Treatment of an ACL Tear:
An ACL tear is an injury to one of the four major knee ligaments. When an ACL tear occurs, the knee can become unstable, and potentially give out when the knee joint is being used. Because of this, many people who sustain an ACL tear will decide to have ACL surgery in an effort to return to their normal activities.
Timing of Surgery:
ACL reconstruction is usually not performed until several weeks after the injury. Studies have shown improved results when ACL reconstruction surgery is delayed several weeks from the time of injury. This allows the inflamed and irritated knee to cool down. Swelling decreases, inflammation subsides, and range of motion improves. Resolution of swelling and stiffness prior to ACL reconstruction surgery improves the post-operative function of the joint.
Repair or Reconstruction?:
ACL reconstruction surgery is commonly, and improperly, referred to as an "ACL repair." Unfortunately, a torn ACL cannot be repaired. Rather, the torn ligament must be entirely removed, and a new ACL must be reconstructed using other healthy tissue. It is not possible to repair the torn ACL by simply reconnecting the torn ends. The correct terminology is an ACL reconstruction, not an ACL repair.
Determining Type of Graft:
Once the decision is made to undergo ACL reconstructive surgery, the type of reconstruction must be decided. The major decision is whether to use tissue obtained from your body to create a new ACL, or to use tissue from a donor to make the new ACL. There are various pros and cons with each type of graft.
There are also newer techniques, such as the "double-bundle" ACL reconstruction, that may be offered to you. These techniques have not been shown to be more effective at getting people back to their pre-injury level of activities.
Having ACL Reconstruction Surgery:
The ACL reconstruction surgery lasts about 1 1/2 to 2 hours, depending on the graft choice and any other work that may need to be done in the knee joint. Following the procedure, you will be given crutches and may be given a knee brace. The decision to use a knee brace is controversial and can be discussed with your doctor. Some doctors also use a CPM (continuous passive motion) machine in the days following the ACL reconstruction. This is also controversial and may be discussed with your doctor.
Rehab After ACL Surgery:
Rehab is one of the most important, yet often neglected, aspects of ACL reconstruction surgery. Rehab following ACL surgery focuses on restoring motion and strength, and improving the stability of the joint to prevent future injuries.
While general guidelines exist for ACL rehab, it is critically important that each person progresses through their rehab as their knee allows. Progressing too quickly or too slowly can be detrimental to overall results from surgery, therefore it is important to ensure your therapist and physician are guiding your rehab.
Return to Sports:
More than 90% of patients are able to resume their previous level of activity after ACL reconstruction. A small percentage of patients will be limited by persistent pain or instability; however, changes in activity level following ACL reconstruction surgery are often due to personal choice rather than limitations of the knee joint.
RL Larson and M Tailon "Anterior Cruciate Ligament Insufficiency: Principles of Treatment" J. Am. Acad. Ortho. Surg., Jan 1994; 2: 26 - 35.