During ACL knee surgery, doctors generally replace a damaged ACL using tissue from various tendons in the person's leg. In some cases, the ACL can be replaced using cadaver tendons instead. Typically, the operation is performed while the individual is unconscious, but there is a way of doing it where the person stays awake for the entire procedure by injecting a numbing agent into the spinal cord. Doctors usually perform ACL surgery using tiny incisions and rely on small cameras to see what they are doing.
The anterior cruciate ligament (ACL) is a structurally crucial part of the knee that keeps it from bending forward or to the side too far, among other things. The ACL operation has changed over the years. The original version involved putting a broken ACL back together, but that didn’t work out very well, and doctors stopped doing it. Eventually, doctors discovered that taking tissue from elsewhere inside the leg and using it to replace the ACL was a more reliable solution.
The main methods for performing ACL knee surgery involve replacing the ACL with part of the patellar tendon or the hamstring. These tendons are large enough to be able to withstand losing a bit of tissue. In the case of the patellar tendon, it will usually grow back any tissue that’s lost during the operation, but the hamstring tissue is lost permanently. Doctors decide which one to harvest based on the patient’s lifestyle and other factors. The patellar tendon version of the surgery has the potential to cause patients pain while kneeling down, while the hamstring operation usually permanently weakens the leg.
Generally, doctors expect patients to do some rehabilitation work on the knee before ever having ACL knee surgery. This is because any injuries that cause an ACL tear are usually bad enough to hurt the knee in other ways, too. Doctors normally want the knee as healthy as possible when they replace the ACL, partly because it can make recovery easier.
Recovery from ACL knee surgery is measured in very different ways for different people. For example, it may only take a few weeks to reach the point where walking is easy, and for some people, that can be considered a decent level of recovery. For other people, like athletes, a more extensive recovery may be necessary. These patients often go through a prolonged and exacting rehabilitation routine to recover as much of their full athletic ability as possible without re-injuring their knees. This can take as long as six months.