Factors That Contribute to the Stability of Hip Joints

The hip joint is considered one of the body's most durable joints, making it very stable. It is a ball and socket joint and can be injured in various ways, including by conditions such as arthritis, necrosis and injury. The hip joint has three parts to it: the ilium, the femoral head and neck and the femur.

Bursae and Labrum

• Bursae are sacs found in the hip joint--and in other joints--that are filled with fluid. Bursae are located strategically within the hip joint to cushion places where tendons and ligaments are nonexistent. Bursae reduce or eliminate friction (irritation caused by the constant rubbing of bone on bone). The Labrum, a type of cartilage, also adds to the stability of the hip joint because it helps the bones to glide against one another and also eliminates friction and bone damage.

Ligaments

• Ligaments are located in the hip joint and help to make the joint stable by controlling how the joint moves. It keeps the joint stable and confines it to a certain range of motion, preventing it from slipping out of place or becoming misaligned. Ligaments are fibrous tissues that connect the femur to the pelvic bone.

Muscles and Tendons

• The muscles connected to the hip joint help to keep it in place and allow it to be mobile. Unlike ligaments, which connect bone to bone, tendons are fibrous tissues that connect bone to muscle. The muscles surrounding the hip joint depend on the connectivity of the tendons for fluid mobility and stability.

Symptoms of Unstable hip Joints

• When any of these stabilizing factors, whether muscles, tendons, ligaments, bursae or the labrum, are injured or become inoperable in some way, the stability of the hip joint greatly decreases. Instability can be caused by injury or various diseases and symptoms of hip joint instability include a frequent or constant popping or clicking of the hip, pain in the hip area, limited motion of the leg or pelvic region, and swelling or irregular positioning of the leg or hip.