The equine spine is a complex structure composed of numerous vertebrae that provide support, facilitate movement, and protect the spinal cord. It is divided into several regions: cervical, thoracic, lumbar, sacral, and coccygeal, each contributing to the overall biomechanics and flexibility of the horse. The spine plays a significant role in the horse's locomotion, posture, and ability to perform various tasks. Research on the equine spine encompasses studies on its anatomy, function, and the impact of various conditions such as injuries, deformities, and age-related changes. This page compiles peer-reviewed research studies and scholarly articles that explore the structural and functional aspects of the equine spine, as well as its role in equine health and performance.
Lesimple C, Fureix C, De Margerie E, Sénèque E, Menguy H, Hausberger M.Postures have long been used and proved useful to describe animals' behaviours and emotional states, but remains difficult to assess objectively in field conditions. A recent study performed on horses using geometric morphometrics revealed important postural differences between 2 horse populations differing in management conditions (leisure horses living in social groups used for occasional "relaxed" riding/riding school horses living in individual boxes used in daily riding lessons with more constraining techniques). It was suggested that these postural differences may reflect chronic effects...
Molnar R, Barber SM, Pharr JW, Panizzi L, Plaxton A.A Quarter horse gelding sustained fracture and displacement of spinous processes T2-T10. Radiographic evidence of healing was seen 3 mo following injury, and at 2 years post-injury all spinous processes had healed and undergone partial re-alignment. This re-alignment has not been reported before. Un hongre Quarter horse a subi une fracture et un déplacement des apophyses épineuses T2–T10. Les preuves radiographiques de la guérison ont été observées 3 mois après la blessure et 2 ans après la blessure toutes les apophyses épineuses avaient guéri et subi un réalignement partiel. Ce ...
Andersson LS, Larhammar M, Memic F, Wootz H, Schwochow D, Rubin CJ, Patra K, Arnason T, Wellbring L, Hjälm G, Imsland F, Petersen JL, McCue ME....Locomotion in mammals relies on a central pattern-generating circuitry of spinal interneurons established during development that coordinates limb movement. These networks produce left-right alternation of limbs as well as coordinated activation of flexor and extensor muscles. Here we show that a premature stop codon in the DMRT3 gene has a major effect on the pattern of locomotion in horses. The mutation is permissive for the ability to perform alternate gaits and has a favourable effect on harness racing performance. Examination of wild-type and Dmrt3-null mice demonstrates that Dmrt3 is exp...
Cudmore LA, Groenendyk JC, Hodge P, Church S.This case report describes neurological signs associated with a pyogranulomatous lesion within the sacral vertebral canal of a horse. The clinical findings included urinary overflow incontinence and reduced anal, perianal and tail tone. The horse failed to respond to medical management and a guarded prognosis for return to athletic performance initiated the decision for euthanasia.
Clayton HM, Kaiser LJ, Lavagnino M, Stubbs NC.To identify differences in intersegmental bending angles in the cervical, thoracic, and lumbar portions of the vertebral column between the end positions during performance of 3 dynamic mobilization exercises in cervical lateral bending in horses. Methods: 8 nonlame horses. Methods: Skin-fixed markers on the head, cervical transverse processes (C1-C6) and spinous processes (T6, T8, T10, T16, L2, L6, S2, and S4) were tracked with a motion analysis system with the horses standing in a neutral position and in 3 lateral bending positions to the left and right sides during chin-to-girth, chin-to-hi...
Clayton HM, Belock B, Lavagnino M, Kaiser LJ.The objectives of this study were to measure forces and pressure profiles when riding with a conventional saddle compared to bareback riding. An electronic pressure mat was used to compare contact area, mean total force and pressure variables for one rider riding seven horses at sitting trot with a conventional saddle or bareback. The use of a saddle was associated with a larger contact area and higher mean total force compared with the bareback condition. Mass normalized mean total force for bareback riding was lower than expected based on the rider's body mass, suggesting that shear forces e...
Coomer RP, McKane SA, Smith N, Vandeweerd JM.To compare the results of a novel minimally invasive surgical technique with intralesional corticosteroid medication, as treatment for overriding dorsal spinous processes (ORDSP) in horses. Methods: Retrospective controlled clinical case series. Methods: Horses (n = 68) with ORDSP. Methods: ORDSP was diagnosed based on history, clinical, and radiographic examination. All narrowed spaces were treated. Horses undergoing medical treatment had methylprednisolone acetate injected directly in the affected space under radiographic control. Surgical cases had interspinous ligament desmotomy (ISLD) usi...
