Radiology for horses involves the use of imaging techniques to diagnose and monitor various conditions affecting equine health. These techniques include X-rays, ultrasound, computed tomography (CT), and magnetic resonance imaging (MRI). Each modality provides different types of information, aiding in the evaluation of musculoskeletal disorders, respiratory issues, and abdominal problems, among others. Radiographic imaging is instrumental in identifying fractures, joint abnormalities, and dental issues. Ultrasound is often used for soft tissue evaluation and reproductive assessments. CT and MRI offer detailed cross-sectional images, enhancing the understanding of complex anatomical structures and pathologies. This page aggregates peer-reviewed research studies and scholarly articles that explore the applications, advancements, and findings in the field of equine radiology.
Anderson JD, Galuppo LD, Barr BC, Puchalski SM, Macdonald MM, Whitcomb MB, Magdesian KG, Stover SM.To describe clinical and scintigraphic abnormalities in horses with a bone fragility disorder. Methods: Retrospective case series. Methods: 16 horses with scintigraphic evidence of multiple sites of increased radiopharmaceutical uptake (IRU). Procedures-Medical records were reviewed for information on signalment; history; clinical, clinicopathologic, and diagnostic imaging findings; and treatment. Follow-up information was obtained through telephone interviews with owners. Results: Horses ranged from 4 to 22 years old; there were 8 castrated males and 8 females. Foci of IRU most commonly invol...
Ramzan PH, Marr CM, Meehan J, Thompson A.A novel radiographic projection is described for assessing part of the temporomandibular articulation of horses. It minimises the superimposition of osseous structures of the cranium that limit the usefulness of conventional projections and permits improved imaging in cases of suspected disease.
Kawcak CE, Frisbie DD, Werpy NM, Park RD, McIlwraith CW.To identify changes in imaging outcomes in a controlled model of osteoarthritis (OA) vs exercise. Methods: Sixteen 2-year-old horses were randomly assigned to an exercise control (n=8) or an exercise OA (n=8) group. All horses had middle carpal joints arthroscopically explored and an osteochondral fragment was induced in one middle carpal joint of the OA group. All horses were treadmill exercised for the duration of the study (91 days). Clinical, radiographic, nuclear scintigraphic, computed tomographic and magnetic resonance imaging (MRI) examinations were performed and outcomes of these were...
Cheetham J, Pigott JH, Thorson LM, Mohammed HO, Ducharme NG.The laryngeal tie-forward procedure (LTFP) is becoming widely used for correction of dorsal displacement of the soft palate (DDSP) despite the absence of an evidence-based assessment of its efficacy. Objective: The LTFP returns racing performance to preoperative baseline levels and to that of matched controls; and post operative laryngohyoid position is associated with post operative performance. Methods: Case-controlled study of racehorses undergoing a LTFP for dorsal displacement of the soft palate at Cornell University between October 2002 and June 2007. Methods: The presence of at least on...
Olstad K, Ytrehus B, Ekman S, Carlson CS, Dolvik NI.The developmental pattern of the cartilage canal blood supply to epiphyseal growth cartilage has been linked to osteochondrosis (OC) in the tarsus of foals. This pattern has not yet been described in the distal femur, another site frequently affected by OC. Objective: To describe the developmental pattern of the blood supply to the distal femoral epiphyseal growth cartilage in 8 Standardbred foals age 0-7 weeks. Methods: One foal was sacrificed weekly from birth to age 7 weeks (n=8) to undergo a barium perfusion procedure to demonstrate vessels within cartilage canals of one hindlimb. The dist...
van den Top JG, de Heer N, Klein WR, Ensink JM.Preputial and penile tumours are more common in horses than in other domestic animals, but no large surveys of male horses with tumours of the external genitalia are available. Objective: To present a retrospective analysis of male horses with neoplasms of the external genitalia. Methods: The penile and preputial tumours of 114 horses were evaluated. Data recorded included age, gelding or stallion and breed; type and site of lesion; involvement of regional lymph nodes; histopathology (including grading of squamous cell carcinoma); and results of radiographic examination of the thorax. Results:...
Dyson S, Blunden T, Murray R.Magnetic resonance imaging (MRI) is used with increasing frequency to diagnose injuries of the collateral ligaments (CLs) of the distal interphalangeal (DIP) joint, but the results have not been verified by histology and the mechanism of injury is poorly understood. Objective: Abnormal signal intensity and tissue contour represents change in tissue structure detected on histology. Objective: To compare results in horses free from and those with chronic lameness and to describe possible progression of lesions. Methods: One or both feet of horses free from lameness (Group N: n = 12) and with foo...
