What causes equine ataxia? By far the most common cause of ataxia in horses is spinal cord compressionand, in particular, in the neck – so-called wobblers syndrome or cervical vertebral malformation / malarticulation (CVM). It is unknown exactly how common compression of the spinal cord in the neck is.
What is ataxia in horses?
That being said, Hahn recommends going back to the basics to truly understand what ataxia is and how to diagnose the cause for ataxia in affected horses. "Ataxia is a Greek term that means inconsistent," said Hahn. "Ataxic horses are those that are unable to control the rate, range, or force of their movements resulting in an inconsistent gait."
Can a horse be ataxic before a fall?
In many instances, the horse was mildly ataxic before the traumatic episode, and the mild neurologic deficits may even have been a predisposing cause of the fall. The traumatic incident exacerbates the neurologic signs because of cord swelling within the stenotic vertebral column.
What is trauma-induced ataxia?
Trauma-Induced Ataxia. Trauma to the brain most commonly occurs when a horse rears up and flips over backwards, hitting the back of his head on the ground. It can also happen if a horse rears up when loading into a trailer or in a barn with a low ceiling.
What causes ataxia in cervical vertebral malformation?
Cervical vertebral malformation CVM/instability (CVI) or wobblers syndrome causes ataxia, usually of all four limbs, through compression of the spinal cord by the cervical vertebrae of the neck.
What does ataxia look like in horses?
In addition to not being able to control limb movements appropriately, the horse is unable to control head and neck movements. This lack of control leads to head and neck tremors, which are often worsened by intentional movements, as when the horse lowers or raises its head to eat.
Can horses with ataxia be ridden?
In Europe if the horse is found to be ataxic, which is most often due to the disease 'wobbler syndrome', the horse is likely to be put down immediately. If a horse suffers from this disease, putting it down can be a necessity, as the animal can be dangerous to ride and handle.
What are two differentials for weakness and ataxia in a horse?
That is to say, in a horse with weakness, ataxia and spasticity of all four limbs with no muscle atrophy or cranial nerve deficits, the horse may have cervical vertebral stenotic myelopathy or equine degenerative myeloencephalopathy.
What are signs of EPM in horses?
Many of the EPM signs mimic other neurologic disease or may come and go.Incoordination; stiff, stilted movements; abnormal gait or lameness.Incoordination and weakness. ... Muscle atrophy. ... Drooping eyes, ears or lips.Difficulty swallowing.Seizures or collapse.Abnormal sweating.Loss of feeling along the face, neck or body.More items...
What are signs of neurological problems in horses?
Neurologic signs often include ascending paralysis with urine dribbling, loss of anal tone and control, poor tail tone, and pelvic limb weakness. Diagnosis of EHM is easier to establish when several horses on the same premises present with fever, followed by ataxia and urine dribbling and in some cases abortion.
What causes a horse to be unsteady on their feet?
The causes are numerous and include trauma, spinal cord tumor, back pain, metabolic disease, vertebral abscess, toxic exposure, parasite migration, nutritional imbalances, degenerative joint disease, malnutrition, or infectious disease.
Can Cushings in horses cause neurological problems?
In a horse with Cushing's, the brain is enlarged, and the resulting hormone imbalance can affect the adrenal glands and the kidneys. The failure of these systems can cause a horse to develop chronic infections, which can also, in some cases, lead to neurological conditions.
Can wobblers in horses be cured?
Contact your veterinarian if you suspect your horse has developed wobbler syndrome or any other neurological disease. Horses with this syndrome can be treated with drug therapy, surgery, or aggressive management.
What is meant by ataxia?
Ataxia describes poor muscle control that causes clumsy voluntary movements. It may cause difficulty with walking and balance, hand coordination, speech and swallowing, and eye movements. Ataxia usually results from damage to the part of the brain that controls muscle coordination (cerebellum) or its connections.
Can a horse fully recover from EPM?
