11 year-old QH-WB cross gelding used for dressage, currently schooling third level. Problems began 2 years ago after reaction to rhinitis A vaccine, when the horse appeared to have tied-up. Was given 6 months off, then was brought back to work. Horse did not return to 100% soundness after rest period. After this time, the owner and horses moved to another state. Horse seemed to handle the move and was doing well. 6-7 weeks prior to presentation, when the owner noted that the horse began acting strange on the cross ties, and appeared uncomfortable and spastic in the hind end. The behavior progressed to hindlimb shaking and spasm, with delayed limb placement and wide-based end stride at a walk and while backing up (see video 1). Additionally, the farrier had significant difficulty picking up the hind legs, to the point that shoeing became nearly impossible. The horse became painful to touch and would almost collapse when palpated over the gluteal region. The horse had a thorough work-up by his regular veterinarian, who suspected hock and/or sacroiliac (SI) joint issues. The SI joints were injected 10 days prior to presentation. No improvement was noted. Coggins and Lyme’s Disease titer were negative. EPM and PSSM testing were also negative. Thyroid levels were slightly low, so thyroid supplement was initiated. No improvement was noted by the horse’s owner after treatment was initiated.
At presentation, horse walked stiffly with wide-based stride behind and narrow-based stride in forelimbs. When asked to back-up, he was reluctant to lift the hind limbs and held them upward and outward for an abnormal period of time before placement. Foot placement was random and unpredictable. He had significant difficulty lifting rear limbs and holding them up.
There was significant hypomobility (lack of motion) in the lumbar spine and SI joints. The pelvis was carried higher on the right side than the left. The sacrum was tilted so that the right side (base and apex) was higher than the left. The horse’s sternum was shifted to the right side.
Treatment: Chiropractic adjustments,acupuncture, fore and hind limb stretches, and athletic taping.
Acupuncture treatment focused on trigger points along the bladder meridian at the lumbar spine, SI joints, and sacrum. Acupuncture points for treatment of sciatic pain were also used. Athletic tape was placed along the lumbar spine extending beyond the SI joints, with a piece also placed across the SI joints for stabilization.
After the treatment, the horse was stall rested with handwalking for 48 hours, after which regular daily turn-out schedule was resumed. The owner decreased the horse’s riding schedule for a two week period, then gradually began increasing the duration and intensity of work.
Follow-up: Owner reported improvement within two weeks of treatment (see video 2). The horse was walking better, was not acting strange while cross tied, was able to back-up comfortably, and it was easier to lift feet for picking and farriery. He had a second treatment 3 weeks later, then a third treatment two weeks later. Chiropractic adjustments, acupuncture, and athletic taping were done during each treatment session.
After the second treatment, the owner reported that the horse continued to progress under saddle. At the third treatment session, the owner reported that the horse was doing well and was able to do his lead changes during riding sessions.
The most likely diagnosis is shivers, based on physical examination and ruling-out of other diagnosable disorders. Stringhalt is also possible, however this horse did not display the typical upward “slapping” movement of the hindlimbs when in motion. Shivers is believed to be a peripheral nerve disorder with an unknown cause and no known cure. Acupuncture is likely helpful initially in these cases, as it does stimulate peripheral nerves and modulate the nervous system. Caution is warranted, as this condition is progressive, so over time the acupuncture will most likely become less effective over an unpredictable length of time (weeks, months, or years).