We report the case of an 18-month-old male toddler who was presented with swelling at the medial aspect of the left ankle and walked with a limping gait for one month.

• 摘要软骨母细胞瘤是一种少见之良性骨肿瘤，通常以长骨之骨髓端较易发生，尤其以胫骨，股骨和肱骨之骨髓端最为常见，少部份发生在扁平及短管状形骨之骨髓，如膑骨或跟骨等处。