Patellofemoral morphology influences muscle activation and patella translation

Patella kinematics such as lateral tilt and translation may be associated with patellofemoral pain and osteoarthritis development. Physiotherapists design programs to strengthen the VMO to decrease tracking and tilt to reduce contact pressure. Using a musculoskeletal model, we estimated in vivo joint loading for a range of joint geometries. We hypothesized that the model would increase VMO activation for shallow trochlear grooves. However, we found that the shallow groove decreased VMO activation and increased lateral patella translation. This suggests that VMO strengthening may translate the patella medially and increase contact pressure in people with shallow trochlear grooves.