Total Talar Replacement for Idiopathic Necrosis of the Talus: A Case Report

Idiopathic osteonecrosis of the talus is a rare but severe condition that directly affects the ability to walk and is difficult to treat either conservatively or surgically. We report the case of a 72-year-old female with idiopathic necrosis of the talus treated with total talar replacement surgery. A custom-made aluminum-ceramic total talar prosthesis was prepared using the mirror image of the computed tomography and radiographic data from the contralateral ankle. The talus was exposed and removed using an anterior approach, and the total talar prosthesis was inserted. The prosthesis was placed in a stable position between the tibia, calcaneus, and navicular, with no signs of instability with ankle joint movement. The ankle was immobilized in a short-leg cast for 3 weeks. At the latest follow-up examination, 2 years after surgery, the patient was walking without pain. Examination of the left ankle showed 20° of dorsiflexion and 40° of plantar flexion. The American Orthopaedic Foot and Ankle Society ankle/hindfoot score was 90, which had improved from a preoperative score of 45. Radiographic examination showed that the prosthesis was in a stable position in the ankle mortise, and no degenerative or destructive changes were observed in the surrounding bones. This is the first reported case of total talar replacement with a prosthesis for idiopathic talar necrosis. Although the long-term outcome is still unknown, this procedure could provide a good treatment option for idiopathic necrosis of the talus.