Method
Twelve female subjects with unilateral PFP formed the patient group and thirty asymptomatic females formed the control group. They had their 2D frontal plane projection angle (FPPA) assessed during single leg squatting (SLS) and hop landing (SLL) tasks.
Results
In the asymptomatic control group the mean FPPA for SLS was 8.4 ± 5.1° and SLL had a mean FPPA of 13.5 ± 5.7°. In the PFP group the mean FPPA for SLS was 16.8 ± 5.4° and SLL had a mean FPPA of 21.7 +/− 3.6°, these differences were significant (p < 0.01) for both tasks.
Conclusion
Patients with PFP have a greater degree of knee valgus on unilateral limb loading task than either their contralateral asymptomatic limb or an asymptomatic control group. If not corrected this may lead to further PFJ stress and ongoing morbidity.