Fracture of calcaneus - Sanders CT classification of intra-articular fractures

The Sanders classification is based on CT evaluation of calcaneus in coronal plane. The classification was published in 1992 and it takes into account location and number of fracture lines. The image is evaluated in coronal plane where it shows the posterior articular facet in its widest (latero-lateral) profile, where the location of primary fracture line with relation to the posterior articular facet is determined (intra-articular fracture).

Type Description
Type I undisplaced articular fractures (<2mm) of the posterior facet irrespective of the number of fracture lines
Type II two-part fracture of the posterior facet (one fracture line)
IIA: primary fracture line is lateral
IIB: primary fracture line is central
IIC: primary fracture line is medial
Type III three-part fracture of the posterior facet with a centrally depressed fragment (two fracture lines)
IIIAB: primary fracture lines lateral and central
IIIAC: primary fracture lines lateral and medial
IIIBC: primary fracture lines central and medial
Type IV more than three-part highly comminuted articular fractures of the posterior facet (≥ three fracture lines)


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