Lima EF, Riet-Correa F, Gardner DR, Barros SS, Medeiros RM, Soares MP, Riet-Correa G.Poisoning by Indigofera lespedezioides is reported in horses in the state of Roraima, northern Brazil. The main clinical signs are anorexia, sleepiness, unsteady gait, severe ataxia, weakness, stumbling, and progressive weight loss. To induce the disease experimentally, a 7-year-old horse was introduced in a small paddock invaded by the plant. The first nervous signs were observed 44 days from the start of grazing. The animal was euthanized on day 59. No significant gross lesions were observed upon necropsies of the experimental horse as well as one spontaneously affected horse. Upon histologi...
Mitchell CW, Nykamp SG, Foster R, Cruz R, Montieth G.To determine the accuracy of magnetic resonance imaging for diagnosing cervical stenotic myelopathy in horses, 39 horses with spinal ataxia and 20 control horses underwent clinical and neurologic examinations, cervical radiographs, euthanasia, magnetic resonance (MR) imaging of the cervical spine and necropsy. Twenty-four horses were diagnosed with cervical stenotic myelopathy, 5 with cervical vertebral stenosis, 7 with idiopathic ataxia, 3 horses had other causes of ataxia, and 20 were controls. The MR images were assessed for spinal cord intensity changes, presence of spinal cord compression...
Wong DM, Ghosh A, Fales-Williams AJ, Haynes JS, Kanthasamy AG.The cervical spinal cords of 2 horses with equine degenerative myeloencephalopathy (EDM) were evaluated for evidence of oxidative damage to the central nervous system (CNS) using immunohistochemical staining for 3-nitrotyrosine (3-NT) and 4-hydroxynonenol (4-HNE). Neurons of the CNS from horses with EDM had positive immunohistochemical staining, whereas control samples did not, thus supporting the theory that oxidative damage is a potential underlying factor in horses with EDM. In addition, serum vitamin E concentration was low in both EDM-affected horses, and vitamin E concentration was also ...
Gordon AN, Marbach CR, Oakey J, Edmunds G, Condon K, Diviney SM, Williams DT, Bingham J.A 5-year-old Australian stock horse in Monto, Queensland, Australia, developed neurological signs and was euthanized after a 6-day course of illness. Histological examination of the brain and spinal cord revealed moderate to severe subacute, nonsuppurative encephalomyelitis. Sections of spinal cord stained positively in immunohistochemistry with a flavivirus-specific monoclonal antibody. Reverse transcription polymerase chain reaction assay targeting the envelope gene of flavivirus yielded positive results from brain, spinal cord, cerebrospinal fluid, and facial nerve. A flavivirus was isolate...
Tokunaga S, Fujiki M, Yabuki A, Misumi K.Cartilage-derived retinoic acid-sensitive protein (CD-RAP)/melanoma inhibitory activity (MIA), which appears abundantly in hypertrophic cartilage at the stage of endochondral ossification, is also detected in cerebrospinal fluid (CSF) following spinal cord injury. In this study, the localization of the CD-RAP/MIA molecule in normal tissues of the spine and brain obtained from mice, rats, dogs, cattle and horses was examined using immunohistochemistry with a specific antibody. The positive signals of CD-RAP/MIA were found at nerve cells in the spinal cords of all species and were especially str...
Russo D, Castellani G, Chiocchetti R.Spinal ganglion (SG) neurons are subdivided, on the basis of their cytoplasmic aspect at light and electron microscopy, into dark (D) and light (L) neurons. Numerous efforts have been made to find specific markers able to identify D and L neuronal cytotypes. The isolectin B4 (IB4), utilized to identify nonpeptidergic D neurons in mice, unfortunately, has not proved as effective in other species. The 200-kDa neurofilament protein (NF200) is considered as a typical marker of L neurons in the rat, cat, and chick. The aim of this study was to analyze the histological, morphometric, and neurochemic...
Schmidburg I, Pagger H, Zsoldos RR, Mehnen J, Peham C, Licka TF.Laterolateral radiographs of equine necks are reported to be inaccurate in determining the site of spinal cord lesions even when a myelogram is carried out. The goal of this study was to assess constrictions present in the cervical vertebral canal at any time point throughout the extremes of movement. Sixteen equine cervical vertebral columns without history of cervical disease were used. After removal of the spinal cord, the dura mater was filled with polyurethane foam and during its plastic phase the cervical vertebral column was passively moved in flexion-extension, lateral bending and 30°...
