Hip Joint

The **hip joint** is a multiaxial ball-and-socket joint formed between the head of the femur and the acetabulum of the hip bone. Carrying the body's weight, the hip joint requires significant strength and stability, especially during standing and walking, resulting in a more restricted range of motion than the shoulder joint. The acetabulum, the socket portion of the joint, is deep and provides a large articulation surface for the femoral head, enhancing stability and load-bearing capacity. This stability is further reinforced by the acetabular labrum, a fibrocartilage lip that attaches to the acetabulum’s outer edge, deepening the socket. The surrounding articular capsule is robust, with thickened areas forming intrinsic ligaments that extend from the acetabular margins of the hip bone to the femur's neck. These ligaments tighten when the hip is extended, securing the femoral head firmly into the acetabulum in an upright standing position, thereby stabilizing the joint with minimal muscle contraction. The hip joint also contains an intracapsular ligament, which, though typically lax and not a primary source of joint stability, serves as a conduit for an important artery supplying blood to the femoral head. *LICENSES AND ATTRIBUTIONS CC licensed content, Shared previously Chapter 9. Authored by: OpenStax College. License: CC BY: Attribution. License Terms: Download for free at http://cnx.org/contents/R3D4RG6w@4/Anatomy-of-Selected-Synovial-J.*