Article Text
Abstract
Background The incidence of shoulder injury resulting from the tackle in rugby union football is high and the tackle is as well the main cause of injury. Little is known about the magnitude of tackle forces and influencing factors.
Objective To measure the force applied to the shoulder in the tackle, the effect of shoulder padding, skill level, side of body, and player size.
Design Repeated measures design. In counterbalanced order, participants tackled a 45 kg tackle bag five times in the four conditions: dominant versus non-dominant sides; with and without shoulder pads.
Setting Community level rugby football. The selection criteria were: (1) age 18–25 years old, (2) played at least 3 years of rugby, and (3) played at least a season of rugby within the last 3 years.
Participants 35 participants were recruited.
Interventions IRB approved shoulder pads.
Main outcome measurements Maximum impact force was measured with a custom built forceplate incorporated into a 45 kg tackle bag.
Results The overall average shoulder force was 1660 N. The average impact force for tackling without shoulder pads was 1684 N compared to 1635 N for wearers. Shoulder pads reduced the peak impact forces by 3% (p>0.05). There was a 6% difference in the average impact force between the dominant (1708 N) and non-dominant sides (1611 N). Tackle repetition was found to be a statistically significant factor as the impact forces reduced from the first tackle (1743 N) to the fifth tackle (1571 N) (p<0.05). No relationship was observed between player skill level and size.
Conclusion Shoulder pad performance needs to be improved. Although the shoulder force in the tackle is normally tolerated without injury, its magnitude is within the reported tolerance threshold range for sternoclavicular joint and glenohumeral joint. Fatigue may be an injury risk factor in the tackle.