When you have navicular accessory does the bone swell or the tendon?

Tendon: a major tendon of the foot attaches to the navicular, or in your case the accessory navicular. Pulling at this attachment is painful and is a typical complaint for a foot type that has this structure. Swelling occurs as a result of inflammation at this attachment.

Not my navicular !!: Actually the inflammation can occur at the periosteal level of both the tendon attachment site as well as the accessory navicular/ navicular inter-attachment site. The swelling is your body trying to immobilize the area to hopefully allow the structures to stabilize and minimize movement. This is your bodies solution to your problem.