If left undiagnosed and untreated, EPM can cause devastating and lasting neurological deficits. The success rate for treated horses is high. Many will improve and a smaller percentage will recover completely, but 10-20% of cases may relapse within two years.
Are horses in pain with EPM?
EPM can impact both the brain and spinal cord, so symptoms can vary from case to case. Pain caused by EPM lesions may also cause a horse to become grouchy.
What animals transmit EPM to horses?
The disease is not transmitted from horse to horse. Rather, the protozoa are spread by the definitive host, the opossum, which acquires the organism from cats, raccoons, skunks and armadillos and possibly even from harbor seals and sea otters.
What is meant by ataxia?
Ataxia describes poor muscle control that causes clumsy voluntary movements. It may cause difficulty with walking and balance, hand coordination, speech and swallowing, and eye movements. Ataxia usually results from damage to the part of the brain that controls muscle coordination (cerebellum) or its connections.
What is ehm horse?
Equine herpesvirus myeloencephalopathy (EHM) is another name for the neurologic disease associated with equine herpesvirus (EHV) infec- tions. Neurological signs appear as a result of damage to blood vessels in the brain and spinal cord associated with EHV infection.
How do you test a horse for wobblers?
Turning the horse in a small circle is a quick and easy test to detect wobbler syndrome. A horse suffering from the syndrome will swing the rear legs out while making the turn. The horse also will have trouble backing up.
Why does my horse have spinal ataxia?
Certain vertebras in the area of the cervical vertebrae can easily crick and press on the spinal cord. This pressure increases if the horse lowers his head.
How to treat spinal ataxia in horses?
In case of a spinal Ataxia vet and horse owner can work out an individual therapy program. The medicinal therapy is based on anti-inflammatory medicine like antibiotics, antiserums and possibly antiparasitics. Moreover it can be very helpful to feed additional Selenium and vitamin E. These two elements support the neck muscles and therefore help to relieve the cervical vertebrae. In case of a surgery the vertebras get stiffen so that they cannot press on the nerve fibers anymore. This surgery is very painful and limits the general mobility of the horse – and no one is able to guarantee that the horse will be able to control his legs afterwards. All these doubts already lead to many discussions about this surgery. The horse owner should try to find the best way for the horse – and should not forget that horses are powerful animals that love to move and run.
What is Ataxia?
Ataxia is a dysfunction of the central nervous system that is the spinal cord and the brain. This dysfunction can have many different origins. The vertebral column is made out of the spinal canal and the spinal cord (inside of the spinal canal). The nerves of the spinal cord are the “information channels” of the whole organism: The commands of the brain get transported by these nerve fibers so that they can reach the respective part of the body. In case of an Ataxia this communication between the brain and the rest of the body is disturbed. The horse loses his feeling for his hoof and is not able to place it to the front, back or side. Instead he only realizes that his hoof already is on the ground when he feels the pressure coming up his leg. If you watch a horse with Ataxia you can clearly see how it has great problems to coordinate his movements.
What causes brain damage in horses?
In most cases the damage of the brain is caused by viral and bacterial infections (this can be compared with the so called meningitis of humans). The most dangerous origin also is the most often one: Equine Herpes Virus. The virus causes swellings and inflammations in the brain and this leads to a bruise of the nerve fibers. The commands of the brain cannot get transmitted via the spinal cord to the muscles: The horse is nearly paralyzed! An infection with the dangerous borrelia burgdorferi bacteria has the same effects. They can cause an Equine Borreliosis what means dangerous inflammations in the brain. Further potential origins are a parasite infestation (they can spread from the brain into the entire spinal cord) as well as very dangerous intoxications (toxic substances especially attack nerve fibers.)
Why is my horse limping?
Regularly experts and vets warn horse owners not to diagnose Ataxia as soon as their horses walk in an irregular way. There are many possible origins for a limping horse: a simple sprain or even a laminitis. However it is crucial that horse owners contact a vet as soon as they first notice a stumbling walk.
