Case 61: Older Clubfoot with Osteotomy Treated with MAC External Fixator

Abstract

This case describes a 6 year old male with bilateral resistant clubfoot deformities related to be a variant of arthrogrypotic clubfeet. The decision was made to treat with bilateral application of Biomet multiaxial correction (MAC) external fixation system with osteotomy. The use of the MAC external fixator allows for correction and adjustment of angular deformity and displacement in all three planes, including correction of residual or secondary deformities that occur during lengthening. The fixator can correct lower extremity deformities, including clubfoot, and allows the possibility of anatomic alignment within normal radiographic limits. Correction could be accomplished here with one MAC fixator on the midfoot bisector. The deformities can be corrected via a CORA-centric or CORA-perpendicular application. Correction can be accomplished through soft tissues if the joints are intact or osteotomy if the joints are degenerated and bone growth disturbances have occurred. The advantages of external fixation for clubfoot deformity are gradual correction, preservation of joints, correction through bone around deformed joints, post-operative adjustability, and reduced risk to nerves and vessels. Furthermore, if the osteotomy is not at the center of rotation of angulation (CORA), the external fixator can translate to compensate. For this patient’s right foot, we performed a one-level application of the MAC external fixation system with lateral column closing wedge osteotomy of the calcaneus.