PT Tip of the Month Archive

Medial and Lateral Collateral Ligament Sprains/Tears

Knee anatomyThe knee is a complex, important joint that connects the femur (thigh bone) and tibia (shin bone) together. It is supported by a number of ligaments and muscles that help stabilize the joint and allow for movement. Two of the more important ligaments are known as the medial collateral (MCL) and lateral collateral (LCL) ligaments. These two ligaments are located on the inside and outside of the knee, respectively. The collateral ligaments mainly stabilize the knee against lateral (sideways) forces during movement. Just like any other ligaments in the body, these two are prone to injury or tearing.

Cause of injury

Collateral ligament injuries will happen whenever there is a force that causes the knee to be pushed sideways. This is why injuries occur more often during athletic activities that involve direct contact such as football or soccer. The MCL is injured when there is a direct blow to the outside of the knee, and the LCL is injured with a direct blow to the inside of the knee. These ligaments can also be injured with a sudden change in direction, with twisting of the joint or during a fall. The MCL tends to be injured more frequently than the LCL. Many times these injuries do not happen in isolation, and are associated also with an ACL tear and/or a meniscus tear.

What is a ligament sprain?

Knee injury gradesA sprain is an overstretching of a ligament and can fall under one of three grades. A grade I injury involves mild damage, with just a small overstretch and the knee joint remaining stable. A grade II injury involves stretching to the point where the ligament becomes loose – this is also known as a partial tear. A grade III injury is a complete tear of the ligament, where the ligament is in two pieces and the joint is unstable.





Symptoms of a LCL/MCL tear/sprain will generally include pain on either side of the knee, as well as swelling/edema around the knee joint. Many times even if there is not severe pain there will be a complaint of the knee feeling unstable, especially when trying to run, pivot or turn.


Knee braceGenerally surgery is not required for a collateral ligament injury because the ligament is able to heal well with a combination of activity modification, wearing a knee brace and physical therapy. Physical therapy will often include modalities and massage for pain-relief and edema reduction, as well as strengthening and stretching exercises to regain normal movements. If the injury that caused the tear was traumatic enough or if other structures such as the ACL or meniscus were torn, then surgery may be required. For more severe injuries diagnosis will often be done by MRI. If you have suffered a recent knee injury and would like to schedule an evaluation, please call 617-232-PAIN for our Brookline office, or 617-325-PAIN for our West Roxbury office.

33 Pond Avenue, Suite 107B Brookline, MA 02445 Tel: (617) 232-PAIN (7246) Fax: (617) 232-5196
1208B VFW Parkway, Suite 202 West Roxbury, MA 02132 Tel: (617) 325-PAIN (7246) Fax: (617) 325-7282