Accessory Calcaneus: A Case Report and Literature Review

Abstract

A case of bilateral accessory calcanii is presented in which the accessory ossicle articulated with the talus and calcaneus at the lateral aspect of the posterior facet of the subtalar joint, causing premature subtalar degenerative changes in a 19-year-old man. Although rare and usually asymptomatic, accessory ossicles around the foot may need surgical excision if painful or if sufficient size is obtained to cause deformity and/or limitations in range of motion.

Pathoanatomy of posterior ankle impingement in ballet dancers

“…There is a single report of an accessory ossicle located posterior to the fibular malleolus (Callanan et al, 1998). This anomaly differs from the more commonly described subperoneal/subfibular ossicle located inferior to the lateral malleolus (Hirschtick, 1951; O'Rahilly, 1953; Krause and Rouse, 1995; Mellado et al, 2003). Callanan et al described a 1.0cm by 1.5 cm ossicle discovered in addition to an os trigonum in a 28‐year‐old female.…”

Progressive Pes Adductus Caused by an Accessory Calcaneus: A Case Report

“…The reason for this may be that Trolle 24 described the location of the accessory calcaneus as under the fibular malleolus, mistaking it for a talus secundarius, which usually is in close contact with the tip of the fibula. 5,12 The ossicle we excised is the largest described in the literature. We also did not find a comparable case with similar deformities in the shape and size of the foot.…”

“…The nomenclature of accessory bones of the calcaneus is more than confusing. 12,19 The calcaneus secundarius should not be confused with the calcaneus accessorius ( os trochleae ). 19,23 The former has been well described in clinical, radiographic, and cadaver studies.…”

Anatomical variation in the ankle and foot: from incidental finding to inductor of pathology. Part I: ankle and hindfoot

“…Several rare accessory bones in the hindfoot have been described, such as an accessory calcaneus, by Krause and Rouse [30], and bipartite configurations of the talus that can be mistaken by fractures [31–33].…”