The Anterior Cruciate Ligament (ACL) is a crucial ligament for the knee and is important the stability of the knee. Located in the knee, the ligament starts from the posterior aspect of the femur and crosses over to connect to the anterior aspect of the tibia.
What makes the ligament so important is the function of the ACL. During movement of the leg the ACL stabilises the tibia, preventing any forward movement (anterior translation) of the tibia. Without an ACL the lower leg lacks the support necessary for most functional activities of the knee.
Apart from the lack of stability due to an ACL injury, the inability for the ligament to repair makes this type of injury more significant. Areas of decrease vascularity and presence of cartilage tissue contribute to poor healing of ACL injuries.
An ACL injury can occur in many different ways, and though often associated with athletes and sport this injury can happen to anyone. Mechanisms for an ACL injury include suddenly changing direction or pivoting with your foot firmly planted on the ground. Twisting and hyperextending the knee will increase the susceptibility. Landing awkwardly or an impact like a motor vehicle accident can also cause an ACL injury.
While many immediately think surgery once they have sustained an ACL injury, conservative treatment can also be a viable option. Further details can be seen in the conservative ACL injury article. While many settle on a procedure to repair the damaged ACL, the date of surgery can be prolonged which makes conservative treatment important immediately following the injury. Prehabilitation, known also as prehab, is vital and can significantly reduce complications post-surgery.
Surgical treatment for an ACL often uses an autograft technique, where a tendon from another part of the body is used as a new ACL. The graft is taken from either the patella tendon or the tendon of one of the hamstring muscles, and used taken from the same leg as the ACL injury. The tendon is then surgically positioned in the same place as the old ACL and this encourages the growth of a new ligament.
Recently a new surgical method has been developed known as the LARS (ligament augmentation and reconstruction system) procedure. The difference with the LARS procedure is the use of a synthetic graft (allograft) that encourages ACL growth. While not overly new or revolutionary, this procedure has grown in popularity due to the considerably shorten rehabilitation process. However the LARS procedure does have some shortcomings. The graft is seen as less flexible and pliable, and is not an option for every ACL injury. Long term outcomes of the LARS procedure are unknown which includes not knowing the long term success rates of this procedure.
Regardless of your priorities post ACL procedure, the vast majority of the rehabilitation process will be the same. The stages are broadly outlined below:
0 – 6 weeks:
Patient education regarding walking with crutches and what to avoid during the early stages. Aim is to regain near full range of movement of the knee, while helping with pain and oedema management. Strengthening is started with Closed Kinetic Chain (CKC) exercises and simple proprioception exercises.
6 – 12 weeks:
Often seen an important stage as at this point the ACL graft is at its weakest. Aim is to have gained full range of movement and progressed cardio fitness. Strengthening exercises continue to be CKC though are progressed to have more load applied to the knee. Proprioception exercises are progressed to include a change is surface like a trampoline, eliminating any visual feedback by closing eyes, and providing external stimulus like arm movements.
12 – 16 weeks:
Building on the early stages, strengthen and stability are progressed. Often includes attending a gym, sport specific exercises and fitness, and also Open Kinetic Chain (OKC) exercises. During this stage a patient should have returned back to work.
The final stage which is especially important for athletes returning to sport. Sport specific exercises and fitness training is progress with introduction of plyometrics, dynamic exercises. These include explosive movements like box jumps both forward/backwards and laterally, and progressed onto single box jumps. Jumping lunges is another good plyometric exercise for ACL rehabilitation. Sport specific movements can also be replicated through plyometrics.
Surgical rehabilitation of an ACL injury often have set guidelines for every stage, with differences in the rehabilitation dependent on your final outcome, like a return to sport. A reconstructed ACL will require a lifelong commitment to maintain strength and stability, especially if you are aiming to live an active life.
For more information, or to book an appointment to have our physio team help you get back to fitness and health, talk to your friendly Gold Coast Physio today on (07) 5574 4303!