An MCL injury, or injury to the medial collateral ligament, is a type of knee injury that affects the ligament on the inner side of the knee. The MCL is responsible for stabilizing the knee joint and preventing it from bending inward too far. MCL injuries are commonly caused by direct blows to the outside of the knee, sudden changes in direction, or twisting motions of the knee.

MCL injuries are classified into three grades, depending on the severity of the injury:
- Grade 1: Mild MCL sprain, where the ligament is stretched but not torn.
- Grade 2: Partial tear of the MCL, with some degree of instability in the knee joint.
- Grade 3: Complete tear of the MCL, resulting in significant instability in the knee joint.
Symptoms of an MCL injury may include pain and tenderness on the inner side of the knee, swelling, bruising, stiffness, and difficulty or discomfort while walking or bearing weight on the affected leg. In more severe cases, there may be a feeling of the knee “giving way” or buckling, indicating instability.
Treatment for an MCL Injury
Treatment for an MCL injury depends on the severity of the injury. Mild to moderate MCL injuries (Grade 1 and Grade 2) are typically treated conservatively with rest, ice, compression, elevation (RICE), and immobilization with a knee brace or a supportive wrap. Physical therapy may also be recommended to help with pain relief, swelling reduction, and to restore knee strength and stability.
Example MCL Exercises
Here are some examples of physical therapy exercises and techniques that may be used to help recover from an MCL injury:
- Range of motion exercises: Gentle exercises to help restore the full range of motion of the knee joint, such as heel slides and knee extensions.
- Strengthening exercises: Exercises to help strengthen the muscles around the knee joint, such as quad sets, hamstring curls, and calf raises.
- Balance and stability exercises: Exercises to improve balance and stability of the knee joint, such as single-leg stands and balance board exercises.
- Manual therapy: Hands-on techniques, such as massage and joint mobilization, to help reduce pain and improve mobility.
- Electrical stimulation: The use of electrical current to stimulate the muscles and promote healing.
- Cryotherapy: The use of ice or cold packs to help reduce pain and inflammation.
- Heat therapy: The use of heat or warm packs to help improve circulation and reduce stiffness.
It is important to work with a licensed physical therapist who can create a personalized treatment plan based on your specific injury and needs.
Additional Article.
- MCL Injuries (WebMD article)
- MCL Injury: What to Know (WebMD article)
- Runner’s Knee: What You Need to Know (WebMD article)
- MCL Injury and Treatment (Stanford Healthcare)