To better understand the injuries and ailments associated with the hip, we have to understand how its components work together for healthy function.
The hip is essentially a "ball and socket" joint. Six key parts make up the hip:
- Femoral head: the “ball” which fits into the socket.
- Acetabulum: the “socket.”
- Articular cartilage: Covers the ball and socket, enabling the hip to move smoothly and painlessly.
- Labrum: a pliant ring of fibrocartilage that seals the acetabulum, serving as a kind of glue to keep the hip socket in place. The labrum also holds the lubricating fluid within the hip and contributes to its overall stability. Please note that a torn labrum is one of the most common causes of hip pain. In addition, when the labrum is torn, the "seal" is broken, and the joint may lose its stability and lubrication. This may lead to loss of cartilage, or arthritis.
- Capsule: an envelope of ligaments which encloses the hip and is also essential for stability.
- Ligamentum teres: located inside the hip, it connects the femoral head to the acetabulum. Both the capsule and the ligamentum teres can be injured in an unstable hip.
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