The Results of Subtalar Arthroereisis for Flexible Flatfoot of Children

거골하 관절 제동술을 이용한 소아 유연성 편평족의 치료 결과

Purpose: We evaluate the results of subtalar arthroereisis with $Kalix^{(R)}$ implant (Newdeal, Lyon, France) that were performed in painful flatfoot deformity. Materials and Methods: We performed the subtalar arthroereisis on 16 feet of children symptomatic flexible flat feet after more than 6 months of conservative treatment. Average age was 11 years (8-14 years) old. We checked the functional status with AOFAS functional score in pre-operatively and at final follow-up. Radiologically, we took weight bearing anterior to posterior and lateral view of the feet, and measured the talo-$1^{st}$ metatarsal angle, calcaneal pitch angle, cuboid-surface height. Finally, we asked to patient's parents for satisfaction of the surgery. Results: Mean follow up period was 34.1 months. Average AOFAS score improved from preoperatively 71.9 to postoperatively 91.3. Only one patient has subtalar pain. Average lateral $1^{st}$ metatarsal angle reduced from $-18.2^{\circ}$ preoperatively to $-4.6^{\circ}$ at final follow-up. Average anterior to posterior $1^{st}$ metatarsal angle was reduced from $18.9^{\circ}$ preoperatively to $6.5^{\circ}$ at final follow-up. Average calcaneal pitch angle was increased from $8.6^{\circ}$ preoperatively to $12.6^{\circ}$ at final follow-up. Average cuoboid-surface height was improved from 12.1 mm preoperatively to 16.0 mm at final follow-up. All patients had excellent or good satisfaction. Conclusions: Subtalar arthroereisis with $Kalix^{(R)}$ implant is a viable surgical alternative for painful flatfoot deformity of children.