Its description, causes, symptoms, diagnosis and treatment (operative and non-operative)
The medial collateral ligament (MCL) is the main stabilizing ligament on the inner aspect of the knee. Its main function is to prevent the knee from buckling inward/knock-knee (valgus motion). Tears/ruptures of the ligament results in knee instability.
What are the causes?
MCL tears are typically caused by trauma. A direct force to the outside of the knee stresses the ligament. This typically occurs in collision sports like football. Overuse injuries in sports/occupations that require repetitive falling to the knees and standing up quickly can also lead to micro tears of the ligament
What are the symptoms?
MCL tears cause immediate pain and often swelling. You may feel something “pop” on the inside aspect of the knee. Pain is centralized over the ligament (inside aspect of the knee). Walking after the injury may be possible but the knee may feel like it’s going to “give in” depending on the severity of the tear. The MCL is attached to the underlying meniscus. Damage to the meniscus at the time of injury may cause clicking or locking of the knee.
How is it diagnosed?
Your surgeon will perform a thorough history and physical exam with X-rays. On exam, swelling and loss of motion and strength is present. Your surgeon will perform maneuvers to check stability of all the knee ligaments and the meniscus. An MRI is helpful to confirm the diagnosis, showing the MCL tear. The type of tear (partial, complete, avulsion from either the tibia or femur) can be defined, which may assist in treatment planning. The MRI may also show bone bruising secondary to the injury.
How is it treated?
Non-operative - Almost all minor MCL tears can be treated non-operatively. Non-operative treatment consisting of bracing, anti-inflammatory medication, physical therapy, cryotherapy and activity modification may be prescribed to decrease the swelling, regain motion and strength. Most patients may be able to return to normal activity without surgery depending on the type and severity of the tear. A brace may be prescribed to return to sports activities. If symptoms persist (pain, instability), reconstruction surgery may be recommended by your surgeon.
Operative - Operative management of MCL tears depends on the type of tear. MCL repair may be indicated in patients where the MCL is clearly torn off the wall of the femur (thigh bone) or tibia (shin bone. MCL repair is accomplished through a series of small incisions and sewed back into place and fixed with screws or buttons. The repair may also be supplemented with high-strength suture.
If formal reconstruction is required, a new MCL graft will be fixed in place of the original ligament. A technique for graft placement and graft choice is a shared decision between you and your surgeon. Most techniques are performed through a minimally-invasive incision. The graft can be taken from around your knee or from a donor. Postoperative rehabilitation, return to daily activities and return to sport depends on the technique and graft chosen, and is at your surgeon’s discretion.