Bone density in competitive figure skaters.

OBJECTIVES

To compare the bone mineral density (BMD) of competitive female teenage figure skaters with a history of fracture with the BMD of skaters without fracture and to compare each group to age-matched, nonathletic controls.

DESIGN

Retrospective age-matched cohort.

SETTING

Tertiary care medical center and 3 local skating clubs.

PARTICIPANTS

Thirty-six adolescent female competitive skaters (10 with fracture, 26 without fracture) to 22 age-matched controls.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

BMD was estimated by quantitative ultrasound.

RESULTS

Skaters who had suffered stress fractures had BMD values comparable with those of healthy nonathletic controls. However, skaters who had not suffered stress fractures had calcaneal BMD values 15% to 24% greater than either the controls or skaters with fractures. Among the skaters without fracture, there was a 14% to 19% higher calcaneal BMD in skaters who executed triple jumps relative to skaters who performed only double jumps. Furthermore, there was 7% to 11% greater BMD in the landing foot of the skaters relative to the takeoff foot.

CONCLUSIONS

Stress fractures in adolescent skaters are not caused by low bone mass but may result from excessive forces placed on a normal skeleton. Our findings also support the hypothesis that higher peak forces are applied to the landing foot relative to the takeoff foot.