Exploring how to implement a knee injury prevention program for young people playing sports in the UK: a mixed methods study

Background Common school sports in the UK, such as football, rugby, netball and basketball, that involve sudden change of direction, jumping and landing are high-risk for anterior cruciate ligament (ACL) injuries.

A recent national database study found that there has been a twenty-nine-fold (2800%) increase in the numbers of ACL reconstructions that have been performed in the UK in children and young people (aged 10-20) over a 20-year period (Nogaro et al. 2020).

The burden of ACL injury on young people is considerable, in terms of significant medical, social and psychological costs.

These include being unable to participate in sport for over a year, which influences their physical and mental well-being, and has knock on effects on their academic performance.

In addition, the risk of re-rupture, knee osteoarthritis (OA) and permanent disability later in life is markedly increased, with 50 % showing some change at 10-years (Lewis et al. 2018).

There are also important implications for health inequalities, as there has been a surge in female football participation across schools and clubs and females have a higher risk of ACL injury (Maniar 2022).

Injury prevention is the largest modifiable risk factor that has an impact on this problem and evidence suggests injury prevention programs in young athletes reduce the chances of sustaining these injuries by 50 to 70% (Huang et al. 2019; Mandelbaum, 2005).

Some countries like Australia have sport specific programs, while in other countries they have implemented national programs, for example Skadafri in Norway (www.skadafri.no).

Despite the backing of important specialist societies, such as British Orthopaedic Association (BOA), British Society of children's orthopaedic surgeons (BSCOS), and Federation of Exercise and Sports Medicine (FESM), to date there is no public policy on injury prevention programs in the UK.

Indeed, there is limited understanding of what occurs now and what barriers and facilitators may exist to implementing such a program in schools and clubs, which would involve changing both teaching/coaching staff and young peoples' behaviour, as some coaches and/or players may find injury prevention programs too long and complicated to use.

This PhD aims to investigate these issues using mixed methods to inform the next steps towards changing practice and public policy around injury prevention in sports for young people.

Methodology Research plan: this mixed methods PhD will consist of 3 main studies using a combination of methodologies (literature review, survey, and qualitative interviews/focus groups) which together will i) identify current injury prevention strategies, and ii) explore perceived barriers and facilitators to ACL injury prevention implementation.

Study 1: Scoping review The objectives of this review will be to i) identify barriers and facilitators to ACL injury prevention programs for young people, ii) determine the content and contextual factors that support sustained engagement with these programs, and iii) synthesize the evidence on outcome measures previously employed to determine the impact of these ACL injury prevention programs.

The student will follow the scoping review framework by Arksey and O'Malley, updated by Levac and colleagues in 2010.

The scope of inquiry will relate to injury prevention programs for young people (including behaviour change programs targeting teachers/coaches and/or young people themselves) with a broad scope of inquiry related to the barriers, facilitators, and contextual factors of implementation in either public or private sectors (but not elite sports).

The scoping review extension for PRISMA guidelines will be followed throughout and the review protocol will be published a priori. Screening, extraction and risk of bias assessment will be completed in duplicate.

A narrative synthesis approach will be employed informed by the Theoretical Domains Framework (objectives i and ii) to address the revie