Objective: To determine the magnitude of lumbar and femoral bone mineral gain in patients with juvenile chronic arthritis (JCA) using dual X-ray absorptiometry.
Methods: Bone mineral density (BMD) was measured at entry and again after 12 months at the lumbar spine and femoral neck in healthy children (n = 65) and children with oligoarticular (n = 36) and polyarticular (n = 69) JCA. Five of the oligoarticular and 38 polyarticular patients were treated with systemic glucocorticoids. In addition to the changes in BMD, the annual changes in calculated bone mineral volumetric density (BMDvol) and bone size were determined simultaneously.
Results: In polyarticular JCA, the acquisition of BMD was decreased at the femoral neck (2.2 vs 4.8%; p < 0.05), but remained the same at the spine compared with healthy children; in oligoarticular JCA, the increase in BMD at the femoral neck was similar to that in controls, but significantly increased at the spine compared with the change in the control group (7.4 vs 4.9%; p < 0.05). The detected annual changes in BMD were associated with the changes in BMDvol. Bone mineral gain was significantly delayed at the lumbar spine in children treated with glucocorticoids.
Conclusion: In children with JCA, the development of bone mineral is different at the lumbar spine and at the femoral neck, but it also depends on the subtype of JCA and on the use of systemic glucocorticoids.