Medial Collateral Ligament (MCL) Tears
What is the MCL?
The medial collateral ligament (MCL) is one of two collateral ligaments about the knee joint. The MCL stabilizes the medial aspect (inner side) of the knee, connecting the thigh bone (femur) to the shinbone (tibia). It functions to prevent the knee from being forced too far inward while still allowing the knee to rotate.
Injury to the MCL is the one of the most common injuries in skiing. Overall, MCL tears are two to three times more common than ACL tears. MCL injuries are very common with almost 750.000 injuries occurring every year in the United States.
What are the symptoms of an MCL tear?
When an MCL ligament is torn or sprained, the patient may feel a pop followed by pain, swelling and tenderness. Symptoms depend on the severity of the injury. Severity is graded on a scale from 1 to 3. A Grade 1 is a sprained ligament, a mild injury that presents with mild pain and tenderness over the ligament attachments, but with no instability. A Grade 2 is a partial tear that presents with moderate pain, swelling and instability. A Grade 3 tear is a complete tear of the ligament and presents with severe pain and tenderness, swelling, and instability.
What causes an MCL tear?
The most common cause of an MCL tear is a direct impact on the outside of the knee. However, repetitive stress can stretch and eventually tear the MCL. MCL tears often accompany an ACL injury.
What is the most accurate way to diagnose an MCL tear?
Dr. Jonathan Godin will ask you about how and when you were injured, your medical history and history of knee injuries, and your goals for recovery. During the physical exam he will look for pain and tenderness, test range of motion and conduct specific tests comparing the injured knee with the healthy knee. With this information he will form a diagnosis. Dr. Godin will order stress x-rays to compare the gapping on the inside of the injured knee to that on the uninjured knee. MRI imaging may be ordered to check for other injuries and to determine the extent of the tear.
What is the immediate treatment?
The initial treatment for most grades of tears is designed to reduce pain and swelling, and will include the use of anti-inflammatory medications, rest, ice, compression and elevation. Most Grade 1 and 2 injuries can be treated conservatively with physical therapy, bracing and activity modification.
Activity modification and bracing will protect the knee while the tear heals. Physical therapy will begin soon thereafter to improve strength, balance and flexibility and help the healing process. Many Grade 1 & 2 MCL tears can heal on their own within 6 weeks with medical management. When the ligament does not heal and you are experiencing knee instability, the risk of re-injury is high. In this case surgery may be recommended.
Surgery
Grade 3 tears usually occur along with an ACL tear and are almost always treated with surgery. There are other situations where surgery is recommended to repair or reconstruct a MCL tear. First, if the knee gaps open on the outside when the knee is fully extended (valgus gapping in extension), the likelihood of the MCL healing without surgery is very low as the posterior oblique ligament (POL) is usually injured as well. The second type of injury requiring surgery is a tear of the MCL tibial (shin bone) attachment that retracts toward the knee. This is called a meniscotibial MCL tear. These types of tears also usually don’t heal on their own. This is because the torn and retracted MCL becomes trapped above the hamstrings tendons, and it cannot heal back down to the tibia (shin bone). When there is a complete tear of the MCL and when other knee structures are damaged, surgery should be performed within a few weeks after injury. Early surgery is beneficial to prevent scarring, healing in an abnormal position and to repair damaged tissues. Failure to treat a grade 3 MCL tear with other injuries can lead to chronic instability and disability.
Surgical reconstruction is designed to restore normal anatomy. There are multiple techniques including augmenting a repair of the torn MCL with a graft, or a full reconstruction of the MCL. If a complete posteromedial knee injury has occurred, Dr. Godin may recommend reconstructing both the MCL and the POL. Recent ligament reconstruction and augmentation surgical techniques have allowed many patients to get back to high-level activities.
How long does it take to recover from surgery?
Depending on the severity of the injury and the associated ligaments injured, recovery can take between 6 and 12 months. Physical therapy starts on day 1 to work on range of motion. Although return to sports varies by patient, it may be possible within approximately 9 to 12 months.