ECSS Paris 2023: OP-BM24
INTRODUCTION: Contemporary best-practice guidance recognises patellofemoral pain (PFP) as a multifactorial condition requiring clinically targeted rehabilitation rather than one-size-fits-all approaches (Neal et al., 2024). Existing studies typically focus on isolated muscles or limited biomechanical domains, restricting whole-chain interpretation of neuromechanical coordination that may characterise PFP during running conditions (Muniz, et al 2023). Therefore, this study aims to investigate the neuromechanical mechanisms in PFP during running, to inform future intervention strategies. METHODS: Seventeen runners with PFP were compared with 17 injury-free controls during overground running. Institutional ethics approval was obtained. Three-dimensional kinematics (240 Hz), ground reaction forces (1000 Hz), and surface electromyography (EMG) from lower-limb and trunk muscles were collected. EMG amplitude was normalised to maximal voluntary isometric contractions. Joint angles and moments at the ankle, knee, hip, pelvis and thorax, alongside peak muscle activation, were extracted across stance (0-40%) and terminal swing (85–100%). Between-group differences were assessed using independent t-tests with Cohen’s d and 95% confidence intervals. Subgroup effects of injury severity and kinesiophobia, within the PFP cohort were examined using one-way ANOVA and raincloud visualisation. RESULTS: Stance (0-40%) Compared with controls, the PFP group exhibited reduced peak tibialis anterior activation (38.5 ± 20.2 vs 63.2 ± 21.6 %max; p = 0.002, d = 1.18) and greater peak gluteus maximus activation compared to controls (155.3 ± 11.1 vs 96.3 ± 34.6 %max; p < 0.001, d = 2.30). No significant between-group differences were observed in sagittal-plane and frontal plane joint moments or kinematics (all p > 0.05). Terminal swing (85–100%) The PFP group demonstrated no between-group differences in knee, hip, or thoracic sagittal kinematics, joint moments, or proximal and distal muscle activation (all p > 0.05). Subgroup Analysis For all significant variables, ANOVA subgroup analyses within the PFP cohort showed no effects of symptom severity or kinesiophobia (p > 0.05), with raincloud plots demonstrating substantial overlap and no graded patterns. CONCLUSION: In stance, the PFP had a lower activation peak of TA, suggesting reduced ankle loading/control response during initial contact. Peak GMax activation was higher in PFP group suggesting greater reliance on a hip extensor strategy contributing to whole-limb support. No differences during subgroup analysis supports the idea that these PFP mechanical characteristics may be present across a broad range of clinical presentations.
Read CV Joseph LiddyECSS Paris 2023: OP-BM24