Ligaments in horses are fibrous connective tissues that connect bones to other bones, providing stability and support to the skeletal structure. These structures are integral to maintaining joint function and facilitating movement. In equine anatomy, ligaments are involved in various functions, including supporting the limbs and allowing for efficient locomotion. Common ligaments in horses include the suspensory ligament, which plays a significant role in supporting the fetlock joint, and the nuchal ligament, which supports the head and neck. This page compiles peer-reviewed research studies and scholarly articles that explore the anatomy, function, injury mechanisms, and rehabilitation of ligaments in horses.
Probst A, Macher R, Hinterhofer C, Polsterer E, Guarda IH, König HE.This study aims to elucidate the topographical anatomy of the carpal flexor retinaculum or palmar anular carpal ligament (PACL) in the horse. Ten specimen of the carpus of five healthy horses were studied by dissection in layers. Slices of 5 mm in thickness facilitated observation of the soft tissues. The superficial layer of the PACL subdivides into five compartments: one for the palmar nerve and the arterial and venous branches, one for only the radial artery, one for the radial vein, and one for the tendon of the radial carpal flexor muscle, and finally for the deep layer that supports all ...
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...
Waselau M, Sutter WW, Genovese RL, Bertone AL.To determine outcome of Standardbred racehorses with moderate to severe midbody suspensory ligament desmitis (MSD) treated by means of ultrasound-guided intralesional injection of a single dose of platelet-rich plasma (PRP) followed by a program of gradually increased exercise. Methods: Nonrandomized clinical trial. Methods: 9 Standardbred racehorses. Methods: Following injection of PRP, horses were allowed a controlled, gradual return to exercise. Race records for the year prior to injury and for 3 consecutive years after horses returned to racing were reviewed. For comparison purposes, race ...
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...
Agut A, Martínez ML, Sánchez-Valverde MA, Soler M, Rodríguez MJ.The objectives of this study were to establish normal values for relative echogenicity (RE) and cross-sectional area (CSA) of the flexor tendons and ligaments of the metacarpal region of Purebred Spanish horses (PBSH), and to determine the effect of body mass index (BMI), age, sex and forelimb on these variables. Transverse ultrasonographic images were obtained using 20 normal PBSH (10 females, 10 males; 2-25 years of age; BMI 132.04-152.25; not in training). The images were digitised and values for CSA and RE were determined for each structure. The suspensory ligament was the most echogenic a...
Santschi EM.Articular injuries to the fetlock joint can be categorized as injuries to the soft tissues (synovium, ligaments, cartilage) or bone (third metacarpus/metatarsus, first phalanx, proximal sesamoids). This article focuses on the traumatic injuries to the cartilage and bone from anatomic, functional, and pathophysiological perspectives. An understanding of fetlock motion and loading will assist clinicians in the diagnosis, treatment, and, most importantly, prevention of fetlock injury in working horses.
Fortier LA, Smith RK.After tendon injury, the scar tissue that replaces the damaged tendon results in a substantial risk for reinjury. The goal of regenerative therapies is to restore normal structural architecture and biomechanical function to an injured tissue. Successful restoration processes for any tissue are thought to recapitulate those of development, in which there are spatial and temporal interactions between scaffold, growth factors, and cell populations.
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...
Sese M, Ueda H, Watanabe T, Yamamoto E, Hosaka Y, Tangkawattana P, Takehana K.The superficial digital flexor tendon (SDFT) is one of the longest tendons in the horse. In racehorses, disturbance of the locomotor functions of the SDFT occurs most frequently in the central area of the mid-metacarpal region. While many studies have investigated the equine SDFT, there are no reports to date of the morphological characteristics of collagen fibrils in the central and peripheral areas of each of the three regions that comprise the entire tendon: the myotendinous junction (MTJ), the mid-metacarpal region (mM) and the osteotendinous junction (OTJ). Mass average diameter (MAD), wh...
Owen KR, Dyson SJ, Parkin TD, Singer ER, Kristoffersen M, Mair TS.Constriction of the digital flexor tendon sheath (DFTS) and its contents by the palmar/plantar annular ligament (PAL) is well recognised. However, primary injury of the PAL has not been well documented. Objective: To describe the clinical features of PAL injury, determine its prevalence with or without subcutaneous fibrosis and/or concurrent injury within the DFTS, and assess response to treatment. Methods: Horses were selected for inclusion based upon clinical features consistent with PAL injury and the presence of a thickened PAL (> or =2 mm) verified ultrasonographically. A retrospective...
Hughes TK, Eliashar E, Smith RK.To examine the anatomic relationship of the deep branch of the lateral plantar nerve (DBLPN) with structures of the proximal metatarsal region, and to define the anatomic location of a solution injected using a single injection technique for diagnostic analgesia of the proximal suspensory ligament (PSL). Methods: Descriptive study. Methods: Cadaveric equine pelvic limbs (n=29). Methods: The proximal metatarsal region of both pelvic limbs (n=5 horses, 10 limbs) was dissected and measurements were made of anatomic structures relative to the head of the 4th metatarsal bone (HMT4). A single inject...
Butcher MT, Hermanson JW, Ducharme NG, Mitchell LM, Soderholm LV, Bertram JE.Racing and training related lesions of the forelimb superficial digital flexor tendon are a common career ending injury to racehorses but aetiology and/or predisposing causes of the injury are not completely understood. Objective: Although the injury takes place within the tendon, the lesion must be considered within the context of the function of the complete suspensory system of the distal limb, including the associated muscles. Methods: Both muscle and tendon function were investigated in vivo using implanted strain gauges in 3 Thoroughbred horses walking, trotting and cantering on a motori...
Brokken MT, Schneider RK, Sampson SN, Tucker RL, Gavin PR, Ho CP.Magnetic resonance (MR) imaging abnormalities in horses with lameness localized to the proximal metacarpal or metatarsal region have not been described. To accomplish that, the medical records of 45 horses evaluated with MR imaging that had lameness localized to either the proximal metacarpal or metatarsal region were reviewed. Abnormalities observed in the proximal suspensory ligament or the accessory ligament of the deep digital flexor tendon included abnormal high signal, enlargement, or alteration in shape. Twenty-three horses had proximal suspensory ligament desmitis (13 hindlimb, 10 fore...
Getman LM, McKnight AL, Richardson DW.The objective of this report was to provide an anatomic description of the equine palmar lateral outpouching of the middle carpal joint by comparing its arthroscopic and magnetic resonance (MR) contrast arthrography appearance and to define the structures within the palmar lateral outpouching of the middle carpal joint that can be assessed arthroscopically. MR contrast arthrography was performed on seven cadaveric limbs; images were compared with those obtained during arthroscopic exploration of the palmar lateral outpouching of the middle carpal joint. Gross dissection was performed to confir...
Vanderperren K, Raes E, Hoegaerts M, Saunders JH.The equine tarsus is the most commonly affected hindlimb region associated with lameness. Diagnostic imaging is routinely applied but because of its complexity, being composed of 10 multifaceted bones and different joints, multiple ligaments, tendons and bursae, imaging this region can be a challenge. This is the first part of a two-part review of the structures and disorders of the equine tarsus. It describes the principal disorders affecting the soft tissues of the tarsal region and addresses some of the technical aspects in taking radiographic, ultrasonographic and scintigraphic images of t...
Reed SA, Johnson SE.Mesenchymal stem cells (MSCs) offer promise as therapeutic aids in the repair of tendon, ligament, and bone damage suffered by sport horses. The objective of the study was to identify and characterize stem-like cells from newborn foal umbilical cord blood (UCB). UCB was collected and MSC isolated using human reagents. The cells exhibit a fibroblast-like morphology and express the stem cell markers Oct4, SSEA-1, Tra1-60 and Tra1-81. Culture of the cells in tissue-specific differentiation media leads to the formation of cell types characteristic of mesodermal and endodermal origins. Chondrogenic...
Dyson S, Murray R.To improve understanding of the interrelationships between injuries of the podotrochlear apparatus and deep digital flexor tendon (DDFT). Objective: There is a difference in frequency of different types of lesions at different anatomical sites of the DDFT. Lesions of the collateral sesamoidean ligament (CSL), distal sesamoidean impar ligament (DSIL), distal interphalangeal (DIP) joint and navicular bursa are seen in association with lesions of the navicular bone. Methods: The magnetic resonance (MR) images of 264 horses with unilateral or bilateral foot pain were analysed and graded. Descripti...
Sampson SN, Schneider RK, Tucker RL, Gavin PR, Zubrod CJ, Ho CP.Injury to the oblique and straight distal sesamoidean ligaments is becoming recognized as a more common cause of lameness in horses than was previously thought. The purpose of this study was to review the magnetic resonance (MR) imaging findings of 27 horses affected with desmitis of the oblique and/or straight distal sesamoidean ligament and determine long-term prognosis for horses with this diagnosis. Imaging was performed with horses in right lateral recumbency in a high-field 1 T magnet. All horses had lameness localized to the digit or metacarpophalangeal/metatarsophalangeal joint region ...
Clegg PD, Strassburg S, Smith RK.Injuries to tendons are common in both human athletes as well as in animals, such as the horse, which are used for competitive purposes. Furthermore, such injuries are also increasing in prevalence in the ageing, sedentary population. Tendon diseases often respond poorly to treatment and require lengthy periods of rehabilitation. The tendon has a unique extracellular matrix, which has developed to withstand the mechanical demands of such tensile-load bearing structures. Following injury, any repair process is inadequate and results in tissue that is distinct from original tendon tissue. There ...
Bertone AL, Goin S, Kamei SJ, Mattoon JS, Litsky AS, Weisbrode SE, Clarke RB, Plouhar PL, Kaeding CC.Xenogeneic porcine small intestinal submucosa (SIS) is a natural, biodegradable matrix that has been successfully used as a scaffold for repair of tissue defects. The goal of this study was to compare a collateral ligament transection surgically reconstructed with an anchored SIS ligament to a sham-operated control procedure for the correction of joint laxity using an equine model. Ten metacarpophalangeal joints from 10 horses had complete transection of the lateral collateral ligament. In 6 horses, the collateral ligament was reconstructed with a multilaminate strip of SIS anchored with screw...
Bolen G, Busoni V, Jacqmot O, Snaps F.Although ultrasonography is widely used in equine orthopedics, its use in the distal portion of the digit is still limited. The purpose of this descriptive study was to document the normal ultrasonographic appearance of the palmarodistal aspect of the digital area imaged between the bulbs of the heels. Ultrasonographic images were obtained with a 7.5 MHz microconvex transducer in 10 fresh equine cadaver forelimbs and five soundhorses. Sagittal, parasagittal, and transverse images were obtained from the proximal aspect of the middle phalanx to the distal sesamoid bone. Anatomic sections were ob...
Murray RC, Dyson SJ, Tranquille C, Adams V.Although anecdotal reports of increased orthopaedic injury risk in equine sports exist, there is little scientific evidence to support this. Objective: To test whether horses undertaking a single competitive sport have increased risk of specific injuries compared to those used for general purpose riding (GP); and whether injury type varies with sport category and performance level. Methods: Data from 1069 records of horses undergoing orthopaedic evaluation (1998-2003) and meeting inclusion criteria were reviewed. Sport category (GP, showjumping, dressage, eventing, racing), level (nonelite or ...
Goff LM, Jasiewicz J, Jeffcott LB, Condie P, McGowan TW, McGowan CM.Sacroiliac disease (SID) is an important cause of loss of performance in horses, yet little is known about the biomechanics of movement of the sacroiliac joint (SIJ). Objective: (a) To document the presence of equine SIJ motion by measuring the change in cross-sectional area (CSA) of the dorsal portion of the dorsal sacroiliac ligament (DSIL) during application of manual forces to the pelvis, and to ascertain if this varied between horses with SID and normal horses; (b) To determine the amount and direction of motion available at the equine SIJ using 3-D orientation sensors, and how motion is ...
Spriet M, Mai W, McKnight A.Increased signal intensity in one of the collateral ligaments of the distal interphalangeal (DIP) joint of sound horses in images acquired using a low-field magnet with vertical orientation of the magnetic field was investigated as a possible manifestation of the magic angle effect. Three isolated equine digits were imaged using the following pulse sequences: (1) spin echo TI, (2) turbo spin echo proton density and T2, and (3) 3D gradient echo T1, in different positions by mildly changing the orientation of the long axis of the digit, in the dorsal plane, relative to the magnetic field. The si...
Henson FM, Lamas L, Knezevic S, Jeffcott LB.Injury to the supraspinous ligament (SSL) is reported to cause back pain in the horse. The diagnosis is based on clinical examination and confirmed by ultrasonographic examination. The ultrasonographic appearance of the supraspinous ligament has been well described, but there are few studies that correlate ultrasonographic findings with clinical pain and/or pathology. This preliminary study aims to test the hypothesis that unridden horses (n = 13) have a significantly reduced frequency of occurrence of ultrasonographic changes of the SSL consistent with a diagnosis of desmitis when compared to...
Gupte CM, Bull AM, Murray R, Amis AA.The purpose of this study was to investigate the presence, position and relative sizes of the meniscofemoral ligaments (MFL) in three quadrupeds and humans and relate these to the caudal slope of the lateral tibial plateau. Canine, ovine and equine stifles and human knees were dissected to identify the presence of MFLs, their obliquity in relation to the caudal cruciate ligaments (CCL), the relative size and shape of the MFLs compared with the CCL, the points of femoral attachment of the MFLs and CCL, and the distance between the MFLs and CCL at their midpoints. The lateral tibial condyle was ...
Lawson SE, Chateau H, Pourcelot P, Denoix JM, Crevier-Denoix N.As equine musculoskeletal models become common, it is important to determine their sensitivity to the simplifications used. A subject-specific distal forelimb model was created using bones extracted from CT scans to examine movement from in-vivo invasive-marker motion capture. The movements of the sesamoid bones were simulated using the constraints of maintaining an isometric virtual ligament and maintaining contact between the appropriate articular surfaces, creating a variable moment arm for the tendons. The simulation of the proximal sesamoid bones was compared to movement recorded in-vitro...
Puchalski SM, Galuppo LD, Hornof WJ, Wisner ER.A technique for regional delivery of contrast medium to the foot of the horse to increase the diagnostic utility of computed tomography (CT) for the characterization of soft tissue structures within the hoof capsule was developed. An intraarterial catheter was placed under ultrasound guidance into the medial palmar artery at the level of the carpus to facilitate a steady-state infusion of iodinated contrast medium. Two 5 mm collimated contiguous acquisition CT scans were performed in 10 horses without lameness or radiographic evidence of distal sesamoid bone degeneration. CT examination was pe...
Zarucco L, Wisner ER, Swanstrom MD, Stover SM.Biomechanical models that compute the lengths and forces of muscle-tendon units are broadly applicable to the study of factors that promote injury and the planning and effects of orthopedic surgical procedures in equine athletes. A three-dimensional (3D) generic musculoskeletal model of the equine forelimb comprised of bony segment, muscle-tendon, and ligament information, was developed based on high-resolution computed tomographic (CT) and T1-weighted magnetic resonance (MR) images from an isolated forelimb of a Thoroughbred racehorse. Image fusion was achieved through coregistration of CT an...
Sese M, Ueda H, Watanabe T, Yamamoto E, Hosaka Y, Tangkawattana P, Takehana K.The superficial digital flexor tendon (SDFT) is one of the longest tendons in the horse. In racehorses, disturbance of the locomotor functions of the SDFT occurs most frequently in the central area of the mid-metacarpal region. While many studies have investigated the equine SDFT, there are no reports to date of the morphological characteristics of collagen fibrils in the central and peripheral areas of each of the three regions that comprise the entire tendon: the myotendinous junction (MTJ), the mid-metacarpal region (mM) and the osteotendinous junction (OTJ). Mass average diameter (MAD), wh...
Taintor J, Caldwell F, Almond G.A mare was evaluated for acute left forelimb lameness with effusion of the carpal flexor sheath. No osseous abnormalities were noted during radiographic examination. Significant disruption of the accessory ligament of the deep digital flexor tendon was seen during ultrasonographic examination. Carpal sheath effusion and lameness resolved after medical treatment. Une jument a été évaluée pour une boiterie aiguë de la patte avant gauche avec effusion de la gaine du fléchisseur carpien. Aucune anomalie osseuse n’a été observée durant l’examen radiographique. Une perturbation importa...
Gallastegui A.Over the past 5 years, advancements in diagnostic imaging technology have led to improvement of radiographic technique and development of standing computed tomography (CT) and PET-CT scanners. Although these modalities are in their initial stages of development and clinical applications, they are meant to revolutionize the diagnosis and management of diseases of the foot in the standing patient, in particular detecting subclinical lesions, and the establishment of computer-assisted surgical suits. This article also reviews the improved radiographic projections of the equine foot and benefits ...
Whitton RC, Rose RJ.To determine the relative contributions of the palmar intercarpal ligaments in the midcarpal joint to the restraint of dorsal displacement of the proximal row of carpal bones. Methods: A biomechanical study of cadaver equine carpi. Methods: Eight equine forelimbs from six thoroughbred horses. Methods: With joints in full extension, the radius was dorsally displaced while midcarpal joint displacement was measured. The restraining force at a joint displacement of 1.5 mm was determined from the load-displacement curve. A ligament or pair of ligaments was then cut and the testing procedure repeate...
Secchi V, Masala G, Corda A, Corda F, Potop E, Barbero Fernandez A, Pinna Parpaglia ML, Sanna Passino E.Early diagnosis of tendon injuries and accurate long-term monitoring of the healing process are key for equine veterinarians that use conventional ultrasonography. The development of strain elastography could improve the management of clinical cases. The aim of the study was to assess the intraobserver repeatability and interobserver reproducibility of manual measurements of the colored areas of the tendons within elastograms and to standardize this manual modality by comparing the analysis of the images with ImageJ. Twenty elastograms of the injured superficial digital flexor tendons (SDFTs) ...
Nazem MN, Sajjadian SM.Palmar region of metacarpus in the horses and donkeys is an important region because of its tendons and ligaments which contribute to stay apparatus. This study was done on forelimbs of 6 healthy Miniature donkeys to detect the tendons, ligaments and their accessories on the palmar surface of metacarpus in this animal. Methods: Based on that magnetic resonance imaging (MRI) is a good technique to evaluate the soft tissues such as tendons and ligaments, palmar aspects of metacarpus in 6 euthanatised Miniature donkeys were prepared for anatomical and trans-sectional MRI studies to determine the ...
Klohnen A, Wilson DG.Nonstrangulating indirect scrotal hernias were corrected in two 4-week-old Percheron foals by a laparoscopic technique. After laparoscopic reduction of herniated nonstrangulated small intestine each testes was retracted through the vaginal ring. The ligament of the tail of the epididymis was transected by electrocautery. The testicular vessels and nerves were isolated by cautery of the mesenteric portion of the mesorchium and then ligated. Staples were used to close the opening of the inguinal canal by apposing the peritoneal edges of the vaginal ring. Resection of umbilical stalk remnants via...
Stick JA, Nickels FA, Williams MA.Desmotomy of the accessory ligament of the deep digital flexor muscle (inferior check desmotomy) permitted Standardbred foals affected with flexural deformities to reach their full athletic potential. Long-term effects of inferior check desmotomy were examined in 23 Standardbreds over a 10-year period. Six of 11 foals that were treated surgically either raced 6 times and obtained a race record or were training sound (if yearlings). All 12 horses with flexural deformity that did not receive an inferior check desmotomy had an unfavorable outcome (no race record). Foals that had surgery performed...
Lamb L, Zubrod C, Hague B, Brakenhoff J, Major M.The significance of collateral ligament desmitis of the tarsocrural joint is often clinically underestimated, because it is an uncommon injury with a guarded prognosis for athletic soundness. The objective of this study was to describe the clinical presentation, treatment, and outcome of 12 horses with collateral ligament desmitis, along with tarsocrural joint synovitis secondary to hemarthrosis. Criteria for inclusion in this study included clinical signs of tarsocrural joint synovitis and sonographic evidence of collateral ligament desmitis. This retrospective study evaluated horses over an ...
Hawkins JF, Schumacher JS, McClure SR, Light GS.Small intestinal incarceration through the lateral ligament of the urinary bladder was diagnosed in a 14-year-old, 569-kg, castrated Quarter Horse. The incarceration was corrected by ventral midline celiotomy. Approximately 70 cm of the middle portion of the jejunum was resected and end-to-end, single-layer anastomosis was performed. After surgery, the horse developed signs of adynamic ileus and lameness in the right forelimb. The horse developed laminitis in all 4 feet within 24 hours of surgery. The horse was euthanatized because of poor prognosis for survival. At necropsy, a 4.5-cm rent was...
Milner PI, Dimmock O, Barnes K.Neurovascular variation may be relevant when performing surgical techniques to the proximal plantar metatarsal region. Objective: To document variations in the neurovascular anatomy of the proximal plantar metatarsal region and study the relationship of the neurovascular components to each other and other structures located in this area. Methods: Descriptive anatomical study. Methods: Paired cadaver hind limbs from 15 horses were dissected from the distal tibia to the metatarsophalangeal joint. Deep branch of the lateral plantar nerve (DBLPN) length, location of its origin from the lateral pla...
Eliashar E, Dysont SJ, Archer RM, Singer ER, Smith RK.Desmopathy of the accessory ligament of the deep digital flexor tendon (ALDDFT) in the hindlimb is an unusual cause of lameness in horses, and reports of the condition are sparse. Objective: To describe the clinical and ultrasonographic findings, therapy and outcome of 23 horses treated for desmopathy of the ALDDFT in the hindlimb. Methods: Records of 23 horses with ultrasonographic evidence of desmopathy of the ALDDFT in one or both hindlimbs from 3 referral centres were reviewed retrospectively. Age, breed, sex, duration and nature of clinical signs, results of clinical and lameness examinat...
Colborne GR, Heaps LA, Franklin SH.Joint congruity and ligaments restrain the distal limb joints from excessive motion in the transverse and frontal planes, but the magnitudes and direction of the horizontal twisting moments around the hoof's centre of pressure (CoP) that induce these motions are unknown. Objective: To quantify the horizontal moment around the vertical axis through the hoof's CoP at walk, and to determine whether these are symmetric. Methods: Nine sound Thoroughbred horses (mean age 53 years; mean mass 502 kg) were led at walk in a straight line across a Kistler force platform. Five trials were collected for ea...
Depuydt E, Chiers K, Van Hecke L, Saunders J, Martens A, Pille F, Spaas JH.Injuries to equine tendons and ligaments are career-compromising, causing reduced performance and premature retirement. Promising treatment alternatives have been investigated in the field of mesenchymal stem cells (MSCs). In this study, the tissue adherence and protein expression of tenogenic primed mesenchymal stem cells (tpMSCs) after administration to ex vivo tendon and ligament explants is investigated. First, collagen type I (COL I) and smooth muscle actin (SMA) expression was assessed in cytospins prepared from native MSCs and tpMSCs. Second, equine superficial digital flexor tendon and...
McGhee JD, White NA, Goodrich LR.To determine clinical and ultrasonographic abnormalities in horses with primary desmitis of the palmar or plantar annular ligament (PAL) and the response to treatment. Methods: Retrospective study. Methods: 25 horses. Methods: Data collected from medical records included signalment, horse use, affected limb, severity and duration of lameness, results of diagnostic tests performed, ultrasonographic findings, treatment, and outcome. Results: All horses had a prominent swelling in the region of the affected PAL, and signs of pain were evident during palpation of the swelling. In all horses, the a...
Smith MA, Dyson SJ, Murray RC.Collagen fibers oriented at 55 degrees to the static magnetic field (B0) are characterized by an artifactual increase in signal intensity due to the magic angle effect. We hypothesized that there would be increased signal intensity in the collateral ligaments of the distal interphalangeal joint and oblique sesamoidean ligaments when these ligaments were at angles approaching 55 degrees to a horizontal B0 during standing magnetic resonance (MR) imaging. MR imaging was performed on four cadaver forelimbs in a 0.27 T standing system. Transverse and dorsal images were obtained using various sequen...
Selberg K, Werpy N.Ungual cartilage ossification in the forelimb is a common finding in horses. Subtle abnormalities associated with the ungual cartilages can be difficult to identify on radiographs. Magnetic resonance (MR) imaging findings of 22 horses (23 forelimbs) with a fracture of the distal phalanx and ossified ungual cartilage were characterized and graded. All horses had a forelimb fracture. Eleven involved a left forelimb (seven medial; four lateral), and 12 involved a right forelimb (five medial; seven lateral). All fractures were nonarticular, simple in configuration, and nondisplaced. The fractures ...
Carpenter EM, Hendrickson DA, James S, Franke C, Frisbie D, Trostle S, Wilson D.To determine a hand-tied ligature knot configuration, suture size, and suture type that would be an acceptable substitute to commercially available ligature knots for use in equine laparoscopic surgery. Methods: Three-factor ANOVA with the fixed effects being suture type, suture size, and knot type. The dependent variable was ligature security (load to failure). Methods: Commercially available Endoloop and 4 hand-tied slipknot ligatures were compared with a 4-layer square knot. The hand tied ligature knots tested were the 4S modified Roeder knot, the Brooks knot, the modified Roeder knot, and ...
Boero MJ, Kneller SK, Baker GJ, Metcalf MR, Twardock AR.Injury of the lateral collateral ligaments of the tarsocrural joints was diagnosed in nine Standardbred pacers. The average age was 4.9 years. The severity of the lameness varied from severe to subtle and joint effusion was seen in eight of 10 tarsocrural joints. A positive hindlimb flexion test was seen in four of six cases in which results were recorded. The identification of the site of involvement was based on a focal intense 'hot spot' seen on scintigraphy, and new bone formation seen radiographically at the anatomical sites of insertion of the long lateral collateral ligament of the tars...
José Antonio G, Jim S, Ramés SJ, Rohrbach BW, Alejandro Rodríguez M, Laura Romero R, Robert D.To examine changes occurring in normal pelvic suspensory ligaments (SLs) of horses after denervating these ligaments and to investigate the effect chronic inflammation might have on these changes. Methods: 10 horses. Methods: The SL of 1 randomly selected pelvic limb of each of 5 horses was injected with collagenase to induce desmitis, and 42 days later, the proximal aspect of both pelvic SLs were denervated. The SLs were harvested 120 days after being denervated, and the morphological and histological characteristics of each collagenase-injected, denervated SL were compared with those of the ...
Lopez-Navarro G, Trigo-Tavera FJ, Rodriguez-Monterde A, Gutierrez-Ospina G, Arechavaleta-Velasco M, Schumacher J, Schumacher J.Proximal suspensory desmitis (PSD) is a common cause of lameness in the pelvic limb, but could also affect the thoracic limb of competing and non-competing horses. Most horses diagnosed with PSD in a thoracic limb respond to rest followed by controlled exercise, but in a small percentage of affected horses, lameness persists. In one study, four horses chronically lame because of PSD in a thoracic limb became sound after neurectomy of the deep branch of the lateral palmar nerve (DBLPaN), which innervates the proximal aspect of the suspensory ligament (SL; Guasco et al., 2013). Whether neurectom...
Rabba S, Petrucci V, Petrizzi L, Giommi DW, Busoni V.Information concerning B-mode ultrasonographic abnormalities and power Doppler (PD) signal in suspensory ligament branches of nonlame working Quarter Horses are not reported. The aims of this study were to investigate the prevalence of B-mode ultrasonographic abnormalities and PD signal in suspensory ligament branches in a group of nonlame working Quarter Horses and to compare B-mode findings with PD findings of horses in two different training (barrel racing and team roping). Twenty-one Quarter Horses in training, 14 barrel racing (Group B) and seven team roping horses (Group R), were assesse...
Ingle-Fehr JE, Baxter GM.To describe endoscopic approaches to the calcaneal bursa and clinical findings in 2 horses with calcaneal bursitis. Methods: Cadaver evaluations and retrospective case reports. Methods: 12 cadavers and 2 adult horses. Methods: Cadaver specimens of the calcaneal bursa were evaluated with a rigid arthroscope and gross dissection to determine the endoscopic appearance of anatomic structures located within the bursa. The site(s) for placement of the arthroscope and instrument(s) was determined based on cadaver dissection and endoscopic examination. Results: Placement of the arthroscope 1 cm dorsal...
Zellmann P, Ribitsch I, Handschuh S, Peham C.We developed a finite element model (FEM) of the equine stifle joint to identify pressure peaks and simulate translocation and deformation of the menisci. A series of sectional magnetic resonance images (1.5 T) of the stifle joint of a 23 year old Shetland pony gelding served as basis for image segmentation. Based on the 3D polygon models of femur, tibia, articular cartilages, menisci, collateral ligaments and the meniscotibial ligaments, an FEM model was generated. Tissue material properties were assigned based on data from human (Open knee(s) project) and bovine femoro-tibial joint available...
Le Roux C, Carstens A.Axial sesamoiditis or osteitis of the proximal sesamoid bones (PSBs) in the horse is described as a rare condition. The cause remains unknown and speculative, with vascular, infectious, and traumatic aetiologies implicated. It is specifically associated with injury of the palmar or plantar ligament (PL), also known as the intersesamoidean ligament. Imaging findings are generally rewarding and radiological changes are typical, if not pathognomonic, for the condition. Lesions consist of bone lysis at the apical to mid-body axial margins of the PSBs, with variable degrees of joint effusion. Radio...
Roach JM, Pfau T, Bryars J, Unt V, Channon SB, Weller R.Kinematic evaluation of the distal limb of the horse using standard methods is challenging, mainly due to the hoof capsule restricting visualisation, but the recent development of a high-speed fluoroscopy (HSF) system has allowed in vivo cineradiographic assessment of moving skeletal structures at high speeds. The application of this non-invasive method to the equine distal limb is used to describe 'internal' distal limb kinematics including intra-horse and inter-horse variability, and variability between walk and trot. Distal limb kinematic data were collected at walk and trot from six non-la...
May-Davis S, Brown W, Vermeulen Z.Conflicting data predominantly describes the equine nuchal ligament lamellae (NLL) attachments as C2-C6 or C2-C7; however, preliminary evidence suggests C2-C5. This study aimed to identify morphological variations in the attachments of the NLL in four species of the family equidae and determine if the variations were species or breed linked. Cadaveric examination evaluated 98 equids; Equusasinus (n = 2), Equus ferus caballus (n = 93), Equus przewalskii (n = 2), and Equus quagga boehmi (n = 1). Twenty breeds of E. f. caballus were included according to breed type-modern horse (n = 81), anc...
Werpy N, Chapman K, Griffith L.When evaluating suspensory ligament branch splits, there is a discrepancy between high field MRI findings and weight bearing ultrasonographic imaging characteristics. In this descriptive and retrospective case series, ultrasonographic examination was performed on suspensory ligament branches with the limbs in weight bearing and non-weight bearing positions. Suspensory ligament branch splits were defined as linear regions of decreased echogenicity when imaged with the limb in a weight bearing position that increased in size and became anechoic with the limb in a non-weight bearing position. Thi...
Talbot AM, Rodrigues M, Maddox TW.Mineralisation of the longitudinal odontoid ligament has recently been identified in three horses undergoing computed tomographic (CT) examination, but published studies describing the clinical relevance of this finding are currently lacking. The objective of this retrospective, analytical, cross-sectional study was to investigate the relationship of this image finding to primary presenting complaint, age, breed, use and sex of the patient, and determine any association to the clinical signs of head shaking, neck pain or restricted range of neck motion. Computed tomographic images of 96 horses...
Hontoir F, Paques F, Simon V, Balau B, Nicaise C, Clegg P, Dugdale A, Vandeweerd JM.Foot pain is a frequent cause of lameness in horses and can involve multiple structures within the hoof. The T-ligament (an anatomical structure connecting the synovium of the distal interphalangeal joint, the digital flexor tendon sheath and the navicular bursa) is poorly described. Five pairs of equine cadaver distal forelimbs were collected from a slaughterhouse. Sagittal sections (medial, middle and lateral) were obtained and processed with Haematoxylin Eosin Safran, Unna's Orcein, and Picrosirius red stains. Histological assessment revealed that the T-ligament was covered by the surroundi...
