Peroneal Tendon Dislocation After Total Knee Arthroplasty in a Patient With Hereditary Multiple Exostoses

Case: We report a case of an 81-year-old woman with severe valgus deformity induced by hereditary multiple exostoses, which eventually led to the need for total knee arthroplasty (TKA) due to joint degeneration. Subsequently, she experienced peroneal tendon dislocation. Although changes in knee alignment can affect ankle joint alignment and reportedly lead to ankle pain after TKA, this is a rare case of nontraumatic peroneal tendon dislocation occurring after TKA. Conclusion: This case underscores the complexity of peroneal tendon dislocation after TKA where factors such as pre-existing anatomical abnormalities interact with the alignment changes induced by TKA.