Dull pain in the front part of the knee. What is it?

A 30-year-old yogini presented with pain in the anterior (front) and posterior (back) aspect of the knee. In 2012 she was diagnosed with MS (multiple sclerosis). Until a couple of weeks ago the patient was very active, doing yoga 4 times a week, attending gymnastic classes and going to the gym.

History, physical and diagnostic tests identified the condition to be chondromalacia patella. The mechanical condition is called patellofemoral pain syndrome, indicating damage to the cartilage under the kneecap. The MRI confirmed the presence of arthritis (inflammation of the joint) in the knee, refuting MS correlation.

Symptoms of patellofemoral pain syndrome

The most common one is knee pain increases when you walk up or down stairs. Simple treatments – such as rest and ice – often help, but sometimes PT (physical therapy) or even surgery is needed to ease the pain.

More symptoms:

  • Dull, aching pain in the front of your knee, exacerbated when you:
    • Walk up or down stairs
    • Kneel or squat
    • Sit with a bent knee for long periods of time

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Fun Fact on Patellofemoral Weight Bearing with Range of Motion

Motion:                                        Weight Bearing:

5 degrees of flexion                       30% body weight

30 deg. of flex.                               2 x body weight

45 deg. of flex.                               3 x body weight

75 deg. of flex.                               6 x body weight

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A recent study published in the Journal of Orthopaedic Research shows that men display a mean unloaded patellofemoral joint contact areas of 210, 414, and 520 mm at 0 degrees, 30 degrees, and 60  degrees of knee flexion, respectively. Women unloaded contactacts were similar at 0 degrees, but significantly smaller at 30 deg. and 60 deg., with mean values of 269 and 396 mm, respectively.

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If the knee pain doesn’t improve within a few days, consult your doctor.

Dr. David Carfagno is a Board Certified Internist and Sports Physician, who trained at the Cleveland Clinic Foundation

Thomeé, R., Augustsson, J., & Karlsson, J. (1999). Patellofemoral pain syndrome. Sports medicine, 28(4), 245-262.

Petersen, W., Ellermann, A., Gösele-Koppenburg, A., Best, R., Rembitzki, I. V., Brüggemann, G. P., & Liebau, C. (2014). Patellofemoral pain syndrome. Knee Surgery, Sports Traumatology, Arthroscopy, 22(10), 2264-2274.

Besier, T. F., Draper, C. E., Gold, G. E., Beaupré, G. S., & Delp, S. L. (2005). Patellofemoral joint contact area increases with knee flexion and weight‐bearing. Journal of Orthopaedic Research, 23(2), 345-350.