The review will be guided by the following research question: What is the role of PA on the trajectory from intra-articular knee injury to PTOA in young men and women? As PTOA is a joint condition with a ‘disease’ component and an ‘illness’ component,24 (link) we will only describe the association between PA, and the factors PA underpins, with PTOA disease in this review. Disease will be defined as: ‘abnormalities of the structure and function of body organs and systems that can be specifically identified and described by reference to certain biological, chemical or other evidence’.103 (link) Additionally, we will only include studies working with young participants (average age of study population at study start or follow-up measurement is 18–40 years old) in this review. Within the research question, the following themes have been identified a priori: PA, systemic inflammation, knee joint load, adiposity, strength (lower body), intra-muscular adipose tissue (lower body), muscle size (lower body), and bone mineral content. For this review, we will use consensus definitions for intra-articular knee injury, PA, the themes underpinned by PA, and PTOA (table 1 ). If there is no agreed or clear definition, then best practices used by previous literature or consensus among the research team will be adopted.
Free full text: Click here