Olstad K, Cnudde V, Masschaele B, Thomassen R, Dolvik NI.Osteochondrosis (OC) is an important developmental orthopedic disease of human and equine patients. The disease is defined as a focal disturbance in enchondral ossification. In horses, the disturbance can occur secondary to failure of the blood supply to growth cartilage. Diagnosis of the early, subclinical stages that can clarify the etiology is currently confined to cross-sectional histological examination. The potential for micro-computed tomography (micro-CT) with angiography to detect early lesions of OC has not yet been investigated. Methods: Nine Standardbred foals bred from parents wit...
Vanderperren K, Saunders JH.The metacarpophangeal/metatarsophalangeal (fetlock) joint in the horse is commonly associated with equine lameness and diagnostic imaging is routinely used to investigate disorders of the joint and its surrounding tissues. This review describes the osseous disorders of the fetlock as well as the technical aspects of taking radiographic and ultrasonographic images of the different lesions. In current clinical practice, a combination of radiography and ultrasonography is still the most frequently used approach to arrive at a diagnosis.
Vanderperren K, Ghaye B, Snaps FR, Saunders JH.To determine the detailed computed tomography (CT) anatomy of the metacarpophalangeal (MCP) joint in healthy horses. Methods: 10 cadaveric forelimbs from 10 adult horses without orthopedic disease. Methods: CT of the MCP joint was performed on 4 forelimbs. In 1 of the limbs, CT was also performed after intra-articular injection of 30 mL of contrast medium (40 mg of iodine/mL). Transverse slices 1-mm thick were obtained, and sagittal and dorsal planes were reformatted with a slice thickness of 2 mm. The CT images were matched with corresponding anatomic slices from 6 additional forelimbs. Resul...
Vlaminck L, Cnudde V, Pieters K, Van Den Broeck W, Steenhaut M, Jacobs P, Gasthuys F.To evaluate the biological behavior of a nonresorbable bone substitute (NRBS) in the alveoli of ponies, compared with tissue quality in naturally healing alveoli, after cheek tooth extraction. Methods: 5 clinically normal ponies. Methods: In each pony, both maxillary fourth premolars (Triadan 108/208) were repulsed bilaterally during anesthesia. One randomly chosen alveolus was filled with NRBS and isolated from the oral cavity by use of dental impression material and a spring-wire retention device. The other alveolus was occluded in its occlusal third portion with dental impression material. ...
Bell SA, Drew CP, Wilson WD, Pusterla N.Idiopathic chronic eosinophilic pneumonia of horses is incompletely described. Objective: To describe the physical examination, clinicopathologic, histopathologic, and radiographic features and response to corticosteroid treatment of idiopathic chronic eosinophilic pneumonia of horses. Methods: Seven horses with eosinophilic pneumonia. Methods: Retrospective, descriptive study. Results: Anamnesis, clinical signs, and clinicopathologic and radiologic findings in 7 adult horses with histologically confirmed eosinophilic pneumonia were reviewed. The horses were examined for signs of chronic respi...
Kleine LG, Solano M, Rusckowski M, Hunt KE, Johnson KL, Kirker-Head CA.To evaluate the use of technetium Tc 99m-labeled EDTA-biotin monomer ((99m)Tc-EB1) as a scintigraphic imaging agent for soft tissue inflammatory lesions in horses. Methods: 6 healthy adult horses. Methods: First (phase 1), the agent's safety and blood-tissue clearance and an appropriate imaging protocol were determined in 6 horses. Each horse was injected with (99m)Tc-EB1 (1.1 GBq, IV, once); images were acquired at intervals during the following 24-hour period. Subsequently (phase 2), inflammation was induced via injection of 200 mg (10 mL) of mepivacaine (0.4 mg/kg) into the right neck muscu...
Vanderperren K, Saunders JH.The equine fetlock is the joint most commonly associated with lameness. Although the fetlock is regarded as a simple joint, diagnosis of a fetlock disorder can be a challenge and various imaging modalities are routinely used to arrive at an accurate diagnosis. This review describes the principal disorders affecting the soft tissues of the fetlock region and addresses some of the technical aspects involved in taking radiographic and ultrasonographic images of the different soft tissue lesions. A combination of radiography and ultrasonography is still the most commonly used diagnostic approach i...
