Medial column procedures in the correction of adult acquired flatfoot deformity

AAFD is a complex problem with a wide variety of treatment options. No single procedure or group of procedures can be applied to all patients with AAFD because of the variety of underlying etiology and grades of deformity. As the posture of the foot progresses into hindfoot valgus and forefoot abduction through attenuation of the medial structures of the foot, the medial column begins to change shape. The first ray elevates and the joints of the medial column may begin to collapse. Careful physical examination and review of weight-bearing radiographs determines which patients have an associated forefoot varus deformity that may require correction at the time of flatfoot reconstruction. Correction of an AAFD requires a combination of soft-tissue procedures to restore dynamic inversion power and bony procedures to correct the hindfoot and midfoot malalignments. If after these corrections forefoot varus deformity remains, the surgeon should consider use of a medial column procedure to recreate the “triangle of support” of the foot that Cotton described.5 If the elevation of the medial column is identified to be at the first NC or the first TMT joint, then the joint should be carefully examined for evidence of instability, hypermobility, or arthritic change. If none of these problems exist, then the surgeon can consider use of the joint-sparing Cotton medial cuneiform osteotomy to correct residual forefoot varus. However, if instability, hypermobility, or arthritic change is present, then the surgeon should consider use of an arthrodesis of the involved joint to correct residual forefoot varus. Either procedure provides a safe and predictable correction to the medial column as part of a comprehensive surgical correction of AAFD.