Background : The incidence of injury to the triceps surae muscle (TS) in front row rugby union (rugby) players has stimulated a need to investigate the events surrounding this injury. Previous research has linked TS injuries with scrummaging1, but mechanisms of injury remain unidentified. Purpose : The purpose of this study was to investigate the lower limb kinematics of a cohort of front row players during a series of scrummaging drills. It was hypothesized that analysing the biomechanics of this aspect of game play would provide understanding about the possible mechanisms for TS injury. Methodology : Eleven front row rugby players were videoed during a series of scrummaging drills. Land marked anatomical points were digitised and a three-dimensional model of the trunk and lower limb developed. Independent t-tests were conducted to determine if the lower limb kinematics differed between defensive and attacking scrummaging technique. All statistical analyses were performed using SPSS for Windows (version 17). A significance level of p < 0.05 was used for all analysis. Results and Discussion : Results (presented as mean ± SD) showed numerous significant differences in a range of variables between defensive and attacking scrum types. Analysis indicated a trend towards more extended joint positions at toe off and toe strike during scrum drills. For example, ankle angular displacement at toe off varied significantly (p < 0.001) between the attacking (126 deg [± 10]) and defensive scrum drills (111 deg [± 7]), as did ankle angular displacement at peak extension velocity during single leg stance (p = 0.024) between the attacking (108 deg [±12]) and defensive scrum drills (97 deg [± 9]).
Queensland Injury Prevention Council – Evidence to Action Symposium, Townsville, Australia 18-19 November 2010