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Triple Arthrodesis: Intra-Op Positioning

- Positioning of the Forefoot:
     - if there is a tendency to err in one plane, err to place medial forefoot more plantarward than the lateral aspect of the foot;
     - forefoot should be in about 3-5 deg of valgus when ankle is in a neutral position;
     - this valgus forefoot positioning is much more easily overcome by pt than varus forefoot position (which is a more common error);
    - w/ talipes equinovalgus, the medial longitudinal arch is depressed, talar head is enlarged & plantarflexed, & forefoot is abducted;
           - arch is restored by raising talar head & shifting sustentaculum tali medially beneath the talar neck and head;
    - talipes equinovarus, enlarged talar head blocks dorsiflexion & lies lateral to the midline axis of the foot;
           - this is reduced to position slightly medial to midline axis, & it is performed thru subtalar wedge based laterally, combined w/ midtarsal joint resection w/ wedge based laterally;
    - forefoot supination which may result w/ correction of hindfoot valgus deformity is controlled at time of triple arthrodesis through midtarsal joint resection with a wedge based medially;
    - at time of surgery, foot is aligned w/ ankle mortice, not w/ knee;
    - any associated rotational or angular deformity in the remainder of extremity should be corrected by a separate procedure