// Common injuries - medial collateral ligament

by Paul Wright

Injury to the medial collateral ligament (MCL) of the knee is a relatively common injury seen by physiotherapists and sport physicians in private practice – and it is especially common in contact sports and high speed recreational activities such as water skiing and snow skiing. However, injury can also occur during fitness activities such as boot camp and circuit events that involve rapid changes of direction.

It is vital for fitness professionals to understand the role of the knee ligaments and the impact that exercise can have on basic knee integrity, and this is especially true for clients with an injured MCL as this ligament (unlike the ACL) is rarely surgically repaired when damaged and exercise plays a vital role in the rehabilitation process.


The knee contains two separate joints, the tibiofemoral joint and the patellofemoral joint. There are four major ligaments that stabilise the tibiofemoral joint – these are the well known anterior cruciate ligament (ACL), the posterior cruciate ligament (PCL), the lateral collateral ligament (LCL) and the topic for this article – the medial collateral ligament (MCL).

The MCL originates from the medial epicondyle of the femur just above the joint line and runs down to attach to the anteromedial aspect of the tibia; there is also a connection between the MCL and the medial meniscus. The role of the MCL is to prevent lateral tilting of the tibia in relation to the femur.


The MCL is most typically injured when an excessive valgus stress is applied to the partially bent knee. As mentioned previously, this can occur during awkward falls when skiing and in contact sports such as rugby when the player is tackled from the ‘outside in’ and the medial ligament is placed under stress – especially if the foot remains wedged or locked to the ground.


MCL injuries are most commonly graded on a one to three scale depending on the severity of the injury:

Grade one (mild) – patients with a grade one MCL injury usually report local tenderness over the medial side of the knee following the injury. There is often little or no swelling, and stress-testing of the ligament in the clinic is painful, but there is not excessive laxity compared to the unaff ected leg.

Grade two (moderate)
– grade two injuries to the MCL usually present following a more severe and higher force injury. There is marked tenderness, increased swelling and most importantly there is some laxity when testing the ligament, but there remains a distinct end feel, implying the ligament is still intact. However, there has been some stretching or rupture to some of the fibres of the ligament.

Grade three (severe)
– a grade three MCL injury is the result of severe and/or high velocity valgus stress to the knee that results in complete rupture of the ligament. The patient may report increased instability and the knee even giving way with certain movements. In clinical evaluation there is tenderness over the medial side of the knee with stress-testing of the MCL showing gross laxity and no distinct end feel, indicating that the ligament is most likely completely ruptured.

Note: It is important for the health professional to realise that the higher the grade injury to the MCL, the more likely it is that there is also damage to the other ligaments and structures of the knee, thus complete investigation and assessment by a qualified medical professional is essential (see photo 1).


The overwhelming majority of MCL injuries are treated non-surgically, with even the most severe grade three injuries recovering and returning to sport equally as well as surgically managed patients. However, the exact treatment protocol needs to be discussed with the medical specialist in consultation with the physiotherapist and patient. The need for surgery may also be affected by the extent of damage to other structures such as the meniscus and cruciate ligaments.

For the typical lower grade MCL injury, the usual RICED program is prescribed in order to reduce post-injury swelling and joint stiffness. This initial stage may take from a few days up to two weeks, and can also include active range of motion exercise such as heel slides (lying supine and sliding the heel to the buttocks) and stationary cycling.

The next stage of rehabilitation includes the introduction of progressive straight line strength training activities such as step ups, lunges, one-leg press and bridging exercises (see photo 2) that allow for the damaged ligamentous fi bres to re-align and for functional strength to return. Hamstring exercises such as leg curls and pulleys can also be included at this stage. Straight line jogging and road cycling can also be added depending on the patient’s progress, range of motion and pain levels. 

The final steps in the rehabilitation process are aimed at regaining lateral stability and proprioception to allow full return to sport and exercise. Activities to be included at this stage include one-leg hops and jumps, side to side jump and lands, shuttle runs, rebounder and BOSU® control exercises – all under the guidance of the treating physiotherapist, sports physician and personal trainer. 

Click HERE to view an interactive resource that allows you to visually explore the anatomy of the knee and access information relating to common ailments and injuries.


Paul Wright, BAppSc (Physio) DipEd (PE)
Paul is the owner of Get Active Physiotherapy with clinics inside Fitness First clubs at St Leonards (Sydney) and Kotara (Newcastle) as well as a head offi ce in the CBD of St Leonards. He has produced a series of injury prevention and training DVDs for fitness professionals, including a session on knee injury rehabilitation. For more information visit www.getactivephysio.com.au or call 02 9966 9464.

NETWORK • SUMMER 2008 • PP21-22