The hip joint is a complex ball-and-socket joint that supports the weight of the body and is responsible for the movement of the upper leg. It consists of two main parts including a ball (femoral head) at the top of the thighbone (femur) that fits into a rounded socket, sometimes referred to as the cup, in the pelvis. Bands of tissue, called ligaments, hold the joint together and provide stability.
The structure of the hip joint enables the large range of motion needed for daily activities like walking, squatting, and climbing stairs. The labrum helps the femoral head move smoothly within the socket. It lets your hip move without problems or pain. It also serves as a seal, keeping the ball and socket together but not touching.
Labral tears occur when the labrum is suddenly injured. Labral injuries can be the result of trauma, such as a fall or a vehicle accident, but are most commonly caused by repetitive stress to the hip joint. Additionally, labral tears are broadly classified into two separate categories, depending on where the labrum is torn:
- Anterior labral tear – An anterior labral tear is located at the front of the hip and is the most common. Two contributing factors to the development of anterior tears include hip joint stress, such as repetitive pivoting, and poor vascular supply to the hip joint.
- Posterior labral tear – This type of tear is located at the back of the hip. Posterior labral tears are associated with movements that put stress on the back of the hip joint, such as frequent squatting.
The majority of tears occur on the anterior side of the labrum, which is much wider and thinner than the posterior section. Also, labral tears can happen during playing sporting activities that require extremes in motion, repetitive twisting, or sharp movements like cutting. These are often found during a diagnostic process with a healthcare provider.