ABSTRACT
Objective To develop plantar force model of patellofemoral pain (PFP), so as to provide theoretical references for the assessment of PFP rehabilitation. Methods The case-control study was conducted, and a total of 126 patients with PFP and 126 healthy controls matched by gender and age were enrolled in the study. The participants were tested for plantar force and pressure during level walking, and twelve plantar regions were divided and recorded. Whether the participants suffered PFP was analyzed as dependent variable, meanwhile the peak force and peak pressure in 12 plantar regions of participants at selected speed during level walking were analyzed as independent variables. Conditional logistic regression (CLR) equations of peak force and peak pressure with PFP were established, respectively. The receiver-operating characteristic (ROC) curve of the corresponding equations was derived, and the area under ROC curve was calculated to analyzed the validity of different equations on PFP assessment. Results The CLC equation of peak force in 12 plantar regions of the participants with FFP was constructed, and only peak force of lateral heel was in the equation. The CLC equation of peak pressure in each plantar region included medial heel, midfoot, 1st and 2nd metatarsals. Meanwhile, the area under ROC curve of the pressure equation was larger than that of the force equation. Conclusions Peak force and pressure at different plantar regions can be used to assess PFP during level walking, and peak pressure is more effective for assessment.
ABSTRACT
Objective To study the sex-specific lower extremity biomechanics of amateur runners with patellofemoral pain (PFP). Methods Fifteen male and ten female amateur runners with PFP were identified and enrolled in PFP group, twenty-five healthy amateur runners matched with the PFP group were recruited as control group. The kinematics and kinetics, surface electromyography (EMG) data from all the subjects in the running task were collected.Two-way analysis of variance was performed to determine the influence of group and sex on lower extremity biomechanics during running. Results Compared with control group, male amateur runners with PFP showed a greater peak knee flexion angle during the landing phase of running. Compared with control group, male and female amateur runners with PFP showed a greater peak hip adduction angle during the landing phase of running, while the peak hip adduction angle of female participants was significantly greater than that of male participants. Conclusions Amateur runners with PFP showed sex-specific lower extremity biomechanics in the running task, and the clinical intervention for PFP should be sex-specific.