The lateral collateral ligament is a tough strap of tissue found on the outside of a person’s knee. This ligament connects the femur, which is the bone of the thigh, to the fibula, which is the smaller of the two bones in the lower part of the leg. It works to give the knee stability and stop it from moving too much.
The lateral collateral ligament works with another ligament called the medial collateral ligament. The medial collateral ligament is found on the side of the knee that faces the other leg. Together the two ligaments stop the knee from moving too much to either side.
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Sometimes the lateral collateral ligament is injured. This often occurs when a person sustains a hard hit to the knee, particularly one that impacts the inner portion of the knee. When this type of blow hits the knee, the ligament on the outside of the knee stretches and may tear. This may happen while a person is playing football, after he is hit with an object, as the result of a kick, or in a collision with another person.
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A tear to the lateral collateral ligament can be a very painful injury. A person may experience bleeding as well as swelling of the tissues surrounding the ligament, which causes stiffness, pain, and instability. In some cases, a person may develop a chronic ligament problem even after the initial injury has healed. If the injury doesn’t heal well enough to adequately support the knee, a person may deal with frequent pain and instability. The knee may even give way from time to time, failing to support the affected person’s weight.
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Treatment of a torn lateral collateral ligament may depend on the extent of the injury. Sometimes rest, ice, and elevation of the leg may allow it to heal on its own given enough time. Over-the-counter pain relievers, such as ibuprofen, are often recommended for keeping the patient comfortable. Physical therapy may play an important role in healing, helping the patient to regain strength and return to his normal range of motion. Usually, physical therapy begins when the patient’s swelling has gone down.
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In some cases, surgery is required to treat a torn lateral collateral ligament. For example, a surgeon may reattach a ligament after it has separated from the femur or tibia. If the ligament has torn in the middle, he may sew the edges of the ligament back together again. Sometimes damage to the ligament is so severe that a surgeon has to reconstruct it using tendon tissue from another part of the body.