Ohba T, Ebata S, Ando T, Ichikawa J, Clinton D, Haro H.Hematoma of the ligamentum flavum is a rare cause of neural compression, for which treatment has consisted of excising the hematoma via open surgical approaches, including total laminectomy or bilateral partial laminectomy. This article presents the first report of a microscope-assisted endoscopic decompression to resect a hematoma of the ligamentum flavum.A 52-year-old man presented with back and leg pain, as well as difficulty initiating micturation. Magnetic resonance imaging demonstrated an epidural mass at L5/S1 that was continuous with the facet joint. Visualization was obtained via an e...
Zimmerman M, Dyson S, Murray R.Back pain is common in horses, but there has been no large-scale in-depth study describing radiographic changes of the spinous processes, the relationship between radiographic and scintigraphic findings, and the effect of size, age, breed, or discipline. The objectives were to investigate the frequency of occurrence in horses with perceived back pain of: (1) radiographic alteration of the spinous process structure; (2) increased radiopharmaceutical uptake (IRU) in the spinous processes; and (3) to compare radiographic and scintigraphic findings; and to determine if there was breed, gender, age...
Prange T, Carr EA, Stick JA, Garcia-Pereira FL, Patterson JS, Derksen FJ.A 3-year-old Thoroughbred gelding presented with a history of neurological signs, including incoordination in his hindlimbs, of about 7 months' duration. On initial examination, the horse exhibited ataxia and paresis in all limbs with more severe deficits in the hindlimbs. Cervical radiographs displayed severe osteoarthritis of the articular processes between C5 and C6. On subsequent cervical myelography the dorsal contrast column was reduced by 90% at the level of the intervertebral space between C5 and C6. Cervical vertebral canal endoscopy, including epidural (epiduroscopy) and subarachnoid...
Stubbs NC, Riggs CM, Hodges PW, Jeffcott LB, Hodgson DR, Clayton HM, McGowan CM.The multifidus muscle plays a key role in spinal stabilisation. Multifidus atrophy ipsilateral to the side of osseous pathology has been demonstrated in man and pigs but has not been investigated in horses. Objective: To measure cross-sectional area (CSA) left/ right symmetry of equine multifidus ultrasonographically and relate asymmetry of multifidus with osseous spinal pathology in Thoroughbred racehorses. We hypothesised that ipsilateral multifidus CSA would be reduced when osseous pathological changes are present leading to left/right asymmetry in CSA. Methods: Twenty-two racehorses presen...
Sleutjens J, Voorhout G, Van Der Kolk JH, Wijnberg ID, Back W.In dressage, the head and neck position has become an issue of concern as certain extreme positions may imply a welfare risk for the horse. In man, extension and flexion of the cervical spine cause a decrease and increase in intervertebral foramina dimensions, respectively. However, in horses, the influence of flexion and extension on foramina dimensions and its possible interference with peripheral nerve functioning remains unknown. Objective: To determine the effect of ex vivo flexion and extension on intervertebral foramina dimensions in the equine cervical spine. Methods: Computed tomograp...
Zsoldos RR, Groesel M, Kotschwar A, Kotschwar AB, Licka T, Peham C.The motion of the atlanto-occipital, cervical vertebral and cervicothoracic joints play an important role in equestrian sports and they are also common sites for lesions limiting performance in horses. Objective: To calculate inverse kinematics based on cervical vertebral motion and to develop a model close to the measured neck movements. Methods: Measurements were recorded in 6 horses without neck pain. Reflective markers were placed on both cristae facialis, both sides of cervical vertebra 1, 3 and 6 on the withers and hooves. The neck model was reconstructed from CT scans of the osseus stru...
Haussler KK, Martin CE, Hill AE.Spinal mobilisation and spinal manipulative therapy (SMT) are being applied to horses; however, there are limited objective measures of their effects on spinal mobility or stiffness in actively ridden horses. Objective: To quantify passive spinal movements induced during dorsoventral mobilisation of the trunk and to identify any potential effects of SMT on measures of spinal mobility within the thoracolumbar region in standing horses. We hypothesise that displacement amplitudes will be significantly increased across vertebral levels after SMT, compared to spinal mobilisation only within the co...
