The SLAP tear is a specific injury to a part of the shoulder joint called the labrum. The shoulder joint is a ball-and-socket joint, similar to the hip; however, the socket of the shoulder joint is extremely shallow, and thus inherently unstable. To compensate for the shallow socket, the shoulder joint has a cuff of cartilage called a labrum that forms a cup for the end of the arm bone (humerus) to move within. This cuff of cartilage makes the shoulder joint much more stable, yet allows for a very wide range of movements (in fact, the range of movements your shoulder can make far exceeds any other joint in the body). A SLAP tear is a injury of this labrum.
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