What is Runner’s Knee?
Chondromalacia of the patella refers to the softening of the cartilage of the kneecap. The cartilage in our knees relies upon intermittent compression to squeeze out waste products and then allow nutrients to enter the cartilage from the synovial fluid of the joint. When you run, certain mechanical conditions may predispose you to a mis-tracking kneecap. Portions of the cartilage may then be under too much or too little pressure and the appropriate intermittent compression that is needed for waste removal and nutrition supply may not be present. This may result in cartilage deterioration, which at the knee usually occurs on the medial aspect or inner part of the kneecap. Pain is usually felt after sitting for a long period of time with the knees bent. Running downhill and sometimes even walking down stairs can be followed by pain.
What Causes Runner’s Knee?
Runners knee is caused by several factors, including a high quadriceps angle, wide hips (female runners), knock knees (genu valgum), subluxating patella, high patella, small medial pole of patella or corresponding portion of the femur, weak vastus medialis, and pronation of the feet. Most often, weak quadricep muscles will be the problem, as they do not absorb a sufficient amount of the impact of running, passing down the impact onto the knees. To read about weight training and how it can help strengthen your quadriceps click here.
How to Prevent or Treat Runner’s Knee
This form of knee pain is usually associated with overuse and abnormal foot pronation. Symptoms include pain along the inner aspect of the patella (knee cap), particularly during the stage of running that includes foot impact. When the problem is present on one side and not the other, causative factors may include road cant (affected knee on the high side) and limb-length inequality (affected knee on the longer limb). Self-care should include ice massage for 15 to 20 minutes twice a day until pain free; over-the-counter anti-inflammatory medications; over-the-counter arch supports; general hip-, thigh-, and leg-stretching exercises; and, if the heel counters are broken down to the inside, new shoes.
While not the most common knee injury in runners, patellar tendinitis may be among the more frequent post-Boston Marathon knee ailments. Downhill running can be an aggravating factor for patellar tendinitis as well. Symptoms include tenderness of the patellar tendon (running from the knee cap to the leg) and pain on foot impact in running. Self-care should include ice massage for 15 to 20 minutes twice a day until pain free; over-the-counter anti-inflammatory medication; new shoes (if your current shoes have significant mileage); and a general hip-, thigh-, and leg-stretching program.