Keppie NJ, Rosenstein DS, Holcombe SJ, Schott HC.Gastrointestinal sand accumulation is a common cause of equine colic. Subjective assessment of sand accumulation on abdominal radiographs has been used as a diagnostic aid; however, there is poor correlation between clinical, diagnostic, and surgical findings. The purpose of this study was to develop an objective method of assessing radiographic sand accumulation in order to improve the diagnostic utility of radiography for sand colic. Fifty-one equine abdominal radiographic examinations were reviewed, with approximately half of the imaged patients having a clinical diagnosis of sand colic. In...
Du Toit N, Kempson SA, Dixon PM.Post-mortem examination of 19 donkey skulls showed that donkeys have a greater degree of anisognathia (27% width difference between upper and lower jaws) compared to horses (23%). Teeth (n=108) were collected from 14 skulls and examined grossly and by computed axial tomography (CAT). A greater degree of peripheral enamel infolding was found in mandibular cheek teeth (CT) compared to maxillary CT (P<0.001). A significant increase in peripheral cementum from the apical region to the clinical crown was demonstrated in all CT (P16 years) than in the younger (<15 years) donkeys studied. Based...
Gehlen H, Haubold A, Rohn K, Stadler P.In the present study we examined, if in Icelandic horses an increase in heart and/ or breathing rate is physiological and breed dependend or a sign of a pulmonary or cardiac disease. Therefore we examined 37 Icelandic horses with the prereport of being healthy. During clinical lung examination four horses showed symptoms of a pulmonary disease like increased breathing rate and enforced breathing at rest. These horses were excluded from the study. The other 33 horses were clinically normal. 17 of these horses were unridden (untrained) and 16 horses were regularly worked (trained). After clinica...
Huthmann S, Gasse H, Jacob HG, Rohn K, Staszyk C.The equine cheek tooth battery is part of a very dynamic system. The aim of this study was to investigate whether the curvature and position of the teeth are also involved in such dynamical processes. The alveolar crest was labelled with a radiodense marker (48 cadaver heads, 15 skulls) and laterolateral radiographs were taken. Then a geometrical method was elaborated to determine a cheek tooth's curvature and its position by means of specific angles. This method respects the remarkable changes of the equine dentition throughout life by considering two items: (1) the alveolar crest was taken a...
Relave F, David F, Leclère M, Alexander K, Bussières G, Lavoie JP, Marcoux M.To evaluate use of pre-tied ligating loop to perform thoracoscopic, large lung biopsy in normal and heaves-affected horses. Methods: Prospective clinical study. Methods: Normal (n=5) and heaves-affected (n=6) horses. Methods: Lung biopsies, 1 from each hemithorax, were collected thoracoscopically using a pre-tied ligating loop. Horses were either normal (C) or heaves-affected with the latter being in remission (Ha) for the initial biopsy and in exacerbation (Hs) for the 2nd biopsy. Clinical variables, PaO(2), and PaCO(2) were used to determine the effect of surgical biopsy. Postoperative pneum...
Barakzai SZ, Kane-Smyth J, Lowles J, Townsend N.To examine 2 rostral maxillary sinus (RMS) trephine sites for safety and efficacy using skulls of horses of varying age. Methods: Descriptive study. Methods: Cadaveric equine skulls (n=40). Methods: Two RMS trephination sites (rostral, caudal) were made in each skull. Radiographic projections using markers at each site were used to determine if sites were within the RMS and directly overlying a cheek tooth. Sinusotomy in 14 skulls was used to determine correlation between radiographic and anatomic location of trephine sites, and of the rostrolateral aspect of the maxillary septum. Age-related ...
Staszyk C, Bienert A, Bäumer W, Feige K, Gasse H.To provide anaesthesia of the maxillary cheek teeth, a local block of the infraorbital nerve in the pterygopalatine fossa has been suggested. The aim of this study was to re-examine the anatomy of the pterygopalatine fossa, giving special attention to relevant arteries, veins and nerves; simulate the infiltration of an anaesthetic by injecting a contrast medium; improve the injection technique to avoid puncturing of relevant anatomical structures. Five heads and two living horses were investigated using contrast medium injections and computed tomography (CT). Needles were inserted using two in...
