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ACL Ligament

The first image is of the normal Anterior Cruciate Ligament (ACL). The second shows the basic steps in ACL Reconstruction. This procedure is done through the arthroscope with very small incisions.

The ACL ligament, which runs from the front of the knee to the upper back of the knee, is very important for stability and function. It is also commonly injured and may tear alone or in conjunction with cartilage damage. This ligament has been repaired for over 30 years, but for about the last 20 years, most are done with what is called "arthroscopic-aided technique." Unfortunately, it is not possible to simply sew the torn ligament back together. All ligament repair is in fact a reconstruction.

When to Repair It
In some cases of older individuals, ACL repair is not recommended. For most active patients, repair is necessary. Because it is actually a reconstruction, it is not urgent to have the surgery. In fact, multiple studies have shown that patients who have repair done immediately after the time of injury, develop stiffness and generally have poorer results. It is recommended that the injured patient attend physical therapy to restore movement and strength as well as reduce swelling before surgery is done.

What Repair to Have
There are many different reconstructions of the ACL. The tissue used to perform the repair may come from the patient or from tissue banks.

Your Own Tissue
The most common tendon material used in reconstruction of the ACL comes from the hamstrings or from the patella ligament (the ligament which attaches the patella, or kneecap, to the tibia, the shin bone).

Hamstrings
The hamstrings are easily harvested through a small incision, but individually are not strong enough for the ACL repair. They, therefore, must be folded over on themselves and sewn together. In addition, some athletes (especially jumpers) feel the loss of their hamstrings may limit their abilities. The hamstrings have more elasticity (or stretch ability) than other tendons. Thus, the knee repaired with the hamstrings may have a tendency to be slightly loose. Dr. Clyburn does not routinely use the hamstrings.

Patella Tendon
This is often called "BTB" or "bone tendon bone" because a strip of the patella ligament (which is the middle third) is harvested along with a segment of bone from the patella and from the tibia. It is then transferred into the knee where it is secured exactly where the original tendon existed. The bone is then secured with screws. This is the repair Dr. Clyburn chose for himself in 1989. The disadvantage to this procedure is that it requires a moderate incision to harvest the graft, and tenderness or pain from the site of the harvest is not uncommon. The advantage is that it is a very strong repair.

Tissue Bank Tendons
There are a number of different tendons available for ACL reconstruction from the tissue bone. Dr. Clyburn has chosen to use the patella ligament, or bone tendon bone, because of his familiarity with the technique and the excellent strength of the material. It is performed exactly as the usual BTB technique except that the patient does not have the disadvantage of pain about the donor site (the area where the graft has been taken). This is the technique he chose when his son suffered an ACL tear a couple of years ago. The disadvantage is a very slight risk of infection from the graft. Reputable graft sources use extreme caution in harvesting human tissue and test them extensively. Despite this, there have been extremely rare and isolated cases of disease transmission.