Diversity Outside In · Diversity Outside In: A new era in musculoskeletal modelling by integrating in-vivo parameters to reflect human heterogeneity.

Musculoskeletal disorders, affecting muscles, bones, joints, and associated tissues, are the leading cause of disability worldwide today. To guide professionals in preventing and treating musculoskeletal disorders, musculoskeletal models serve as powerful tools. Given that these disorders present differently between sexes and throughout the lifespan, it is crucial to include model parameters that reflect this diversity. However, while it is widely recognized in medicine and science that women and men are not simply scaled versions of one another, the field of biomechanics still relies on linear scaling of musculoskeletal models based on male bone geometry and mixed-sex muscle parameters. Datasets or models capturing the relationship of model parameters across sex, age, and genetic background are lacking, leading to incorrect personalized models. I propose to develop an innovative methodology for rapidly generating accurate, personalized musculoskeletal models that account for age and sex-specific variations. To this end, I will pioneer a highly challenging and unique experimental setup and collect data that spans both demographic factors and multiple levels of model parameters from in-vivo measurements in a population study. With this, I will develop the first musculoskeletal models in which age and sex differences are accurately represented. I propose a morphometric scaling technique, which is a novel approach, integrating full-body shape data with demographic information, to enable rapid and accessible generation of these accurate personalized models. This will set a new standard for both practical applications and research settings. Finally, these models will be used in simulations to explore how age- and sex-related differences impact musculoskeletal loading during movement. Understanding how age-sex differences affect movement and musculoskeletal loading, will guide the design of equitable rehabilitation, physical labour, prevention, and performance program.