Wong DM, Belgrave RL, Williams KJ, Del Piero F, Alcott CJ, Bolin SR, Marr CM, Nolen-Walston R, Myers RK, Wilkins PA.5 horses were evaluated because of decreased appetite, weight loss, fever, cough, tachypnea, and respiratory distress. Results: Tachycardia, tachypnea, increased respiratory effort, lethargy, fever, poor body condition, and nasal discharge were detected in various combinations on initial physical examination. Evaluation of the lower portion of the respiratory tract via radiography and ultrasonography revealed a severe nodular interstitial pattern. Histologic examination of lung tissue revealed interstitial expansion of alveolar parenchyma with collagen, intraluminal accumulation of neutrophils...
Kummer M, Gygax D, Lischer C, Auer J.Hoof preparation and shoe fit are integral to the long term soundness and athletic ability of horses. The farrier influences the balance of the hoof by both the trimming and the shoeing procedure. The goal of this study was to investigate and quantify the influence of the farrier on hoof parameters by trimming. Forty Warmblood horses ranging in age from 6-12 years and withers height 162-172cm were included. They were divided into six groups consisting of six or seven horses each, shod by one of six different farriers. The hoofs of the horses were radiographed twice using a standardised method ...
Kruger EF, Puchalski SM, Pollard RE, Galuppo LD, Hornof WJ, Wisner ER.To define the reference range for laminar blood flow (BF) and vascular permeability (VPM) in horses without laminitis by use of dynamic contrast-enhanced computed tomography (CT). Methods: 9 adult horses that were not lame and had no abnormalities of the laminae or phalanges detectable via radiographic examination. Methods: Each horse was anesthetized by use of a routine protocol. Horses were placed in right or left lateral recumbency with the dependent forelimb in the CT gantry; only 1 limb of each horse was scanned. Serial 10-mm collimated transverse CT images were acquired at the same locat...
Fuerst AE, Oswald S, Jäggin S, Piskoty G, Michel S, Auer JA.The objective of this postmortem study was to determine the fracture configurations of the equine radius and tibia after a simulated kick. Fracture configurations of 35 radii and 36 tibiae from 19 adult horses were evaluated after a simulated kick in an experimental ex-vivo study. The bones were dissected, the proximal and distal ends were embedded in resin, fixed horizontally and preloaded in compression, and a steel impactor, designed to simulate a shod equine hoof, was dropped from a height of three to six metres onto the diaphysis. The experiments were filmed with a high-speed camera (30,0...
Edwards RB, Lu Y, Cole BJ, Muir P, Markel MD.To compare a radiofrequency energy (RFE) prototype probe to mechanical debridement (MD) and a commercially available RFE system used for chondroplasty in the treatment of an experimentally created partial thickness cartilage lesion in horses. The study design was experimental, randomized complete block, n=8, using fifteen mature ponies. Methods: Grade 2 to 3 cartilage lesions were prepared in both patellae. After 10 months duration, the injuries were used to study the effects of MD, a commercially available bipolar RFE device (CoVac 50; ArthroCare Corporation) and a prototype monopolar RFE dev...
Vilar JM, Rivero MA, Arencibia A, Morales I, Pinedo M.The authors propose a standard protocol of ultrasonographic exploration of the tarsal region in transversal and longitudinal planes, with the aim to spread with an accurate location of the anatomical structures. For this study, 10 adult horses of different races and ages (ranged 5-10 years) were used, with the characteristic of not having suffered any kind of tarsic pathology. The equipment was a real time ultrasound machine with a 7.5 mHz lineal transducer. Some different anatomical structures in this region of the hind-limb such as the tendons, ligaments, muscles and articular components wer...
Donabédian M, van Weeren PR, Perona G, Fleurance G, Robert C, Léger S, Bergero D, Lepage O, Martin-Rosset W.Diagnosis of osteochondrosis (OC) is based on clinical signs and radiography, but alternative methods for detection at an early stage would be useful. Objective: To determine in the juvenile horse the relationship between serum concentrations of a number of biomarkers that reflect changes in cartilage and bone turnover and age, feeding level, growth, and the occurrence of OC. Methods: Foals were assigned to a high (n = 20) or moderate (n = 19) feeding level group from birth to age 1 year. Bodyweight, withers height and cannon width were measured. Osteoarticular status was assessed radiographic...
Back W, van der Lugt JJ, Nikkels PG, van den Belt AJ, van der Kolk JH, Stout TA.An extreme form of abnormal development, dwarfism, is common in man and some animals, but has not been officially reported in horses. Within the Friesian horse breed, congenital dwarfism has been recognised for many years, but no detailed report exists on its phenotype. The most salient feature of the dwarf syndrome is the physeal growth retardation in both limbs and ribs. Affected animals have approximately 25% shorter fore- and hindlimbs and approximately 50% reduced bodyweight. Postnatal growth is still possible in these animals, albeit at a slower rate: the head and back grow faster than t...
