Medial arch orthosis for paediatric flatfoot.

PURPOSE To evaluate any correlation between various foot angles and their respective American Orthopaedic Foot and Ankle Society (AOFAS) scores for pain, and the effectiveness of a medial arch orthosis. METHODS 81 children with bilateral symptomatic flatfoot were randomised into orthosis (n=55) and control (n=26) groups. The orthosis group consisted of 33 male and 22 female patients aged 36 to 204 (mean, 99) months and they were given a medial arch support. The control group consisted of 15 male and 11 female patients aged 36 to 192 (mean, 100) months and they were managed with analgesics. Foot angles including anteroposterior (AP) and lateral talocalcaneal (TC) angles, AP and lateral talo- first metatarsal (TFM) angles, calcaneal pitch angle (in lateral plane), and talonavicular (TN) angle were measured, as were AOFAS scores for pain for the forefoot, midfoot, and hindfoot. RESULTS After orthosis treatment, all AOFAS scores and all foot angles (except for the AP-TN angle) improved significantly. In the controls, all AOFAS scores (except for the midfoot score) and only the AP-TFM angle improved significantly. In the orthosis group, the AOFAS hindfoot score correlated positively with the lateral TC angle of the left foot (r=0.345, p=0.010) and negatively with the calcaneal pitch angle of the right foot (r=-0.33, p=0.015). In the control group, the lateral TFM angle of the left foot correlated negatively with the AOFAS forefoot (r=-0.566, p=0.003) and midfoot scores (r=-0.497, p=0.001), whereas the calcaneal pitch angle of the left foot correlated positively with the AOFAS forefoot score (r=0.497, p=0.010). CONCLUSION Medial arch support orthosis significantly improved AOFAS scores and foot angles. Calcaneal pitch angle and lateral TC angle correlated well with AOFAS hindfoot scores.