Published in modified form in "Equus"
Wesley called us out on a cold January morning to see Windy, a 23 year old grey Thoroughbred mare, a former jumper now used for trail riding.
He wanted a second opinion. Windy had a unilateral, right sided nasal discharge that had drained for weeks and she had been on a five day course
of trimethoprim-sulfa, an oral antibiotic, prescribed for a respiratory infection. The discharge had decreased and then returned.
We examined Windy standing in the snow. She had a necrotic, fetid odor we could smell from feet away and this tall mare only weighed 870 pounds,
a BCS of 3.
Greenish white pus drained from her right nostril, but her temperature was normal and heart and lungs were fine. We noted melanomas underneath her tail.
Windy had additional problems; her fetlocks dropped in both front legs and she had a buttress foot on the right front, old tendonitis in the left.
Her back and hindquarters were sore to palpation, her hocks were stiff, and she had stringhalt in the left hind. Her jumping career had taken a toll.
We carefully sedated Windy with Xylazine and an oral exam with full mouth speculum revealed a missing right upper first molar (#109) with at least
one palpable fragment. There was significant feed impaction in the gap and obvious periodontal disease. Jim flushed the area. There were no sharp
enamel points as Windy’s teeth had reportedly been floated 5 months prior.
We took x-rays of Windy’s skull and x-rayed her front feet. Jim prescribed Bute for her discomfort and advised Wesley to begin a diet of softened
senior concentrate.
Five days later, we again met Wesley and Windy in the snow. X-rays had shown infection in the maxillary bone, osteomyelitis, above the fragmented
roots of the missing tooth. X-rays of the feet showed a defect in connection of the extensor process to the rest of the coffin bone, a congenital
defect that had not kept this gallant mare from jumping. There was advanced degenerative bone disease; arthritic spurs, around the coffin joints—ringbone.
Once again, we sedated Windy. We created a small hole into the paranasal sinus with a sterile bone pin—a trephine procedure—to flush the sinus and
sample fluid from there. We wanted bacterial cultures and sensitivities to treat the bone infection we could see on the skull x-rays. Jim prescribed
metronidazole, an antibiotic used for deep seated infections caused by bacteria that grow in areas without air (anaerobic infections), and trimethoprim-sulfa once again. We continued Windy on Bute.
We pulled blood samples to send to the lab and made a plan to bring Windy to the clinic, but Wesley wanted to treat Windy’s lameness; he wanted to
know if the mare could live out her life in orthopedic comfort before he let us extract her infected tooth. The antibiotics had stopped her nasal discharge.
Blood work was essentially normal and Windy’s sinus culture did not grow; the bone infection from the tooth had broken through into the nasal passage
rather than the sinus. Wesley asked Jim to treat Windy’s front feet.
Jim injected Windy’s coffin joints with triamcinolone and a farrier shortened her toes and applied egg bar shoes with wedges to take pressure off
the coffin joint bone spurs. Windy’s walking markedly improved and she continued with 1 gram of Bute twice daily. We planned on her dental extraction in a matter of weeks.
Wesley’s fortunes dipped in winter and it was one year later before he called to treat her teeth and her feet once again. He planned to find her a
home in a gentler climate.
Wesley transported Windy to our clinic. This time we took a swab of pus from her nasal discharge, and the culture grew two bacteria; the pseudomonas
was resistant to trimethoprim-sulfa antibiotics. We started Windy on gentamicin, an antibiotic that would work, and once again injected her coffin
joints. The farrier trimmed and shod the mare.
Using a combination of dormosedan, xylazine and butorphanol, sedatives and pain relievers, Windy was sedated in our stocks. Jim performed an
infra-orbital nerve block and extracted the infected tooth fragment and roots. He curetted and flushed the socket and probed the wound but the
opening into the nasal passage (the fistula) was not evident.
In younger horses, infected tooth roots more commonly erode into the sinus and a surgical procedure may be done (a bone flap opened into the sinus)
to curette the alveolar socket, the fistula, and the sinus. The socket may be packed with dental impression material and the sinus bone flap closed.
Windy’s fistula into the nasal passage was more easily treated with daily flushing of her mouth using a hose, syringe or turkey baster and diluted
chlorhexidine solution. Her nasal discharge resolved, and her mouth now smelled like sweet hay. She gained 80 pounds in 6 weeks and was walking well.
Wesley eventually found Windy a home through a rescue group as a companion horse. Over a year later she had no foul odor, her weight was good, and she
was bright and alert. She had a very slight thin nasal discharge, a drippy nose. When last we saw her turned loose at her pasture gate, she loped off
to join her friend. Her remaining years would hopefully be good with the attention of her caretakers to her mouth and feet, and good quality senior feed.
