Hip joint and its extracapsular ligaments

The stability of the hip joint is increased with the help of two groups of ligaments. They are named based on their location in relation to the articular capsule - intracapsular ligaments and extracapsular ligaments.

The intracapsular ligaments are located inside the hip joint cavity. In contrast, the extracapsular ligaments are situated outside the capsule and are continuous with its outer surface.

There are four strong extracapsular ligaments:

• Zona orbicularis - begins at the anterior inferior iliac spine; it surrounds the neck of the femur and ends where it began; the zona orbicularis is formed by the circular fibers of the articular capsule of the hip joint;
• Iliofemoral ligament - extends between the anterior inferior iliac spine and the intertrochanteric line; it is the strongest ligament in the human body; it is also known as the ligament of Bertin or Y ligament of Bigelow;
• Pubofemoral ligament - stretches from the superior pubic ramus to the intertrochanteric line;
• Ischiofemoral ligament - extends between the body of the ischium to the trochanteric fossa.

Movements of the hip joint

The hip joint enables the following movements:

• Flexion and extension

• Abduction and adduction

• Internal and external rotation

• Circumduction