In this months edition of Journal of Orthopedic and Sports Physical Therapy, Lankhorst et al performed a systematic review to examine which variables are correlated with the developement of patellofemoral pain syndrome (PFPS). PFPS is the most diagnosed condition of the knee in patients < 50 years old and its cause is thought to be multi-factorial. Past research has suggested that PFPS may be due to delayed onset timing of vasti muscles, structural abnormalities, muscle strength and kinematic variables, however, much of the conducted research has conflicting results as well as poor research design.
This study was performed to assess what we really know to be risk factors for this condition. Over 170 papers made it past the authors “title” screen, but when assessed for quality, only 7 made the cut. Out of these 7 papers, it appears that there are only two risk factors that have a positive predictive value for the development of PFPS. These include:
- Female Gender
- Having weak knee extensor strength (male and female)
Sorry ladies. This study indicates that there is still alot that we need to learn about this condition. I would be interested to examine the role of psychological variables on the influence of this pain. What do you think?
Lankhorst NE, Bierma-Zeinstra SMA, et al. Risk factors for patellofemoral pain syndrome JOSPT 2012: 42; 81-94.