Association between findings on palmarodorsal radiographic images and detection of a fracture in the proximal sesamoid bones of forelimbs obtained from cadavers of racing Thoroughbreds.
OBJECTIVE
To determine the distribution for limbs and bones in horses with fractures of the proximal sesamoid bones and relationships with findings on palmarodorsal radiographic images.


METHODS
Proximal sesamoid bones obtained from both forelimbs of cadavers of 328 racing Thoroughbreds.


METHODS
Osteophytes; large vascular channels; and fracture location, orientation, configuration, and margin distinctness were categorized by use of high-detail contact palmarodorsal radiographs. Distributions of findings were determined. Relationships between radiographic findings and fracture characteristics were examined by use of chi2 and logistic regression techniques.


RESULTS
Fractures were detected in 136 (41.5%) horses. Biaxial fractures were evident in 109 (80%) horses with a fracture. Osteophytes and large vascular channels were evident in 266 (81%) and 325 (99%) horses, respectively. Medial bones typically had complete transverse or split transverse simple fractures, indistinct fracture margins, > 1 vascular channel that was > 1 mm in width, and osteophytes in abaxial wing and basilar middle or basilar abaxial locations. Lateral bones typically had an oblique fracture and distinct fracture margins. Odds of proximal sesamoid bone fracture were approximately 2 to 5 times higher in bones without radiographic evidence of osteophytes or large vascular channels, respectively.


CONCLUSIONS
Biaxial fractures of proximal sesamoid bones were common in cadavers of racing Thoroughbreds. Differences between medial and lateral bones for characteristics associated with fracture may relate to differences in fracture pathogeneses for these bones. Osteophytes and vascular channels were common findings; however, fractures were less likely to occur in bones with these features.
Anthenill
Lucy A
LA
JD Wheat Veterinary Orthopedic Research Laboratory, Department of Anatomy, Physiology, and Cell Biology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA.
Stover
Susan M
SM
Gardner
Ian A
IA
Hill
Ashley E
AE
Lee
Christina M
CM
Anderson
Mark L
ML
Barr
Bradd C
BC
Read
Deryck H
DH
Johnson
Bill J
BJ
Woods
Leslie W
LW
Daft
Barbara M
BM
Kinde
Hailu
H
Moore
Janet D
JD
Farman
Cynthia A
CA
Odani
Jenee S
JS
Pesavento
Patricia A
PA
Uzal
Francisco A
FA
Case
James T
JT
Ardans
Alex A
AA
D017677:Age Distribution; D000818:Animals; D002102:Cadaver; D005260:Female; D005552:Forelimb / Q000000981:diagnostic imaging* / Q000293:injuries*; D050723:Fractures, Bone / Q000000981:diagnostic imaging / Q000662:veterinary*; D006734:Horse Diseases / Q000000981:diagnostic imaging*; D006736:Horses; D008297:Male; D011859:Radiography; D012716:Sesamoid Bones / Q000000981:diagnostic imaging* / Q000293:injuries*; D017678:Sex Distribution