Posterior ankle arthroscopy for posterior ankle synovitis with an enlarged posterior talar process caused by a cat bite or scratch: A case report

INTRODUCTION: Legs are sometimes infected and swollen by cat bite or scratch. However, there is no report of synovitis with an enlarged talar posterior process in the posterior ankle caused by a cat bite or scratch which was treated by removal of the enlarged process and synovectomy with release of the flexor hallucis longus tendon via posterior ankle arthroscopy. PRESENTATION OF CASE: The patient was a 58-year-old woman who had started keeping a cat 7 months earlier. She subsequently sustained cat bite and scratch wounds to her lower legs, which gradually became increasingly swollen. On presentation, there was left lower leg swelling, particularly on the posterior aspect of the ankle. Imaging revealed bone marrow edema in the enlarged posterior talar process and inflammation of the adjacent soft tissue. We excised the enlarged posterior talar process, performed synovectomy, and released the flexor hallucis longus tendon using a posterior arthroscopic technique via standard posterolateral and posteromedial portals. Microbial culture was negative. DISCUSSION: The patient returned to daily activities approximately 3 weeks after arthroscopic debridement. There was no recurrence at the 1-year follow-up visit. To our knowledge. CONCLUSION: We report a rare case of posterior ankle synovitis with an enlarged posterior talar process caused by a cat bite or scratch which was treated successfully by posterior ankle arthroscopic debridement.