Incidence, prevalence and risk factors for symptomatic lumbar bone stress injury in female and male youth cricket bowlers

OBJECTIVES: To determine incidence, prevalence of and risk factors for lumbar bone stress injuries in youth cricket bowlers. DESIGN: Prospective observational cohort study. METHODS: Asymptomatic youth bowlers between 10 and 20 years were recruited and tested pre- and post-season for anthropometrics and factors related to lumbar bone stress injury risk. Bowling workload and lumbar bone stress injuries were monitored across the season. RESULTS: Ninety-eight bowlers (75 males, 23 females; mean age 14.3 ± 2.2 years and 13.6 ± 2.0 years) were tested pre-season, and 93 (74 males, 19 females) post-season. At baseline, 12.2% reported a previous lumbar bone stress injury. Seasonal lumbar bone stress injury prevalence was 16.3%, corresponding to 1.1 injuries per 10,000 deliveries, with a lifetime prevalence of 28.6%. Lumbar bone stress injury prevalence was highest among bowlers with a previous lumbar bone stress injury, corresponding to 3.8 injuries per 10,000 deliveries. Injured fast bowlers were more biologically mature (p = 0.030) and, in unadjusted analyses, were taller, heavier, bowled faster, and had higher bone density measures. After adjustment for sex and biological maturity, only previous lumbar bone stress injuries remained associated with injury (p = 0.028). Spikes in acute:chronic workload ratio occurred within six weeks of diagnosis. CONCLUSION: Lumbar bone stress injury prevalence and injury rates remain high in youth bowlers, with injuries clustering during mid-adolescence around peak height velocity and strongly associated with previous lumbar bone stress injury history. Increases in bowling workload preceding diagnosis highlight proactive workload monitoring and management as a key target for primary injury prevention.