Written by a Medical Acupuncture for Veterinarians Course Graduate. Author’s name available upon request. Signed release obtained from client/author.
A nine-year-old mare with a combination of right masseter muscle atrophy, increased radio-density of the tympanic bullae, atypical behavioral reactions to high-pitched noises, and increased sensitivity to palpation of the left-ear region was treated twice with selected acupuncture points. The results showed a notable decrease in the sensitivity to palpation of the left-ear region.
The chestnut quarter horse mare was purchased two years ago with an unknown medical history. At the time of acquisition, the mare was very head shy, had a depression within the caudal aspect of the right-masseter muscle, and was excessively sensitive to palpation of the left ear, left neck, and poll. Since that time, the owner has reported exaggerated spooking behaviors in response to high-pitched noises, such as whistling or birds chirping. A year ago, the mare was seropositive to borrelia burgdorferi and treated with minocycline for 30 days. The mare has several conformation flaws in the distal forelimbs that have contributed to some degree of variable lameness and a shortened gait in the forelimbs. A week-long course of Phenylbutazone was effective in changing the mare’s behavior in response to palpation the left-ear region.
Physical Examination and Clinical Assessments
Previous evaluation of the above mare found a clinically healthy mare. The presenting complaint of increased sensitivity to palpation of the left-ear region was verified to be accurate and consistent. The mare had increased sensitivity and a painful response to palpation of the left and right ventral tempormandibular joint regions, left ear, left poll, and left throat latch region. Endoscopic evaluation of the left guttural pouch was within normal limits. A fibrinogen level was within normal limits. Radiographs of the skull and guttural pouch revealed a mild increased radio-density to the tympanic bullae. Otoscopic exam was non-remarkable. Myofascial exam indicated pain adjacent to the temporomandibular joints, poll, left ear region, and bilateral descending pectoral and triceps muscle strain patterns. The mare has regular dental care and a tendency to develop hooks on the caudal lower molars, which have been managed appropriately.
Medical Decision Making
Given the mare’s unknown history of masseter muscle atrophy, facial sensitivity, and irregular behavior to high-pitched noises, historical cranial trauma was a possible etiology to the mare’s condition. Radiographic changes in the tympanic bullae are suggestive of an infection, however given the normal fibrinogen and history of the mare having been treated with a long course of antibiotics for the borrelia burgdorferi, it was considered less likely to be actively infected at this time. The mare tolerated palpation of her left- ear region when she was on phenylbutazone, suggesting that there was a pain component not a primary behavioral problem. For lack of a primary etiology to the clinically significant sensitivity of the temporomandibular joint, ear, and poll region, we elected to treat specifically for neuropathic pain of the facial, trigeminal, and cranial cervical nerves. The mare had her annual dental floating done at the same time as the first treatment.
All points were treated bilaterally with dry needling. Electroacupuncture was not chosen for this mare due to her increased sensitivity. Laser therapy was not an option for my treatment at this time, but would have been used with caution around the eyes, if it had been available.
LI-16 and GB-21 where used as the first points for their calming effects through the cervicothoracic nerves. BL-10 and GB-20 were used to stimulate neuromodulation of the cranial cervical nerves. TH-17 was used to achieve neuromodulation of the facial nerve trunk and treat the presumptive diagnosis of facial nerve pain. ST-7 was used to create neuromodulation through the trigeminal and facial nerves. There was a painful response to palpation and tension along the cranial border of the master muscle at this location.
The mare is quite sensitive and a bit needle shy, therefore a minimal amount of acupuncture points were chosen. Smaller needles, 0.16mm and 0.18mm diameter, were used on the first treatment of the facial points. For the second treatment, larger 0.20mm diameter needles were used for all points.
The mare has received two treatments of the same acupuncture point combinations one week apart. I have scheduled to re-examine and treat on a weekly basis for the next three weeks. If the mare is tolerant to more needles, I would consider adding more points such as SI-19 and GB-2 for added neuromodulation of the facial and trigeminal nerves. I hope to be able to treat the mares other myofascial strain patterns in her descending pectoral muscles (LU-1) and triceps muscles (SI-9 and trigger points) on the next visit.
After the first treatment, the owner was able to scratch the inside of the mare’s ear and around her neck and poll without a violent reaction. The follow-up exam indicated no reaction to palpation of the mare’s poll, ear, or throat latch area. There was still mild sensitivity to palpation of the temporomandibular joint region (ST-7.) The mare did have hooks on the lower caudal molars removed at the same time as the first treatment. This may have contributed to the mare’s improvement. The same dental procedure was done last year, and the owner did not appreciate any improvement in comfort or behavior, but was unlikely to have been looking for a specific correlation at that time.
After the second treatment, the mare has become very fond of having her left ear rubbed and massaged.
Acupuncture has been reported to be beneficial in the treatment of trigeminal neuralgia in humans and otitis media in dogs. Given that this mare has an longstanding unknown history of discomfort in the facial and trigeminal nerve regions, as well as a reaction to certain noises and an radiographic abnormality of her inner ear, acupuncture is a good choice of treatment for her. Other treatment options include gabapentin to treat the nerve pain and a second course of antibiotics as an attempt to treat a possible inner-ear infection. Obtaining a culture for a definitive diagnosis and antibiotic selection is not practical in this case, therefore treating with antibiotics may prove unnecessary or lack effectiveness. Gabapentin could be useful if the mare does not respond to the acupuncture alone.
“Successful treatment of a resistance trigeminal neuralgia pain with acupuncture” (Huseyin Sert et al.) Clinics(Sau Paulo). 2009 Dec; v64(12) 1225-1226
“Acupuncture enhances the efficacy of antibiotic treatments for canine otitis crises” (Snachez-Araujo M., Puchi A.) Acupunct Electrother Res. 1997;22(3-4):191-206