Kneecap Pain (Patellofemoral)

Patellofemoral pain, also called runner's knee, is a dull ache in the front of the knee that comes from where the kneecap rides against the groove on the end of the thighbone. When the kneecap does not glide cleanly through its groove, the cartilage on the back of it is loaded unevenly and becomes irritated. It is rarely one single problem; muscle imbalances, bone shape, alignment, and training habits usually contribute together. It is one of the most common knee complaints in active adolescents and young adults, and most people improve with the right exercise program.

Common symptoms include:

• A vague, achy pain in the front of the knee or behind the kneecap
• Pain with stairs, squatting, kneeling, or running, especially downhill
• An ache that builds while sitting with the knee bent and eases when you stand, sometimes called the movie-theater sign
• A grinding or crunching feeling when bending and straightening the knee

Patellofemoral pain is diagnosed from the history and a focused examination that checks tenderness around the kneecap, how it tracks, and hip and quadriceps strength. Imaging is not usually needed. X-rays can show the shape of the groove and the position of the kneecap, and an MRI is reserved for concern about cartilage damage or another structural problem.

Patellofemoral pain is almost always treated without surgery:

• Hip and quadriceps strengthening, the most effective treatment
• Activity changes to reduce hill running, stair climbing, and deep squatting while strength builds
• Supportive insoles for feet that roll inward
• Patellar taping or a brace to allow more comfortable rehabilitation
• An over-the-counter anti-inflammatory to settle a flare

Surgery is rarely needed. It is considered only when imaging shows a clear structural reason the kneecap does not track properly and a thorough nonsurgical program has not brought relief.

For a fuller explanation, including anatomy, diagnosis, and the full range of treatment:

• Patellofemoral Pain Syndrome — AAOS OrthoInfo