Zsoldos RR, Kotschwar A, Kotschwar AB, Rodriguez CP, Peham C, Licka T.The rectus abdominis (RA) and oblique external abdominal (OEA) muscles are both part of the construction of the equine trunk and thought to be essential for the function of the spine during locomotion. Although RA activity at trot has previously been investigated, the relationship between OEA and RA at walk and trot has not yet been described. Objective: To document abdominal muscle activities during walk and trot, and test the hypothesis that muscle activity at walk would be smaller than at trot. Methods: Six horses (8-20 years old, 450-700 kg) were used for surface electromyography (EMG) mea...
Warner SM, Koch TO, Pfau T.Assessing back movement is an important part of clinical examination in the horse and objective assessment tools allow for evaluating success of treatment. Objective: Accuracy and consistency of inertial sensor measurements for quantification of back movement and movement symmetry during over ground locomotion were assessed; sensor measurements were compared to optical motion capture (mocap) and consistency of measurements focusing on movement symmetry was measured. Methods: Six nonlame horses were trotted in hand with synchronised mocap and inertial sensor data collection (landmarks: T6, T10,...
Latif SN, Von Peinen K, Wiestner T, Bitschnau C, Renk B, Weishaupt MA.To a large extent the success of a racehorse depends on effective and health preserving training methods. An important issue is the prevention of back pain. The influence of different types of training saddles (normal tree: S(A), treeless: S(B), flexible tree: S(C)) on the saddle pressure patterns in racehorses have not previously been investigated. It is commonly assumed that S(A) limits the motion of the back especially in the lower thoracic region during gallop. Objective: S(A) produces higher pressures in the caudal part of the saddle at trot (rising trot), canter and gallop (both in a joc...
von Peinen K, Wiestner T, von Rechenberg B, Weishaupt MA.Similar to human decubitus ulcers, local high pressure points from ill-fitting saddles induce perfusion disturbances of different degrees resulting in tissue hypoxia and alteration in sweat production. Objective: To relate the different clinical manifestations of saddle sores to the magnitude of saddle pressures at the location of the withers. Methods: Sixteen horses with dry spots after exercise (Group A) and 7 cases presented with acute clinical signs of saddle pressure in the withers area (Group B) were compared with a control group of 16 sound horses with well fitting saddles (Group C). Al...
Hessler C, Namislo V, Kammler G, Lockemann U, Püschel K, Meenen NM.Horseback riding entails several risk factors that predispose the participant to injury. Especially craniocerebral as well as spinal trauma were common reasons for severe injuries. Hence, it is important to use effective protective gear during riding activities. However, the protective effect of actual safety vests and helmets in case of accident is still unknown. In the present study reasons, mechanisms and patterns of equine-related spine injuries were analyzed. Based on these data the effectiveness of used protective gear during accident was assessed. Methods: 30 equestrians took part in a ...
Sponseller BA, Sponseller BT, Alcott CJ, Kline K, Hostetter J, Reinertson EL, Fales-Williams A.Syringomyelia and hydromyelia are cavitary lesions of the spinal cord that may be acquired or congenital. These lesions are not frequently reported in large animal species. The presenting complaints, clinical, gross pathological, and histopathologic findings of 2 cases of syringomyelia and 1 case of hydromyelia in horses are described. La syringomyélie et l’hydromyélie sont des lésions cavitaires de la colonne vertébrale qui peuvent être acquises ou congénitales. Ces lésions ne sont pas fréquemment signalées chez les espèces de grands animaux. Les plaintes de présentation et les ...
Hansmann F, Herder V, Ernst H, Baumgärtner W.This report is the first description of a spinal epidermoid cyst (EC) in a SJL mouse and gives an overview on the occurrence of ECs in animals including dogs, horses, mice and rats. The EC was not detected grossly and the mouse did not display clinical signs or an altered rotarod performance. Microscopically, there was an oval cyst lined by stratified squamous epithelium that was attached to the dorsolateral meninges and caused moderate compression of the adjacent lumbar spinal cord. ECs in mice and rats are mainly located in the caudal part of the spinal cord with a variable, strain-dependent...
Wijnberg ID, Graubner C, Auriemma E, van de Belt AJ, Gerber V.Reference values for quantitative electromyography (QEMG) in neck muscles of Royal Dutch Sport horses are lacking. Objective: Determine normative data on quantitative motor unit action potential (QMUP) analysis of serratus ventralis cervicis (SV) and brachiocephalicus (BC) muscle. Methods: Seven adult normal horses (mean age 9.5 standard deviation [SD] ± 2.3 years, mean height 1.64 SD ± 4.5 cm, and mean rectal temperature 37.6 SD ± 0.3°C). Methods: An observational study on QMUP analysis in 6 segments of each muscle was performed with commercial electromyography equipment. Measurements wer...
