These first-aid tips will reduce swelling and pain. During arthroscopy, your doctor inserts surgical tools through one or more small cuts (incisions) in the knee to look at the inside of the knee. An MRI can show damage to ligaments, tendons, muscles, and knee cartilage. Or you may need other imaging tests, such as an MRI. You may need X-rays, which can show damage to the knee bones. The doctor may ask: How did you injure your knee? Have you had any other knee injuries? Your doctor will check for stability, movement, and tenderness in both the injured and uninjured knee. Your doctor can tell whether you have an ACL injury by asking questions about your past health and examining your knee. This can happen when an ACL injury is not treated. The main symptom of chronic ACL deficiency is the knee buckling or giving out, sometimes with pain and swelling. The knee feeling unstable, buckling, or giving out.Īfter an acute injury, you will probably have to stop whatever you are doing because of the pain, but you may be able to walk.Limited knee movement because of pain or swelling or both.Swelling that occurs suddenly is usually a sign of a serious knee injury. This may be a sign of bleeding inside the knee joint. The knee swelling within the first few hours of the injury.Pain on the outside and back of the knee.Feeling or hearing a pop in the knee at the time of injury.So a tear happens more easily in people older than age 40. Like any other body part, the ACL becomes weaker with age.
Falling off a ladder or missing a step on a staircase are other likely causes. This type of injury is common in soccer, skiing, football, and other sports with lots of stop-and-go movements, jumping, or weaving. This can happen when you are changing direction rapidly, slowing down when running, or landing from a jump. The injury can happen when your foot is firmly planted on the ground and a sudden force hits your knee while your leg is straight or slightly bent.
Contact (being hit by another person or object) also can cause an ACL injury.Īn ACL injury often occurs during sports.
The chance of injury is higher if more than one of these movements occurs at the same time. Your ACL can be injured if your knee joint is bent backward, twisted, or bent side to side. This includes cartilage such as the menisci, or bones in the knee joint, which can be broken. Sometimes other knee ligaments or parts of the knee are also injured. The abnormal bone movement can also damage the tissue ( cartilage) that covers the ends of the bones and can trap and tear the pads ( menisci) that cushion the knee joints. Without treatment, the injured ACL is less able to control knee movement, and the bones are more likely to rub against each other. Injuries range from mild, such as a small tear, to severe, such as when the ligament tears completely or when the ligament and part of the bone separate from the rest of the bone. Topic Overview What is an anterior cruciate ligament (ACL) injury?Īn anterior cruciate ligament, or ACL, injury is a tear in one of the knee ligaments that joins the upper leg bone with the lower leg bone.