Computed tomography identifies the proximodorsomedial subchondral bone of equine central tarsal bones as a predilection site for sclerosis, demineralisation and associated fractures.

BACKGROUND

The distribution pattern of central tarsal bone (CTB) changes has not been described, except for slab- and dorsomedial-plantarolateral fractures.

OBJECTIVES

To describe CTB changes in CT and document their distribution and associations.

STUDY

DESIGN

Retrospective case series.

METHODS

Standing and recumbent tarsal CT studies from 94 clinical cases were retrospectively evaluated. General case information, degree of sclerosis (none-severe), lesions (demineralisation, cystoid, fissure/fracture) and their location were recorded, dividing CTBs into 8 regions.

RESULTS

Eighty five of 94 tarsi showed at least one region of moderate to severe sclerosis, of which 90% affected the dorsomedial region. The prevalence of lesions was significantly associated with higher degrees of sclerosis (p = 0.04) at this site. Of 32 demineralising lesions, 21 were in the proximal subchondral bone dorsomedially. Twenty-four CTBs showed fissures/fractures; 19/24 were in a dorsomedial-plantarolateral direction, and 17/19 were associated with demineralisation. Of five fissures/fractures with different configurations, none had associated demineralisation. There were 27 cyst-like lesions, 21/27 in the distal subchondral bone, of which almost half (13/27) located medially.

MAIN LIMITATIONS: Retrospective design; heterogeneous, warmblood-oriented population; no clinical correlation of findings nor histological confirmation of described changes.

CONCLUSIONS

Given the links between sclerosis, demineralisation and fissures/fractures, the dorsomedial proximal subchondral bone plate of the CTB must be scrutinised both in CT and radiography.