Haussler KK, Stover SM.Thirty-six Thoroughbred racehorses that died at California racetracks between October 1993 and July 1994 were evaluated for stress fractures in the caudal portion of the thoracic and lumbosacral regions of the spine and the pelvis. The lumbosacral spine and pelvis were collected, debrided of soft tissues and examined visually for the presence of an incomplete fracture line and focal periosteal proliferation, characteristic of a stress fracture. Sixty-one per cent of specimens had evidence of stress fracture in the caudal portion of the thoracic and lumbosacral regions of the spine and the pelv...
Meneses CS, Müller HY, Herzberg DE, Uberti B, Bustamante HA, Werner MP.The role of glial cells in pain modulation has recently gathered attention. The objective of this study was to determine healthy spinal microglia and astrocyte morphology and disposition in equine spinal cord dorsal horns using Iba-1 and GFAP/Cx-43 immunofluorescence labeling, respectively. Five adult horses without visible wounds or gait alterations were selected. Spinal cord segments were obtained post-mortem for immunohistochemical and immunocolocalization assays. Immunodetection of spinal cord dorsal horn astrocytes was done using a polyclonal goat antibody raised against Glial Fibrillary ...
Cassiat G, Pourcelot P, Tavernier L, Geiger D, Denoix JM, Degueurce D.The costs and investments required for the purchase and training of showjumpers justify the need to find selection means for jumping horses. Use of objective kinematic criteria correlated to jumping ability could be helpful for this assessment. Objective: To compare back kinematics between 2 groups of horses of different competition levels (Group 1, competing at high level; Group 2 competing at low level) while free jumping over a 1 m vertical fence. Methods: Three-dimensional recordings were performed using 2 panning cameras. Kinematic parameters of the withers and tuber sacrale (vertical dis...
Mittelman NS, Divers TJ, Engiles JB, Gerhold R, Ness S, Scrivani PV, Southard T, Johnson AL.There are reports of horses with acute onset acquired cervical scoliosis and cutaneous analgesia. The underlying dorsal gray column myelitis that produces these neurologic signs has been only presumptively attributed to migration of Parelaphostrongylus tenuis within the spinal cord. Despite previous confirmation brain by polymerase chain reaction testing, of P. tenuis within the brain of horses by polymerase chain reaction testing, genetic testing has failed to definitively identify the presence of this parasite in cases of equine myelitis. This case report provides molecular confirmation via ...
A 4-week old Quarter Horse filly was evaluated for abnormal gait and lateral deviation of the cervical spine. Physical examination findings prompted radiographs and computed tomography of the thoracic vertebral column which revealed hypoplasia of several thoracic vertebral bodies and resultant scoliosis of the thoracic vertebral column and deviation of the left and right hemithoraces and associated ribs. Collectively, radiography and computed tomography provided an accurate description of the vertebral malformations resulting in scoliosis in this foal.
Finno CJ, Johnson AL.Neuroaxonal degenerative disease in the horse is termed equine neuroaxonal dystrophy (eNAD), when pathologic lesions are localized to the brainstem and equine degenerative myeloencephalopathy (EDM) and degenerative changes extend throughout the spinal cord. Both pathologic conditions result in identical clinical disease, most commonly characterized by the insidious onset of ataxia during early development. However, later onset of clinical signs and additional clinical features, such as behavior changes, is also observed. A definitive diagnosis of eNAD/EDM requires histologic evaluation of the ...
Lorenzett MP, Pereira PR, Bassuino DM, Konradt G, Panziera W, Bianchi MV, Argenta FF, Hammerschmitt ME, Caprioli RA, de Barros CSL, Pavarini SP....Trema micrantha is a tree widely distributed throughout the Americas. The tree produces highly palatable leaves that have been associated with natural poisoning in goats, sheep and horses, in which hepatic necrosis and hepatic encephalopathy have been observed. Objective: This study describes malacia and haemorrhage in the central nervous system (CNS) due to T. micrantha consumption, with minimal to absent hepatic lesions. Methods: Retrospective case series. Methods: A total of 14 horses with a history of neurological signs and spontaneous consumption of T. micrantha leaves were submitted to...
