The knee joint is formed by three bones: femur (thigh bone), tibia (shin bone) and patella (kneecap). These bones are held together by four primary ligaments:
The collateral ligaments are found on the sides of the knee and the cruciate ligaments are inside the knee joint.
The Anterior cruciate ligament or ACL runs diagonally in the middle of the knee. It provides rotational stability to the knee and prevents the tibia from slipping out.
The most common injury to ACL is due to a sprain that causes a tear in the ligament. Sprains are graded on a severity scale depending on the amount of damage to the ligament. ACL injuries occur due to sudden jerky movements like:
The classical symptom of an ACL tear is a popping sound and a feeling that the knee will give way. This is followed by pain and swelling of the knee joint over the next 24 hours. If any strenuous activities are performed during this time, it leads to instability and further damage to the meniscus of the knee. Other symptoms of ACL tear include discomfort while walking, pain on touching the affected area and loss of full range of motion.
Most ACL injuries can be diagnosed by a thorough physical examination of the knee. Imaging tests like X-ray and MRI scans can help in confirming the diagnosis.
Treatment of ACL injuries depends on the patient’s activity level and individual needs. An athlete or anyone with an active lifestyle will most likely require surgery to regain full functioning of the knee. A less active individual may just require rest to return to a regular lifestyle. Consult expert orthopaedic doctors at our Centre for Bone & Joint for prompt care.
Research studies suggest that a non-functioning ACL due to complete tear causes damage to the knee joint, if left untreated. Therefore, it is advisable to get an ACL reconstruction surgery done at the earliest.
ACL Reconstruction Surgery is the preferred treatment for ACL tears. In this procedure, the torn ACL is replaced with a graft made of a tendon – a tissue similar to a ligament. The grafts could be from the patient (autograft) or from a tissue donor (allograft).
ACL Reconstruction Surgery is performed by an orthopaedic surgeon using an arthroscope. The graft is attached at each end to bone plugs taken from the patella and tibia, which help in anchoring the graft. The new ACL is then inserted into the femur and tibia using a guidewire and fixed there using screws. Over time, the bone plugs grow into the surrounding bone and the graft becomes a living ligament in the knee.
Physical therapy is a crucial part of rehabilitation after an ACL surgery. The success of ACL reconstructive surgery depends on the amount of physical therapy done post-surgery. The goal of rehabilitation is to reduce swelling in the knee joint, strengthen the muscles around the knees and restore full range of motion of the knee.
Studies have shown that 98% of patients recover completely and return to their earlier lifestyle. Speed of recovery varies depending on the activity level of the individual. Those with minimal physical activity can resume work within 2 weeks, while athletes are allowed to return to sports activities after 4-6 months.