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.
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.
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.
McGorum BC, Dixon PM.VASOMOTOR rhinitis (VR) is a chronic, non-seasonal disease of the nasal mucosa of man with symptoms including profuse bilateral watery nasal discharge, sneezing, nasal airflow obstruction, nasal pruritus and loss of smell. The disease is believed to result from nasal hyper-reactivity to exogenous and endogenous stimuli including temperature and humidity changes, odours and physical or emotional stress (Groves, Gray, Downton and Blau 1985). Although the aetiology of this non-infectious and non-allergic rhinitis is not completely understood, it is believed to be largely due to an imbalance in th...
Lane JG, Mair TS.The clinical records of 100 cases of headshaking in horses were reviewed. Possible causes of the abnormal behaviour were identified in 11 animals; these included ear mite infestation, otitis interna, cranial nerve dysfunction, cervical injury, ocular disease, guttural pouch mycosis, dental periapical osteitis and suspected vasomotor rhinitis. However, in only two of these could it be shown that correction of the abnormality led to elimination of the headshaking. The additional clinical signs exhibited by the other idiopathic cases of headshaking included evidence of nasal irritation, sneezing ...
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.
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.
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.
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...
Pickles K.Horses with trigeminal mediated headshaking (TMHS) have a decreased activation threshold of the trigeminal nerve and clinical signs are suspected to be a manifestation of trigeminal neuralgia. Electrical nerve stimulation (ENS) is used for management of neuralgia in humans and appears to work via gate control theory. Use of an equine specific percutaneous ENS program in over 130 TMHS horses has resulted in approximately 50% success return to previous work. Electroacupuncture may also be useful in the management TMHS. Optimization of ENS procedures for TMHS is likely to require a greater unders...
Stange LM, Krieter J, Czycholl I.Equine headshaking syndrome is a problematic behavior that has been described in literature for more than 100 years. The signs of headshaking syndrome appear frequently and violently so that riding the horse can be dangerous. The aim of this research was to gain an overview of the underlying causes of equine headshaking syndrome to identify effective treatment options, reduce the distress of horses and, in a second step, potentially improve therapeutic possibilities for horse owners and veterinarians. Most studies on prevalence originate from Anglo-American countries, so this research was to ...
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...
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...
Ross SE, Murray JK, Roberts VLH.Headshaking in horses has been reported to be most commonly due to idiopathic neuropathic facial pain (trigeminal-mediated headshaking). The prevalence of headshaking in horses in the UK is unknown. Objective: To estimate owner-reported prevalence of headshaking in horses in the UK and to report their case background and disease characteristics, as reported by owners. Methods: Cross-sectional web based owner questionnaire. Methods: The questionnaire was advertised online via social media, horse forums, veterinary websites and equestrian magazines from 17th June 2016, until >1000 responses had ...
Kloock T, Pickles KJ, Roberts V, Uhlendorf F, Twele L, Wilkens HL, Stehle E, Feige K, Niebuhr T.In horses with trigeminal-mediated headshaking (TMHS), clinical signs are likely to be expression of neuropathic facial pain. Currently, subjective assessment of disease severity is used as measure of compromise of animal's welfare. Objective: To develop and validate a precise scoring system for TMHS: History, Rest and Exercise Score (HRE-S). The HRE-S consists of three subscores: history score (H-S), resting score (R-S) and exercise score (E-S). Methods: Retrospective observational study. Methods: Seven masked observers with different experience used HRE-S to score 40 video recordings taken d...
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...
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...
Stange LM, Krieter J, Czycholl I.Equine headshaking syndrome (EHS) is characterised as non-physical and involuntary movement of the horse's head and neck. Although EHS is clinically simple to diagnose, its aetiopathogenesis often remains unclear. The aim of this study was to gain an overview of signalment and therapy possibilities used in France and Switzerland. To do this, an online survey was developed and distributed via newsletters. A total of 933 complete, answered surveys from France ( = 804) and Switzerland ( = 129) were evaluated. The median age in France was 12.4 years (CH = 14.3). Mostly geldings were affected (58.5...
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...
Sheldon SA, Aleman M, Costa LRR, Santoyo AC, Howey Q, Madigan JE.Trigeminal-mediated headshaking results from low-threshold firing of the trigeminal nerve resulting in apparent facial pain. Magnesium may have neuroprotective effects on nerve firing that potentially dampen signs of neuropathic pain. This hypothesis has not been investigated in horses with trigeminal-mediated headshaking. Objective: To investigate head-shaking behavior in affected horses after IV magnesium sulfate infusion. Methods: Six geldings with trigeminal-mediated headshaking. Methods: Prospective randomized crossover study. Horses were controlled for diet and infused IV with 5% dextros...
Sheldon S, Aleman M, Costa L, Santoyo AC, Howey Q, Madigan J.Trigeminal-nerve-mediated headshaking represents a major welfare challenge for owners and veterinarians and is caused by a low threshold firing of the trigeminal nerve resulting in pain manifested as violent head jerking that often terminates the horse’s career and life due to poor quality of life and suffering. As metabolic changes such as acid⁻base status and electrolytes play a role in nerve firing, this study sought to assess the effects following administration of hypertonic solutions on headshaking behavior in affected horses. This prospective randomized controlled crossover desi...
Lane JG, Mair TS.The clinical records of 100 cases of headshaking in horses were reviewed. Possible causes of the abnormal behaviour were identified in 11 animals; these included ear mite infestation, otitis interna, cranial nerve dysfunction, cervical injury, ocular disease, guttural pouch mycosis, dental periapical osteitis and suspected vasomotor rhinitis. However, in only two of these could it be shown that correction of the abnormality led to elimination of the headshaking. The additional clinical signs exhibited by the other idiopathic cases of headshaking included evidence of nasal irritation, sneezing ...
Fenner MF, Verwilghen D, Townsend N, Simhofer H, Schwarzer J, Zani DD, Bienert-Zeit A.Paranasal sinus cysts (PSC) are a common cause of equine secondary sinusitis. The outcome and associated complications have not been frequently reported. Objective: To review the associated clinical signs, associated morbidities and outcomes of horses treated for PSC. Methods: Retrospective multicentre case series. Methods: Retrospective analysis of case records and telephone follow up survey. Results: Subjects were 37 horses 1-24 years old that were presented with nasal discharge (n = 31), facial swelling (n = 25) and epiphora (n = 19). Radiography and computed tomography allowed identificati...
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...
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 ...
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...
