The Effect of Minimalist Versus Motion Control Shoes on Patellofemoral Joint Forces in Adolescents With Patellofemoral Pain During Running: A Randomized Crossover Study

Abstract

Background: High joint forces can contribute to the pathogenesis of patellofemoral pain in adolescents. Minimalist shoes may reduce patellofemoral joint forces during running compared with commonly worn motion-control shoes. Hypothesis: Patellofemoral joint, lateral patella, and quadriceps forces will be lower, while gastrocnemius forces will be higher when adolescents run in minimalist shoes compared with motion control shoes. Study Design: Cross-sectional study; Level of evidence, 2. Methods: This within-session 2-period randomized crossover study was conducted from March 2023 to September 2024. A total of 51 physically active adolescents aged between 12 and 19 years (mean age, 16.9 ± 2 years) (23 female adolescents [45%]) with patellofemoral pain were recruited from the general population. Kinematic, kinetic, and electromyography (EMG) data were collected during overground running in minimalist and motion-control shoes, with testing randomized within the same session. Patellofemoral joint force was measured during the stance phase of running using an EMG-informed neuromusculoskeletal model. The primary outcome was the resultant patellofemoral joint force (N). Secondary outcomes included lateral patellar force (defined as the peak force acting on the patella in the frontal plane) and quadriceps and gastrocnemius muscle forces (N). All outcomes were analyzed at peak using paired t tests. Results: Compared with the motion control shoes, running in the minimalist shoes reduced peak resultant patellofemoral joint force by 7.5% (mean difference [MD], 363.2 N [95% CI, 666.8-59.5]; P = .02), reduced peak lateral patellar force by 7.8% (MD, 202.7 N [95% CI, 379-26.4]), and increased peak gastrocnemius muscle forces by 26.6% (MD, 449.3 N [95% CI, 298.6-560]). The minimalist shoe did not meaningfully alter quadriceps muscle forces compared with the motion-control shoe. Conclusion: As hypothesized, running in minimalist shoes reduced peak resultant patellofemoral joint and lateral patellar forces compared with running in motion-control shoes, while gastrocnemius forces were increased. Running in minimalist shoes did not meaningfully alter quadriceps muscle forces compared with motion-control shoes.