What is a Medial Collateral Ligament (MCL) Injury of the Knee?
By Laurence APAM
What is the MCL?
The MCL stands for Medial Collateral Ligament. The MCL
does not solely exist in the knee as other areas of the body also have an MCL,
e.g. the elbow. Medial refers to the inside part of the body, collateral
meaning an accessory part and ligament being a strong connective tissue. The
MCL attaches from the inside of the femur, running along the knee and attaches
on the medial aspect of the tibia. The MCL is one of four knee ligaments that
are critical in maintaining support of the knee.
What injury can occur to the MCL?
MCL injury can include a stretch, partial tear or
complete tear of the ligament on the inside of the knee. Other injuries that
may masquerade as a MCL injury include medial meniscus, ACL tear, patella
dislocation, tibial plateau fracture, medial knee contusion (bruise).
How do injuries to the MCL occur?
MCL injuries are one of the most common injuries of the
knee. It occurs when a valgus force causing the ligament to stretch beyond its
structural capabilities. A valgus force is one that pushes the outside of the
knee inwards, causing a stretching of the medial structures. Generally, this
occurs from impact, or when the lower leg is in contact in the ground and
unable to move. A combined movement of flexion/valgus/external rotation is the
main mechanism of injury to the MCL.
What are the Symptoms of an MCL injury?
MCL knee injuries are graded on a 1 to 3 scale, with 3 being a complete rupture of the ligament. Depending on the degree of injury will determine the presentation of the condition.
Grade 1: Mild medial knee pain, mild swelling, possible limp and tenderness on palpation of MCL ligament.
Grade 2: Moderate medial knee pain, moderate swelling, limping and instability.
Grade 3: Severe medial knee
pain, heavy swelling and knee gives way under valgus force.
What is the management for injuries to the MCL?
Initially, it is important to determine the extent of the injury. In more severe cases of knee trauma, the MCL along with other structures will also be injured. For example, if a complete rupture of the MCL ligament has occurred (grade 3), it is extremely likely there is damage to a surrounding ligament or knee cartilage. ACL and other knee ligaments should be screened after any suspected MCL injury.
Majority of MCL injuries can be treated non-operatively, requiring physical therapy for a period of weeks. However, for grade 3 ruptures, it is likely to require surgery. In the initial phases of rehabilitation, you will want to:
Activate quadriceps muscle, particularly VMO.
- Restore range of motion as early as possible.
A comprehensive rehabilitation program is critical during
recovery. This will include the ability to control the knee and regain strength
in the surrounding structures. This will take anywhere from 2 – 12 weeks for
majority of cases.
Can MCL injuries be prevented?
Yes, to a certain extent. During contact sports it is sometimes impossible to avoid injury when unexpected forces interact with the knee. However, there are ways to significantly reduce the likelihood of the knee being in a dangerous situation, for both contact and non-contact sports.
- Appropriate neuro-muscular warm up – control/proprioception exercises. This includes single leg landing and explosive change of direction.
- Strengthening and control programs – building up strength and control in lower limb and trunk to ensure proper alignment and reduce the risk of the knee being in a poor position.