Digital cameras extend DVMs' diagnostic vision

Digital cameras extend DVMs' diagnostic vision

May 01, 2002

Use of digital cameras at shows, competitions, and other events can provide evidence of perfect gaits and motion or point out problems and deficiencies. The use of film review in all aspects of human sports development has greatly improved performances and similar gains can possibly be seen in equine sports.
What is the most important piece of equipment in your truck or clinic?

Is it your X-ray machine or perhaps your ultrasound? Could it be your blood chemistry analyzer or simply your stethoscope or hoof tester?

While a case can be made for any of these, possibly the most important device in equine practice today may be the digital camera or digital video recorder.

Recent improvements to these devices have upgraded the quality, enhanced the usability and decreased the cost to a point where every trainer and equine veterinarian should have one.

In his paper, "Video analysis of gait in horses," Dr. Kevin Keegan, DVM, MS, writes that video cameras allow for an evaluation of equine athletic ability. The use of such cameras also enable veterinarians and trainers to monitor progress with training, to detect changes caused by trimming and shoeing and to measure lameness.

Keegan lists the two main benefits of digital camera use as "providing a medium for objective measurement and expanding the temporal resolution of the human eye (which is only about 0.1 sec)".

Simply stated, digital cameras and camcorders allow the viewer to see more, to save what was seen for later comparison and to dissect complex motion so that the human eye can process all of the available information. Given this capacity to capture and help utilize information, it may not be that much of a stretch to call a digital camera one of your most important pieces of equipment.

Nothing new Cameras and film use have been solving problems in equine sports medicine for a long time.

Digital images can be taken and stored allowing veterinarians and owners to keep visual records of parameters that should be monitored. Hoof angles and shoeing concerns should be recorded. Healing wounds, tumor growth, gait changes, and nutritional improvements are only some of the aspects of horse care that lend themselves to digital record keeping.
In 1877 American photographer Eadweard Muybridge and French physiologist Etienne Jules Marey collaborated to do a series of studies on equine gait. Prior to this time, writes Dr. P. Rene van Weeren, professor of equine surgery at Utrecht University, "treatises on gait analysis had largely consisted of theoretical considerations while conclusions based on experimental data were scarce. This was largely due to the limitations of the human eye when observing the faster gaits."

A review of the prominent equine art of that period would show racing horses painted with front legs stretching out in front and with both hind legs pushing out behind. From our 21st century vantage point it seems silly that anyone would have thought that horses actually moved like that but we have been able to slow down horse gaits and have actually seen how they move. Without the benefit of cameras we would never know.

And it was Muybridge and Marey who finally documented that there are indeed times when all four limbs of a horse are off the ground at the same time (This was a point that had been argued reportedly since the time of the Egyptians).

By using 24 cameras in linear array, these early gait analysis pioneers uncovered previously unseen (and unsuspected) characteristics of the gaits of the horse. This array of cameras and some modification in their mechanics reduced exposure time to 1/6000 of a second. Whole new worlds of information were now available to owners, trainers and veterinarians.

New worlds Similarly, the recent development of low cost, high quality digital camera and video equipment and the software to develop and store pictures and video are opening up new worlds to modern equine practitioners.

Digital cameras allow veterinarians to take pictures of radiographs, skin irritations, ocular conditions, wounds, tumors and other lesions. These digital images can then be quickly sent to any number of experts via e-mail. Detailed and timely responses can improve diagnosis and treatment of field cases.
How often do you find yourself looking at a lame horse and asking the client if this horse always dragged his toes, or ever trotted with his tail cocked to the left or swung out the leg at the stifle on turns to the right? Most times there is no prior information and nothing to compare the current lameness to. Contrast this to major league baseball where a New York Yankee batter can call up a digital video, look at all the pitches he may have faced from a particular pitcher and watch himself swing at all those balls.

Such a detailed look can help to point out subtle imperfections in movement and can show changes from past good performance as a means of pinpointing and correcting a problem.

Catching up From golf swings to 3-point shots to deep sidelines passes, human athletes use digital film evaluation everyday. Equine sports medicine is just beginning to catch up.

Imagine if your clients had a video record of their horse's gaits when the animal was fine and moving normally. Comparison between the videos may help focus on specific areas of lameness and could help with diagnosis and treatment of the problem. Problems such as saddle-fit, rider imbalance and other training issues can be focused upon and perhaps helped by using digital video analysis as well.

Shoeing concerns Digital cameras can be tremendously helpful in dealing with farriers and with shoeing concerns.

A simple lateral digital photo can be projected on the computer or television screen and measurements can be made of hoof length, angles and breakover points.

Digital video can provide information concerning loading and landing aspects of the foot and can show foot flight and leg motion.

These digital photos can be saved and used at the next shoeing to compare growth, wear, and other dynamic aspects of the horse's foot.

Farriers may be able to stay more consistent with their trimming of some feet if they are provided with a video record of the horse in question. This non-subjective record of what the foot looked like and what its measurements were would be a great help to the farrier. More correct, more consistent shoeing could therefore be developed.