ACL Reconstruction Patellar Tendon
Anterior cruciate ligament (ACL) reconstruction (patellar tendon) is a surgical procedure that replaces the torn ACL with part of the patellar tendon. The anterior cruciate ligament prevents excessive forward movement of the lower leg bone (tibia) in relation to the thigh bone (femur) as well as limiting rotational movements of the knee.
A tear of this ligament can make you feel as though your knee is unstable. Anterior cruciate ligament reconstruction is surgery to reconstruct the torn ligament with a tissue graft - in this case , the middle third of the patellar tendon.
Causes
An ACL injury most commonly occurs during sports that involve twisting or overextending your knee. The ACL can be injured in several ways:
- Sudden directional change
- Sudden slowing down while running
- Landing from a jump incorrectly
- Direct blow to the side of your knee, such as during a football tackle
Symptoms
When you injure your ACL, you might hear a loud "pop" sound and you may feel the knee buckle. Within a few hours after an ACL injury, your knee usually swells due to bleeding from the torn ligament. You may notice that the knee feels unstable or seems to give way, especially when trying to change direction on the knee.
Diagnosis
An ACL injury can be diagnosed with a thorough physical examination of the knee and diagnostic tests such as X-rays, MRI scans and arthroscopy. X-rays may be needed to rule out any fractures.
In addition, your doctor will often perform the Lachman’s test to see if the ACL is intact. During a Lachman test, knees with a torn ACL may show increased forward movement of the tibia and a soft or mushy endpoint compared to a healthy knee.
The pivot shift test is another test to assess ACL tear. During the pivot shift test, if the ACL is torn the tibia will move forward when the knee is completely straight and as the knee bends past 30° the tibia shifts back into correct place in relation to the femur.
Procedure
The goal of ACL reconstruction surgery is to restore stability to your knee.
Anterior cruciate ligament reconstruction patellar tendon is a surgical procedure to replace the torn ACL with part of the patellar tendon taken from the patient’s same leg. The new ACL is harvested from the patellar tendon that connects the bottom of the kneecap (patella) to the top of the shinbone (tibia). The procedure is performed under general anaesthesia. Your surgeon will make two small cuts about ¼ inch around your knee. An arthroscope, a tube with a small video camera on the end is inserted through one incision to see the inside of the knee joint. Along with the arthroscope, a sterile solution is pumped into the knee to expand it providing the surgeon a clear view of the inside of the joint. The torn ACL will be removed and the pathway for the new ACL is prepared. Your surgeon makes an incision over the patellar tendon and takes out the middle third of the patellar tendon, along with small plugs of bone on each end. The remaining portions of the patellar tendon on either side of the graft are sutured back after its removal. Then the incision is closed. The arthroscope is reinserted into the knee joint through one of the small incisions. Small holes are drilled into the upper and lower leg bones where these bones come together at the knee joint. The holes form tunnels in your bone to accept the new graft. Then the graft is pulled through the predrilled holes in the tibia and femur. The new tendon is then fixed into the bone with screws to hold it into place while the ligament heals onto the bone. The incisions are then closed with sutures and a dressing is applied.
Risks and complications
Possible risks and complications associated with ACL reconstruction with patellar tendon method include:
- Numbness around the incisions
- Infection
- Blood clots (Deep vein thrombosis)
- Nerve and blood vessel damage
- Failure of the graft
- Loosening of the graft
- Decreased range of motion
- Crepitus (crackling or grating feeling of the kneecap)
- Pain in the knee
- Repeat injury to the graft
Post-operative care
Following surgery rehabilitation begins immediately. A physiotherapist will teach you specific exercises to strengthen your leg and restore knee movement. Avoid competitive sports for up to 12 months to allow the new graft to incorporate into the knee joint.
Anterior cruciate ligament reconstruction is a very common and successful procedure. It is usually indicated in patients who desire to return to an active lifestyle especially those wishing to play sports involving running and twisting.
