シャルコー神経関節症患者における踵骨部分切除術

It is well documented that limb salvage interventions may induce or exacerbate biomechanical dysfunction in the residual limb. As a result, patients with Charcot's neuroarthropathy (CN) are at theoretical risk for progression of or novel neuroarthropathic breakdown, which has been observed in the midfoot after amputation; however, this has not been investigated in rearfoot interventions such as partial calcanectomy.

We retrospectively identified eight patients during a 7.25-year period who had a history of CN and partial calcanectomy in the ipsilateral limb. Patients with contralateral involvement were excluded, and included medical records were analyzed and radiographically characterized.

The mean patient age was 73.9 years (range, 59-86 years), and the mean body mass index was 31.4 (range, 22-50). Two patients (25.0%) demonstrated multijoint breakdown. Two feet (25.0%) were characterized as Sanders-Frykberg (SF) II, one (12.5%) as SF III, and three (37.5%) as SF IV/V breakdown. Three patients developed CN a mean of 350.3 days after partial calcanectomy was performed. The mean age and body mass index of patients who experienced post-vertical contour calcanectomy CN was 70.7 years (range, 59-83 years) and 29.0 years (range, 22-35 years), respectively. All instances of postcalcanectomy CN resulted in rearfoot breakdown, with one (33.3%) isolated to the tibiotalar joint and two (66.7%) at the tibiotalar and subtalar joints. A 66.7% limb salvage rate was found in patients who developed postcalcanectomy CN.

We conclude that partial calcanectomy in patients with antecedent CN does not result in clinically significant changes that further threaten the limb but identified three instances where partial calcanectomy destabilized the rearfoot and resulted in rearfoot CN breakdown. Although this knowledge should not discourage the use of calcanectomies, clinicians should be cognitive of complications such as CN breakdown that can further threaten the limb.