The skeletal system in horses comprises a complex structure of bones that provide support, protection, and mobility. Equine bones are involved in various physiological functions, including mineral storage and hematopoiesis. The bone structure in horses is categorized into different types, such as long bones, short bones, flat bones, and irregular bones, each serving specific roles in movement and stability. Research in this area explores topics such as bone development, remodeling, and the impact of nutrition and exercise on bone health. This page gathers peer-reviewed studies and academic articles that focus on the anatomy, physiology, and pathology of bones in horses, offering insights into conditions such as fractures, bone diseases, and the effects of aging on the equine skeletal system.
Park RD, Morgan JP, O'Brien T.The incidence of chip fractures in carpal bones and the distal end of the radius in the horse was determined. The radial carpal bone was involved 50% of the time, with the distal end of the radius and intermediate and 3rd carpal bones being involved less frequently. Nine locations were designated where chip fractures in the carpus occurred most often.
A higher incidence of fractures was noticed from the right carpus, with slab fractures of the 3rd carpal bone being noticed more frequently on the right front limb.
Petterson H, Reiland S.The research investigates a specific bone lesion called “periarticular subchondral bone cyst” in horses, based on 14 case studies conducted between 1949 and 1967. Participants and Methodology The study involved […]
Jackson MA, Ohlerth S, Fürst AE.To describe the use of an aiming device (AD) and computed tomography (CT) for preoperative planning and intraoperative guided debridement of subchondral cystic lesions (SCL) in the limbs of horses and to determine the outcome 12 months after surgery. Methods: Prospective case series. Methods: Twelve horses referred because of lameness caused by 1 or 2 SCL (total of 14 SCL). Methods: All horses underwent CT-guided debridement of the SCL. The entry point of the drill bit and direction of drilling were planned and controlled by using a series of CT images and the AD. The SCL were curetted and fil...
Davies HM.In Thoroughbred racehorses, the dorsal cortex (DC) of the third metacarpal bone (MC3) enlarges when horses are first exposed to fast exercise speeds. It is now possible to measure ultrasound speed through 3 to 5 mm depths of bone around the bone shaft using Sunlight Medical's 'Omnisense' machine. The aim of this experiment was to determine whether the ultrasound speed measured in the surface 3-5 mm of the midshaft dorsal cortex of MC3 could be related directly to the midshaft shape and size of the MC3s of young Thoroughbred racehorses at the same stage of training. Sixteen 2-year-old and sixte...
Gardner AK, Santschi EM, Mudge MC, Belknap JK, Metzler AG.To describe the repair of unstable facial fractures by using Foley catheter balloons as intrasinus bolsters. Methods: Case report ANIMALS: Two weanling foals with unilateral fractures of the sinus and orbit secondary to kick injuries. Preoperative imaging that included positive contrast dacrocystorhinography and computed tomography confirmed severe comminution of facial fractures and nasolacrimal duct disruption in both foals. Methods: Small bone fragments were surgically removed, and large fragments were retained even when denuded of periosteum. Repair procedures included nasolacrimal canalic...
Simpson CM, Lumsden JM.A 2-year-old Thoroughbred gelding was evaluated for a grade 3 out of 5 unilateral hind limb lameness. Flexion of the right hock and stifle joints (spavin test) exacerbated the lameness. Response to intra-articular and perineural anaesthesia isolated the source of lameness to the tarsocrural area, despite an absence of tarsocrural joint effusion. Routine radiographic examination of the hock did not reveal any significant abnormalities. Skeletal nuclear scintigraphic evaluation revealed a focal region of increased bone activity in the proximal medial trochlear ridge of the talus. Flexed laterome...
Elane GL, Biedrzycki AH, McCarrel TM, Banks SA, Morton AJ.To quantify the translation and angular rotation of the distal sesamoid bone (DSB) using computed tomography (CT) and medical modeling software. Methods: 30 thoracic limbs from equine cadavers. Methods: Partial (n = 12), full (8), and matched full and subsequently transected (10) thoracic limbs were collected. Bone volume CT images were acquired in three positions: extension (200° metacarpophalangeal angle), neutral (180°), and maximal flexion (110°). Mean translation and angular rotation of each DSB were recorded. Differences were determined with two-way ANOVA and post hoc Tukey's tests fo...
Xin CR, Bai S, Qin ZJ, Gao JS, Lin ZQ, Cheng YB.To study the morphological characteristics of femurs of adult human and 11 kinds of adult animals from cattle, horses, pigs, goats, sheep, dogs, cats, rabbits, geese, ducks, chickens, and to establish an effective species identification method among various species. Methods: The 4 cm mid-diaphyseal segment of the femur from adult human (older than 20 years old) at autopsy was obtained. Addi-tionally, the 4 cm ones from 11 kinds of adult animals were obtained. After decalcification, all femurs were made into slices, and then were observed by optical microscope. The 25 indexes were selected and ...
