OBJECTIVE: To determine the thickness and width of the calcaneal tendon (Achilles tendon) in both male and female, eutrophic children at 2, 6, 9 and 12 months of age. MATERIALS AND METHODS: The present prospective and descriptive study included 38 boys and 31 girls. Measurements of the tendons were performed by means of ultrasonography, with a linear, 14-MHz probe, at the level of the medial malleolus. RESULTS: Tendon thicknesses observed in the boys were 2.4 mm, 2.3 mm, 2.4 mm, and 2.4 mm, respectively at 2, 6, 9 and 12 months. Widths were, respectively, 6.0 mm, 6.4 mm, 6.7 mm and 7.1 mm. In the girls, the tendon thicknesses observed at 2, 6 and 9 months were 2.4 mm, and 2.5 mm at 12 months. Widths were, respectively, 5.7 mm, 6.2 mm, 6.5 mm and 6.5 mm. CONCLUSION: No difference was observed in the calcaneal tendon thickness between boys and girls along the first year of their lives; however, width measurements demonstrated differences.

Keywords: Calcaneal tendon, Ultrasonography, Children