What are ACL injuries?
Your anterior cruciate ligament (ACL) connects the long bone of your thigh — your femur — with your shinbone — your tibia. Anterior refers to the ligament’s forward position among a group of ligaments that form an “x” (the cruciate part of the name) inside your knee joint and control the back and forth action of your knee. The ACL itself holds the tibia in place, preventing it from sliding out in front of the thighbone; it also makes sure your knee remains stable when it rotating. One of the most common causes of knee pain, injuries to your ACL can include sprains, stretches, partial tears, and complete tears.
If you hear or feel a “popping” sensation in your knee, have your knee give out from under you, and experience knee swelling as well, it’s possible that you’ve damaged your ACL.
Your knee may also lose its range of motion, and you may feel tenderness in the joint. Walking may be painful or uncomfortable.
Suddenly stopping or changing direction can injure your ACL, as can landing from a jump incorrectly or slowing down too fast when you are running. Think of the ACL as a flexible fence guarding the intersection of the joint: these kinds of sudden actions use a lot of forceful pressure, and that pressure can break through the fence. ACL injuries are especially common among athletes who participate in sports such as soccer, football, and basketball that rely on these kinds of quick-adjustment movements. Female athletes are more susceptible to these kinds of injuries than men are; the proposed reasons are differences in pelvis and leg alignment and ligament tension.
“Because ACL injuries are so common, sports medicine practitioners in particular are familiar with their many presentations,” says William Sayde, MD, an orthopedic physician at OINJ. “The first thing a doctor will do is take a medical history, find out when the injury occurred, and do a physical exam. Your injured knee will be compared to your healthy knee, and an MRI might be required to see the extent of the damage, or to see if there is other tissue involved. An X-ray might be done to rule out bone involvement. We would also need to see the extent of the damage, which can range from a simple sprain, or stretch, of the ACL to a full tear, which completely destabilizes the knee.”
“Treatment options have a range that corresponds to the degree of the injury and your level of activity, with the goals of stabilizing and strengthening your knee so it can bear the level of activity that will be required of it. A tear will not heal itself without surgery, but rest, bracing, and physical therapy would probably suffice for a non-athlete with a minor sprain. If you have a complete tear and you are an athlete, surgery will most likely be required,” says Rehan Shamim, MD, another orthopedic physician at OINJ. “During the procedure, your surgeon would reconstruct your ligament, which is now generally done with arthroscopic surgery. This minimally invasive procedure means less pain and shorter recovery time. However, don’t expect to be back on the playing field right away; the ligament would have to regrow, and physical therapy will be required along the way.”