The dynamic postural control of people with patellofemoral during single-leg landings: a cross-sectional study comparing people with and without pain before and after pain exacerbation

• Grant number: 24/20248-1
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: June 01, 2025
• End date: February 28, 2026
• Field of knowledge: Health Sciences - Physiotherapy and Occupational Therapy
• Principal Investigator: Fábio Mícolis de Azevedo
• Grantee: Beatriz Sanches Ferreira
• Host Institution: Faculdade de Ciências e Tecnologia (FCT). Universidade Estadual Paulista (UNESP). Campus de Presidente Prudente. Presidente Prudente , SP, Brazil

Abstract

Patellofemoral pain (PFP) is a common musculoskeletal disorder among young adults and is challenging to manage. People with this condition often report persistent pain and functional impairments, even after conservative treatment with physical therapy. In this context, investigating less explored or understood aspects, such as dynamic postural control of people with PFP, may provide relevant evidence for future clinical studies and strengthen clinical recommendations. Results from two recent systematic reviews have shown conflicting evidence about postural control impairments in people with PFP. Interestingly, although PFP is commonly exacerbated during dynamic and functional activities (e.g., squatting and hopping), few studies have focused on analyzing dynamic postural control. Moreover, among studies investigating dynamic postural control, there is a clear lack of studies including analyses during tasks with shorter reaction times, such as hop tasks. Identifying potential changes in dynamic postural control during hopping is of utmost importance due to the increased risk of other lower limb injuries and further knee pain. We will also consider investigating whether changes in postural control parameters occur concomitantly with changes in biomechanical parameters previously identified in people with PFP. Therefore, this project aims to compare dynamic postural control between people with and without PFP during ladings from single-leg horizontal hops before and after a non-invasive protocol of PFP exacerbation. Males and females aged 18 to 35 years old, with and without PFP, will be recruited. The single-leg hop task will be performed using the most affected limb in people with PFP and a randomized limb for controls. Participants will be asked to hop horizontally as far as possible, landing on a force plate. They will perform the task before and after an exercise-induced overloading protocol designed to exacerbate PFP symptoms. The landing phase of the hop task will be analyzed for postural control parameters, which will be collected using data from the force plate. Kinematics will be collected using a three-dimensional motion analysis system. The variables of interest, processed using programming software, will include parameters of the time to stabilization and center of pressure, as well as trunk, hip, knee, and ankle kinematics, and hip, knee, and ankle kinetics. Group (PFP vs. control) and condition (pre- and post-protocol) comparisons will be conducted using a repeated-measures analysis of covariance (ANCOVA), controlling for sex and body mass index. (AU)