Abstract
Category:
Hindfoot; Diabetes; Midfoot/Forefoot
Introduction/Purpose:
Chronic dislocations of the hindfoot and midfoot are a treatment challenge due to difficulties in achieving re-alignment without bone or soft tissue compromise. Neuropathy and diabetes are often associated with the chronic foot dislocation, and further complicate treatment. Our prior studies with integrated fixation methods (ring external fixation and internal fixation) for severe tibia pilon fractures and deformed, infected neuroarthopathic ankles has shown that internal fixation around the ankle can be safely combined with external fixation in single stage procedures.In this study, a staged approach is utilized to limit bone resection and minimize risks of soft tissue compromise and neurovascualar injury with severe and rigid defomity corrections. The purpose is to assess the results and complications of this surgical treatment approach.
Methods:
Medical records, clincal evaluation, and radiographs for 9 patients treated with gradual hexapod realignment and staged arthrodesis of chronic foot dislocations were retrospectively reviewed. There were six female and three male patients with a mean age of 59 (range, 43-71) years. Follow-up ranged from 12 months to 12 years. All had neuropathy; seven were diabetic, one CMT, one idiopathic, and one rheumatoid. Dislocation was present for a minimum of 16 weeks (range, 4 to 36 months). Seven patients had preoperative ulcerations. Seven had peritalar dislocations (subtalar and talonavicular), and two had midfoot dislocations (naviculocuneiform-1, talonavicular-1).Treatment protocol included: Surgical stage 1- soft tissue releases and Taylor spatial frame application; gradual correction of dislocation; Surgical stage 2-open arthrodeses with internal fixation and frame modification or removal.
Results:
All nine patients achieved a stable plantigrade and functional foot position. All fusions healed except for one talonavicular nonunion. All preoperative ulcerations healed. Six patients with peritalar dislocations had frame modification at the time of arthrodesis (mean frame time was 5.9 months). Three patients had frame removal at time of arthrodesis (mean frame time was 3 months). Average time from hexapod realignment to arthrodesis surgery was 8 (range, 3-16) weeks.Outcome with the Reinker/Carpenter scale was 5 excellent, 2 good, and 2 fair. Two peritalar dislocations developed complications; one talonavicular nonunion, and one deep infection. Other complications included further surgery in two midfoot dislocations, two forefoot wire complications, and one ankle deformity during peritalar correction.
Conclusion:
Staged integrated realignment/arthrodesis for chronic neuropathic foot dislocations resulted in good clinical outcomes with manageable complications. The Taylor spatial frame miter and butt constructs were successful in reducing hindfoot and midfoot dislocations, respectively. There was reliable fusion and ulcer healing with our staged protocol. This case series furthers our successful clinical results with the combined use of ring external fixation and internal fixation methods for complex foot and ankle pathology.