FIELD REVIEW: A CASE STUDY Sam is an 18-year-old Thoroughbred gelding being used
as a pleasure horse. His owner requested infrared thermography to check saddle fit and foot balance.
Infrared thermography is a noninvasive physiological tool that measures surface heat on the body of the horse, using a hand-held camera. The thermography technician stands several feel away from the horse to take the images. The heat pictures of the horse's anatomy can be viewed in "real time," using a TV screen or the camera LCD.
Images are saved in the thermography camera, then downloaded into a computer to be further studied for abnormal heat patterns and asymmetries. An abnormal heat pattern, whether hot or cold, can indicate WHERE the problem is but not diagnose WHAT the problem is. The images can be used as part of clinical evaluation for foot imbalance, saddle fit, vague lameness or training stress. Printed images are also useful in the horse?s health record for future comparison.
Sam's owner wanted to rule out foot imbalance and saddle fit problems before embarking on a traditional lameness workup. The current lameness in Sam's left fore had been an intermittent problem for the past year, occurring several days after shoeing. Predating the lameness, he had felt stiff in the front end, especially going downhill. Sam had a past history of racing injuries and documented degenerative joint changes in both ankles.
The veterinarian who examined Sam utilized clinical exam, lateral foot x-rays and thermographic foot images to make recommendations for the farrier. She suggested unloading the quarters, shortening the toe and providing more heel support. Several weeks after these changes had been implemented, Sam improved ... until he was saddled.
Sam' vet and saddle fitter both agreed that his all-purpose English saddle no longer fit him. The veterinarian?' chiropractic assessment revealed wither findings consistent with chronic saddle pressure. He responded well to the wither adjustment.
Prior to the saddle fit thermography, Sam was ridden for 15 minutes in the ring at a walk, trot and canter in both directions. The goal was to develop a heat pattern on his back from the saddle, but not become sweaty. Next we took him into the barn, closing doors and windows to avoid draft and light, which can create false hot or cold readings.
After removing the saddle, the saddle panels were immediately imaged for the heat
pattern (without the pad). These images showed intense heat bilaterally where the saddle sits behind the withers. In changing the heat setting to better define the area of intense heat, it could be seen that there was more heat on the left side. Next, images of Sam's back were taken from both sides and a rear view looking down on his back.
A printed set of images with the thermographic report was supplied to the veterinarian and the owner. At this point, there was correlation on the area of poor saddle fit from veterinarian exam, saddle fitter assessment and thermographic imaging.
A month later, Sam's owner called to tell me he was sound in a new adjustable tree saddle. She requested a saddle fit thermography to help determine appropriate tree size. Her saddle fitter had ruled out several as too wide for Sam. Although the horse was happy in a medium, she felt like she was pitching forward.
Using the same process, we imaged the saddle panels and Sam's back after riding for 20 minutes. The saddle panels had a more even heat pattern, although not quite symmetrical. Sam?s back images had bilateral spots of heat below the withers. It was not clear how much of this was saddle and how much might be attributable to the mild rain rot on his back. Surface dermatitis shows up hot on thermography.
Based on her feeling of pitching forward in the new saddle and the spots of wither heat, Sam's owner inserted a narrower tree size. She reported that she felt balanced, Sam went happily and she plans to continue riding in this tree size. After the rain rot is fully cleared up on Sam's back, we will schedule another saddle fit thermography.
Sam's owner wanted to address two important basics, saddle fit and foot balance. The case demonstrates the collaboration of owner, vet, farrier and saddle fitter. Infrared thermography played a role in the shoeing evaluation by detecting abnormal heat patterns in how the horse was landing. Thermographic images of the saddle and back correlated with the horse?s way of going under saddle, the veterinarian?s clinical exam and the saddle fitter?s assessment.
Debbie LaBerge, RN, MSN, is the owner of ThermoHorse Equine Thermography Service, a non-veterinary service providing thermographic images and reports to horse owners, veterinarians and farriers. She can be reached at 717-529-2158 or firstname.lastname@example.org