Bone Health in Children and Adolescents With Juvenile Idiopathic Arthritis and the Influence of Short-term Physical Exercise

In Brief Purpose: To study bone mineral density (BMD) in 54 children and adolescents with juvenile idiopathic arthritis before and after a short-term exercise program. Methods: Fifty-four children, 41 girls and 13 boys, median age 13.9 years, participated in a 12-week exercise program, with 33 children in an exercise group. The program consisted of one hundred 2-footed jumps with a rope and standardized muscle strength exercise. Both BMD and bone mineral content were assessed with dual-energy x-ray absorptiometry (DXA) and DXA Laser Calscan for the heel at the start and after 3 and 6 months. Results: The study group had BMD measurements within the reference range compared with normative data with Z score at start. Bone mineral density values in total body, but not Z score, increased significantly (P = .012) in the exercise group. Conclusions: The study group had BMD measurements within the reference range. Twelve weeks of exercise increases BMD in children with juvenile idiopathic arthritis. In this randomized clinical trial the authors found that 12 weeks of exercise involving rope jumping and strengthening for the core, shoulder, and arm musculature increased bone mineral density in children with juvenile idiopathic arthritis.