Objectives: To examine the changes in bone strength in a cohort of children with 'growing pains' (GP) after 5 years follow-up and the correlation with pain outcome.
Methods: Bone strength was measured by quantitative ultrasound. Subjects were 39 children with GP previously studied. Controls were normograms based on the measurement of bone speed of sound in 1085 healthy children. Current GP status was assessed by parental questionnaires. Bone strength was compared with pain outcome.
Results: We examined 30/39 (77%) patients after 5 years. Bone strength was significantly increased when compared to the first study (Z score 0.65±1.77 vs. -0.62±0.90, p<0.001). While overall there was no significant difference in the bone strength between the 16 (53%) patients whose GP resolved and the 14 (47%) who continued to have GP episodes (p=0.71), all 6 (20%) patients with a speed of sound Z-score <-1 continued to have GP (p=0.003).
Conclusions: Our findings that pain improves in most patients parallel to the increase in bone strength may support the hypothesis of GP representing in some patients a local overuse syndrome.