Tomlinson JE, Sage AM, Turner TA, Feeney DA.To map the equine pelvis using ultrasonography, validated by use of computed tomography (CT), magnetic resonance imaging (MRI), and measurements of frozen cadaver slices. Methods: 6 ponies and 6 horses. Methods: Ultrasonographic examination of the pelvis was performed on 6 clinically normal ponies. Measurements were obtained for imaged structures. Computed tomography, MRI, and measurements of frozen sections were performed after death and used to verify measurements. Linear regression determined the degree of correlation between measurements obtained ultrasonographically and the other modaliti...
Ladefoged S, Grulke S, Busoni V, Serteyn D, Salciccia A, Verwilghen D.To describe the management and outcome of limb fractures in small domestic equids treated with a modified Thomas splint-cast combination (MTSCC). Methods: Retrospective case series. Methods: Client owned horses and donkeys. Methods: Medical records, including radiographs, were reviewed for details of animals diagnosed with a limb fracture and treated by external coaptation using a MTSCC (2001-2012). Follow-up >6 months after discharge was obtained via telephone consultation with owners or veterinarians. Results: Nine horses and 4 donkeys were identified with fractures of the tibial diaphysi...
Faramarzi B, Salinger A, Kaneps A, Nout-Lomas Y, Greene H, Dong F. The goal of this study was to quantify external and internal anatomical characteristics of the foal foot throughout the first year of age. Digital radiographs and photographs were taken bimonthly of the forefeet of nine Arabian foals, beginning at about 2 weeks of age until 12 months of age. Sixty-eight linear and angular variables were measured using NIH (National Institutes of Health) software. Statistical analyses were performed using piecewise random coefficient model and -values < 0.05 were considered significant. Distinct changes in hoof development were identified betwe...
Furniss C, Carstens A, van den Berg SS.This study involves the evaluation of pre-purchase radiographic studies of South African Thoroughbred yearlings. Radiographic changes were recorded and compared with similar international studies. The study differs from other studies in that a lower prevalence of pedal osteitis (1.26%), dorsal osteochondral fragmentation of the metatarsophalangeal joint (1.60%), distal metacarpal sagittal ridge changes (15.7%), ulnar carpal bone lucencies (8.33%), carpal osteophytes (1.19%), distal intertarsal and tarsometatarsal joint radiographic changes (9.92%), tarsal osteochondrosis lesions (4.40%) and st...
Brauer TS, Booth TS, Riedesel E.Retrospective analysis of the radiographs of horses with carpal valgus, presented to the Iowa State University Veterinary Teaching Hospital from 1987-1996, were used to compare 2 methods of geometric analysis for finding the total angle of deviation. The pivot point angle method and the individual joint angle method were found to be comparable for determining the total angle of deviation. The individual joint angle method was used to analyse individual carpal joint angles and physis angle in joints with carpal valgus, as well as the changes that occurred in response to surgical correction. Mul...
Lewis AJ, Sod GA, Burba DJ, Mitchell CF.To compare compression pressure (CP) of 6.5 mm Acutrak Plus (AP) and 4.5 mm AO cortical screws (AO) when inserted in simulated lateral condylar fractures of equine 3rd metacarpal (MC3) bones. Methods: Paired in vitro biomechanical testing. Methods: Cadaveric equine MC3 bones (n=12 pair). Methods: Complete lateral condylar osteotomies were created parallel to the midsagittal ridge at 20, 12, and 8 mm axial to the epicondylar fossa on different specimens grouped accordingly. Interfragmentary compression was measured using a pressure sensor placed in the fracture plane before screw placement for ...
Jarvis KA, Steffey EP, Tyler WS, Willits N, Woliner M.Results of recent investigations in humans and dogs indicate that gravity-independent factors may be important in determining the distribution of pulmonary blood flow. To further evaluate the role of gravity-independent factors, pulmonary blood flow distribution was examined using 15-microns radionuclide-labeled microspheres in five prone ponies over 5 h of pentobarbital sodium anesthesia. The ponies were killed, and the lungs were excised and dried by air inflation (pressure 45 cmH2O). The dry lungs were cut into transverse slices 1-2 cm thick along the dorsal-ventral axis, parallel to gravit...
