Anatomy of the os trigonum. ³

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Grogan DP. Walling AK. Ogden JA. Journal of Pediatric Orthopaedics. 10(5):618-22, 1990 Sep-Oct. Three anatomic specimens of os trigonum from skeletally immature patients demonstrated anatomic continuity of the cartilage containing the ossicle with the body of the talus, with a synchondrosis being present between the two ossifying regions. The os trigonum may be considered a developmental analogue of a secondary ossification center similar to the posterior * calcaneal apophysis (although there are obvious histologic differences). The chondro-osseous border of the synchondrosis may be injured either as a chronic stress fracture or, less frequently, as an acute fracture, Á comparable to the injury patterns involving the accessory navicular. * Á