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.
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.
Franzen V, Gruber NA, Klußmann S, Schoster A, May A.Trigeminal-mediated headshaking is a neuropathic facial pain condition in horses. No treatment has been entirely successful. Repetitive transcranial magnetic stimulation (rTMS) is used in human medicine as a treatment for various neuropathic pain conditions, and good results have been achieved in cases of trigeminal neuralgia. Objective: Apply rTMS to horses with trigeminal-mediated headshaking (TMHS) and to evaluate tolerability, application of the setting, and success rate. Methods: Seventeen horses with nonseasonal signs of TMHS. Methods: Other underlying causes of headshaking were ruled ou...
Witt P, Stas EKL, Hardeman LC, van Proosdij ER, Weerts EAWS, Lloyd-Edwards RA, Veraa S, Kranenburg LC, van den Boom R.A sixteen-year-old Friesian mare was admitted to the university clinic with the following clinical signs: anorexia, weight loss, fever, bilateral nasal discharge, unilateral facial paralysis and a non-healing corneal lesion. Endoscopic examination of the upper airways showed thickening of the proximal portion of the right stylohyoid bone. Computed tomography imaging showed pneumocephalus due to grade 3 unilateral temporohyoid osteoarthropathy (THO) with fracture of the petrous temporal bone. The horse did not improve following medical treatment. Surgical intervention was declined by the owner ...
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...
Forni G, Ellero N, Mannini A, Scacco L, Freccero F.A 3-year-old Quarter Horse stallion was referred for headshaking (HS) syndrome of one month duration. The horse underwent complete HS workup. Physical examination revealed up-and-down head movements associated with nose snorting during lunging and riding, in the absence of other abnormalities at rest or in motion. Lameness, neurologic and behavioural evaluations were unremarkable. Endoscopic examination of the upper respiratory tract showed bilateral guttural pouches (GPs) inflammation. The mucosal surface was altered by the presence of areas of microbullous appearance coalescing into some bul...
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...
Heun F, Delarocque J, Feige K, Hellige M.Nerve atrophy results in trigeminal nerve (TN) asymmetry detectable by magnetic resonance imaging (MRI) in humans, but similar studies have not been performed in horses with idiopathic trigeminal-mediated headshaking (ITMHS). Objective: Horses with ITMHS show greater MRI-detected trigeminal-nerve asymmetry than controls. Methods: A total of 20 adult horses with ITMHS and six unaffected control horses. Methods: Retrospective case-control study of the TN cross-sectional area (TNCSA) based on 3-Tesla MRI scans of the equine brain. TNCSA and its side-to-side differences at four defined measurement...
Aleman M, Morales CJ.Idiopathic trigeminal-mediated headshaking is a painful neuropathic disorder characterized by sudden, violent, predominantly vertical head movements of unknown etiology. Clinical signs may be seasonal or persistent and triggered by light, sound, exercise, or tactile nasal stimulation. The pathophysiology is multifactorial, involving abnormal trigeminal nerve excitability influenced by hormonal, environmental, and dietary factors. Treatment is challenging and typically multimodal, aiming to reduce trigeminal hypersensitivity and improve quality of life.