Tomizawa N, Nishimura R, Sasaki N, Hayashi Y, Senba H, Hara S, Kadosawa T, Takeuchi A.Morphological differences between cervical vertebrae were statistically analyzed in ataxic foals to clarify abnormal structural factors in the pathogenesis of this problem. At first, multiple regression analysis and cluster analysis were performed with 28 variables in C3-C7 of 39 control foals without lameness. As a result, there were no sex differences in the growth of all cervical vertebral sites, and the most suitable categorization of the age of the foals was 3 clusters of 8 months old or younger, 9-12 months old and 13 months old or older in any sites in the cervical vertebrae. Twenty-eig...
Bianchi M, Merighi A.Histochemical and cytochemical features of neuronal pigment in the spinal cord, and in the sympathetic and spinal ganglia of the adult horse have been studied. Light and electron microscopical observations revealed that lipofuscin pigment is present in the spinal ganglia and in the spinal cord, whereas in the sympathetic ganglia both lipofuscin and neuromelanin are present. The ultrastructural studies showed that lipofuscin granules exhibited a triphasic organization consisting of a matrix, a system of lamellae and one or more lipid vacuoles. Neuromelanin granules have structural features in c...
Shakeshaft A, Tabor G.Dynamic mobilisation exercises (DME) are often used as part of a physiotherapy rehabilitation programme. Whilst immediate kinematic effects have been measured, the change in posture is anecdotally reported to have a longer duration. This study aimed to test the reliability of a simple objective measurement method, suitable for use in clinical practice, and to objectively measure equine thoracolumbar posture, before and after DME. A single investigator took triplicate measurements of the sagittal thoracolumbar shape using a flexicurve ruler (FCR) then triplicate measurements of the thoracolumba...
Swagemakers JH, Van Daele P, Mageed M.Cervical spinal nerve insult can be a sequel of osteoarthropathy in horses due to enlargement of the articular processes (AP). Objective: To describe the percutaneous endoscopic cervical foraminotomy procedure in horses. Methods: Ex vivo experimental study and clinical case report. Methods: The technique was performed in three equine cadavers and in two clinical cases with history of forelimb lameness located in the caudal cervical region. Briefly, the horse was positioned in lateral recumbency, with the affected AP joint uppermost. Under fluoroscopic guidance, the endoscopic instruments (Ø 6...
de Souza TC, Crowe OM, Bowles D, Poore LA, Suthers JM.To describe a minimally invasive cranial ostectomy for the treatment of impingement of dorsal spinous processes (DSPs) in the standing horse. Methods: Retrospective study. Methods: One hundred two horses with impinging DSPs. Methods: The case records of all horses that had the described technique between 2011 and 2019 were reviewed. All sites of impinging DSPs were treated under standing sedation and local anesthesia. The minimally invasive cranial ostectomy of the caudal DSP was performed with bone rongeurs through multiple small incisions. Results: Of the 102 horses treated with this techniq...
O'Leary SA, White JL, Hu JC, Athanasiou KA.The equine cervical facet joint is a site of significant pathology. Located bilaterally on the dorsal spine, these diarthrodial joints work in conjunction with the intervertebral disc to facilitate appropriate spinal motion. Despite the high prevalence of pathology in this joint, the facet joint is understudied and thus lacking in viable treatment options. Objective: The goal of this study was to characterise equine facet joint cartilage and provide a comprehensive database describing the morphological, histological, biochemical and biomechanical properties of this tissue. Methods: Descriptive...
Boham M, O'Connell K.To introduce the characteristics of a Chance fracture and increase awareness of the mechanism of injury that may occur during athletic activity. Background: A T12 Chance fracture was diagnosed in an 18-year-old male rodeo athlete. The rider was forced into extreme lumbothoracic hyperflexion when the horse bucked within the chute, pinning the rider's legs to his chest. Methods: Burst fracture, abdominal organ rupture, spinal dislocation, spinal cord injury, disk herniation, pars interarticularis fracture, spinal nerve injury, paralysis. Methods: The patient underwent an open reduction and fixat...
Beech J.The cytology of cerebrospinal fluid samples from horses is described. The samples were obtained from 24 normal horses, 35 horses with axonal degeneration and/or spinal cord compression, 29 horses with encephalomyelitis, 14 horses with other lesions of the nervous system, and eight horses with signs of neurologic dysfunction of undetermined origin. (Three of the latter were suspected botulinum intoxications.) Fluid was aspirated from the atlanto-occipital space following general anesthesia or immediately after a lethal dose of barbiturate. In two horses, fluid also was aspirated from the lumbos...
