Pseudarthrose du scaphoïde carpien bilatérale ou scaphoïde carpien bipartite dégénéré ?

Six new examples of the bipartite trapezoid bone: Morphology, significant population variation, and an examination of pre-existing criteria to identify bipartition of individual carpal bones

“…Though occasionally documented in mesenchymal scaphoids (Thilenius, 1896, in Louis et al, 1976, in newborns (Dwight, 1907), and even documented in serial radiographs (Doman and Marcus, 1990;Tate et al, 2000), many bipartite scaphoid cases are difficult to diagnose with certainty solely employing radiography (e.g., Dubrana et al, 1999;Et-tai et al, 2008). A variety of characteristics of the congenitally bipartite scaphoid have been proposed to differentiate it from traumatic cases including bilateral occurrence, the absence of a history of trauma, similarity in size and density of both portions, the presence of well-defined hyaline covered joints between the two portions, and smooth opposing cortical surfaces with an absence of degenerative changes (Jerre, 1947;Freyschmidt et al, 2003;Beaty et al, 2009), though these are not without criticism (O'Rahilly, 1953; Louis et al, 1976).…”

“…Furthermore, smooth opposing joints should not be considered a necessity since several known cases are cartilage covered in the absence of clear articular facets, and as seen in some bipartite scaphoids (Dwight, 1907), the two portions may be united by fibro-cartilaginous tissue and exhibit roughened or pitted opposing surfaces (Gruber, 1887, this study). Furthermore, pain and osteoarthritis can occur in bipartite scaphoids over time, suggesting that not all bipartite carpals will present with cleanly articulating opposing faces (O'Rahilly, 1953;Et-tai et al, 2008).…”

“…Bipartite carpal bones may be symptomatic (Richards et al, 1987;Kim et al, 2005;Et-tai et al, 2008), misdiagnosed as an ununited fracture (Dwight, 1907), and occur as part of malformation syndromes (Tate et al, 2000;Saccomanni, 2009;Unruh and Shin, 2011) or endocrinopathies including cretinism (O'Rahilly, 1953). Most published cases of bipartite carpal bones involve the scaphoid, though the trapezium, trapezoid, triquetral, …”