Harding PG, Smith RL, Barakzai SZ.To compare two approaches to performing the inferior alveolar nerve block in the horse and to evaluate the consistency of described topographical landmarks. Methods: Experimental cadaver model. Methods: Eleven cadaver heads were positioned to mimic a standing sedated horse and the position of the mandibular foramen approximated. The vertical approach to the approximate location of the mandibular foramen was undertaken and red dye was deposited. The angled approach was then undertaken and blue ink was used to identify it. The heads were then dissected to determine the location of the dye. Place...
Riley CB, Scott WM, Caron JP, Fretz PB, Bailey JV, Barber SM.The clinical features, radiographic findings, treatment, and outcome in 51 draft horses with osteochondritis dessicans (OCD) or subchondral cystic lesions (SC) are reported. Clydesdale and Percheron were the most commonly affected breeds, and affected animals represented only 5% of the hospital population of draft horses. Horses were most frequently affected in the tibiotarsal joints and 73% (24 of 33 cases) of the horses with tibiotarsal effusion were affected bilaterally. Osteochondritis dessicans of the distal intermediate ridge was the most common lesion found in the tibiotarsal joint. The...
Hargreaves L, Dixon JJ.Oronasal and oromaxillary sinus fistulae are well-documented complications following removal or loss of a maxillary cheek tooth. Diagnosis is currently based on a combination of oral examination, videoendoscopy, radiography, and computed tomography (CT). The objective of this retrospective, case series study was to describe the CT characteristics of confirmed oronasal and oromaxillary sinus fistulae in a group of horses. Inclusion criteria were a head CT acquired at the authors' hospital during the period of 2012-2017, a CT diagnosis of oronasal or oromaxillary sinus fistulae, and a confirmed ...
Russell JW, Hall MS, Kelly GM.A 3-year-old Thoroughbred gelding was presented with a grade 3/5 lameness of the right forelimb and effusion of the extensor carpi radialis tendon sheath (ECRTS). Radiographic and ultrasonographic examinations revealed an osteochondroma on the cranial aspect of the distal radius projecting into the fibrous lining of the ECRTS. An open surgical approach was used to remove the osteochondroma and some of the proliferative synovial tissue. Conclusions: Six months after surgery the clinical signs had resolved and the horse raced successfully.
Miyakoshi D, Senba H, Shikichi M, Maeda M, Shibata R, Misumi K.This study aimed to evaluate whether radiographic abnormalities at yearling sales were associated with the failure to start racing at 2-3 years of age. Radiographic abnormalities in the carpal (n=852), tarsal (n=976), metacarpophalangeal (n=1,055), and metatarsophalangeal joints (n=1,031) from 1,082 horses, recorded at yearling sale, were reviewed. Eighty-two horses (7.6%) failed to start racing. Radiographic abnormalities such as wedged or collapsed tarsal bones, irregular lucency of a sagittal ridge at the distal aspect of the distal third metatarsal bone, and proximal dorsal fragmentation o...
Stover SM, Hornof WJ, Richardson GL, Meagher DM.History, physical examination, and bone scintigraphy were used to diagnose central and/or third tarsal bone trauma in 3 acutely lame horses. In all 3 cases, the results of initial radiographic examination were negative. Bone scintigraphy revealed focal, intense radioisotope uptake at the level of the distal tarsal bones in the 3 horses. Radiographs obtained 4 weeks after injury in one horse demonstrated a slab fracture of the central tarsal bone. Conservative management of the tarsal bone disease resulted in acceptable return to function in all 3 horses.
Drum MG, Les CM, Park RD, McIlwraith CW, Kawcak CE.To evaluate whether cutting equine subchondral bone to demarcate specific regions of interest (ROIs) influences the mean density for that bone as measured via quantitative computed tomography (QCT). Sample population-2 metacarpophalangeal joints from equine cadavers. Methods: The distal portion of the third metacarpal bone of each intact metacarpophalangeal joint was scanned via CT to simulate in vivo conditions. Each joint was subsequently disarticulated and dissected, and the distal portion of the dissected third metacarpal bone in air was scanned. Then, six 1-cm(2) areas representing ROIs w...
Mair TS, Kinns J.Injury to the distal aspects of the deep digital flexor tendon (DDFT) is an important cause of lameness in horses. The purpose of this study was to review the magnetic resonance imaging (MRI) findings of 18 horses affected by DDFT injuries in the foot. The MRI was performed with the horses standing using an open low-field (0.21 T) MRI scanner. The results were compared with those previously reported for horses using high-field MRI. Eighteen of 84 horses (21%) with undiagnosed forefoot pain were found to have lesions affecting the DDFT. The history, clinical findings and results of radiography,...
