Presentation
Medial foot pain
From the case:
Accessory navicular bone
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There is an accessory bone located on patient's posteromedial tuberosity of the tarsal navicular bone. The accessory bone has a cartilaginous connection to the navicular best seen on T2 sequence which suggests it is a type II accessory navicular bone.
Case Discussion
Accessory navicular bones are also known as os tibiale externum or os naviculare and are considered a normal anatomical variant; although it can cause a painful tendinosis.