Medial rotation – anterior fibres of gluteus medius and minimus, tensor fascia latae.

Lateral rotation – biceps femoris, gluteus maximus, piriformis, assisted by the obturators, gemilli and quadratus femoris.

Adduction – adductors longus, brevis and magnus, pectineus and gracilis.

Abduction – gluteus medius, gluteus minimus, piriformis and tensor fascia latae.

Extension – gluteus maximus semimembranosus, semitendinosus and biceps femoris (the hamstrings).

Flexion – iliopsoas, rectus femoris, sartorius, pectineus.

The movements that can be carried out at the hip joint are listed below, along with the principle muscles responsible for each action:

Posteriorly, where the ligaments are weakest, the medial rotators are greater in number and stronger – they effectively ‘pull’ the head of the femur into the acetabulum.

Anteriorly, where the ligaments are strongest, the medial flexors (located anteriorly) are fewer and weaker.

In addition, the muscles and ligaments work in a reciprocal fashion at the hip joint: These ligaments have a unique spiral orientation this causes them to become tighter when the joint is extended. The iliofemoral, pubofemoral and ischiofemoral ligaments are very strong, and along with the thickened joint capsule, provide a large degree of stability. The increase in depth provides a larger articular surface, further improving the stability of the joint. There is a horseshoe shaped fibrocartilaginous ring around the acetabulum which increases its depth, known as the acetabular labrum.

This decreases the probability of the head slipping out of the acetabulum (dislocation). It is deep, and encompasses nearly all of the head of the femur. There are a number of factors that act to increase stability of the joint.

The primary function of the hip joint is to weight-bear. It has a spiral orientation, and prevents hyperextension and holds the femoral head in the acetabulum.Ischiofemoral– spans between the body of the ischium and the greater trochanter of the femur, reinforcing the capsule posteriorly.It has a triangular shape, and prevents excessive abduction and extension.Pubofemoral – spans between the superior pubic rami and the intertrochanteric line of the femur, reinforcing the capsule anteriorly and inferiorly.It is the strongest of the three ligaments. It has a ‘Y’ shaped appearance, and prevents hyperextension of the hip joint.Iliofemoral ligament – arises from the anterior inferior iliac spine and then bifurcates before inserting into the intertrochanteric line of the femur.There are three main extracapsular ligaments, continuous with the outer surface of the hip joint capsule: It encloses a branch of the obturator artery (artery to head of femur), a minor source of arterial supply to the hip joint. It is a relatively small structure, which runs from the acetabular fossa to the fovea of the femur. The only intracapsular ligament is the ligament of head of femur. They can be divided into two groups – intracapsular and extracapsular: the unaffected leg is bent to stabilize the patient position i.e.The ligaments of the hip joint act to increase stability.the patient is rolled at least 45° onto the side of interest with a hip flexion of 90°.As this particular projection involves rolling the patient onto the side of interest, it is hence not suitable for trauma situations.įor trauma imaging of the hip, see: horizontal beam lateral. suspected osteoarthritis of the hip) in an orthogonal plane to the AP projection. This view assesses the hip joint for any potential fractures, dislocations, bone lesions or degenerative diseases (i.e.

Normal male hip xray