Serum insulin-like growth factors IGF-I and IGFBP-3 in children with slipped capital femoral epiphysis

Hormonal imbalance in puberty and biomechanical overload due to obesity hav e been implied in the still unknown cause of slipped capital femoral epiphy sis (SCFE). Local mediators of growth hormone (GH) action, such as insulinl ike growth factor I (IGF-I), play a crucial role in the development of the growth plate cartilage. Concentrations of IGF-I and its binding protein 3 ( IGFBP-3) were measured in the serum of 19 SCFE children without endocrine d isorders. Standing height and body weight were determined. The results were related to the bone age. Concentrations for IGF-I and IGFBP-3 were predomi nantly within the normal ranges for chronologic age and bone age. The corre lation of IGF-I and IGFBP-3 serum levels was high. Standing height and body weight showed a tendency toward the higher percentile ranges. Ten of 19 pa tients were above the 97th percentile concerning their weight for height. B one age did not differ significantly from chronologic age. Serum concentrat ions of IGF-I and IGFBP-3 provided no evidence of a disturbance of the soma totropic axis in SCFE children. Increased body weight associated with norma l skeletal maturation implies a mechanical stress factor in the cause of SC FE in these children.