Musculo-tendinous and joint elastic characteristics during elbow flexion in children

Objective. The aim of the present research was to determine joint stiffness and musculo-tendinous stiffness in children. Background. No reliable data was available on differences in such parameters when comparing children and adults. Methods. Sinusoidal perturbations and quick-released movements were applied to the right elbow during flexion to determine joint stiffness and musculo-tendinous stiffness, respectively. For normalization purposes, stiffness indexes were calculated as the sloped of the relationship, between stiffness and torque. Results Main results were that musculo-tendinous stiffness indexes obtained in children were similar to adult data deduced from the literature. On the other hand, joint stiffness indexes, obtained in children were in the range 0.9-3.8 rad(-1) and were lower than those reported in the literature for adults (between 4 and 8.5 rad(-1)). Conclusion. Since normalized musculo-tendinous stiffness is similar in children and in adults, it can be hypothesized that, during growth, increase in ability to produce force parallels elastic tissue development.