What are the different types of ataxia?
In general there are three different types of ataxia: spinal, cerebral and cerebellar Ataxia. Everyone who once saw a horse with Ataxia understands the name of this disease: the Greek word ataxia stands for “lack of order” – and that is exactly how the movements of the horse can be described. The hind legs hit in several directions and ...
What is the name of the condition in which horses walk uncontrolled?
A staggering walk and uncontrolled movements: Horses with Ataxia. Uncontrolled legs that stumble or even break down: horses that suffer from ataxia have a lack of control over their legs. In general there are three different types of ataxia: spinal, cerebral and cerebellar Ataxia. Everyone who once saw a horse with Ataxia understands the name ...
What structure is commonly involved in an ataxic patient?
According to Hahn, "In order for the information to get to the cerebellum and forebrain the spinal cord has to be intact also, and this is a structure commonly involved in an ataxic patient."
What is ataxia in horses?
"Ataxia is a Greek term that means inconsistent," said Hahn. "Ataxic horses are those that are unable to control the rate, range, or force of their movements resulting in an inconsistent gait.".
Which part of the brain is responsible for proprioception?
This is called proprioception, and two regions of the brain are responsible for proper proprioception: the forebrain and the cerebellum (at the base of the brain).
Who is Stacey Oke?
Stacey Oke, MSc, DVM, is a practicing veterinarian and freelance medical writer and editor. She is interested in both large and small animals, as well as complementary and alternative medicine. Since 2005, she's worked as a research consultant for nutritional supplement companies, assisted physicians and veterinarians in publishing research articles and textbooks, and written for a number of educational magazines and websites.
SIGNAL PROBLEMS
CERTAIN developmental conditions present at birth can cause ataxia. These include abnormal underdevelopment of the cerebellum, called cerebellar abiotrophy, and abnormal formation of the first and second cervical vertebrae, termed atlantoaxial malformation.
RECOVERY CHANCES
THE prognosis for ataxia is variable, depending on the diagnosis. Stinging nettle-induced ataxia can resolve quickly and fully once the horse is removed from the nettles, sedated and provided with appropriate anti-inflammatories.
Suspended animation
DISTRESSING images and footage of horses affected by the recent outbreak of EHV-1 in Europe illustrate the neurological effects of this highly contagious disease.
What is vestibular ataxia?
Ataxia associated with vestibular disease is usually asymmetric, and usually strength is preserved. Ataxia results when the head does not orient with movement of the eyes, trunk, and limbs, resulting in loss of balance. Horses with vestibular ataxia lean, drift, or fall toward the side of the lesion and usually have ipsilateral head tilt combined with nystagmus. Vestibular lesions may be central or peripheral. Horses with signs of both vestibular ataxia and facial paralysis are most likely to have otitis or stylohyoid osteoarthropathy.
What is ataxia in the CNS?
Ataxia, or incoordination of gait, is frequently associated with concurrent clinical signs of spasticity (stiffness) and paresis (weakness) and may be a result of diffuse disease or a focal or multifocal lesion anywhere in the central nervous system (CNS ), including the cerebrum, cerebellum, brainstem, or spinal cord (Table 132-1). Cerebral, cerebellar, and brainstem lesions are uncommon but can result in ataxia in addition to other clinical signs referable to lesions in those areas. In this chapter, common conditions associated with ataxia are reviewed.
What is a CVSM horse?
Cervical vertebral stenotic myelopathy (CVSM) is also known as cervical vertebral malformation, cervical vertebral stenosis, cervical vertebral instability, and so-called wobbler syndrome. CVSM can develop in any horse at any age but is typically seen in young, fast-growing horses. The condition is most commonly reported in Thoroughbreds (up to 2%) and Quarter Horses and is more frequent in males than in females.
What causes vertebral stenotic myelopathy?
Cervical vertebral stenotic myelopathy may be a form of osteochondrosis involving the epiphyseal plate or articular processes. Vertebral instability leads to muscle and ligament hypertrophy, which can also lead to spinal cord compression. Prolonged compression or repetitive traumatic injury to the spinal cord initially results in damage to the peripheral white matter. The proprioceptive and spinocerebellar tracts of the pelvic limbs are positioned more superficially in the spinal cord than those of the thoracic limbs, which might explain why more severe ataxia is observed in the pelvic limbs compared with the thoracic limbs.
How to tell if a horse has cervical lesions?
Weakness can be evaluated subjectively by assessing the horse’s resistive strength and recovery of balance when the tail is pulled sharply to one side during walking. The tail should be pulled to both sides, and the timing of the tail pull should coincide with weight bearing on the ipsilateral hind limb. Sometimes the horse will stumble in attempts to correct its posture. Horses with a lesion high in the cervical portion of the spinal cord (C1-2) may also have a head tilt and may lean to one side, mimicking vestibular disease, although no pathologic nystagmus is present and no loss of balance is observed when the horse is blindfolded. A lesion in the thoracic intumescence (C6-T2) can cause ataxia of all four limbs, accompanied by lower motor signs of denervation atrophy, weakness, and possible paraesthesia of certain sensory cutaneous areas of the thoracic limbs. Clinical signs restricted to the pelvic limbs result from thoracolumbar lesions.
What causes a horse to be jerky?
Cerebellar disturbances result in ataxia and an inability to regulate the rate, range, and force of movement. Horses often have dysmetria; either hypermetria, with higher and longer flight of the limb, or hypometria. Initiation of movement may be jerky, and truncal sway is common. Spasticity caused by hypertonia results in stiff, jerky movements. Cerebellar lesions do not cause paresis, although hypotonia can make a horse appear weak or drag its toes. Intention tremor is obvious with severe diffuse cerebellar disease. Unilateral lesions result in signs ipsilateral to the lesion.
Can a young horse fall?
Young horses often manifest acute onset of ataxia or gait abnormalities, often associated with a fall. In many instances, the horse was mildly ataxic before the traumatic episode, and the mild neurologic deficits may even have been a predisposing cause of the fall. The traumatic incident exacerbates the neurologic signs because of cord swelling within the stenotic vertebral column.
What is EPM in neurology?
EPM can range in severity, from a mild gait abnormality to recumbency. Neuroanatomic location: Can vary. Classical descriptions include a multifocal distribution, which often includes spinal cord and brainstem (cranial nerve disease). However, it can present as a cervical vertebrae and with a focal distribution.
Why does my horse's neck hurt?
Older horses: May present with ataxia or predominately neck pain due to osteoarthritis of the articular facets of the vertebrae.
What age do horses have spinal cord compression?
Young horses are usually well feed and fast growing. Typical age at presentation is 1-2 years (but maybe older or younger). Older horses: May present with ataxia or predominately neck pain due to osteoarthritis ...
What is the sensitivity of a horse's CSF?
The sensitivity of specificity of the tests range from 68-100% . Clinical experience has proven this not to be the case. There are many reports of antibody in the CSF of clinically normal horses. This may occur due to iatrogenic blood contamination. Antibodies within plasma can cross through an intact blood-brain barrier and into the CSF. Therefore it is important to make sure that other neurologic diseases are ruled out before trying to interpret a positive test on CSF. There are several labs that offer immunodiagnostic testing for EPM.
What is the clinical diagnosis of EPM?
Diagnosis of EPM should include two facts: 1) the horse has clinical signs of neurological disease and 2) clinicians should rule out as many other diseases resulting in similar clinical signs. There must be signs of neurological disease that are consistent with EPM.
What is OAAM in medical terms?
Occipito-atalanto-axial Malformation (OAAM): is the most common. There are a number of variations of this disease, but the basic abnormality involves fusion of the atlas and the occiput and hypoplasia of the atlas and dens. .
How long does vitamin E help with spinal cord disease?
