Lumbar and cervico-thoracic spine loading during a fast bowling spell: Lumbar and cervico-thoracic spine loading during a fast bowling spell

Context: Epidemiological studies highlight a prevalence of lumbar vertebrae injuries in cricket fast bowlers, with governing bodies implementing rules to reduce exposure. Analysis typically requires complex and laboratory-based biomechanical analyses, lacking ecological validity. Developments in GPS micro-technologies facilitate on-field measures of mechanical intensity, facilitating screening toward prevention and rehabilitation. Objective: To examine the efficacy of using GPS-mounted tri-axial accelerometers to quantify accumulated body ‘load’, and to investigate the effect of GPS unit placement in relation to epidemiological observations. Design: Repeated measures, field-based. Setting: Regulation cricket pitch. Participants: 10 male injury-free participants were recruited from a cricket academy (18.1 ± 0.6yrs). Intervention: Each participant was fitted with two GPS units placed at the cervico-thoracic and lumbar spine to measure tri-axial acceleration (100 Hz). The participants were instructed to deliver a 7 over ‘spell’ of Fast Bowling, as dictated by governing body guidelines. Main Outcome Measures: Tri-axial total accumulated body and the relative uni-axial contributions were calculated for each over. Results: There was no significant main effect for overs bowled, either in total load or the tri-axial contributions to total load. This finding suggests no cumulative fatigue effect across the 10-over spell. However there was a significant main effect for GPS unit location, with the lumbar unit exposed to significantly greater load than the cervico-thoracic unit in each of the tri-axial planes. Conclusions: There was no evidence to suggest that accumulated ‘load’ significantly increased as a result of ‘spell’ duration. In this respect the governing body guidelines for this age group can be considered safe, or potentially even conservative. However the observation of higher body ‘load’ at the lumbar spine compared with the cervico-thoracic spine supports epidemiological observations of injury incidence. GPS micro-technologies might therefore be considered in screening and monitoring of players toward injury prevention and/or during rehabilitation.