Decoding MCL tears

MCL tears are often graded on the basis of their severity. Here’s more about the injury and its treatment

Do you know what’s common between Jay Cutler, Hines Ward, Knowshan Moreno, and Troy Polamalu? Well, all of these sportspersons have suffered from a medial collateral ligament (MCL) injury on the field. But, what’s an MCL tear? It is a common knee injury, mostly spotted in people who play sports like football, basketball and skiing. These injuries can occur either alone or in combination with other ligament and cartilage injuries of the knee.

In this type of injury, damage is caused to the medial collateral ligament. This is an important ligament located on the inner side of the knee. In some cases, the tear can be partial as only some fibers in the ligament are torn. It can also be caused as a complete tear, in which the ligament is torn into two pieces. Ligaments are tough band of tissues which connect one bone to another bone or hold organs in place.

What’s an MCL?

The length of this ligament is about 8 to 10 centimeters. It acts as a connector between the thigh bone (femur) and shin bone (tibia). It is responsible for providing strength and stability to the knee joint. There are four primary ligaments in the knee. Three of these ligaments are anterior cruciate ligament (ACL), lateral collateral ligament (LCL) and posterior cruciate ligament (PCL). The fourth one is the MCL.

The MCL is made up of collagen fibers and provides “side-to-side” stability to the knee. It also prevents widening of the inner aspect of the joint.It is observed that when significant forces are applied to the outside aspect of the knee—for instance during a tackle in football—MCL can be sprained or torn.

The MCL has a superficial and a deep layer. The superficial MCL runs from the distal femur to the tibia. It is foundbelow the sheath of the sartorius muscle tendon. The deeper MCL layer is located outside of the knee capsule. It inserts directly into the tibial plateau and medial meniscus.

Symptom and classification of the injury

In case of MCL tear, pain is experienced directly over the medial aspect of the knee. The ligament can be found to be tender and palpation over its attachment to the thighbone (femur) proximally, at its mid-substance, or distally over the shin bone (tibia) can be also felt. The palpation location depends on the location of injury. When force is applied to the outside aspect of the knee, the pain may be reproduced. Also, when a valgus force is applied, the inner aspect of the joint line can be palpated. Swelling over the torn ligament may also be noticed.Bruising or general swelling of the joint can also be present. In severe cases, patients may feel that the knee is unstable. Based on the severity and physical examination, MCL injury can be classified or graded on a scale of I to III.

Grade I MCL tear: In this type, the ligament is intact but stretched. The symptoms are mild.

Grade II MCL tear: It is a partial or incomplete tear. Pain is felt with valgus stress of the knee. Palpation is spotted along the medial aspect of the knee over the ligament.

Grade III MCL tear: In this case, there is complete tear of the MCL. The patientexperiences significant pain along the medial aspect of the knee. They may have difficulty in deep bending of the knee.

Diagnosis

Plain radiographs can be helpful in detecting MCL injuries. If the ligament has torn off the thigh bone, the radiograph often shows tears with a piece of bone. In case of old or recurrent injuries to the femoral side of the MCL, calcification at its origin can be seen. This is termed as “Pellegrieni-Stieda” lesion. MRI is the imaging study of choice to diagnose MCL tears.

Treatment

This injury rarely requires surgical intervention. Usually rest and anti-inflammatory medications, followed by rehabilitation, leads to cure.

Grade I injuries usually resolve without complication. They are typically managed with rest, ice, and nonsteroidal anti-inflammatory medications until the knee is pain-free to examination or routine activities. Athletes with a grade I MCL tear will be able to return to their sport within 1-2 weeks of their injury.

When a grade II MCL tear occurs, a hinged knee brace is commonly used to protect the knee from valgus forces. Athletes can often return to sports within 3-4 weeks after their injury, but may remain in a protective hinged brace with contact sports. In case of grade III injury, athletes usually require a hinged brace locked in extension and crutches for 1 to 2 weeks. As the pain resolves, the brace can be unlocked. Complete rehabilitation can range from 6 weeks to 4 months.

However, some severe Grade III MCL tears may need surgery. If surgery is required, a ligament repair with or without reconstruction with a tendon graft may be performed.

(With inputs from: www.sportsmd.com)