Two-stage ankle arthrodesis using the induced membrane technique for pyogenic arthritis: a case report.

Background: Ankle arthrodesis is the most frequently performed salvage procedure for pyogenic arthritis. However, its failed fusion rate of approximately 15% has been considered problematic. Herein, we present a case of pyogenic ankle arthritis successfully treated via a two-stage surgical procedure on the basis of the induced membrane technique.

Case Presentation: A 43-year-old Japanese male patient with alcoholic liver disease was referred to our institution. He complained of persistent ankle pain and local heat following osteosynthesis for a closed pilon fracture. Radiological examinations revealed massive destruction of the ankle joint. Cultures of samples obtained from the joint isolated Streptococcus viridans. On the basis of these findings, he was diagnosed with pyogenic ankle arthritis with osteomyelitis of the distal tibia and talus. We performed the two-stage procedure per the induced membrane technique. In the first stage, the necrotic and infected tissue was debrided, and a polymethylmethacrylate spacer was inserted into the bone defect. Intravenous antibiotics were administered for 1 week thereafter. In the second stage, which was performed 5 weeks after the first stage, the induced membrane was identified around the polymethylmethacrylate spacer and cut to remove the latter. Ankle arthrodesis was performed with three double-thread screws. Finally, the autologous cancellous bone graft harvested from the ipsilateral iliac crest was used to fill the bone defect. During the postoperative period, antibiotics were administered intravenously for 2 weeks. Blood examinations normalized 3 weeks after the second stage. The immobilization splint was maintained for 6 weeks, after which partial weight bearing was started, and 6 months after surgery, the patient returned to full weight bearing and walked confidently without ankle pain. Radiological evaluations performed 2 years after the second stage revealed complete consolidation, and he reported no pain while walking.

Conclusion: Ankle arthrodesis performed via the induced membrane technique not only successfully controlled infection, but also achieved complete bone union, enabling the preservation of ankle joint. This technique demonstrates its potential as a highly effective approach for treating pyogenic ankle arthritis.