Hall S, Smith R, Ramzan PHL, Head M, Robinson N, Parker R.Rib fractures in adult horses are poorly documented. Objective: To describe the presenting signs, diagnosis, treatment and outcome of horses diagnosed with rib fracture. Methods: Retrospective case series. Methods: The clinical records and diagnostic images of all adult horses diagnosed with a rib fracture at three referral centres over a 15-year period were reviewed. Results: Seventy-three horses met the inclusion criteria. Horses presented due to either resistance to ridden work and poor performance (n = 41), lameness (n = 21) or trauma (n = 7). In four horses, the presenting complaint...
Doyle PS, White NA.To determine clinical, scintigraphic, radiographic, and arthroscopic findings and results of treatment in horses with lameness attributable to subtle osteochondral lesions of the shoulder joint. Methods: Retrospective study. Methods: 15 horses. Methods: Medical records were reviewed, and results of physical examination, scintigraphy, radiography, arthroscopy, and treatment were recorded. Results: Severity of lameness ranged from grade 1 to 4. Response to shoulder flexion or extension was variable. Twelve horses had a narrow upright foot. Intra-articular anesthesia of the shoulder joint localiz...
Steckel RR.Bone scanning to help diagnose orthopedic disease has been used in human patients for over two decades. The value of this diagnostic tool has been well established in helping to identify a variety of musculoskeletal conditions. It has only recently been used by veterinarians for more accurate characterization of equine musculoskeletal disease. The technique offers the major advantage of increased sensitivity over standard radiographic imaging. The case material illustrated here shows that except for consistent identification of bone cysts, most of the pathologic changes to the horse's musculos...
Orsini PG, Raker CW, Reid CF, Mann P.The normal radiographic anatomy of the equine larynx was determine by use of xeroradiography and dissection. The body and laminae of the thyroid cartilage, the muscular process of the arytenoid cartilages, and the dorsal lamina and arch of the cricoid cartilage had radiographic evidence of mineralization (calcification) and/or ossification in clinically normal horses. There was a significant (P less than 0.01) increase in the degree of mineralization of the thyroid and arytenoid cartilages with advancing age. Horses with diagnosis of arytenoid chondrosis (arytenoid chondral dysplasia, arytenoi...
Dik KJ, van den Belt AJ, van den Broek J.Estimating the shape of the proximal articular border of the navicular bone and grading the radiological navicular bone condition (grades 3 and 4 representing the most severe changes), the aim of this study was to assess potential age-related implications of the previously reported shape predisposition to navicular disease in 746 normal and 174 clinically affected Dutch Warmbloods age 3-19 years. A significant, age-independent, shape-grade association found in normal and affected horses emphasises the fundamental character of the shape predisposition to navicular disease. A significant age-rel...
Ramos S, Pinto A, Crespo J, Marques JP, Bettencourt E, Gama LT, Monteiro S.Osteochondrosis (osteochondritis dissecans), OC(D), is an important joint disorder that has been studied through the years in different breeds but, to our knowledge, there are no reports of its prevalence in Lusitano horses. The aim of this study was to assess the prevalence of OC(D) in Lusitanos, define the characteristics of the disorder in this breed and compare with Spanish Purebred horses. This is a retrospective study that analysed the radiographs from the metacarpometatarsophalangeal, tarsocrural and femoropatellar joints that were taken in 302 Lusitano horses (1-12 years; obtained from...
Verschooten F, Roels J, Lampo P, Desmet P, De Moor A, Picavet T.Radiographic measurements from the lateromedial projection of the equine foot were compared in three groups of horses. Group 1 consisted of 143 normal horses, group 2 were 60 horses with clinical navicular disease and group 3 were 161 horses with clinical and radiographic navicular disease. Several measurements tended to be larger in group 3 than group 1. An enlargement of the navicular bone was observed in proximodistal and dorsopalmar directions. Partial enlargement of the pedal bone was observed in groups 2 and 3. Few differences were observed between age classes. All horses aged four years...
Dyson S, Murray R.Nuclear scintigraphy is commonly used as a diagnostic aid for foot pain, but there is limited information about different patterns of radiopharmaceutical uptake (RU) and their correlation with the results of other imaging modalities. Objective: To describe patterns of RU in horses with foot pain. Methods: Scintigraphic images of the feet of 264 horses with front foot pain were analysed subjectively and using region of interest analysis. Magnetic resonance images of all feet were analysed prospectively; the navicular bones were reassessed retrospectively and assigned a grade. A Spearman rank co...
