New research shows lower limb fractures in racehorses repaired under standing sedation have a similar outcome to those repaired under general anaesthetic, but with the advantages of less time, cost and risk.
The study, conducted by Richard Payne and Polly Compston at Rossdales Equine Hospital, Newmarket, has been published recently in the Equine Veterinary Journal.
The report includes details of racehorses with lower limb fractures that were repaired by Rossdales Equine Hospital up to June 2011. Thirty four racehorses were included in the report - thirty Thoroughbreds and four Arabs.
After premedication with acepromazine, sedation was maintained with i.v. boluses of detomidine and butorphanol. Local analgesia (high 4- (or 6-) point block) together with a ring block was performed by the operating surgeon.
Non-displaced fractures included in the study were: incomplete sagittal fracture of the proximal phalanx (14/34 ); lateral condylar fracture of the third metacarpus (12/34); medial condylar fracture of the third metacarpus (7/34 ) and 1 lateral condylar fracture of the third metatarsus. Repair was achieved by the insertion of one or more lag screws.
Hospital records, owner and trainer telephone questionnaires and website research were used to evaluate follow-up. The short and long-term results achieved were comparable with those for similar procedures carried out by the same surgeon under a general anaesthetic. Twenty of the horses returned to racing within an average of 226 days.
On average, the time from completion of the repair to the horse returning to racing was actually shorter when carried out under sedation, than similar cases repaired under general anaesthesia. However, the authors point out that horses selected for standing repair were those with non-displaced fractures which would be expected to require less time to heal than those with displaced fractures that required repair under general anaesthesia.
The authors stressed the need for a competent and experienced hospital team to ensure that health and safety concerns did not become an issue.
“Over the past few years we have been developing an increasing number of techniques, which allow us to perform a variety of surgical procedures in the standing horse. This negates the risks associated with general anaesthesia in our equine patients, which are especially relevant for horses with broken legs, because of their risk of re-injury to the site of fracture repair when the horse stands up again after recovery from anaesthesia” said Richard Payne. “Polly’s study showed that the outcome for racehorses that have a standing fracture repair is every bit as good as for those where the fracture is repaired under a general anaesthetic.”
Read more at equinescienceupdate.com