Topic:Deep Digital Flexor Tendon
The Deep Digital Flexor Tendon (DDFT) is a critical structure in the equine limb, extending from the muscles in the upper leg down to the coffin bone in the hoof. It is responsible for flexing the lower limb and plays a significant role in the horse's movement and weight-bearing capabilities. The DDFT runs behind the cannon bone and passes over the navicular bone before attaching to the pedal bone. Injuries to the DDFT can occur due to overuse, trauma, or degenerative changes, often leading to lameness and requiring careful management. This page compiles peer-reviewed research studies and scholarly articles that explore the anatomy, function, injury mechanisms, and treatment options related to the Deep Digital Flexor Tendon in horses.
Medical treatment of horses with deep digital flexor tendon injuries diagnosed with high-field-strength magnetic resonance imaging: 118 cases (2000-2010). To describe the location and severity of deep digital flexor tendon (DDFT) lesions diagnosed by means of high-field-strength MRI in horses and to identify variables associated with return to activity following medical treatment. Methods: Retrospective case series. Methods: 118 horses. Methods: Medical records of horses with DDFT injury diagnosed with MRI over a 10-year period (2000-2010) and treated medically (intrasynovial administration of corticosteroids and sodium hyaluronan, rest and rehabilitation, or both) were reviewed. History, signalment, use, results of lameness examination and diag...
Ex-Vivo Evaluation of a Modified Teno Fix(®) Device Repair Pattern Versus a 3-Loop Pulley for Repair of Equine Flexor Tendons. To compare the load to ultimate failure, load to a 2 mm gap, mode of failure, and gap at failure (mm) of the Teno Fix(®) (TF) to the 3-loop pulley (3LP) for repair of equine tendon lacerations. The use of 4TF devices versus 5TF devices on load to ultimate failure and load to a 2 mm gap was also compared. Methods: Ex vivo biomechanical study; unbalanced incomplete block (horse) design. Methods: Cadaveric equine forelimb superficial digital flexor tendon (n = 20 paired tendons). Methods: Ten tendon pairs were selected randomly and repaired with a 3LP and 4TF pattern, and 10 tendon pairs...
Computed Tomographic Tenography of Normal Equine Digital Flexor Tendon Sheath: An Ex Vivo Study. Aim of this study was to document the normal computed tomographic tenography findings of digital flexor tendon sheath. Six ex vivo normal equine forelimbs were used. An axial approach was used to inject 185 mg/mL of iopamidol in a total volume of 60 mL into the digital flexor tendon sheaths. Single-slice helical scans, with 5 mm thickness, spaced every 3 mm, for a pitch of 0.6, and with bone algorithm reconstruction, were performed before and after injections of contrast medium. To obtain better image quality for multiplanar reconstruction and 3D reformatting, postprocessing retrorecon...
Sympathetic innervation of the suprasesamoidean region of the deep digital flexor tendon in the forelimbs of horses. The purpose of this study was to delineate the pattern of sympathetic innervation in the suprasesamoidean region of the deep digital flexor tendon (DDFT) in horses using immunohistochemical staining (IHC) for tyrosine hydroxylase (TH) and alpha-1 adrenergic receptor (α1-AR). Fourteen forelimbs were collected from 10 horses. Longitudinal sections of the suprasesamoidean region of healthy DDFTs were harvested. Most of the sympathetic innervation was found to be in the walls of blood vessels. The tendon tissue proper was sparsely innervated, with a lesser degree of innervation within the dorsal ...
Evaluation of mean echogenicity of tendons and ligaments of the metacarpal region in neonatal foals: A preliminary study. The aims of this research were to evaluate mean echogenicity (ME) of the deep and superficial digital flexor tendons (DDFT and SDFT), the interosseous muscle (IM), and the accessory ligament of the deep digital flexor tendon (ALDDFT) of the metacarpal region in neonatal foals, and determine the effect of sex, side and body weight on this quantitative ultrasonographic evaluation. Thirteen orthopedically sound neonatal foals were examined. Four areas of study (1A, 1B, 2A, 2B) were identified. Transverse scans of the DDFT, SDFT, IM and ALDDFT were obtained, recorded, and analyzed. The most echoge...
Saline Arthrography of the Distal Interphalangeal Joint for Low-Field Magnetic Resonance Imaging of the Equine Podotrochlear Bursa: Feasibility Study. Abnormalities of the deep digital flexor tendon, navicular bone, and collateral sesamoidean ligament can be difficult to visualize using magnetic resonance imaging (MRI) if bursal fluid is absent. The use of saline podotrochlear bursography improves podotrochlear apparatus evaluation, however, the technique has disadvantages. The objective of this prospective feasibility study was to describe saline arthrography of the distal interphalangeal joint as an alternative technique for improving MRI visualization of the deep digital flexor tendon, navicular bone, collateral sesamoidean ligament, and ...
Correlation of radiographic measurements of structures of the equine foot with lesions detected on magnetic resonance imaging. There are few studies on the correlations between radiographic measurements of the foot and abnormalities of specific structures found with magnetic resonance imaging (MRI). Objective: To document the relationship between radiographic measurements of the equine foot and the presence of lesions in the foot on MRI. We hypothesised that different radiographic measurements would be associated with specific lesions detected by MRI. Methods: Retrospective analysis of radiographs and MRI studies. Methods: Seventy-four feet from 52 lame horses were included. Twenty parameters were measured on radiogra...
An optimised injection technique for the navicular bursa that avoids the deep digital flexor tendon. Injection of the navicular bursa is commonly performed from the palmar aspect of the limb, which results in penetration of the deep digital flexor tendon (DDFT). Objective: To report a radiographic guided injection from the lateral aspect of the limb that avoids puncture of the DDFT and to assess synovial and soft tissue penetration by the needle. Methods: Prospective clinical and cadaveric study. Methods: Prospective analysis of cadaver limbs and clinical cases in which the navicular bursa was injected from the lateral aspect. Cadaver limbs were placed in a stand to simulate weight bearing an...
Is there an association between clinical features, response to diagnostic analgesia and radiological findings in horses with a magnetic resonance imaging diagnosis of navicular disease or other injuries of the podotrochlear apparatus? Previous descriptions of the clinical features of navicular disease occurred before the widespread use of magnetic resonance imaging (MRI) allowed a more definitive diagnosis of foot pain. The objective of this study was to compare the clinical features of horses with lesions of the podotrochlear apparatus with those with other causes of foot pain. It was hypothesised that primary navicular bone disease would be associated with more advanced radiological findings than other diagnoses. A retrospective study was performed of all horses examined at a referral centre with a definitive diagnosis of...
Musculoskeletal lesions and lameness in 121 horses with carpal sheath effusion (1999-2010). Equine carpal sheath effusion has multiple etiologies. The purpose of this retrospective study was to describe the prevalence of distinct musculoskeletal lesions lameness in a sample of horses with a clinical diagnosis of carpal sheath effusion. A total of 121 horses met inclusion criteria. Seventy-four percent (89/121) of horses were lame at presentation; middle-aged (9-18 years, 80%) and older (> 18 years, 85%) horses were lame more frequently than young horses (< 9 years, 44%). Ninety-three percent (113/121) were diagnosed with osseous and/or soft tissue abnormalities. Of these 113 ho...
Do low field magnetic resonance imaging abnormalities correlate with macroscopical and histological changes within the equine deep digital flexor tendon? Correlating magnetic resonance (MR) imaging and histopathological findings is essential to validate low field MR imaging in lame horses. This study aimed to compare signal changes in the deep digital flexor tendon (DDFT) of the distal limb on low field MR imaging with macroscopical and histological findings. Cadaver limbs from lame horses with DDFT lesions were selected. The DDFT MR imaging findings and histopathological results were graded, and macroscopical abnormalities were recorded. There was a strong correlation between MR imaging and histopathology grades (rs = 0.76, p < 0.00...
Effect of autologous adipose tissue-derived mesenchymal stem cells on neovascularization of artificial equine tendon lesions. To investigate whether autologous adipose tissue-derived mesenchymal stem cells (AT-MSCs) treatment of tendon lesions increases neovascularization during tendon healing. Methods: A standardized surgical model was used to create lesions in both front limb superficial digital flexor tendons (SDFTs) of nine horses. Either AT-MSCs or control substance was injected intralesionally 2 weeks post-surgery. Color Doppler ultrasonography of SDFTs was performed at regular intervals. Horses were euthanized 22 weeks post-treatment and SDFTs were harvested for histology. Results: The color Doppler ultrasonog...
Identification of surgically-induced longitudinal lesions of the equine deep digital flexor tendon in the digital flexor tendon sheath using contrast-enhanced ultrasonography: an ex-vivo pilot study. Longitudinal tears in the lateral aspect of the deep digital flexor tendon are the most common causes of pain localised to the equine digital flexor tendon sheath. However conventional ultrasonographic techniques provide limited information about acute lesions. Ultrasonographic contrast agents are newly developed materials that have contributed to advancement in human diagnostic imaging. They are currently approved for intravenous use in human and animal models. In this study we described intrathecal use in the horse. This study was undertaken to evaluate the reliability of standard and angle ...
The use of magnetic resonance imaging in diagnosing equine deep digital flexor tendinopathies–own experience. Deep digital flexor tendinopathy is a common problem in horses of different athletic disciplines. Nowadays, the use of magnetic resonance imaging is considered to be a noninvasive and superior choice for recognizing bone and soft tissue pathologies especially related to difficult to access structures within the hoof capsule.
Outcome of palmar/plantar digital neurectomy in horses with foot pain evaluated with magnetic resonance imaging: 50 cases (2005-2011). There is limited knowledge of the foot lesions that influence the outcome of palmar/plantar digital neurectomy (PDN). Objective: 1) To report the short- and long-term outcomes of horses that underwent PDN to alleviate chronic foot pain due to lesions diagnosed by magnetic resonance imaging (MRI) and 2) factors that may influence the outcome of PDN. Methods: Multicentre retrospective study. Methods: Medical records of 50 horses subjected to PDN due to chronic foot pain were reviewed. Age, breed, sex, athletic activity, duration of lameness, affected limb(s), response to anaesthesia of the palma...
In vivo measurements of flexor tendon and suspensory ligament forces during trotting using the thoroughbred forelimb model. The purpose of this study was to create a lower forelimb model of the Thoroughbred horse for measuring the force in the superficial and deep digital flexor tendons (SDFT and DDFT), and the suspensory ligament (SL) during a trot. The mass, centers of gravity, and inertial moments in the metacarpus, pastern, and hoof segments were measured in 4 Thoroughbred horses. The moment arms of the SDFT, DDFT, and SL in the metacarpophalangeal (fetlock) and distal interphalangeal (coffin) joints were measured in 7 Thoroughbred horses. The relationship between the fetlock joint angle and the force in the SL...
Frontal plane fractures of the accessory carpal bone and implications for the carpal sheath of the digital flexor tendons. Accurate radiological and ultrasonographic descriptions of frontal plane fractures of the accessory carpal bone (ACB) are lacking, and implications of these fractures for the carpal sheath and its contents have not previously been reported. Objective: Aims were as follows: 1) to describe the location and radiological features of frontal plane fractures of the ACB; 2) to document communication of displaced fractures with the carpal sheath and consequent injury to the deep digital flexor tendon (DDFT); 3) to describe ultrasonographic identification of lesions; and 4) to report tenoscopic evaluat...
Aseptic tenosynovitis of the carpal flexor sheath caused by rupture of the accessory ligament of the deep digital flexor tendon. 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...
The effect of Clostridium botulinum toxin type A injections on motor unit activity of the deep digital flexor muscle in healthy sound Royal Dutch sport horses. Therapeutic reduction of the activity of the deep digital flexor (DDF) muscle may play a role in treatment of laminitic horses. Clostridium botulinum toxin type A induces reduced muscle activity and has a spasmolytic effect in horses. In this study, the effectiveness of 200 IU C. botulinum toxin type A on reduction of DDF muscle activity was measured in seven healthy, sound, adult Royal Dutch sport horses. C. botulinum toxin type A was injected using ultrasound and electromyographic (EMG) guidance. The effectiveness was assessed by interference pattern analysis (IPA) and motor unit action pote...
Effect of Clostridium botulinum toxin type A injections into the deep digital flexor muscle on the range of motion of the metacarpus and carpus, and the force distribution underneath the hooves, of sound horses at the walk. In the treatment of laminitis, reducing deep digital flexor muscle (DDFM) activity might diminish its pull on the distal phalanx, thereby preventing displacement and providing pain relief. Injection of Clostridium botulinum toxin type A into the DDFM of horses is potentially therapeutic. However, the effects of C. botulinum toxin type A on the gait characteristics of sound horses at the walk are not known. The aim of this study was to test if a reduced DDFM activity would lead to (1) alterations of the sagittal range of motion of the metacarpus (SROM) and range of motion of the carpal joint (C...
Contrast-enhanced computed tomographic evaluation of the deep digital flexor tendon in the equine foot compared to macroscopic and histological findings in 23 limbs. Distal deep digital flexor tendinopathy is an important cause of foot lameness in horses that is difficult to diagnose with radiography and ultrasonography. Magnetic resonance imaging is a well-accepted and validated technique for the identification of deep digital flexor tendon (DDFT) lesions, but has some practical and financial drawbacks. Contrast-enhanced computed tomography (CECT) has been proposed as a suitable alternative, but validation studies are currently lacking. Objective: To assess the accuracy of CECT for the identification and characterisation of deep digital flexor tendinopath...
Comparison of basilar and axial sesamoidean approaches for digital flexor tendon sheath synoviocentesis and injection in horses. To define a method for the basilar sesamoidean approach (BSA) to the digital flexor tendon sheath (DFTS) in horses and compare it with the axial sesamoidean approach (ASA) for DFTS synoviocentesis and injection. Methods: Evaluation study. Methods: 12 healthy adult mares without evidence of abnormalities related to the lower limbs. Methods: Each horse had 1 forelimb and 1 hind limb assigned to each DFTS approach (basilar vs axial, relative to the proximal sesamoid bones) in a Latin square design. The order of horses and of limb injection for each horse was randomly selected. All procedures were...
Deep digital flexor tendon injury within the hoof capsule; does lesion type or location predict prognosis? The type and location of deep digital flexor tendon (DDFT) lesions may be important in predicting outcome. The objectives of this study were to determine the frequency of different types of DDFT lesions within the hoof capsule and to determine whether lesion type predicts return to athletic activity. Lesions of the DDFT were divided into: core lesions, dorsal border lesions and parasagittal splits. Lesion location was documented, and follow-up information was obtained by telephone survey at least 18 months after diagnosis. Of 168 horses with primary DDFT injury, 54 horses had dorsal border les...
Helical sub-structures in energy-storing tendons provide a possible mechanism for efficient energy storage and return. The predominant function of tendons is to position the limb during locomotion. Specific tendons also act as energy stores. Energy-storing (ES) tendons are prone to injury, the incidence of which increases with age. This is likely related to their function; ES tendons are exposed to higher strains and require a greater ability to recoil than positional tendons. The specialized properties of ES tendons are thought to be achieved through structural and compositional differences. However, little is known about structure-function relationships in tendons. This study uses fascicles from the equine s...
Distribution and persistence of technetium-99 hexamethyl propylene amine oxime-labelled bone marrow-derived mesenchymal stem cells in experimentally induced tendon lesions after intratendinous injection and regional perfusion of the equine distal limb. Intralesional (i.l.) injection is currently the most commonly used technique for stem cell therapy in equine tendon injury. A comparison of different techniques of injection of mesenchymal stem cells for the treatment of tendon lesions is required. Objective: We hypothesised that vascular perfusion of the equine distal limb with mesenchymal stem cells (MSCs) would result in preferential distribution of MSCs to acute tendon injuries. Methods: In vivo experimental study. Methods: Lesions were surgically induced in forelimb superficial digital flexor tendons of 8 horses. Three or 10 days after le...
Vascular abnormalities of the distal deep digital flexor tendon in 8 draught horses identified on histological examination. The purpose of this study was to provide a detailed description of the vascular changes in the distal part of deep digital flexor tendon (DDFT). Eight isolated forelimbs were collected from 8 horses with DDF tendinopathy diagnosed post-mortem by ultrasound and gross anatomopathological examination. The samples were fixed in 10% neutral buffered formalin, softened in 4% phenol and dehydrated with ethylic alcohol. Goldner's Trichrome staining method was used. The histopathological examination revealed vascular proliferation associated with structural disorders of blood vessels. Angiogenesis, fib...
Magnetic resonance imaging of plantar soft tissue structures of the tarsus and proximal metatarsus in foals and adult horses. The object of this study was to describe previously defined soft tissue structures by using spin and gradient sequences in a 0.5 Tesla magnetic resonance system in order to improve the characterisation of tendon and ligaments at the plantar region of the equine tarsus and metatarsus while considering possible age-related variations. Methods: Cadaveric hindlimbs from twenty-two Warmblood horses with an age range from one month to twenty-five years were examined in spin and gradient echoes. The proximal suspensory ligament from six limbs was dissected to assign the signal intensities histologica...
Magnetic resonance and radiographic diagnosis of osseous resorption of the flexor surface of the distal phalanx in the horse. Osseous resorption of the flexor surface of the distal phalanx of the horse has been identified previously using magnetic resonance (MR) imaging; however, little is known about the prevalence and characteristics of this lesion. Objective: To establish the MR prevalence of resorptive lesions in the flexor surface of the distal phalanx and identify concurrent lesions associated with this finding and associations between the MR and radiographic findings. Methods: Horses with distal extremity MR and radiographs performed within 2 weeks of each other were included in the study. The flexor surface o...
Muscle and tendon heating rates with therapeutic ultrasound in horses. To (1) determine the temperature change in equine tendon and muscle during therapeutic ultrasound and (2) develop guidelines for treating horses for muscular or tendinous injury using therapeutic ultrasound. Methods: Experimental, in vivo study. Methods: Adult horses (n = 10). Methods: Thermistors were inserted in the superficial and deep digital flexor tendons (SDFT and DDFT) of the thoracic limbs of 10 adult horses. On the left, 3.3 MHz therapeutic continuous ultrasound was done for 10 minutes at an intensity of 1.0 W/cm(2) and for the right thoracic limb at 1.5 W/cm(2). Thermistors were pla...
Tenosynoviotomy for sepsis of the digital flexor tendon sheath in 9 horses. To describe a tenosynoviotomy technique for treatment of sepsis of the digital flexor tendon sheath (DFTS) in horses and report long-term outcome. Methods: Case series. Methods: Horses (n = 9). Methods: Horses were positioned in lateral recumbency with the affected limb uppermost. A linear incision was made just lateral to the mesotenon beginning 5 cm proximal to the apices of the proximal sesamoid bones, extending 2 cm distal to the bifurcation of the superficial digital flexor tendon (SDFT). The incision was continued through the skin, subcutaneous tissue, palmar/plantar annular ligament, an...