ABSTRACT OF THE WEEK

Journal of the American Veterinary Medical Association
Volume 261 | Issue 6 (June 2023)

Difficulty walking and trembling in a 10-year-old female Akita Inu.

J Am Vet Med Assoc. June 2023;261(6):926 - 928.

Evelina Burbaitė, Marika Menchetti

Companion Notes

Case report of orthostatic tremors in a dog

Introduction on primary orthostatic tremors (OTs)

- benign involuntary movement disorder

- usually reported in young giant- or large-breed dogs

- between 9 months and 2 years of age

- but in retrievers it seems to appear later in life

- involves progressive involuntary, high-frequency tremor in hindlimbs

- primarily affecting them during the standing position

- can progress to most often involve the forelimbs

- but also the trunk and head

- affected dogs appear reluctant to lie down

- they can have difficulty in sitting and standing

- tremors can be confused with weakness or exercise intolerance

- typically tremors disappear when affected legs are raised from the ground

- or during walking, sitting, or lying down

- OTs can be divided into primary OT (considered idiopathic) and OT-plus

- OT-plus involves OT in dogs with other concomitant neurological disease

- diagnosis of primary OTs is based on the following:

- typical clinical presentation

- positive weight-bearing lifting test

- conscious EMG in weight-bearing posture showing high-frequency tremors

- “helicopter sign”

- sound resembling a distant helicopter during auscultation with stethoscope

(over limb with tremors)

- in human medicine

- regardless of medication, response is often scarce and minimal

- clonazepam is the 1^st choice

- second-line options include the following:

- gabapentin

- primidone

- sodium valproate

- carbamazepine

- phenobarbital

- deep brain stimulation used successfully

- in canine medicine

- medication options appear to give a higher rate of improvement than humans

- gabapentin and phenobarbital used in most recently published reports

- improvement is usually partial

Case report of 10-year-old 29.3 kg [64.6 lb] neutered sex:F dog

- history of a commercial diet and regular vaccination

- at referral for difficulty in walking and trembling in hindlimbs of 6 years' duration

- tremors progressed in last 4 months, mildly involving the forelimbs

- physical examination: unremarkable

- neurological examination

- limb tremors, while standing

- mostly hindlimbs and very mild in forelimbs

- disappeared in lie-down position

- difficulty in sitting

- positive weight-bearing lifting test

- tremors discontinued after lifting and keeping hindlimbs air-floating

- neurolocalization

- tremors predominantly in limbs

- triggered by standing and discontinuing after keeping hindlimbs air-floating

- and during lie-down position

- suggestive of orthostatic tremors

- lesion involving 1 or more of the following suspected:

(considering recent literature)

- suspect spinal cord lesion involving 1 or more of the following:

- ventral gray column

- α-motor neurons

- spinal cord gray matter interneurons

- intracranial structures (brainstem and cerebellum)

- likely location of lesion using human medicine concerning orthostatic tremors

- central generator, called the “central oscillator,” demonstrated

- located predominantly in cerebellum and brainstem

- but other areas seem to be involved in this circuit

- creating a ponto-cerebello-thalamo-motor cortical activation

- differential diagnoses for a 10-year-old dog with chronic standing tremors

(and difficulty lying down)

- OTs

- benign idiopathic rapid postural tremors

- these appear in older dogs

- not associated with any type of difficulty in lying down

- usually do not disappear with a weight-bearing lifting test

- tremors due to paresis as a consequence of a neuromuscular disease

- causing exercise intolerance and weakness

- neuromuscular disease unlikely

- since evaluation of spinal reflexes was unremarkable

- degenerative lumbosacral stenosis causing cauda equina compression

- degenerative lumbosacral stenosis ruled out due to the following:

- unremarkable lumbosacral area palpation

- unremarkable perineal reflex

- unremarkable extension of the lumbosacral joint

(also called “lordosis test”)

- sciatic nerve malfunction

- chronic orthopedic problems such as hip dysplasia

- CBC and serum biochemistry results considered not clinically relevant

- leukopenia, slight at 4.39 thousands/μL with reference at 5.49-8.23

- high ferritin, mild at 302 ng/mL with reference at 84-247

- hypercholesterolemia at 339 mg/dL with reference at 151-249

- orthopedic examination: unremarkable

- conscious surface electromyography (EMG) of affected limb muscles

- OTs are characterized by pathognomonic high-frequency tremors

- during a standing position

- high-frequency rhythmic spontaneous discharges of 20 Hz recorded

- in all tested limbs

- definitive diagnosis: primary OTs

- treatment

- trial with gabapentin, 3 mg/kg PO bid started

- slowly increased to 5 mg/kg bid

- owner reported no improvement after 3 months of therapy

- dog started showing drowsiness

- owner declined other medical options and gabapentin was stopped

- outcome after 1 year followup, clinical signs unchanged

“The overall prognosis in dogs with OTs is considered to be good, as the disease is benign and slowly progressive.”

Article Tools:

Medline

Email to me

Archives Highlights:

"Do Your Homework as Your Heart Takes over When You Go Looking": Factors Associated with Pre-Acquisition Information-Seeking among Prospective UK Dog Owners.
Of potential owners, 68% reported already having looked for information, while a further 14% were planning to undertake research prior to acquiring a dog. Those with previous dog ownership experience were less likely to undertake pre-acquisition research, as were those who had worked with dogs. Among current owners, pre-acquisition research was more likely among those who acquired their dog through a breeder; a specific breed or a mix of two breeds; or as a puppy.

Understanding the Role of Therapy Dogs in Human Health Promotion.
Therapy dog programmes are delivered across a variety of settings including hospitals, aged care facilities and mental health services, highlighting the important role they play in human health outcomes. Research has shown that that there are biomarkers for stress in humans and other animals engaged in human-animal interactions. This review aims to assess the impact of human-animal interactions on therapy dogs engaged in providing support to human health.

Difficulty walking and trembling in a 10-year-old female Akita Inu.
The overall prognosis in dogs with orthostatic tremors is considered to be good, as the disease is benign and slowly progressive.

Role of autopsy imaging in veterinary forensic medicine: experiences in 39 cases.
Among the 39 cases, 28, 6, 3, 1, and 1 involved cats, dogs, rabbits, a ferret, and a pigeon, respectively. The major autopsy imaging (Ai) findings included skull and rib fractures, subcutaneous emphysema, pneumothorax, pneumoperitoneum, diaphragmatic hernia, and abdominal rupture. The leading causes of death, determined comprehensively via Ai and pathological reports and drug test results, included traumatic impact, blood loss, poisoning, suffocation, tension pneumothorax, starvation, and drowning, all of which have been strongly suspected to indicate animal abuse by humans.

Risk factors for unilateral cranial cruciate ligament rupture diagnosis and for clinical management in dogs under primary veterinary care in the UK.
After accounting for confounding factors, dogs aged 6 to less than 9 years, male neutered and female neutered dogs, insured dogs, and Rottweiler, Bichon Frise, and West Highland White terrier breeds, in particular, had increased odds of unilateral CCL rupture diagnosis. Insured dogs and dogs = 20 kg had increased odds of surgical management, while dogs = 9 years and dogs with one non-orthopaedic comorbidity at diagnosis with CCL rupture had reduced odds. These findings inform identification of at-risk dogs.