Ligaments are connective tissue structures which attach from bone to bone across joints and provide passive stability. Ligaments also play an important role in balance, they contain very small cells called proprioceptors, which communicate with your central nervous system (or your brain) what position the joint is in, and also if the joint is moving or not.
The knee has four ligaments, the Anterior Cruciate (ACL), Posterior Cruciate (PCL), Medial Collateral ligament (MCL) and Lateral collateral ligament (LCL), all of which can be injured but most commonly injured are the ACL and MCL. Injury often occurs when the knee is twisted with the foot in contact with the floor for example from a tackle in rugby or football or when skiing.
There are different severities of injury:
- Grade 1 is a stretch of the ligament without tearing.
- Grade 2 is a partial tear of the ligament.
- Grade 3 is a complete tear of the ligament.
You may feel or hear a popping or feel a snapping sensation at the time of the injury. You may be unable to stand with weight on the affected leg or it may feel unstable. The symptoms for most ligament injuries will be similar, no matter which one has been damaged. These may include:
- Pain (in grade I and grade II tears)
- Swelling (possible in all three grades of injury)
- Instability (in grade II or III injuries)
Management of ligament injuries
In the first few days after injury the treatment is the same for all degrees of ligament injury. The PRICE principle is applied
It is advisable to see a Physiotherapist at this point who will assess your knee and recommend what further treatment is required.
It is not always evident how bad the injury is at this early stage, however, if a full rupture of the ligament is suspected, onwards referral to an orthopaedic consultant maybe is appropriate. Occasionally surgical repair is required.
Once the pain and swelling has started to reduce then rehabilitation of your knee can begin.
In the first two weeks rehabilitation focuses on restoring range of movement at the knee, eliminating swelling, regaining muscle power and returning to a normal walking pattern (in a mild injury).
Depending on the degree of the strain to the ligament, over the next few weeks, Physiotherapy focuses on building strength, restoring normal balance and proprioception and returning to normal daily activities.
Healing time for ligaments can vary but for a mild injury a minimum of 2 weeks out of normal sporting activities is recommended and for a more severe strain up to 3 months. It is important not to return to any strenuous or sporting activities until you have regained full strength, range of movement and balance.