muscle and is not directly involved with the obturator externus muscle. Understanding the correct anatomical placements and functions of these muscles is essential for effective