How should I apply this information?
Children with juvenile idiopathic arthritis (JIA) who have polyarticular arthritis, growth retardation, reduced weight-bearing activities, biochemical abnormalities of bone formation, and use steroid medications are at risk for low bone mineral density (BMD). With advances in medical management, some children with JIA can tolerate impact exercise.
The authors implemented a 3 times a week/12-week jumping/strengthening program to promote increased BMD in children with oligoarthritic and polyarticular arthritis. They found that the intervention resulted in increased total body BMD at the conclusion of the program and at 3-month follow-up as compared with a control group.
Clinicians cannot assume that all children with JIA will be able to tolerate one hundred 2-footed jumps and a resisted strengthening program. The 5 children who dropped out of the exercise group had a longer disease duration, severity, and higher medication use. More research is needed on tolerance of children with severe arthritis and at greatest risk for low BMD for low-impact and resistive exercise programs.
The authors' report that children in this study did not have decreased BMD, although the tables demonstrate some children had Z scores below −2.0. It is not clear whether they were in the exercise or control group. Specific information on the changes in the femoral neck or lumbar spine in the exercise group is not reported. Thus, interpreting the results is difficult.
What should I be mindful in applying this information?
Therapists need to encourage physical activity (both leisure and structured) and make bone health a priority for children with JIA. All children should be provided with opportunities and knowledge about how to challenge their physical capacity and promote bone health throughout life.
Bone mineral density management needs to be a team process—physical activity, calcium intake, growth hormones, and steroid use all affect BMD. Maximal bone accrual occurs in the presence of growth hormones, for example, prepuberty, so timing of interventions is critical. In addition, medical management must be optimized to allow children to participate in structured or leisure activities that are osteogenic.
Exercise and activity interventions may need to be ongoing or episodic to maintain optimal bone health in children with JIA, given changes in medication, disease state, growth hormones, and natural physical activity.
Maureen T. Nahorniak, PT, MBA, PPI, DPT
Shriners Hospital for Children
Mary E. Gannotti, PT, PhD
University of Hartford