Bryant HA, Dixon JJ, Weller R, Bolt DM.The diagnostic value of positive contrast radiography in the work-up of suspected synovial infection in horses with limb wounds near synovial structures has yet to be systematically evaluated. Objective: To determine the specificity, sensitivity and positive and negative predictive values of positive contrast radiography for identification of synovial infection in a population of horses with limb wounds. Methods: Retrospective case study comparing the performance of positive contrast radiography to the gold standard of synovial fluid cytology in horses presenting with limb wounds in the vicini...
McKlveen TL, Jones JC, Sponenberg DP, Scarratt K, Ward DL, Aardema CH.To describe the anatomic features of the pituitary gland region in horses via computed tomography (CT) and determine the accuracy of CT for estimating normal equine pituitary gland dimensions. Methods: 25 adult horses with no clinical signs of pituitary disease. Methods: Transverse CT images and gross transverse tissue sections were compared in 2 horses. Contrast-enhanced CT of the pituitary gland region was performed postmortem in 23 horses with 4 slice thickness and interval settings (10-mm contiguous or overlapping slices and 4-mm contiguous or overlapping slices). Gross and CT estimates of...
Cruz AM, Pharr JW, Bailey JV, Barber SM, Fretz PB.To evaluate podotrochlear bursa (navicular bursa) endoscopy as a diagnostic technique in horses and to correlate observations to radiographic and pathologic findings. Methods: Descriptive study. Methods: Seventeen equine cadaver forelimbs. Methods: Five standard radiographic views of the navicular region and a bursographic study with lateromedial and caudal tangential radiographic views were taken of each forelimb. Radiographic scoring of the navicular bone (0, excellent; 1, good; 2, fair; 3, poor) was performed using a previously reported technique. Endoscopic examination was performed using ...
Bos H, van der Meij GJ, Dik KJ.Bone structure, nutrient canals, form and definition, and a total evaluation of both fore navicular bones were radiologically evaluated in 169 three- and four-year-old Dutch warmblood mares divided into eleven daughter (half sister) groups. On the basis of the 'total evaluation', differences between the three- and four-year-old horses were detectable. Using the 'total evaluation', significant differences were found between daughter groups consisting of three-year-old mares. These differences support the theory that podotrochleosis may be (partly) due to the presence of genetic factors. The pos...
Crawley GR, Grant BD, White KK, Barbee DD, Gallina AM, Ratzlaff MH.A modified Cloward's technique was performed for arthrodesis of one metacarpophalangeal (MCP) joint in eight horses. Dorsal arthrotomies were performed medial and lateral to the common digital extensor tendon and two 16 mm holes were drilled through the joint. A perforated cylindrical stainless steel basket filled with cancellous bone was impacted into each hole. The limbs were supported in casts for 8 weeks. The joints were examined and radiographed at 4 weeks, 8 weeks, 6 months, and 10 months. One horse was euthanatized at week 14 to assess the progress of the arthrodesis. In the other seven...
Cohen JM, Southwood LL, Engiles J, Leitch M, Nunamaker DM.To examine the efficacy and biocompatibility of a thiolated gelatin-thiolated carboxymethyl hyaluronan (CMHA-SGX) sponge as an osteoconductive device in an equine second and fourth metacarpal bone defect model. Methods: Seven millimetre segmental ostectomies were created bilaterally in the second and fourth metacarpal bones of four horses. The left and right metacarpal defects were randomly assigned to (1) be filled with a CMHA-SGX sponge (treated) or (2) were left unfilled (control). The duration of the study was nine weeks. Bone healing was evaluated using serial radiology, as well as histol...
Gorgas D, Luder P, Lang J, Doherr MG, Ueltschi G, Kircher P.Nuclear bone scintigraphy is commonly used in the diagnosis of sacroiliac disease in horses. The aim of the present retrospective study was to determine if there was an association between radiopharmaceutical uptake pattern and radiographic appearance of the sacroiliac region in horses. Seventy-nine horses undergoing bone scintigraphy with Tc-99 m-HDP and radiography of the pelvis because of lameness or poor performance were studied. Subjective and semiquantitative methods were used to characterize and compare radiopharmaceutical uptake between horses. Ventrodorsal radiographs of the region we...
