Article

OBJECTIVE: To determine whether individuals with patellofemoral pain (PFP)
demonstrate elevated patellofemoral joint (PFJ) stress compared with pain-free
controls during free and fast walking. DESIGN: A cross-sectional study utilizing
an experimental and a control group. Although the cause of PFJ
pathology is believed to be related to elevated joint stress (force per unit
area), this hypothesis has not been adequately tested and causative mechanisms
have not been clearly defined. METHODS: Ten subjects with a diagnosis of PFP and
10 subjects without pain participated. All subjects completed two phases of data
collection: 1) magnetic resonance imaging (MRI) assessment to determine PFJ
contact area and 2) comprehensive gait analysis during self-selected free and
fast walking velocities. Data obtained from both phases were required as input
variables into a biomechanical model to quantify PFJ stress. RESULTS: On the
average, PFJ stress was significantly greater in subjects with PFP compared with
control subjects during level walking. The observed increase in PFJ stress in the
PFP group was attributed to a significant reduction in PFJ contact area, as the
PFJ reaction forces were similar between groups. CONCLUSION: Our results are
consistent with the hypothesis that increased patellofemoral joint stress may be
a predisposing factor with respect to development of PFP. Clinically, these
findings indicate that treatments designed to increase the area of contact
between the patella and the femur may be beneficial in reducing the PFJ stress
during functional activities. Patellofemoral pain affects about 25% of
the population, yet its etiology is unknown. Knowledge of the biomechanical
factors contributing to patellofemoral joint pain may improve treatment
techniques and guide development of prevention strategies.

Langue : ANGLAIS

Tiré à part : OUI