Early in course of disease vitamin E supplementation may improve clinical signs (6,000 IU/day) for at least 1-3 years. Congenital abnormalities of the spinal cord. Occipito-atalanto-axial Malformation (OAAM): is the most common.
What is the first sign of neurologic problems in horses?
A horse’s ability to chew and swallow also should be checked. The first signs of neurologic problems are often proprioceptive deficits —that is, evaluation of the horse’s awareness of where he is in space.
Why is physical examination important for neurology?
A thorough physical examination is critical in evaluating neurologic patients. For example, routinely obtained physical data such as body temperature can help a practitioner differentiate between acute infectious causes of neurologic disease. Similarly, evaluation of the horse’s limbs may help a practitioner distinguish between gait abnormalities due to soreness and those caused by proprioceptive deficits.
What are the symptoms of EPM in horses?
Typical signs of EPM include ataxia and asymmetric muscle atrophy. Diagnosis of EPM may not be easy. Blood tests indicate only that a horse has been exposed to the protozoan organism, but most exposed horses do not also develop clinical disease.
How to diagnose CVM in horses?
Accurate diagnosis of CVM is usually made with radiography and perhaps with myelography. In young horses, cervical vertebral abnormalities may be accompanied by abnormalities of the distal limbs (osteochondrosis).
What is the last function lost in neurologic conditions?
The loss of deep-pain sensation is the last function lost in neurologic conditions, and it typically carries a grave prognosis.
What is the first step in neurologic exam?
Neurologic exams commonly begin with evaluation of the cranial nerves. Moving a hand rapidly toward the eye typically elicits a blink—the menace response. Pupillary light reflexes and the pupil position should be evaluated.
How to tell if a horse has ataxia?
Signs of ataxia in affected horses include toe dragging, stumbling or an outward turning of the rear limbs. Commonly used neurologic tests include: Tail pull. A horse typically will resist being pulled to one side by his tail. Crossing the hind feet.
What is the term for a lack of coordination in the brain?
Cerebellum and brainstem. Persistent ataxia usually results from damage to the part of your brain that controls muscle coordination (cerebellum). Ataxia describes a lack of muscle control or coordination of voluntary movements, such as walking or picking up objects. A sign of an underlying condition, ataxia can affect various movements ...
What is the term for the loss of nerve cells in the cerebellum?
Damage, degeneration or loss of nerve cells in the part of your brain that controls muscle coordination (cerebellum), results in ataxia. Your cerebellum comprises two portions of folded tissue situated at the base of your brain near your brainstem. This area of the brain helps with balance as well as eye movements, swallowing and speech.
What is the name of the part of the brain that controls muscle coordination?
Open pop-up dialog box. Close. Cerebellum and brainstem. Cerebellum and brainstem. Persistent ataxia usually results from damage to the part of your brain that controls muscle coordination (cerebellum). Ataxia describes a lack of muscle control or coordination of voluntary movements, such as walking or picking up objects.
What is Friedreich's ataxia?
Friedreich's ataxia. This common hereditary ataxia involves damage to your cerebellum, spinal cord and peripheral nerves. Peripheral nerves carry signals from your brain and spinal cord to your muscles. In most cases, signs and symptoms appear well before age 25.
What is the most common type of ataxia?
Episodic ataxia (EA). There are eight recognized types of ataxia that are episodic rather than progressive — EA 1 through EA 7, plus late-onset episodic ataxia. EA 1 and EA 2 are the most common. EA 1 involves brief ataxic episodes that may last seconds or minutes. The episodes are triggered by stress, being startled or sudden movement, and often are associated with muscle twitching.
How long does chickenpox ataxia last?
It might appear in the healing stages of the infection and last for days or weeks. Normally, the ataxia resolves over time.
How to treat ataxia?
Adaptive devices, such as walkers or canes, might help you maintain your independence. Physical therapy, occupational therapy, speech therapy and regular aerobic exercise also might help .
