The Anterior Cruciate Ligament (ACL) is a tough band of tissue connecting the femur (thigh bone) to the tibia (shin bone).
It runs diagonally through the inside of the knees and gives the knee joint stability. The ACL is one of the most important ligaments within the knee.
The ACL is a commonly injured knee ligament. If it is torn the knee will become very unstable and lose its full range of movement.
Causes of injury:
- Landing incorrectly from a jump
- Stopping suddenly
- Changing direction quickly
Following an injury a loud popping noise
- Immediate swelling of the knee
- Pain and wobbliness in the knee
- Instability within the knee
- Giving way or collapsing of the knee
- MRI scan
Treatment will depend on the nature of the injury and the ligaments affected.
The first method of treatment for ACL injury is to have physiotherapy to help rehabilitate the injury. Low impact sports such as swimming are recommended to keep the leg moving.
If the knee remains unstable then ligament reconstruction surgery is suggested.
A torn ACL cannot be repaired by stitching it together. It has to be reconstructed by attaching new tissue to it.
This is performed through keyhole surgery where a tendon from elsewhere in the body is used to replace the ACL. This can either be the hamstring tendons of the patient or a piece of tissue taken from the patellar tendon or part of the quadriceps tendon.
The operation usually takes between an hour and an hour and a half and usually requires an overnight stay in the hospital.
Following ACL repair patients will be in a knee brace and on crutches for between two and six weeks.
Rehabilitation can take several months to improve the strength of the quadriceps, gluteal and hamstring muscles.
Physiotherapy and intense exercises will be needed to build the strength of the knee and to increase movement and flexibility.
Within six to nine months the patient should be able to return to contact sports.