Szklarz M, Lipinska A, Slowikowska M, Niedzwiedz A, Marycz K, Janeczek M.Cervical vertebral stenotic myelopathy (CVSM) remains one of the most important abnormalities of the cervical spine resulting in neurological deficits in horses. The aim of the following study was to compare the results of the clinical and neurological examination, the results of myelography and the post mortem anatomical and histological appearance of the spinal cord and cervical vertebrae in a horse with CVSM. Methods: The following study describes a clinical case of an eight-month-old stallion with ataxia. Plain cervical radiographs indicated narrowing of the spinal canal. Conservative ther...
Derham AM, Schumacher J, O' Leary JM, Kelly G, Hahn CN.Impinging/overriding dorsal spinous processes (DSPs) of the thoracolumbar vertebrae are a common cause of poor performance in horses. In the last five decades, numerous surgical treatments have been reported on, from transverse transection of the affected DSPs, and endoscopic resection of the affected DSPs, to transection of the interspinous ligament. Until recently, cosmetic outcomes have been reported as good to excellent in studies. However, a previously unreported complication of neurogenic atrophy of the contralateral epaxial muscle following desmotomy of the interspinous ligament has bee...
Aleman M, Dimock AN, Wisner ER, Prutton JW, Madigan JE.A 2-year-old Thoroughbred gelding with clinical signs localized to the first 6 spinal cord segments (C1 to C6) had complete fusion of the atlanto-occipital bones which precluded performing a routine myelogram. An ultrasound-assisted myelogram at the intervertebral space between the atlas and axis was successfully done and identified a marked extradural compressive myelopathy at the level of the atlas and axis, and axis and third cervical vertebrae. Un hongre Thoroughbred âgé de 2 ans avec des signes cliniques localisés aux 6 premiers segments de la colonne vertébrale (C1 à C6) avait une ...
Schmidburg I, Pagger H, Zsoldos RR, Mehnen J, Peham C, Licka TF.Laterolateral radiographs of equine necks are reported to be inaccurate in determining the site of spinal cord lesions even when a myelogram is carried out. The goal of this study was to assess constrictions present in the cervical vertebral canal at any time point throughout the extremes of movement. Sixteen equine cervical vertebral columns without history of cervical disease were used. After removal of the spinal cord, the dura mater was filled with polyurethane foam and during its plastic phase the cervical vertebral column was passively moved in flexion-extension, lateral bending and 30°...
Aldrich E, Nout-Lomas Y, Seim HB, Easley JT.To evaluate safety and efficacy of a novel technique for cervical stabilization. Methods: In vivo experimental. Methods: Four normal adult quarterhorse crossbreed horses (2-4 years of age, > 250 kg). Methods: One mid-cervical spinal unit (C3-C4) was distracted with a porous metal interbody fusion device (IFD) and stabilized with a polyaxial pedicle screw and rod construct. Neurologic examinations were performed preoperatively and postoperatively. Radiographs of the fusion site and adjoining vertebrae were obtained preoperatively and monthly. Horses were euthanized at 8 months and spin...
Yovich JV, leCouteur RA, Gould DH.Histological examination was performed on the cervical spinal cord from 13 horses with chronic cervical compressive myelopathy of 4 to 29 months duration. Structural alterations were correlated with clinical features. At the level of compression, the spinal cord was grossly deformed. Histological alterations included nerve fibre swelling and degeneration, occasional spheroids, astrocytic gliosis, increased macrophage activity and increased perivascular collagen. Myelin degeneration or loss at the level of the compressive lesion was greatest in the ventral and lateral funiculi and less consiste...
Jaafar N, Khoueiry M, Khoury SJ, Makki A.Spinal neurosarcoidosis is a rare disease that can manifest as myelopathy, radiculopathy, or cauda equine syndrome. Spinal epidural lipomatosis is also a rare condition resulting from overgrowth of epidural fat tissue causing compressive myelopathy. To our knowledge, there are no reports linking epidural lipomatosis and spinal neurosarcoidosis. . We describe a case of progressive myelitis in the presence of concomitant spinal neurosarcoidosis and epidural lipomatosis which was a challenging diagnosis with complete response to treatment after addressing both diseases. Both etiologies are inflam...
Slone DE, Bergfeld WA, Walker TL.A filly with ataxia and splinting and crepitation in the neck was found to have atlantoaxial subluxation. Radiographic diagnosis was based on the same criteria as those used in other species, ie, increased distance between the atlas and spine of the axis and increased distance between the dens and floor of the atlas. Extensive hemilaminectomy was performed to decompress the spinal cord. Stabilization was not attempted. Immediate postoperative response was encouraging, but the untimely death of the filly prevented further evaluation of the procedure.
