An ACL injury occurs when the anterior cruciate ligament becomes damaged through either a pull, twist, tear or other disruption of the knee. ACL injuries usually occur during athletic activities and are common in running, jumping or during sudden twisting, turning or stopping movements. An injured ACL reduces stability in the knee and decreases support of the knee joint during athletic activity.
Injuries can vary in severity, ranging from a minor sprain to a complete tear or rupture of the ligament. Less serious injuries are frequently treatable with physical therapy alone, while a torn ligament will usually require surgery, as a completely torn ligament cannot repair or reattach itself.
Signs and Symptoms of an ACL Injury
- Considerable pain in the knee that does not go away within the first few hours after the injury.
- Immediate (usually within 24 hours) swelling of the knee.
- A feeling of unsteadiness and a tendency for the knee to “give-way,” or an inability to bear weight on the injured leg.
- An audible “pop” or the perception of something snapping or breaking at the moment of injury.
- A feeling of “fullness or tightness” in the knee.
When Surgery is Needed
Arthroscopic ACL Reconstruction greatly reduces the “invasiveness” of surgery; it allows a surgeon to make only a few small incisions instead of one large incision – as is common with open procedures. A reduction in surgical invasiveness is helpful for many reasons, one of which is the improvement in recovery time after surgery.
During surgery, the ACL is replaced with quadrupled semi-tendinosus/gracilis tendons located on the side of the knee. A synthetic screw or anchoring device is utilized to fasten the replacement ligament to the femur. This is placed under arthroscopic control. The tibial end of the graft is usually anchored to the bone by a metal staple or screw. In addition, a screw is placed next to the graft within the tibial tunnel that has been drilled in the bone. This screw, known as a bio-absorbable interference screw, pushes the graft firmly against the inside of the bone tunnel to assist in the healing process. The screw is made of a material that gradually dissolves after the healing process is complete, and is eventually replaced by bone.
Expectations of Recovery
- With proper care, most patients can expect a full recovery from an injured ACL.
- Patients are able to walk on a surgically treated ACL immediately following surgery, although knee bracing is required.
- Patients who undego Arthroscopic ACL Reconstruction surgery, are likely to return to previous levels of athletic activity with proper rehabilitation and physical therapy.