What is a MCL tear?
A MCL tear is an elbow injury that is occasionally seen in clinical practice, and is characterized by overstretching or tearing of the Medial Collateral Ligament (MCL) of the elbow. A ligament is a strong band of connective tissue which attaches bone to bone. The MCL is situated at the inner aspect of the elbow joint and is responsible for joining the inner aspect of the humerus (upper arm bone) to the inner aspect of the ulna (inner forearm bone) (figure 1). The MCL is one of the most important ligaments of the elbow, giving it stability. The MCL achieves this role by preventing excessive sideways movement of the elbow (valgus forces figure 2). If these sideways movements are excessive and beyond what the MCL can withstand, tearing to the MCL can occur. When this happens it is known as a MCL tear. A MCL tear may range from a small partial tear resulting in minimal pain, to a complete rupture of the MCL resulting in significant pain and disability. A MCL tear can be graded as follows:
