Headshaking in horses is a condition characterized by involuntary, repetitive movements of the head, often described as shaking, flicking, or jerking motions. This behavior can occur spontaneously and is sometimes associated with specific triggers such as light, sound, or exercise. The underlying causes of headshaking are not fully understood but may involve neuropathic pain, particularly related to the trigeminal nerve. The condition can affect a horse's quality of life and performance. Various diagnostic approaches are employed to identify potential causes, and management strategies may include environmental modifications, medical treatments, and protective gear. This page compiles peer-reviewed research studies and scholarly articles that explore the etiology, diagnosis, and management of headshaking in horses.
Pickles KJ, Gibson TJ, Johnson CB, Walsh V, Murrell JC, Madigan JE.The aim of this study was to develop a technique for recording electrical activity of the equine cerebral cortex following application of a noxious electrical stimulus to the maxillary branch of the trigeminal nerve in order to investigate trigeminal nerve neurophysiology in control and headshaking horses. Triphasic somatosensory evoked potentials (SEPs) were recorded using subcutaneous needle electrodes in four control and four headshaking horses under general anaesthesia. Dural electroencephalography electrodes were used to record SEPs in one further control and one further headshaking horse...
Pickles KJ, Berger J, Davies R, Roser J, Madigan JE.The aim of this study was to investigate the use of a gonadotrophin-releasing hormone (GnRH) vaccine in the treatment of headshaking in horses. Fifteen geldings received two doses of the GnRH vaccine four weeks apart. Serum was collected before and after vaccination to measure concentrations of luteinising hormone (LH) (10 horses) and follicle-stimulating hormone (FSH) (six horses). Owners recorded the frequency of seven common headshaking behaviours using a visual analogue scale (VAS) before vaccination and at two, four, eight, 12, 16 and 20 weeks after vaccination. Serum LH (P=0.008) and FSH...
Hessler C, Schilling B, Meenen NM, Lockemann U, Püschel K.Equitation is associated with a high rate of injuries and lethal accidents. The head is the most frequently concerned body part. Hence in the majority of the cases deaths results from head injuries. In this study injuries as well as causes of deaths were analyzed in 21 cases. Actual safety standards in equitation were appraised and suggestions for improvement were formulated. Methods: Between 1996 and 2008 21 equestrians suffered from a fatal accident in the greater area of Hamburg. In a retrospective analysis, equestrians' records which bases on the documentation of the institute of forensic ...
Mathie RT, Baitson ES, Hansen L, Elliott MF, Hoare J.Twelve Faculty of Homeopathy veterinarians recorded data systematically at 777 consecutive homeopathic appointments for horses over a period of 12 months. A spreadsheet enabled the recording of information, which included the date of appointment; horse and owner identity (anonymised); sex of horse; main medical problem treated; whether the condition was chronic or acute; whether the appointment was new or a follow-up; owner-assessed clinical outcome on a seven-point scale, ranging from -3 to +3, compared with the first appointment; homeopathic medicine(s) prescribed; and whether any convention...
Voigt A, Saulez MN, Donnellan CM.The medical records of 2 Thoroughbred horses that developed headshaking after blunt trauma to the occipital region are reviewed. The history, signalment, clinical signs, diagnostic methods, diagnosis and treatment were recorded in each case. Both horses displayed headshaking, while one horse repeatedly lifted its upper lip and pawed excessively at the ground. In both horses, diagnostic imaging of the occipital region revealed avulsion fragments of the nuchal crest and a nuchal desmitis in association with hyperfibrinogenaemia. The presence of an avulsion fragment of the nuchal crest with assoc...
Roberts VL, McKane SA, Williams A, Knottenbelt DC.REASONS FOR DESIGNING AND REPORTING TECHNIQUE: Idiopathic headshaking has remarkable similarities to human neuropathic facial pain syndromes associated with post herpetic and trigeminal neuralgia. These derive from abnormal sensory function within the peripheral or central pathways of the trigeminal nerve (TgN). Limiting input from the TgN can be helpful in controlling the perception of pain. Rhizotomy of the infraorbital branch of the TgN as it emerges from the infraorbital canal has been reported but has a poor efficacy. A novel technique involves compression of the nerve at a more caudal lo...
Schwarz BC, Sallmutter T, Nell B.A 6-year-old 680-kg (1,496-lb) German Warmblood gelding was evaluated because of bilateral blepharospasm and head shaking. Results: Moderate blepharospasm was evident bilaterally, and both eyes had hyperemic and edematous conjunctivas and lusterless corneas. For each eye, the Schirmer tear test value was only 7 mm/min. The horse's nasal mucosa was dry. Abnormal behaviors included mild repetitive vertical movement of the head, snorting, and flehmen response (classic signs of head shaking). Touching the horse's nostrils and face revealed paresthesia and dysesthesia with slight nasolabial muscle ...
Berger JM, Bell SA, Holmberg BJ, Madigan JE.A 15-year-old Saddlebred gelding used for competitive pleasure driving had a 1-year history of head shaking while pulling a cart. Results: The horse had cystic corpora nigra in both eyes and concomitant classic and operant conditioned responses to wearing a bridle with bilateral eye covers (blinkers). Results: Deflation and coagulation of the cysts with an infrared diode laser and behavior modification consisting of desensitization and counter-conditioning were used to successfully restore performance. Conclusions: Behavioral changes in horses can result from a combination of physical and psyc...
Barber SM.The horse, a flight animal that is used extensively by man, frequently receives injuries to its neck or head that result mostly from its management and handling. Better facilities, training of the horse, and horsemanship skills of the handler could prevent many of these injuries. Because many body systems can be involved, with potentially major consequences regarding health, performance, and appearance, early recognition of trauma and competent treatment are crucial. Progress has been made in the treatment of some tracheal and esophageal injuries. Severe tracheal trauma and rupture of the esop...
Bell AJ.A 10-year-old Thoroughbred mare was presented with a 2.5-week history of headshaking. Based on a thorough physical examination, blood analysis, and a fine needle aspirate of an enlarged thyroid gland, a tentative diagnosis of seasonal idiopathic headshaking was made. Treatment with cyproheptadine was attempted. Une jument Thoroughbred âgée de 10 ans a été présentée pour un problème d’encensement qui durait depuis 2.5 semaines. Suite à un examen physique méticuleux, à une analyse de sang et à un prélèvement par aspiration à l’aiguille de la glande thyroïde hypertrophiée, un...
Mills DS, Taylor K.Thirty-six owners of seasonally headshaking horses took part in a trial to compare the effectiveness of three types of nose net, a traditional cylindrical net (full net) and two forms of larger mesh nets which cover only the nostrils and dorsorostral muzzle (half nets). Baseline data relating to the overall severity of the problem and 18 specific behaviours describing the nature of the problem were recorded on a check sheet by the owners. A within-subjects repeated measures design experiment, with each net used for a week before reassessment, was then used to assess the effect of the nets on t...
Moss PS, Wan A, Whitlock MR.To describe the demographics and nature of injuries occurring on or around horses, to examine the nature of protective clothing in relation to these injuries, and to compare our data with previously published work in this area. Methods: Patients were identified using the term "sports injury-horse riding" from the departmental database for one calendar year from February 2000. Data were collected regarding demographics, injuries, protective clothing, and outcome. The data were then analysed and compared with the previously published literature. Results: 260 patients' records were analysed. The ...
Mills DS, Cook S, Taylor K, Jones B.A national survey of headshaking in 254 horses was undertaken to describe the clinical signs of the condition as observed by horse owners. Principal component analysis was used to determine the underlying structure of 11 signs and the criteria by which the affected horses could be most effectively differentiated; the analysis suggested five components with a variance greater than one which together explained over 60 per cent of the total variance. Other analyses of the data indicated that headshaking could develop at any age and that twice as many males were affected as females; 64 per cent of...
Madigan JE, Bell SA.To determine signalment, history, clinical signs, duration, seasonality, and response to various treatments reported by owners for headshaking in horses. Methods: Owner survey. Methods: 109 horses with headshaking. Methods: Owners of affected horses completed a survey questionnaire. Results: 78 affected horses were geldings, 29 were mares, and 2 were stallions. Mean age of onset was 9 years. Headshaking in 64 horses had a seasonal component, and for most horses, headshaking began in spring and ceased in late summer or fall. The most common clinical signs were shaking the head in a vertical pla...
Newton SA, Knottenbelt DC, Eldridge PR.Twenty mature horses with typical headshaking of 2 week-7 year duration were studied. Clinical examinations included radiography of the head and nasopharyngeal endoscopy. All were assessed at rest and at exercise, both before and after fitting an occlusive nasal mask, application of tinted contact lenses and the perineural anaesthesia of the infraorbital and posterior ethmoidal branches of the trigeminal nerve. Infraorbital anaesthesia had no effect in 6/7 cases but 11/17 (65%) cases showed a 90-100% improvement following posterior ethmoidal nerve anaesthesia. Tinted contact lenses had no appa...
Madigan JE, Bell SA.Headshaking is a maturity onset condition with the most commonly reported clinical signs being 'flipping' of the nose, nose rubbing, snorting or sneezing, and acting like a bee is flying up the nostril. A questionnaire was completed by owners of 31 horses with headshaking syndrome. The history, time of onset, clinical presentation and treatment of this condition were reported. Headshaking appeared to be light-stimulated in approximately 60% of the horses. The condition is seasonal and recurring in the majority of horses. Treatment with cyproheptadine produced improvement of symptoms in 76% of ...
Moore LA, Johnson PJ, Messer NT, Kline KL, Crump LM, Knibb JR.Unlike the incidence of equine protozoal myeloencephalitis (EPM), which appears to be increasing, headshaking is an uncommon problem for horses in Missouri and the adjacent states. Equine protozoal myeloencephalitis was incriminated in three horses examined for the treatment of headshaking on the basis of a neurological examination, an analysis of cerebrospinal fluid and their response to treatment. The headshaking and stereotypical behaviour associated with EPM was successfully treated with potentiated sulphonamides and pyrimethamine.
Blythe LL.Otitis media/interna in the equine most commonly is a chronic, insidious infection with the unique sequella of temporohyoid osteoarthropathy in some horses. Head shaking may be the only clinical sign of the early stages of this disease. The arthritic condition often leads to fusion of the temporohyoid joint with resultant stress fractures of the petrous temporal bone. When this occurs, the horse presents as an acute neurologic case with clinical signs of vestibular and facial nerve dysfunction. Diagnosis, treatment, and prognosis are discussed. Recognition of this syndrome is important because...
Hassel DM, Schott HC, Tucker RL, Hines MT.Endoscopic examination of the auditory tube diverticula was a diagnostic aid in the evaluation of 4 horses with otitis media/interna and associated osseous changes of the stylohyoid and petrous temporal. One of the horses was examined because of persistent head shaking; the other 3 were examined because of an acute onset of facial and vestibulocochlear nerve dysfunction. Proliferative lesions involving the petrous temporal bone and proximal portion of the stylohyoid bone were identified endoscopically in all 4 horses. Endoscopy is a noninvasive procedure that provides an alternative to skull r...
Madigan JE, Kortz G, Murphy C, Rodger L.Seven horses with headshaking are described. No physical abnormalities were detected in any of the cases. Six of these horses had onset of clinical signs in the spring. The role of light was assessed by application of a blindfold or dark grey lens to the eyes, covering the eyes with a face mask and observing the horse in total darkness outdoors. Cessation of headshaking was observed with blindfolding (5/5 horses), night darkness outdoors (4/4 horses) and use of grey lenses (2/3 horses). Outdoor behaviour suggested efforts to avoid light in 4/4 cases. The photic sneeze in man is suggested as a ...
Fletcher J, Davies PT, Lewis T, Campbell MJ.Jockeys accept bony fractures and soft tissue injuries as occupational hazards. An average National Hunt jockey falls once in ten races with an injury rate of 4.25%. Head injury is a common cause of morbidity and the benefit of helmets is well recognized. Neck injuries are also common and usually musculoskeletal. Although rare, trauma to the neck arteries may go unnoticed yet have catastrophic consequences. Internal tears can allow arterial blood to dissect the layers of the arterial wall and obstruct the lumen. Severe obstruction may lead to cerebral ischaemia and infarction. An appreciation ...
Mair TS, Howarth S, Lane JG.Eighteen horses affected by the idiopathic headshaker syndrome were studied in an owner assessed trial to test the efficacy of some prophylactic therapies. Riding the affected animal with a veil over the nostrils gave varying degrees of temporary relief in three of 10 horses. Local (intra-nasal) corticosteroid therapy was reported to be slightly effective in three of nine horses, but treatment with sodium cromoglycate, systemic corticosteroid, flunixin meglumine and an antihistamine were generally ineffective. Bilateral infraorbital neurectomy provided sustained relief in three of seven horses...
Sinha AK, Hendrickson DA, Kannegieter NJ.The initial clinical signs displayed by two horses with head trauma are described and related to the pathology and management of the condition, to illustrate the diversity of signs that may result from similar events. It is suggested that careful repeated neurological investigations are more reliable prognostic indicators in cases of equine head trauma than a reliance on the initial assessment.
Carter BT, Richardson MD.The aim of the study was to examine helmet use, incidence of injury, and patient outcomes in a rural cohort of equestrian accidents. Unassigned: EHR records of patients admitted to a Level II ACS trauma center in the North-west United States were reviewed for helmet use. Injuries were categorized according to International Classification of Diseases-9/10 code. Unassigned: Of 53 identified cases, helmets only reduced superficial injury (χ (1) = 4.837, = 0.028). Intracranial injury rates were not different between those with and without helmets ( > 0.05). Unassigned: In equine related injur...
ten Kate CA, de Kooter TA, Kramer W.Each year 9,900 equestrians present at Accident and Emergency Departments, 40% of them 10-19 year old females. The most common horse-riding injuries are to the head, brain, neck and face, torso and extremities. Because of the relatively larger head, children more often fall on their head. Wearing a helmet gives considerable protection. Despite the common use of a helmet by horseback riders, serious head injury still occurs regularly. Further research into improvement of the protective function of the helmet is indicated. The current safety vest (body protector) does not significantly reduce th...
Schwarz B, Klang A, Schwendenwein I.A 14-year-old Zweibrücker Warmblood gelding was presented for evaluation of lethargy and headshaking. The horse had a history of bouts of lameness in different limbs and back problems. It also had many mild colic episodes in the past. Results of repeat laboratory tests had shown persistent hypercalcemia (4.8 mmol/L; reference interval [RI]: 2.0-3.2 mmol/L) for 1.5 years and later on hypophosphatemia (0.4 mmol/L; RI: 0.5-1.3 mmol/L) and mild hypermagnesemia (1.0 mmol/L; RI: 0.5-0.9 mmol/L). Parathyroid hormone (PTH) concentration was within the RI. Other causes of hypercalcemia, such as...
Reich L.Horses' kicks can produce two types of head and neck injuries: injuries of the mid-face and injuries of the larynx. Typical cases as seen by the author are presented. The treatment of mid-face injuries is performed according to principles of plastic surgical repair. After frontal-nasal injuries, a revision of the nasal septum must be done. Involvement of the larynx requires external layer repair of mucosa and cartilage.
Labbe KA, Allshouse KA, Gilmour LJ, Arnold CE, Whitfield-Cargile CM, Griffin CE.Sinusitis is a common disease of horses yet there are a limited number of reports in the literature that describe the prevalence of infraorbital canal (IOC) pathology and headshaking behaviour in horses diagnosed specifically with primary sinusitis and secondary dental sinusitis. Given the impact that these behaviours can have on horses' intended athletic use, investigation is warranted. Objective: To determine the occurrence of IOC pathology in horses with concurrent primary or secondary dental sinusitis based on computed tomography (CT) findings and to assess whether the frequency of headsha...
Parry BW, Gay CC, McCarthy MA.Eighteen horses were used to investigate the influence of head position on arterial blood pressure, measured indirectly at the coccygeal artery. Head height significantly altered systolic pressure, diastolic pressure, pulse pressure, and mean arterial pressure, such that head-lowering decreased and head-raising increased all variables.
Mathie RT, Baitson ES, Hansen L, Elliott MF, Hoare J.Twelve Faculty of Homeopathy veterinarians recorded data systematically at 777 consecutive homeopathic appointments for horses over a period of 12 months. A spreadsheet enabled the recording of information, which included the date of appointment; horse and owner identity (anonymised); sex of horse; main medical problem treated; whether the condition was chronic or acute; whether the appointment was new or a follow-up; owner-assessed clinical outcome on a seven-point scale, ranging from -3 to +3, compared with the first appointment; homeopathic medicine(s) prescribed; and whether any convention...
Lim CK, Saulez MN, Viljoen A, Carstens A.A two-year-old Thoroughbred colt was presented to the Equine Clinic, Onderstepoort Veterinary Academic Hospital for head trauma after rearing and falling backwards, hitting his head on the ground. Following medical therapy for acute onset neurological impairment secondary to a suspected basilar skull fracture, the horse was anaesthetised and computed tomography of the skull was performed. A diagnosis of a comminuted basilar skull fracture was made and skull radiographs were taken for comparison. The horse was subsequently euthanased owing to the poor prognosis; necropsy findings were compatibl...
Blanke A, Fischer ML, Fuchs M, Schusser GF.Since there is a lack of information about the normal appearance or pathological findings of the equine external ear canal (EEEC) and tympanic membrane (TM), we aimed to find a practical way to perform the otoscopic examination in standing, sedated horses. Therefore, we worked with common veterinary video endoscopes, which are normally used for gastroscopy or bronchoscopy. Both ears each of 38 randomly selected, chemically restrained horses were otoscopically examined. 33 of those horses had no history or signs of potentially ear-associated diseases. However, two horses with vestibular disease...
Barber SM.The horse, a flight animal that is used extensively by man, frequently receives injuries to its neck or head that result mostly from its management and handling. Better facilities, training of the horse, and horsemanship skills of the handler could prevent many of these injuries. Because many body systems can be involved, with potentially major consequences regarding health, performance, and appearance, early recognition of trauma and competent treatment are crucial. Progress has been made in the treatment of some tracheal and esophageal injuries. Severe tracheal trauma and rupture of the esop...
Toft K, Kjeldsen ST, Otten ND, van Galen G, Fjeldborg J, Sinding M, Hansen S.Flexion of the horse's head and neck during dressage riding reduces the pharyngeal lumen with the risk of increased upper airway resistance and upper airway obstructions. According to the Fédération Equestre Internationale, hyperflexion is achieved through force, whereas the position low-deep-round is nonforced. The objectives of this study were to evaluate (1) applied rein tension and (2) dynamic structural disorders in the upper airways in dressage horses in different gaits and different head-neck positions (HNPs). Overground endoscopy (OGE) and rein tension were evaluated in 13 clinically...
Kloock T, Hellige M, Kloock A, Feige K, Niebuhr T.Horses with trigeminal-mediated headshaking (TMHS) exhibit different headshaking patterns (HSPs), electric shock-like jerking, signs of nasal irritation, and painful facial expressions. The History Rest and Exercise Score (HRE-S) was developed to objectively clarify the severity of the condition in affected horses. This score considers the history and severity of clinical signs at rest and exercise. This study aimed to assess the frequency of different clinical signs and their individual associations with diagnosis, treatment, and outcome in horses diagnosed with TMHS.The clinical records of h...
Nessler JN, Delarocque J, Kloock T, Twele L, Neudeck S, Meyerhoff N, Riese F, Cavalleri JV, Tipold A, Feige K, Niebuhr T.To determine whether sensory nerve conduction stimulus threshold measurements of the infraorbital nerve are able to differentiate horses with idiopathic trigeminal-mediated headshaking (i-TMHS) from healthy horses and from horses with secondary trigeminal-mediated headshaking (s-TMHS). In a prospective trial, headshaking horses were examined using a standardized diagnostic protocol, including advanced diagnostics such as computed tomography and 3-Tesla-magnetic resonance imaging (MRI), to differentiate s-TMHS from i-TMHS. Clinically healthy horses served as controls. Within this process, patie...
Franzen V, Reisbeck D, Leibl Y, Schoster A, May A.While there is agreement that horses experience pain during the actual headshaking attacks, there is still a lack of research about the time between the individual episodes in this species. Objective: To evaluate the signs of pain in horses with TMHS at rest in the absence of common triggering factors. Methods: Twenty TMHS horses (not head shaking at the time of pain assessment), 20 horses with colic, and 20 clinically healthy horses. Methods: Descriptive study assessing pain in TMHS horses during the absence of clinical signs using the Horse Grimace scale (HGS). To grade the pain shown with T...
Lloyd-Edwards RA, Mulders E, Sloet van Oldruitenborgh-Oosterbaan MM, Veraa S. Headshaking is a common condition in horses, most cases are presumed idiopathic/trigeminal-nerve mediated. Diagnostic work-up of a headshaking horse may involve computed tomography (CT) of the head to exclude causative structural pathology. The relevance of the presence and severity of hyoid apparatus findings at CT to headshaking is unknown. A retrospective analysis of CT changes in the hyoid apparatus in horses was carried out. Comparisons were performed between horses with signs of headshaking and a control population and a subgroup of horses with signs of headshaking and no other 'likely...
de Preux M, Precht C, Becker R, Stieglitz L, Easley J, Koch C.Trigeminal-mediated headshaking is a neuropathic disorder in horses, characterized by signs of regional pain similar to trigeminal neuralgia in humans. The injection of glycerol into the trigeminal cistern to ablate pain-conducting nerve fibers within the trigeminal ganglion -known as glycerol rhizotomy- is a well-established treatment in human medicine. This study compares two approaches to the equine trigeminal cistern using a navigation system for guiding needle placement, a previously described ventral and a newly developed transmandibular lateral approach. The surgical accuracy and risk o...
Gerring EL, Thomsett LR.It is reported that in Australia, the finding of Psoroptes cuniculi (Delafond) (including its synonym P. hippotis Raill. & Henry) in the ears of head-shaking horses is relatively common among thoroughbred racing horses in southern Queensland. A survey of the ears of horses undergoing theatre surgery showed that about 20% of the horses were infested.
McCarthy PH.A detailed description is given of the structures forming the borders of Viborg's triangle and those structures contained within and adjacent to the triangle. Changes in the size, shape and prominence of these structures with changes of head and neck posture of the horse are also described.
Paulussen E, Decloedt A, Vera L, Lefere L, van Loon G.Venous stenosis, a possible cause of jugular dilatation and congestion, is well known in human medicine but has poorly been described in horses. Objective: To report unilateral jugular vein stenosis as a cause of jugular vein dilatation in horses and describe treatment by percutaneous transluminal angioplasty (PTA). Methods: Case report. Methods: Details of horses diagnosed with unilateral jugular stenosis were retrieved from medical records. Results: Five horses were presented with a non-painful, unilateral dilatation of the jugular vein of which two horses showed headshaking during exercise....
Sinha AK, Hendrickson DA, Kannegieter NJ.The initial clinical signs displayed by two horses with head trauma are described and related to the pathology and management of the condition, to illustrate the diversity of signs that may result from similar events. It is suggested that careful repeated neurological investigations are more reliable prognostic indicators in cases of equine head trauma than a reliance on the initial assessment.
Clark JM, Connor TA, Post A, Hoshizaki TB, Gilchrist MD.Current equestrian standards employ a drop test to a rigid steel anvil. However, falls in equestrian sports often result in impacts with soft ground. The purpose of this study was to compare head kinematics and brain tissue response associated with surfaces impacted during equestrian accidents and corresponding helmet certification tests. A helmeted Hybrid III headform was dropped freely onto three different anvils (steel, turf and sand) at three impact locations. Peak linear acceleration, rotational acceleration and impact duration of the headform were measured. Resulting accelerations served...
Mattacola CG, Quintana C, Crots J, Tumlin KI, Bonin S. During thoroughbred races, jockeys are placed in potentially injurious situations, often with inadequate safety equipment. Jockeys frequently sustain head injuries; therefore, it is important that they wear appropriately certified helmets. The goals of this study are (1) to perform impact attenuation testing according to ASTM F1163-15 on a sample of equestrian helmets commonly used by jockeys in the United States and (2) to quantify headform acceleration and residual crush after repeat impacts at the same location. Seven helmet models underwent impact attenuation testing according to ASTM...
Bell T, Kyriazopoulou P, Mowbray C, Murphy BA.Equine headshaking syndrome is a poorly understood neuropathic pain condition presenting as uncontrollable shaking, flicking, or striking of the head. Therapeutic options are limited, and treatments are only partially successful. Currently, epidemiological information on headshaking in the Southern Hemisphere is lacking. An online survey was circulated to Australian owners of headshaking horses to collect information on triggers, symptoms, seasonality, treatments, and perceived treatment efficacy. The responses (n = 216) showed the mean age at symptom onset as 9.6 (±4.7) years. More geldings ...