Faber MJ, van Weeren PR, Schepers M, Barneveld A.In order to objectively quantify the effect of manipulation on back-related locomotion anomalies in the horse, a recently developed kinematic measuring technique for the objective quantification of thoracolumbar motion in the horse was applied in a dressage horse that was suffering from a back problem. In this horse, clinically, a right-convex bending (scoliosis) from the 10th thoracic vertebra to the second lumbar vertebra was diagnosed. As a result, there was a marked asymmetric movement of the thoracolumbar spine. Functionally, there was severe loss of performance. Thoracolumbar motion was ...
Stewart RH, Reed SM, Weisbrode SE.We compared the frequency and severity of osteochondrosis lesions in young Thoroughbred horses with cervical stenotic myelopathy (CSM) vs that in clinically normal Thoroughbreds of the same age. All lesions of the cervical vertebrae and appendicular skeleton were classified histologically as osteochondrosis or nonosteochondrosis and were measured for severity. Minimal sagittal diameter was significantly smaller in horses with CSM from C2 through C6; no difference was detected at C7. Severity of cervical vertebral osteochondrosis was greater in the horses with CSM, however frequency was not dif...
Journée SL, Journée HL, de Bruijn CM, Delesalle CJG.There are indications that transcranial electrical stimulation (TES) assesses the motor function of the spinal cord in horses in a more sensitive and reproducible fashion than transcranial magnetic stimulation (TMS). However, no normative data of TES evoked motor potentials (MEP) is available. Results: In this prospective study normative data of TES induced MEP wave characteristics (motor latency times (MLT); amplitude and waveform) was obtained from the extensor carpi radialis (ECR) and tibial cranialis (TC) muscles in a group of healthy horses to create a reference frame for functional diagn...
Pan LG, Forster HV, Wurster RD, Murphy CL, Brice AG, Lowry TF.We addressed the role of spinal afferent information in the exercise hyperpnea. Arterial PCO2 (PaCO2) was assessed in 10 normal ponies during low (1.8 mph 7% or 17% grade) or moderate (6 mph 7% grade) treadmill exercise. After control studies, bilateral spinal ablation (SA) of the dorsolateral sulcus and dorsolateral funiculus at L2 was performed in seven ponies. In normal ponies within the first 90 s of exercise, PaCO2 initially decreased 2.7, 4.1, and 5.2 Torr below rest at the three work loads, respectively (P less than 0.05). PaCO2 thereafter increased toward resting levels but remained 1....
Rickert M, Rauschmann M, Fleege C, Behrbalk E, Harms J.The development of interbody fusion now stretches over many decades and is still not complete. Conclusions: Due to the lack of appropriate implants, the initial fusions were performed via decortication of the dorsal and lateral structures of the spine, followed by placement of an autograft. Despite acceptable fusion results, better primary stability and higher fusion rates were desired. In addition, it became known that the primary load-bearing of the spine is located ventrally in the area of the corpus of the vertebrae. These considerations led to the development of the PLIF technique that wa...
Foldager C, Bendtsen M, Nygaard JV, Zou X, Bünger C.To investigate the microstructural differences and responsible mechanisms in early bone formation in anterior lumbar interbody fusion (ALIF) in the spine using rhBMP-2 (INFUSE), equine bone protein extract (COLLOSS E) or autograft. Methods: Twelve Danish female landrace pigs underwent a 3-level ALIF procedure at L3-6. PEEK interbody cages packed with rhBMP-2, COLLOSS E, or autograft were inserted. The animals were divided into two groups of six, and observed for four and eight weeks postoperatively. MicroCT was performed for evaluation of microstructure of the bone within the cage. A mathemati...
Clayton HM, Townsend HG.At least three types of movement, dorsoventral flexion and extension, axial rotation and lateral bending, were shown to occur at each of the intervertebral joints in the cervical spine. Between the first two cervical vertebrae the mean axial rotation was 107.5 degrees, which was 73 per cent of the total axial rotation of the cervical spine. The atlantooccipital joint rotated through a mean of 27 degrees, whereas the remaining cervical joints each had less than 3 degrees of rotatory movement. Dorsoventral flexion and extension were maximal at the atlantooccipital joint, which had an amplitude o...
