When an ACL injury occurs, individuals should:
- Stop their activity immediately
- Implement the RICE principle as quickly as possible: Rest, Ice, Compression, and Elevation of the knee. More on RICE.
- Seek medical attention as soon as possible
Only a physician or sports medicine specialist can evaluate the knee injury to make a diagnosis of a torn ACL, as well as determine whether there are any additional injuries. The doctor may order x-rays or an MRI (magnetic resonance imaging) scan to make a final diagnosis.
In most cases, an ACL tear requires surgery. The decision to perform surgery on a torn ACL depends on several factors, such as the patient’s age, lifestyle, involvement in sports, occupation, the degree of knee instability, and if the patient has any other associated injuries. If the doctor and the patient decide surgery is necessary, a pre-surgery rehab program is often developed so the individual can strength the knee and reduce the swelling before surgery. Pre-surgery rehab will also help the recovery process.
During ACL surgery, the surgeon can either repair or reconstruct the torn ACL. Since ACL repair is rarely possible or effective by stitching up the tear or reattaching the detached ligament to the bone, ACL reconstruction is the best solution. ACL reconstruction is performed far more often than an ACL repair—more than 50,000 surgeries per year—and it can be achieved using one of several techniques: patellar tendon graft procedure, a hamstring graft procedure, or an allograft procedure.
In all of these cases, the ACL ligament is reconstructed by substituting a new ligament from another part of the body for the damaged one. The two most popular approaches are substituting a patella tendon or a hamstring muscle tendon. Regardless of which graft is selected by the surgeon, each one requires a special harvesting technique and different ways to attach the graft to the femur, although all ACL reconstruction is done arthroscopically, as explained below.
Knee arthroscopy is an effective reconstructive surgical technique for individuals who have a torn ACL. The technique involves placing a graft to replace the torn ACL and can be done under local, regional, or general anesthesia; this is a choice to be made between a patient and his or her surgeon. Knee arthroscopy for an ACL injury involves making two or three small incisions in the knee area. An orthopedic surgeon then inserts the arthroscope (a small camera device about the size of a pencil) into the knee joint. The arthroscope transmits images to a monitor, which the surgeon uses to identify the damage to the knee joint and the ACL.
A saline solution is pumped into the knee joint through a tube so the surgical area is clear. The surgeon removes pieces of the torn ACL and prepares the surface where the ACL normally attaches to the femur. A tunnel is drilled through the bone so the graft can be placed in the center of the knee exactly where the original ACL had been. The graft can be harvested from a tendon in the patient or from a cadaver. The graft is threaded through the tunnel and fixed into place. After the graft has been secured and the surgeon has repaired any additional damage, the incisions are closed and a sterile dressing covers the knee.
Knee arthroscopy to repair a torn ACL generally can take 15 minutes to three hours or more, depending on the extent of the damage. After surgery, patients begin to use a continuous passive motion device up to 23 hours per day and then while sleeping for the first several weeks. Patients can place partial weight on the treated leg by using crutches for the first 7 to 10 days. Supervised physical therapy is usually started on the second to third day after surgery.Along with a specially designed exercise program, ACL rehab can include use of knee support, such as a hinged knee brace, a stabilized knee support, or more basic knee supports, which are less protective. A hinged knee brace provides the best support, but they tend to be more bulky than a stabilized knee support.
The length of ACL recovery depends mainly on rehab. For an athlete with a torn ACL, some therapists and surgeons advocate an accelerated rehab program, which can return the athlete to full competition within six months. Others prefer a nine-month ACL rehab program.