Os subfibulare - Investigation of an accessory bone

During dissection of a cadaver at the Ohio College of Pediatric Medicine, t he authors encountered the os subfibulare. The os subfibulare was encased w ithin the peroneus longus and peroneus brevis tendons and initially appeare d as though it may have articulated with the left lateral malleolus distall y and posteriorly. The ossicle was not associated with any capsular or liga mentous structures. These findings suggest that the os subfibulare is a tru e sesamoid bone. A review of the literature is presented and the clinical s ignificance of these findings is discussed.