APPLIED RADIOLOGICAL ANATOMY

Detailed explanation-1: -The prime movers (agonist) for hip flexion are the: Psoas major muscle, a long, tapering (fusiform) muscle that originates at either side of the spine and inserts at the lesser trochanter of the femur. The psoas muscle contracts when the hip is flexed.

Detailed explanation-2: -The four main groups of hip muscles are gluteal, adductor, iliopsoas, and lateral rotator, defined by the type of movement they mediate.

Detailed explanation-3: -The function of the psoas muscle is to connect the upper body to the lower body, the outside to the inside, the appendicular to the axial skeleton, and the front to the back, with its fascial relationship. Combined with the iliopsoas muscle, the psoas is a major contributor of flexion of the hip joint.

Detailed explanation-4: -The iliopsoas muscle is the strongest hip flexor and assists in external rotation of the femur, playing an important role in maintaining the strength and integrity of the hip joint. It is essential for correct standing or sitting lumbar posture, and during walking and running.