Relationship Between Recurrent Adductus Deformity of the Forefoot and Achilles Tendon Elongation Following Ponseti Treatment in Children with Idiopathic Clubfoot.

The plantarflexion-to-dorsiflexion ratio was lower on the involved side (P = .001). No significant differences in the strength ratio of inversion to eversion were found (P = .4). No difference was observed in lengths of tibialis anterior and posterior tendons (P = .1), but the Achilles tendon was longer on the involved side (P = .001; P < .01). A significant negative correlation was discovered between involved-to-uninvolved Achilles tendon length ratios and involved-to-uninvolved plantarflexion strength ratios (r = -0.524; P = .02) Conclusions: Achilles tendon elongation may be a contributor to the muscle imbalance in clubfeet with relapsed forefoot adduction treated by the Ponseti technique.