Are bi-axial proximal sesamoid bone fractures in the British Thoroughbred racehorse a bone fatigue related fracture?

M. Kristoffersen; U. Hetzel; T. D. H. Parkin; E. R. Singer

doi:10.3415/VCOT-09-11-0119

Veterinary and Comparative Orthopaedics and Traumatology, Inhaltsverzeichnis

Vet Comp Orthop Traumatol 2010; 23(05): 336-346
DOI: 10.3415/VCOT-09-11-0119

Original Research

Schattauer GmbH

Are bi-axial proximal sesamoid bone fractures in the British Thoroughbred racehorse a bone fatigue related fracture?

A histological study

M. Kristoffersen

¹Department of Veterinary Clinical Science, University of Liverpool, Leahurst, Neston, United Kingdom

,

U. Hetzel

²Department of Veterinary Pathology, University of Liverpool, Leahurst, Neston, United Kingdom

,

T. D. H. Parkin

³Boyd Orr Centre for Population and Ecosystem Health, Faculty of Veterinary Medicine, University of Glasgow, Glasgow, United Kingdom.

,

E. R. Singer

¹Department of Veterinary Clinical Science, University of Liverpool, Leahurst, Neston, United Kingdom

› Institutsangaben

Abstract

Summary

Objectives: To investigate whether micro-fractures and alterations in the trabecular bone area are associated with catastrophic bi-axial proximal sesamoid bone fractures (PSBF).

Methods: Proximal sesamoid bones (PSB) from 10 racehorses with PSBF and from 10 control racehorses without musculoskeletal injury were examined using the bulk basic fuchsin method. Bone histomorphometric and microfracture analysis was performed, and cases and controls compared using two-sample t-test, paired t-test, and Mann-Whitney U test.

Results: There was no significant difference in the microfracture density and the trabecular bone area between bones from case and control horses, and between fractured and non-fractured bones in case horses.

Clinical relevance: Microfracture density was low in the areas of the PSB examined. Microfracture density was not significantly different between groups, indicating that propagation of micro-cracks is an unlikely predisposing pathologic alteration in PSBF in British racehorses. There was no significant difference in the bone surface area between groups, which one would expect if modelling, adaptation and an increase in bone density were associated with PSBF fracture in the case horses. Therefore, PSBF in the British racehorse does not appear to be associated with microfractures of the trabecular bone of the PSB. The PSB fractures might represent an acute monotonic fracture however, the aetiology of the fractures remains unknown with additional research required.

Keywords

Equine - racing - bone - basic fuchsin - micro-fracture

Volltext

Referenzen

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