Topic:Ligaments
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.
Spinal ligament pathology. Young elite athletes, particularly horses used for jumping, are at a relatively high risk for injury to the ligaments associated with the axial skeleton. Extreme back flexion appears to be a contributing factor to ligament damage. Back pain due to injury of the ligaments of the axial skeleton has often been considered to be secondary to lower limb injury, to the extent that a separate definitive diagnosis, treatment, and prognosis were unnecessary. Diagnostic imaging, ultrasound in particular, has demonstrated ligamentous damage that can be the limiting factor in return to previous athletic us...
Desmotomy of the accessory ligament of the superficial digital flexor tendon in the horse with use of a tenoscopic approach to the carpal sheath. To describe a tenoscopic approach to the carpal sheath for desmotomy of the accessory ligament of the superficial digital flexor tendon. Methods: The surgical procedure was developed with use of normal forelimbs from equine cadavers and experimental horses. Methods: Twelve equine cadaveric forelimbs, 4 forelimbs from 2 horses anesthetized for terminal surgical laboratories, and 10 forelimbs from five experimental horses were used. Methods: The limbs were positioned lateral side up with the carpus slightly flexed. After distention of the carpal sheath, a portal was made approximately 2 cm proxi...
Histopathological findings in the medial palmar and dorsomedial intercarpal ligaments of the equine midcarpal joint. Medial palmar intercarpal ligaments (MPICL) and dorsomedial intercarpal ligaments (DMICL) from the midcarpal joints of 11 adult horses in training were examined histopathologically. These were compared with ligaments from seven horses less than 12 months of age, and 10 grossly enlarged DMICLs of adult horses. Tearing of the MPICL was observed in 15 of 22 joints from adult horses. Collagen fibre bundles of the MPICLs generally were disorganized and poorly aligned, and there were large areas of loose connective tissue. In young horses there was more parallel alignment of collagen bundles and les...
In vitro attenuation of impact shock in equine digits. This study was designed to test the impact characteristics of the equine digit in vitro with the objective of providing a better understanding of the role of the digital structures in the attenuation of impact shock. Uni-axial accelerometers were mounted on cadaver digits on the distolateral hoof wall, the proximolateral hoof wall, the dorsal surface of the second phalanx, and the mid-lateral first phalanx. The hoof-mounted accelerometers were aligned with the hoof tubules while the bone-mounted accelerometers were oriented along the longitudinal axis of the bone. Each digit was mounted in a t...
Incarceration of the small colon through a rent in the gastrosplenic ligament in a pony. A 10-year-old castrated male pony was examined for intermittent signs of abdominal pain of 3 days' duration. An incarceration of the small colon through a rent in the gastrosplenic ligament was found. Resection and end-to-end anastomosis were performed on the affected portion of the small colon. The pony recovered and returned to its previous degree of activity. Incarceration of the small intestine and large colon through rents in the gastrosplenic ligament are documented, although involvement of the small intestine is more common. To the best of our knowledge, incarceration of the small colon...
Instability-induced osteoarthritis in the metacarpophalangeal joint of horses. To establish an instability model of osteoarthritis (OA) that mimics the early changes of naturally acquired OA. Methods: 6 mature radiographically normal horses. Procedure-The collateral and lateral collateral sesamoidean ligaments were transected in a metacarpophalangeal (MCP) joint in each horse. Lameness examinations were performed every 7 days after surgery for 8 weeks. Radiographs were taken immediately before and after desmotomy and 8 weeks after surgery. Eight weeks after surgery, bilateral MCP joints were grossly evaluated, specimens of articular cartilage were harvested for histologi...
Endoscopy of the calcaneal bursa in horses. 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...
Innervation of the equine mature and immature proximal sesamoid bone by calcitonin gene-related peptide and substance P-containing nerves. To localize and determine relative frequency of occurrence of calcitonin gene-related peptide (CGRP) and substance P (SP) fibers in the proximal sesamoid bones (PSB) and adjacent structures in sound horses. Methods: 4 foals and 3 adult horses. Methods: Medial PSB and adjacent ligaments of both forelimbs were collected, flushed, and fixed in buffered 4% formalin. The left PSB were cut into 5 longitudinal, sagittally oriented slabs, and the right PSB were cut into 5 transverse slabs. After decalcification in EDTA, slices were transferred to a 30% sucrose solution, deep frozen, sectioned (80 micr...
Muscle-tendon stresses and elastic energy storage during locomotion in the horse. The stresses acting in muscle-tendon units and ligaments of the forelimb and hindlimb of horses were determined over a range of speed and gait based on recordings of ground reaction forces and limb kinematics. Maximum stresses of 40-50 MPa were calculated to act in several of the principal forelimb (superficial digital flexor (SDF), deep digital flexor (DDF), ulnaris lateralis (UL) and flexor carpi ulnaris/radialis (FCU/R)) and hindlimb tendons (plantaris, DDF) at the fastest galloping speeds recorded (up to 7.4 m s-1). Smaller stresses were found for the gastrocnemius (GAST) tendon (30 MPa) a...
Mechanical properties of the tendinous equine interosseus muscle are affected by in vivo transducer implantation. Liquid metal strain gauges (LMSGs) were implanted in the tendinous interosseous muscle, also called suspensory ligament (SL), in the forelimbs of 6 ponies in order to quantify in vivo strains and forces. Kinematics and ground reaction forces were recorded simultaneously with LMSG signals at the walk and the trot prior to implantation, and 3 and 4 days thereafter. The ponies were euthanised and tensile and failure tests were performed on the instrumented tendons and on the tendons of the contra lateral limb, which were instrumented post mortem. The origo-insertional (OI) strain of the SL was co...
Low-field magnetic resonance imaging (0.2 T) of tendons with sonographic and histologic correlation. Cadaveric study. The authors evaluate the role of low-field strength magnetic resonance imaging (MRI) compared with sonography in the evaluation of degenerative changes of tendons, with histologic correlation, based on investigations of horse cadavers. Methods: Low-field MRI and sonography was performed in 42 hours specimens for the evaluation of tendons and ligaments. Magnetic resonance imaging included sagittal and axial T1-weighted, T2-weighted, and gradient echo images. Sonography and MR images were evaluated for degenerative changes or tears and the findings were correlated with the histologic results. Re...
Stress/strain behaviour of the equine laminar junction. The equine laminar junction plays a vital role in transferring the forces of weight-bearing between the epidermal hoof wall and the bone of the third phalanx, but the way in which it performs this function is poorly understood. Using samples from sites varying proximodistally and circumferentially around the hoof, the stress/strain behaviour of this tissue was characterised in three directions: radial tension and proximodistal and mediolateral shear. The influences of toe angle and length were also examined. For all three test directions, the modulus of elasticity increased with increasing str...
Tenoscopic anatomy of the equine carpal flexor synovial sheath. To describe the tenoscopic anatomy of the carpal sheath of the flexor tendons (carpal sheath) viewed from a lateral approach. Methods: Tenoscopic observation of structures within the carpal sheath subsequently confirmed by dissection. Methods: 12 equine cadaveric forelimbs. Methods: The limbs were positioned lateral side up with the carpus slightly flexed. After distention of the carpal sheath, a portal for the arthroscope was made approximately 3 cm proximal to the distal radial physis and 2.5 cm caudal to the radius between the tendons of the ulnaris lateralis and lateral digital extensor mu...
Effects of experimental desmotomy on material properties and histomorphologic and ultrasonographic features of the accessory ligament of the deep digital flexor tendon in clinically normal horses. To evaluate posttrauma biomechanical behavior of the scar attributable to desmotomy of the accessory ligament of the deep digital flexor tendon (AL-DDFT), compared with the histomorphologic and ultrasonographic appearance. Methods: 5 Standardbred trotters. Methods: Gross appearance, length, cross-sectional area (CSA), in vitro material properties, and ultrasonographic and histomorphologic features were studied 6 months after desmotomy. Tensile tests were conducted, with forces and elongation simultaneously recorded. Surgically treated limbs were compared with nontreated contralateral limbs. Re...
Long-term consequences of experimental desmotomy of the accessory ligament of the deep digital flexor tendon in adult horses. To evaluate clinical and biomechanical consequences of desmotomy of the accessory ligament (AL) of the deep digital flexor tendon (DDFT) of equine forelimbs and determine whether this procedure is a viable treatment for chronic desmitis of the AL-DDFT. Methods: 6 adult Standardbred trotters. Methods: Biomechanical recordings obtained before and 6 months after desmotomy were compared. Walk and trot joint angles, ground reaction forces, peak joint moments, and tendon forces were assessed. Results: Within 10 days after surgery, all horses were sound at a trot. Swelling, increased carpal flexion i...
The distribution of cartilage oligomeric matrix protein (COMP) in tendon and its variation with tendon site, age and load. A protein prominent in guanidine hydrochloride extracts of adult bovine and equine digital flexor tendons was confirmed to be Cartilage Oligomeric Matrix Protein (COMP) by non-reducing and reducing SDS-PAGE, reaction with rabbit anti-COMP polyclonal antiserum on Western blots, trypsin digestion followed by HPLC on a C2/C18 column, and identification of COMP mRNA from tendon on Northern blots. Immunohistochemistry and Western blots of extracts showed COMP to be present in all regions of digital flexor tendons. Equine tendon COMP was purified by ion exchange chromatography and gel filtration and...
Gross and ultrasonographic anatomy of the carpal flexor tendon sheath in horses. This study was undertaken to establish the gross anatomy and the ultrasonographic appearance of the carpal digital flexor tendon sheath (carpal sheath) and the palmar carpal region in normal horses. The isolated forelimbs from 15 horses were used to study the morphology of the sheath and associated structures, including a detailed study of the location of the main blood vessels and nerves in that region. These limbs and the forelimbs of five live, sound horses were also examined ultrasonographically. The examination yielded good soft tissue detail of the tendons and ligaments, synovial and per...
Postmortem lesions in the intercarpal ligaments of the equine midcarpal joint. To determine the frequency of damage to the medial palmar intercarpal ligament (MPICL), and the range of sizes of the dorsomedial intercarpal ligament (DMICL) of the midcarpal joint in horses with no history of carpal joint disease. Methods: Cadaver limbs were collected from 72 horses with no history of carpal joint disease. One hundred and forty-two midcarpal joints were dissected and the MPICL and DMICL were examined. Measurements were made with a digital micrometer. Results: MPICL tearing was present in 88 of 96 joints from horses 2 years and older. Tears were predominantly of the dorsolate...
Desmotomy for treatment of chronic desmitis of the accessory ligament of the deep digital flexor tendon in a horse. Chronic lameness was determined to be caused by desmitis of the accessory ligament of the deep digital flexor tendon and adhesions associated with these 2 structures. Desmotomy of the accessory ligament, resection of adhesions, and controlled exercise during convalescence resulted in return to normal use without apparent lameness.
The intercarpal ligaments of the equine midcarpal joint, Part 3: Clinical observations in 32 racing horses with midcarpal joint disease. To characterize the clinical features of intercarpal ligament pathology and to determine the relationship among palmar intercarpal ligament tearing, dorsomedial intercarpal ligament (DMICL) hypertrophy, and other intraarticular lesions. Methods: Prospective clinical observations. Methods: Twenty-eight thoroughbred and four standardbred race horses. Methods: Clinical, radiographic, and arthroscopic examination of 53 midcarpal joints of 32 horses. Results: Palmar intercarpal ligament tearing was observed in 30 joints of 22 horses. Some tearing of the medial palmar intercarpal ligament (MPICL) wa...
The intercarpal ligaments of the equine midcarpal joint, Part 2: The role of the palmar intercarpal ligaments in the restraint of dorsal displacement of the proximal row of carpal bones. 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...
The intercarpal ligaments of the equine midcarpal joint, Part 1: The anatomy of the palmar and dorsomedial intercarpal ligaments of the midcarpal joint. To describe in detail the structure of the medial palmar intercarpal ligament (MPICL), the lateral palmar intercarpal ligament (LPICL), and a dorsomedial intercarpal ligament (DMICL) of the equine midcarpal joint. Methods: Dissections of equine midcarpal joints. ANIMALS AND SAMPLE POPULATION: Ten carpal joints from eight thoroughbred horses. Methods: Detailed dissections of the midcarpal joint were performed, with particular attention paid to the MPICL, the LPICL, and the DMICL. The attachments and dimensions of these structures were recorded, as well as their behavior during joint movement. R...
[Scanning electron microscopic investigations on the anatomy of the fetlock joint in horses]. Striking synovial structures were taken and their surface was investigated by scanning electron microscopy. Depending where the probes were taken from, the stratum synovial was arranged in a different way. The synovial intima seems to miss under the tendon of the long/commune extensor muscle, the collateral ligaments and the sesamoidean collateral ligaments. That is why the subsynovial tissue forms the superficial layer. The surface of the probes taken sidewards to the tendon of the extensor muscle and of the synovial fold, which is situated between the metacarpus/metatarsus and the proximal p...
Repair of a deep digital tendon deficit in a horse using a polypropylene implant. A yearling horse was treated for a chronic wound with a 4 cm deficit in the deep digital tendon. The gap in the tendon was bridged with paired polypropylene braided implants designed for use as a ligament augmentation device. Uncomplicated healing and return to function occurred.
Mechanical properties of pathological equine superficial digital flexor tendons. The objective of this study was to mechanically characterise superficial digital flexor tendon (SDFT) lesions. Eight pathological SDFTs, isolated from 6 adult horses, were tested in traction until rupture (at 1 mm/s). The stresses and strains simultaneously undergone by each of the 7 segments of a tendon were determined throughout the test, and the modulus of elasticity of each segment was evaluated from the segmental stress-strain curve thus obtained. These mechanical data were compared to those obtained on 10 normal SDFTs. After the test, the tendinous segments were submitted to a histologic...
[Anatomy of the fetlock joint in horses by means of joint casts]. The equine fetlock joint cavity shows ten pouches. The dorsal recess, which is oriented to the proximal side, is separated from those three pouches, which show to the distal direction, by several capsular folds. These folds are documented by means of sagittal sections through the fetlock joint. A medial/lateral recess is covered by the deep part of the collateral ligament of the fetlock joint. The collateral ligaments as well as the sesamoidean collateral ligaments are closely connected with the joint capsule, from which two capsular folds are separated. Between the part of the sesamoidean col...
Ultrasonographic examination of the proximal scutum in the horse. Normal and abnormal ultrasonographic images are presented of the proximal scutum (proximal sesamoid bones and palmar ligament) in the horse. Comparison between anatomical sections, MRI (magnetic resonance imaging) and ultrasound scans enabled the authors to establish the normal ultrasonographic anatomy of the palmar fetlock. Nine cases of proximal scutum injuries were identified ultrasonographically, of which 4 are illustrated. On normal limbs, the facies flexoria of the proximal sesamoid bones appeared as a thin and regular hyperechoic line and the palmar ligament was regularly echogenic. Les...