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Musculoskeletal modelling is widely used in biomechanics for the analysis and simulation of human motion. A modelling approach allows estimates of the internal load on specific anatomical structures, and the individual muscle forces that govern movement execution. Within the analysis of impact events in rugby union, modelling can help the understanding of the mechanisms of acute and chronic cervical spine injuries, starting from experimental measures of external load on the player, and progressing to the estimation of stresses acting on the internal cervical structures. During this part of the applied session, we will use a novel musculoskeletal model and previously collected experimental data (forces and kinematics) to analyse the cervical spine loading experienced during a rugby scrum. An open-source biomechanical software (OpenSim 3.2) will be used to set up and run inverse and forward dynamics pipelines to calculate joint moments and joint reaction forces, and to analyse “what if…” scenarios.

Biomechanical studies of rugby union scrummaging have focussed on kinetic and kinematic analyses, whilst muscle activation strategies employed by front row players during scrummaging are still unknown. The aim of this study was to investigate the activity of the sternocleidomastoid, upper trapezius and erector spinae muscles during machine and live scrums. Nine male front-row forwards scrummaged individually against a scrum machine under 'crouch-touch-set' and 'crouch-bind-set' conditions, and against a two-player opposition in a simulated live condition. Results suggest that the pre-bind technique, may effectively prepare the cervical spine by stiffening joints before the impact phase. Additionally, machine scrummaging does not replicate the muscular demands of live scrummaging for the erector spinae.

Primarily using rugby union situations as case study examples for the practical demonstration, the initial part of the session will discuss both familiar and emerging techniques to measure the biomechanics of sport impact situations. We will cover some of the issues that need to be accounted for to acquire robust data in such complex environments, and we will discuss how experimental measures can be either used in their own right to develop knowledge of impact biomechanics or can provide data to input a modelling pipeline and for model validation purposes.

This study consisted of a video incident analysis of rugby tackles leading to spinal injuries, where players’ behaviours and observed loading mechanisms were coded for each incident. The key features of these events were summarised, revealing the role of highspeed impacts, illegal tackles, and poor tackle technique in injury-causing tackles. In addition, lateral bending moments and lateral flexion movements were more prevalent than suggested by previous research. This investigation informed an experimental protocol for the analysis of simulated rugby tackles, with the final goal to obtain measures of cervical spine biomechanics during tackles. Data captured from this protocol could alsobe input into a full-body musculoskeletal model to provide descriptions of internal cervical spine loading in different tackle event scenarios.

The aim of this paper is to present the “Biomechanics of the Rugby Scrum” project, a three-year research programme that thoroughly studied the kinematics and kinetics of rugby union scrummaging with a view to identifying safer scrum engagement techniques. The outcomes of the study will be analysed and their implications for injury prevention and performance will be discussed.

The kinematics of walking on treadmill were collected and the 3D trajectory of the body centre of mass was computed in subjects suffering from mono-lateral knee osteoarthritis, before and after total knee arthroplasty. Experimental data showed after 6 months from surgery significant improvements in many biomechanical parameters as gait symmetry indices and total work done.