Article Text
Abstract
Objectives Most concussions in rugby union occur during tackles. We investigated whether legislation to lower maximum tackle height would change tackle behaviour, and reduce concussion incidence rate.
Methods In an observational evaluation using a prospective cohort design, 12 elite men’s teams played in two competitions during the 2018/2019 season. The Championship (90 games) retained standard Laws of Rugby for the tackle; the Championship Cup (36 games) used revised laws—the maximum tackle height was lowered from the line of the shoulders on the ball carrier to the line of the armpits. Videos of tackles were analysed for ball carrier and tackler behaviour. Injury data were collected using standardised methods.
Results In the lowered tackle height setting, there was a significantly lower proportion of tackles; (1) in which ball carriers (rate ratio (RR) 0.83, 95% CI 0.79 to 0.86) and tacklers (RR 0.80, 95% CI 0.76 to 0.84) were upright, (2) in which the tackler’s initial contact was to the ball carrier’s head or neck (RR 0.70, 95% CI 0.58 to 0.84) and (3) in which initial contact was above the line of the ball carrier’s armpit (RR 0.84, 95% CI 0.80 to 0.88). Concussion incidence rate did not differ between conditions (RR 1.31, 95% CI 0.85 to 2.01). Unexpectedly, compared with the standard tackle height setting, tacklers in the lowered tackle height setting were themselves concussed at a higher rate as measured by; (1) incidence (RR 1.90, 95% CI 1.05 to 3.45) and (2) concussions per 1000 tackles (2.09, 95% CI 1.15 to 3.80).
Conclusions Legislating to lower the height of the tackle meant that tacklers made contact with the ball carrier’s head and neck 30% less often. This did not influence concussion incidence rates. Tacklers in the lowered tackle height setting suffered more concussions than did tacklers in the standard tackle height setting.
- rugby
- injury
- concussion
- injury prevention
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Footnotes
Twitter @drkeithstokes, @drsimonkemp
Correction notice This article has been corrected since it published Online First. Various amendments have been made to the text throughout the article.
Contributors The study was designed by KAS, SK and DR. Data collection was carried out by KAS, SR, LH and DL. Data analysis was carried out by KAS, DL and RT. The first draft of the manuscript was prepared by KAS. All authors contributed to revisions of the manuscript and approved the submitted version.
Funding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.
Competing interests KAS, DL, LH and SK are employees of the Rugby Football Union, which is the governing body for Rugby Union in England. RT is employed by World Rugby, which is the governing body for the sport of Rugby Union and responsible for law changes in the sport.
Patient consent for publication Not required.
Ethics approval Ethics approval for collection of all injury data (REACH: EP 17/18 170) and specific concussion data (REACH: EP 16/17 286) was given by the University of Bath.
Provenance and peer review Not commissioned; externally peer reviewed.
Data availability statement No data are available.