Powers CM, Ward SR, Chen YJ, Chan LD, Terk MR.
Although several studies have demonstrated decreases in
patellofemoral pain (PFP) with the application of bracing, the mechanism by which
bracing reduces symptoms has not been elucidated.
Individuals who responded favorably to bracing will exhibit decreased
patellofemoral stress during level walking.
Repeated measures, cross-sectional.
Fifteen subjects with a diagnosis of PFP completed two phases of data
collection: 1) MRI assessment of patellofemoral contact area and 2) gait
analysis. Data were obtained under braced and nonbraced conditions. Variables
obtained from both data collection sessions were used as input variables into a
mathematical model to quantify patellofemoral stress.
Subjects reported a 56% reduction in pain following bracing. Bracing
significantly reduced peak stress during free and fast walking (17% and 27%,
respectively). The decrease in stress was the result of increased contact area as
patellofemoral joint reaction forces were increased following bracing.
Bracing resulted in a larger increase in patellofemoral contact area
than the increase in joint reaction force, resulting in a decrease in joint
The results of this study suggest a possible mechanism by
which bracing may be effective in reducing PFP and provides experimental support
for the use of this treatment method.
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