Grabski M, McNamara J, Roper D, Warren-Smith C, Busschers E.To describe the volume and dimensions of the bicipital bursa and its position in relation to bony and soft tissue structures, in order to develop a novel medial synoviocentesis approach to the bicipital bursa. Methods: Cadaveric study. Methods: Adult equine cadaver limbs (n=19). Methods: Bicipital bursa dimensions, volume, and relationship to bony structures were obtained from positive contrast computed tomography images after distension of the bursa (n=7). Following an intra-bursal injection of polyurethane resin, the bicipital bursa (n=4) was dissected and its relationship to soft tissue str...
Sod GA, Hubert JD, Martin GS, Gill MS.To compare biomechanical properties of a prototype 5.5 mm tapered shaft cortical screw (TSS) and 5.5 mm AO cortical screw for an equine third metacarpal dynamic compression plate (EM-DCP) fixation to repair osteotomized equine third metacarpal (MC3) bones. Methods: Paired in vitro biomechanical testing of cadaveric equine MC3 with a mid-diaphyseal osteotomy, stabilized by 1 of 2 methods for fracture fixation. Methods: Adult equine cadaveric MC3 bones (n=12 pairs). Methods: Twelve pairs of equine MC3 were divided into 3 groups (4 pairs each) for (1) 4-point bending single cycle to failure testi...
Norton NM, Santschi E, Fischer KJ.The etiology of subchondral bone cysts (SBCs) is not fully understood. Mechanical trauma and fluid pressure are two mechanisms believed to cause their formation and growth. The equine stifle joint provides a natural animal model for studying SBCs. Computed tomography images of an extended yearling cadaveric stifle joint were segmented using ScanIP to isolate bones and relevant soft tissues. Three model geometries were created to simulate cyst sizes of approximately 0.03 cm (C1), 0.5 cm (C2), and 1 cm (C3). A uniform pressure resulting in 3000 N force was applied at the proximal end of the fem...
Chans-Veres J, Albiñana-Cunningham J, Quintela JM, Pereira E, Tejero S.Surgery for severe equine cavo-varus is complex and must be individualized. The interindividual phenotypic variability demands a personalized planning of each foot to be operated. The study's primary goal was to evaluate the function and satisfaction of a series of patients with severe equinus cavo-varus deformity who underwent a triplanar tarsectomy and transposition of the posterior tibial tendon in a single stage surgery after a patient specific 3D biomodel planning. A series of 12 feet (5 patients bilaterally) operated with this technique was analyzed. The cohort comprised 2 females (28.5 ...
Davies HM.The relationships were explored between measurements of bone quality, size (quantity) and shape, and strain data collected during treadmill exercise at 4 and 12 m/s from the third metacarpal bones of 6 yearling and 6 mature Thoroughbred racehorses. Peak strains in yearling and mature Thoroughbred horses during exercise were related to the size and shape of the third metacarpal bone. The peak strains were significantly lower in horses with a greater cross-sectional area of bone and with a greater proportion of the bone in the dorsal cortex. There was no consistent relationship between peak stra...
Ekman S, Skiöldebrand E, Heinegård D, Hultenby K.One of the most common causes of lameness in racehorses is osteoarthritis (OA). Pathogenesis is not clear and pathological processes of the different joint tissues interact in often progressive events. The interface between cartilage and newly synthesised bone has been shown to be particularly enriched in bone sialoprotein (BSP), a cell-binding matrix protein. Objective: To establish whether changes in the concentration of BSP may serve as a marker for early biochemical changes of the subchondral bone. Methods: Articular cartilage, cartilage/bone interface and subchondral bone of the proximal ...
Ball AN, Hoaglund EL, Pool R, Barrett MF, Bass LD.Lameness remains a common cause of retirement in the equine athlete and among hobby enthusiasts. The distal limb is one of the most frequently imaged areas, and recent advances in diagnostic imaging capabilities help practicing veterinarians differentiate normal variants from informative pathology. Although acute, non-weight-bearing lameness is commonly associated with etiologies, such as fractures, abscesses, and laminitis, other uncommon differentials such as cystic lesions and neoplasia might also be considered. This report describes the characterization of a large, cystic lesion in the thi...
Sedrish SA, Moore RM, Kelly K, Martin GS, Burba DJ.To determine and compare the in vitro pullout strength of 5.5-mm cortical versus 6.5-mm cancellous bone screws inserted in the diaphysis and metaphysis of adult equine third metacarpal (MCIII) bones, in threaded 4.5-mm cortical bone screw insertion holes that were then overdrilled with a 4.5-mm drill bit to provide information relevant to the selection of a replacement screw if a 4.5-mm cortical screw is stripped. Methods: In vitro pullout tests of 5.5-mm cortical and 6.5-mm cancellous screws in equine MCIII bones. Methods: Two independent cadaver studies each consisting of 14 adult equine MCI...
Raspanti M, Guizzardi S, Strocchi R, Ruggeri A.Samples of compact bone were deproteinated by heat treatment and analysed by SEM. This technique removes very effectively cells and vascular structures and brings into full view the mineralization front along the wall of the Havers canal. The present study was confined to samples of equine bone that are known to be subjected to different functional requirements. Bone subjected to high tensile stress exhibited collagen fibrils substantially aligned with the stress direction, and the vast majority of its osteons appeared made of almost parallel fibrils crossing at very narrow angles. On the cont...
Rocconi RA, Carmalt JL, Sampson SN, Elder SH, Gilbert EE.This study compared in vitro monotonic and cyclic mechanical properties of equine proximal interphalangeal joint arthrodeses stabilized using an open or closed technique combined with axial 4.5 mm narrow limited-contact dynamic compression plate (LC-DCP) or 4.5 mm narrow locking compression plate (LCP). Ten forelimb pairs were randomly assigned to LCP or LC-DCP groups. One limb in each pair was assigned to either open or closed technique. Limbs were tested for cyclic fatigue at 20 000 cycles and then single-cycle to failure under 3-point dorsopalmar bending. There was no significant difference...
Pelli AC, Winter K, Offhaus J, Brehm W, Gerlach K.In equine skeletal scintigraphy, there is no information about the possible influence of different phosphonate compounds on image quality. This prospective randomised study determined bone uptake changes and image quality for hydroxymethylene diphosphonate (HDP) and methylene diphosphonate (MDP) in equine patients at different time points. Scintigraphic images of the radius and the tibia of 20 horses were acquired at 2 and 4 hours after injection of either technetium-labelled HDP or MDP. Three regions of interest were identified-in the bone diaphysis, adjacent soft tissue and background area-t...
Martinelli MJ, Baker GJ, Clarkson RB, Eurell JC, Pijanowski GJ, Kuriashkin IV, Carragher BO.To expand our current knowledge and to establish limits of correlation between signal intensities of the magnetic resonance (MR) image and actual macroscopic and microscopic anatomic features of the imaged structures of the equine metacarpophalangeal joint (MCPJ). Methods: The right MCPJ was obtained from 4 adult horses that were euthanatized for reasons unrelated to the musculoskeletal system. Methods: The distal portion of the right forelimbs was collected from 4 equine cadavers. The bones were drilled to provide fixed reference points and examined by MR imaging. After imaging, the joints we...
Dimock AN, Spriet M.The effect of the chemical shift artifact, resulting from misregistration or phase cancellation at the interface between compact and trabecular bone, on apparent bone thickness was quantified in six isolated equine limbs. Sagittal T1-weighted spin echo (SE) and in-phase three-dimensional spoiled gradient echo (SPGR) images were acquired twice with a 1.5 T magnetic resonance (MR) unit, switching the frequency encoding direction between acquisitions. Out-of-phase SPGR images were also obtained. MR images with different frequency encoding directions were compared with each other and to radiograph...
Janicek JC, Carson WL, Wilson DA.The purpose of this investigation was to design and verify the capabilities of an in vitro loading-measurement system that mimics in vivo unconstrained three dimensional (3D) relative motion between long bone ends, applies uniform load components over the entire length of a test specimen, and measures 3D relative motion between test segment ends to directly determine test segment construct stiffness free of errors due to potting-fixture-test machine finite stiffness.Intact equine cadaveric radius bones, which were subsequently osteotomized/ostectomized and instrumented with bone plates were su...
Turner AS, Milne DW, Gabel AA.Long-bone fractures of 6 foals admitted consecutively to the Ohio State University Veterinary Hospital were treated successfully with ASIF dynamic compression plating. The cases included 2 foals with closed fracture of the metacarpus, and 1 foal each with open nonunion of the metatarsus, closed fracture of the radius, open fracture of the tibia, and open fracture of the ulna. Five of these foals became sound, with no deformity, so they could be trained for racing or showing. The 6th foal, a filly with nonunion, became "pasture-sound" and was scheduled for breeding. It was concluded that the dy...
Gfrerer L, Michel S, Fürst AE, Piskoty G, Weisse B, Montavon S, Jackson MA. The goal of this study was to generate mandibular fractures in three regions of the diastema using a metal impactor to simulate a kick from a horse and to determine the mean deceleration in the initial phase of the impact event, the maximum contact force, the impact energy necessary to create a fracture and the duration of the impact. Methods: Thirty heads of horses aged between 5 and 20 years and euthanatized for various reasons were used. The heads were attached to a steel bar at the occiput at an axial angle of 45 degrees so that the body of the mandible was positioned horizontally ...
Tulloch PJ, Johnston JD, Barber SM, Gellert CL, Lang HM, Panizzi L.To determine degrees of flexion after arthrodesis of the antebrachiocarpal (ABC) joint, middle carpal (MC), and carpometacarpal (CMC) joints combined (MC/CMC), and carpometacarpal (CMC) joint alone. Methods: Ex vivo study. Methods: Forelimbs (n = 9) from 2- to 10-year-old Quarter Horses (5), Thoroughbred (2), and American Paint Horse (2). Methods: Using 2 locking compression plates, 3 partial carpal arthrodesis techniques were performed. Cables and deadweights were connected to limbs and each angle of flexion determined 3 times using a protractor and then averaged. Control measurements were ob...
Häni H, Lang J, Ueltschi G.During archaeological excavations of the former knackers yard in Emmen (Canton Lucerne) skeletons and individual bones of more than 700 animals were recovered. 110 bone samples had lesions and were examined macroscopically and radiologically, 100 were from horses, 9 from dogs and only one from cattle. According to morphological and etiopathogenetical criteria, lesions are presented in the following groups: tooth irregularities (10), degenerative changes in bones and joints due to overload and aging (80), trauma and infection (10), other lesions (10). Over 80% of pathological bone samples prese...
Rangel JPP, de Oliveira APL, Baiotto GC, Junior OS, Figueiró GM, Araujo AL, Rossi Junior JL.Campylorrhinus lateralis, also known as "wry nose," is a congenital malformation that mainly affects Thoroughbreds. These horses have a unilateral deviation of the maxillae that may be to one side or the other side, and it causes airway obstruction and dental malocclusion. The choice of treatment is not necessarily operation; however, the treatment of choice, which aims to repair the maxillae deviation, is surgical to improve the horse's respiratory condition and correct the dental occlusion. There are currently no reports describing the first surgical technique for such deformity described by...
Nelson NC, Zekas LJ, Reese DJ.As availability increases and cost decreases, digital radiograph systems become more common in equine practice. Technological advances provide an array of choices for the equine practitioner considering purchase. Two classes of systems are available: computed radiography and flat-panel systems (direct radiography). Image processing encompasses all manipulations performed on an image at acquisition and can have a profound effect on the final digital radiograph. Consideration should be given to the type of display monitor because many options are now available. The type of display monitor and th...
Booth TM, Clegg PD.An 8-year-old show-jumper gelding was referred for examination as a result of a purchase dispute for reported back pain. Clinical examination identified back pain and atrophy of the left semimembranosus and semitendinosus muscles, but no lameness. Standing pelvic radiography demonstrated a chronic nonunion fracture of the left ischium, the clinical significance of which was uncertain. The apparent back pain was thought to be probably unrelated to the pelvic lesion. We conclude that chronic ischial fracture in the horse can lead to specific atrophy of the semimembranosus and semitendinosus musc...
Farr AC, Hawkins JF, Baird DK, Moore GE.To characterize features of diagnosis, treatment, and outcome in horses with foreign bodies, exclusive of enteric, inhaled, and foot-penetrating foreign bodies. Methods: Retrospective case series. Methods: 37 horses with foreign bodies. Methods: The incidence of equine foreign bodies from 1990 through 2005 was determined by review of data from veterinary schools participating in the Veterinary Medical Database (VMDB). Medical records of horses with foreign bodies at Purdue University were reviewed, and the following information was retrieved: clinical history; signalment; results of physical, ...
Rutherford DJ, Textor J, Fretz PB.A 4-week-old Thoroughbred filly presented with lameness of acute, severe onset of the left foreleg (LF) of 3 days' duration. Results: Diffuse swelling was present around the distal radius and carpus of the LF. Carpal varus that could be reduced manually was present. Radiographs revealed an intra- articular frontal-plane fracture in the distal radial epiphysis, which continued cranially through the distal radial physis (DRP). The lateral aspect of the DRP was wider than expected. Latero-medial carpal instability was resolved by placement of a lag screw from the dorsal midline through the epiphy...
Stolk PW, Firth EC.Eight metatarsophalangeal (fetlock) joints were studied in anaesthetized young ponies. Pressure measurements were made in the joint and at various sites in the marrow cavity of the third metatarsal bone with simultaneous measurement of systemic arterial and venous blood pressures. Fetlock joint flexion was always associated with a statistically significant initial decrease in intra-articular pressure (p < 0.05) followed by a marked increase in pressure (p < 0.05). Subsequent extension was accompanied by a similar pressure pattern, although there appeared to be a hysteretic relationship. ...
