Belmont winner Rags to Riches back in form after bone scan
Sep 01, 2007
Sired by Belmont Stakes winner A.P. Indy and half-sister to 2006 Belmont Stakes winner Jazil, Rags to Riches has five wins in five starts in 2007 and earnings of $1,292,528.
But just six weeks after Belmont, Rags to Riches spiked a fever while stabled at Belmont Park on New York's Long Island and was quickly declared out of the July 21 Coaching Club American Oaks race.On Sunday morning, July 22, Rags to Riches was to breeze five furlongs but, after just one-sixteenth mile into the workout under exercise rider Lauren Robson, she was pulled up abruptly. Though the 3-year-old filly reportedly showed no signs of injury, Robson felt something was amiss and took the horse back to the barn.
Whether Rags to Riches stepped on something or just took a bad step is unknown.
Dr. Steve Allday, DVM, was called to give the horse a physical exam the next morning. While finding her generally sound and in good condition, Allday believed it prudent to recommend she be taken to the University of Pennsylvania's New Bolton Center for a complete physical, including a bone scan.
Nuclear scintigraphy is an effective methodology for horses where lameness is minimally detectable, cannot be localized or remains uncertain after a common lameness exam and radiographs that determine bone damage, especially to limbs and pelvis.
A bone scan involves intravenous injection of a radioactive tracer substance, Technectium 99m, bound to a phosphate compound, 99mTc-MDP, "the bone-seeking agent," or tracer. The tracer travels first through the blood (phase 1 or vascular phase), which may show impaired circulation in a limb; then to the soft tissues (phase 2), which may show an area of inflammation, possibly a problem with the suspensories, a tendon; and finally to the bone, where a concentration of material indicates increased bone metabolism/increased bone remodeling (i.e., possible fracture, stress fracture or infection).
The vascular phase is noted immediately post-injection, the soft-tissue phase within 30 minutes post-injection and the bone phase within two to three hours. Areas that particularly absorb the material are known as "hot spots," as opposed to those that do not, dubbed "cold spots."
The "gamma camera" takes bone images, picks up the radioactivity and notes these hot and cold areas as darker and lighter aspects of the computer-generated images.
That completed, other modalities, including "blocking," radiographs, ultrasound and/or MRI, can be used to further diagnose the potential injury site.