Background The popularity of organized sports, especially team sports is growing among youth. High training volume and intensity at early age may predispose young athletes to overuse injuries.

Objective To examine the occurrence, nature and severity of overuse injuries in youth basketball and floorball.

Design A descriptive retrospective study.

Setting Finnish youth basketball and floorball.

Participants: 406 athletes (mean age 15.9, SD 2.0) from six basketball and floorball clubs (210 basketball and 196 floorball players).

Main outcome measurements Self-reported history of overuse injuries over the preceding 12-month period. Data was obtained from a questionnaire. The severity of injuries was defined according to time-loss from full-time game or training.

Results 172 overuse injuries (sustained by 139 players) were reported. Basketball players sustained 97 and floorball players 75 overuse injuries. Injury incidence in basketball was 1.1 and in floorball 0.8 injuries/1000h of exposure. Most of the overuse injuries involved the lower extremities (72% of all injuries). Most commonly injured site was the knee (45%). Another common site of the injury was the area of lower back/pelvis (26%), followed by the calf/shin (11%). No differences between the genders or the two sports were observed. Most of the injuries were slight (time-loss 1–3 days) injuries (33%). 23% of injuries were mild (time-loss 4–7 days), 20% were moderate (time-loss 8–28 days) and 25% of injuries were severe (time-loss ≥29 days) injuries. Overuse injuries caused an average time-loss of 24 days (SD 52).

Conclusions Over a one third of the players participating in the study reported having sustained an overuse injury in the preceding 12 months. Remarkable proportion of overuse injuries were severe injuries. Overuse injuries often cause long absence from full-time game and training. Prospective studies to assess the risk factors and mechanisms of overuse injuries among youth team sports are needed.