Racing performance after arthroscopic removal of apical sesamoid fracture fragments in Thoroughbred horses age < 2 years: 151 cases (1989--2002).
BACKGROUND
Studies on arthroscopic removal of apical proximal sesamoid fracture fragments in Thoroughbred (TB) horses age > or = 2 years have reported a high success rate. However, there are no reports documenting the racing prognosis of TB horses that undergo such surgery as weanlings or yearlings.


OBJECTIVE
To describe the incidence of apical proximal sesamoid fractures in immature TB horses, age < 2 years and determine probability and quality of racing performance after arthroscopic removal of such fractures in 151 TB weanlings and yearlings.


METHODS
The medical records of TB horses age < 2 years that underwent arthroscopic surgery for removal of apical proximal sesamoid fracture fragments were reviewed. Follow-up information was obtained from race records. Student's t tests were used to compare performance variables of operated racehorses to that of their maternal siblings.


RESULTS
Ninety-two percent (139/151) of fractures occurred in the hindlimbs and 8% (11/151) in the forelimbs (fracture of both fore- and hindlimb, n = 1). Horses with forelimb fractures had a greatly reduced probability of racing (55%) compared to those with hindlimb fractures (86%). Overall, 84% of the horses raced post operatively and had performance records similar to that of their maternal siblings, 78% (787/1006) of which raced.


CONCLUSIONS
Arthroscopic removal of apical proximal sesamoid fracture fragments in TB weanlings and yearlings carries an excellent prognosis for racing in horses with hindlimb fractures and a reduced prognosis in those with forelimb fractures. Medial fractures of the forelimb carry the worst prognosis.


CONCLUSIONS
The determination of prognosis increases knowledge on apical sesamoid bone fractures and potential for arthroscopic restoration of the ability to race; and enables the value of yearlings for subsequent sale to be established.
Schnabel
L V
LV
Rood and Riddle Equine Hospital, PO Box 12070, 2150 Georgetown Road, Lexington, Kentucky 40580, USA.
Bramlage
L R
LR
Mohammed
H O
HO
Embertson
R M
RM
Ruggles
A J
AJ
Hopper
S A
SA
D000367:Age Factors; D000818:Animals; D001182:Arthroscopy / Q000379:methods / Q000662:veterinary*; D005260:Female; D005552:Forelimb / Q000293:injuries / Q000601:surgery; D050723:Fractures, Bone / Q000601:surgery / Q000662:veterinary*; D006614:Hindlimb / Q000293:injuries / Q000601:surgery; D006736:Horses / Q000293:injuries / Q000601:surgery*; D008297:Male; D010805:Physical Conditioning, Animal / Q000502:physiology*; D011379:Prognosis; D012189:Retrospective Studies; D012716:Sesamoid Bones / Q000293:injuries* / Q000601:surgery*; D013177:Sports; D016896:Treatment Outcome