What are the ligaments in the knee that are prone to injury?
ACL - Anterior Cruciate Ligament is one of the two major ligaments in the knee. It connects the thighbone to the shinbone in the knee. ACL injuries are a common cause of disability to the knee.
PCL - Posterior Cruciate Ligament is the second major ligament in the knee connecting the thighbone to the shinbone in the knee.
MCL- Medial Collateral Ligament connects the thighbone to the shinbone on the medial or inner side of the knee.
LCL - Lateral Collateral Ligament onnects the thighbone to the fibula, the smaller bone of the lower leg, which is found on the lateral or outer side of the knee.
What is the role of the ACL?
Ligaments connects a bone to another bone (across a joint). Without ligaments to stabilise the knee, the joint would be unstable and prone to dislocation.
The ACL prevents the tibia (shin bone) from sliding too far forward.
The ACL also contributes stability to other movements at the joint including the angulation and rotation at the knee joint. The ACL performs these functions by attaching to the femur on one end, and to the tibia on the other.
Types of ACL/ ligamentous injuries
Ligament injury is classified as a grade I, II, or III sprain.
Grade I Sprain:
The fibres of the ligament are stretched, but there is no tear.
There is a little tenderness and swelling.
The knee does not feel unstable or give out during activity.
Grade II Sprain:
The fibres of the ligament are partially torn or incomplete tear with haemorrhage.
There is a little tenderness and moderate swelling with some loss of function.
The joint may feel unstable or give out during activity.
Grade III Sprain:
The fibres of the ligament are completely torn (ruptured); the ligament itself is torn completely into two parts.
There is tenderness, but limited pain, especially when compared to the seriousness of the injury.
There may be a little swelling or a lot of swelling.
The ligament cannot control knee movements. The knee feels unstable or gives out at certain times.
Treatment options for ACL injuries
If the ACL is sprained but the knee shows no signs of instability, rest and physiotherapy rehabilitation may be enough. But for ACL tears in active people, athletes, and young adults, surgery is usually recommended.
Most ACL surgeries are arthroscopic (keyhole surgeries), and are mostly done as a day surgery. A graft is usually taken from a tendon elsewhere in the body, such as the hamstring. Recovery time after surgery is typically between 9months-1year with proper rehabilitative exercises. If the surgical option is not pursued, the injury will be treated through rehabilitative exercises under the guidance of a physiotherapist for 3-6months.
Regardless of whether the surgical option is chosen or not, physiotherapy is crucial to recovering from an ACL injury. While 81% of people can return to sports after an ACL injury, only 55% of them return to their previous levels, due to inadequate rehabilitation. Therefore, if you have an ACL injury, be sure to commit fully to the rehabilitative exercises, as failure to do so will greatly reduce your chances of making a full recovery.