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bunion
X-ray of feet showing the structural deformity of the big toes caused by bunions.
bunion
pathology
bunion, type of bursitis that appears as a bulge covered by thickened skin occurring at the base of the big toe, where friction against the side of the shoe takes place. The protuberance is due to a swelling of the bursa mucosa, a closed sac filled with a clear, lubricating fluid. The bunion causes pain, localized tenderness, and limitation of motion, and it results in permanent deformation, forcing the toe toward the little toe.
This article was most recently revised and updated by Amy Tikkanen.
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