A 61-years old female patient with deep ankle pain in the left ankle. A posterior arthroscopy with debridement and micro fracturing was performed.

Picture 1: CT scan showing the cyst (approximately 1 cm in diameter) with surrounding sclerotic bone.

Picture 2: Talus (1), Calcaneus (2), Cyst (3)

Picture 3: Before and after debridement and micro fracturing.