Subtalar repositional arthrodesis for adult acquired flatfoot

Arthrodesis of the subtalar joint is well recognized treatment option for moderate or severe flatfoot associated with adult acquired flatfoot secondary to posterior tibial tendon dysfunction. The success of the subtalar arthrodesis is dependent on restoration of normal bony relationships in the hindfoot and midfoot. For this reason, a distinction is made between a repositional arthrodesis and the traditional in situ type of arthrodesis. An in vitro study of the adult acquired flatfoot identifies an anteroposterior subluxation of the subtalar articulation that can be corrected durably and reliably through a repositional talocalcaneal arthrodesis. Intraoperative reduction techniques are useful in obtaining reduction of the peritalar subluxation. There are certain clinical features that help identify patients with flatfoot deformities who are good candidates for subtalar fusion. As the pathoanatomy of the flatfoot deformity is better elucidated, treatment techniques are modified to better address the key elements of the deformity. A repositional subtalar arthrodesis was shown to produce excellent correction in a moderate to severe in vitro flatfoot example in the authors' clinical series.