A dislocated kneecap in teenage athletes is common and may need surgery to repair

Q. My son is 15 and a year ago, he dislocated his right kneecap. He was treated with a brace for four weeks followed by physical therapy.

My son returned to all sports without limitations until last week. While playing soccer, his kneecap popped out of place again. He had X-rays and an MRI scan that showed he tore a ligament. The doctor says he needs surgery to be able to return to sports. Does this sound right? I’m concerned about him undergoing surgery.

A. Kneecap issues are very common in young athletes. Most kneecap injuries, also known as patella injuries, are caused by overuse and can be treated with rehab aimed at restoring normal quadriceps’ muscle balance and normal patella positioning.

However, when the kneecap dislocates, it is common to tear the medial patella femoral ligament (MPFL) that stabilizes the kneecap while it rides over the end of the thigh bone or femur. When the kneecap pops out of place and then back into place, it is also common to damage the patella cartilage and even break off pieces of the cartilage or bone.

If the MRI shows no cartilage or bone damage, a rehab program is effective about half of the time. In your son’s situation, the dislocation has happened a second time and is likely to occur again without surgery.

Surgery involves inspecting the joint to repair any cartilage damage and remove any loose pieces. The next step is to reconstruct the torn MPFL. After surgery, a post-op brace is used for several weeks followed by physical therapy.

There is a good success rate with surgery but most athletes are out of sports at least six months. If you are not comfortable with the plan, your son may want to get a second opinion.