Introduction Prospective studies investigating risk factors for low back pain (LBP) in young athletes are limited. The aim of this prospective cohort study was to investigate the association between LBP and selected biomechanical factors and postural stability during dynamic movement tasks in young athletes.

Materials and methods 396 young floorball and basketball players (mean age 15.8±1.9) were included and followed prospectively for 1–3 years (2011–2014). In the beginning of every study year the players were tested. The physical tests included single-leg squat (SLS), single-leg vertical drop jump (SLVDJ), vertical drop jump (VDJ) and Star Reach Excursion Balance Test (SEBT). Individual exposure time and LBP resulting in time-loss were recorded prospectively. Cox’s proportional hazard models with mixed effects and time-varying risk factors were used.

Results In SLVDJ landing with non-dominant leg, the risk for general LBP and non-traumatic LBP in specific, was significantly higher with increased femoral adduction (HR 1.10, 95% CI 1.02–1.19 and HR 1.12, 95% CI 1.03–1.22, respectively) and significantly lower with increased in femur-pelvic angle (FPA; angle-between pelvis and femur) (HR 0.93, 95% CI 0.88–0.99 and HR 0.92, 95% CI 0.86–0.99, respectively). However, the ROC analysis revealed poor combined sensitivity and specificity for femoral adduction and for FPA.

Conclusions Increased femoral adduction and decreased FPA during SLVDJ landing are associated with risk of LBP in young team ball players. However, the identified risk factors do not discriminate players with or without future LBP well enough and therefore further studies on effect of neuromuscular training on lumbo-pelvic control and LBP incidence are warranted.