The medial collateral ligament (MCL) is one of the primary ligaments stabilizing the knee joint. When this ligament becomes stretched, sprained, or torn, it can result in pain and limited mobility. At Southern California Orthopedic Institute (SCOI), our board-certified, fellowship-trained knee specialists are experts in diagnosing and treating MCL injuries, helping patients of all activity levels recover safely and efficiently.
The medial collateral ligament (MCL) is located on the inner side of the knee and connects the thigh bone (femur) to the shin bone (tibia). It prevents the knee from bending inward and helps maintain joint stability during movement.
An MCL injury occurs when the ligament is stretched beyond its normal range or torn. It is common in contact sports like football, hockey, and soccer, but can also happen during daily activities, such as slipping on a wet surface or twisting the knee awkwardly. MCL injuries can range from a mild sprain to a complete ligament tear.
Recognizing the symptoms of an MCL injury early can help prevent further complications. Common signs include:
Many patients report sharp pain inside the knee, especially during side-to-side movements or pivoting.
MCL injuries are classified into three grades:
The severity of the injury will determine the treatment plan and recovery time.
A medial collateral ligament tear is often accompanied by a popping sound at the time of injury, followed by sharp inner-knee pain. A Grade III tear typically results in major instability and may prevent walking without support. Swelling and bruising may appear within hours, and the joint may feel loose or unstable when moving.
Walking with an MCL injury is sometimes possible, particularly in mild to moderate cases. However, pushing through the pain or instability may worsen the condition. Patients with a complete tear may be unable to walk without assistance. A knee brace or crutches may be recommended during early recovery.
MCL injuries typically result from an external force or twisting motions that stress the inner knee. Common causes include:
Athletes and active individuals are more likely to experience MCL injuries, though they can affect anyone.
At SCOI, diagnosing an MCL injury begins with a comprehensive physical exam. Your physician may perform stress tests to evaluate ligament stability. Imaging studies are often used to confirm the diagnosis:
Our orthopedic experts work closely with radiologists to ensure a precise diagnosis and create a personalized treatment plan.
Most MCL injuries do not require surgery. Conservative treatments are typically effective, especially for Grade I and II injuries. These may include:
Our therapists design rehabilitation programs that help patients recover safely while building resilience for future activity.
Surgery may be necessary for complete ligament tears or injuries that involve multiple knee structures (such as ACL and MCL tears). At SCOI, our orthopedic surgeons specialize in advanced surgical techniques, including minimally invasive procedures that promote faster recovery and less postoperative discomfort.
| Symptom | Grade I (Mild) | Grade II (Moderate) | Grade III (Severe) |
|---|---|---|---|
| Pain Level | Mild | Moderate | Severe |
| Swelling | Light | Noticeable | Significant |
| Instability | None | Slight | Major |
| Walking Ability | Unaffected | Painful but possible | Difficult |
| Treatment Approach | Conservative | PT + Bracing | Possible Surgery |
Southern California Orthopedic Institute is a recognized leader in diagnosing, treating, and rehabilitating MCL injuries. Here’s what sets us apart:
Whether you’re an athlete, a weekend warrior, or someone dealing with an unexpected injury, our team is here to help you move, feel, and get back to doing what you love. Call (818) 901-6600 or request your appointment today.
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