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.
(Copyright 2002 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation)