Impacting the rugby tackle: risk factors and mechanisms for concussion and musculoskeletal tackle-related injury - a systematic review and Delphi consensus to inform intervention strategies for risk reduction.

To (1) systematically review the literature to identify which match-related risk factors and mechanisms of rugby tackle events result in musculoskeletal injury, concussion, head injury assessments, and head impacts or head accelerations; and (2) identify the perceived importance and feasibility of potential intervention strategies for tackle-related injury reduction in the rugby codes.A systematic search was performed using Preferred Reporting Systematic Reviews and Meta-Analyses guidelines. Risk factors/mechanisms associated with tackle injuries across the rugby codes were extracted. After extraction, 50 international rugby experts participated in a Delphi poll. Via content analysis, expert-recommended risk factors/mechanisms were developed. In round two, experts rated all risk factors and mechanisms for importance to injury risk. In round three, the feasibility of law changes, coach and player education, and training as interventions to reduce injury risk for each injury risk factor/mechanism deemed important during round two was rated.PubMed (MEDLINE), Scopus, SPORTDiscus (EBSCOhost) and CINAHL.Eligible studies included cohort, observational and cross-sectional designs, which included male or female rugby union, league or sevens players.37 eligible studies were identified, with 138 injury risk factors/mechanisms extracted. 70% of the studies were rated 'high quality', with 30% moderate quality. 38 new risk factors/mechanisms were recommended by the expert group, 8 being identified as important and highly feasible for modification by an intervention strategy. 'The tackler placing their head on the incorrect side of the ball carrier' was described as the most important mechanism, with 'training' and 'coach/player education' thought to be highly feasible interventions.Numerous risk factors or mechanisms associated with tackle-related injury appear important and modifiable, helping to guide interventions to reduce injury risk in the rugby tackle.