Combined Internal and External Fixation for Charcot Neuro Arthropathy: 1 Year Results

Abstract

Category: Diabetes Introduction/Purpose: Complex foot and ankle deformities secondary to charcot neuroarthropathy continue to represent a significant challenge and management quandary. This is due to the combination of medical co-morbidities, peripheral neuropathy, immune compromise, and micro/macro vascular issues in addition to the surgical challenge of wide area of injury, progressive deformity and bone resorption. The technique of 'superconstructs' have been proposed as a method of combating these challenges with deformity correction achieved through fusion out with the zone of injury and fixation in unaffected 'normal' bone. We present here the outcomes of this technique at one year using internal fixation alone, external fixation alone and the novel technique of combined internal and external fixation using combined internal and external fixation internal/ external fixation only at one year. Methods: Retrospective two-surgeon case series with all cases jointly operated upon. Cases identified from a locally held charcot patient registry. Patients undergoing charcot foot and ankle reconstruction from 2017 to 2020 included. No exclusion criteria outlined. Patient demographics and comorbidities were collected, pre-op radiological markers (meary's angle) measured and repeated at 6-12 /52 and 1 year. Patient outcomes were recorded of ulcer recurrence, limb salvage, pain score, stable heel, able to ambulate, need for revision surgery, fusion and surgical complications. Proms are awaited for all patients. Results: 19 cases from 18 patients undergoing reconstruction identified. 18 cases were included for analysis. Fourteen patients were broadsky 1, one broadsky 2, one broadsky 3 and two broadsky 4. 3 patients had internal fixation, 5 external fixation and 10 combined internal and external fixation. Limb salvage was 94% with one amputation. Mortality rate was nil. All patients reported improved pain scores, a stable heel and were ambulating. No recurrence of ulceration reported and no prolonged antibiotic use. Mearys angle improved in all groups: Internal fixation pre-op -9.6o, post op 2.6o and 1 year -1o, external fixation pre-op -20o, post op -6o and 1 year -12o, IF + EF pre-op -24.6o, post op 1.2o and 1 year -2.3o. Fusion rate was 100% with average time to fusion 154 days and a range of 360 - 52. Complications of 2 tibial fractures and metalwork removal with delayed wound healing were noted. Conclusion: The outcome of all three methods is positive with 94% limb salvage, 100% fusion / ambulation/ improved pain and ulcer free at 1 year. Mearys angle is improved at one year however there is a loss of correction noted with external fixation alone. These results are encouraging and support the use of combined internal and external fixation in these complex cases. The added benefit of this technique of maintaining ambulation, avoiding the complications of nonweightbearing all whilst maintaining the structure of the reconstructed foot are promising. The complications reported were in the first 3 patient and represent a learning curve.