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Topic:Fetlock Joint

The fetlock joint in horses is a complex articulation located between the cannon bone and the proximal phalanx, playing a pivotal role in equine locomotion. This joint is characterized by its hinge-like structure, allowing for flexion and extension movements essential for a horse's gait. The fetlock joint is supported by a network of ligaments, tendons, and synovial fluid that contribute to its stability and function. Common conditions affecting the fetlock joint include inflammation, osteoarthritis, and injuries to the supporting soft tissues. This section provides access to peer-reviewed studies and scholarly articles that explore the anatomy, biomechanics, and pathologies associated with the fetlock joint in horses.
Lateromedial and oblique radiographs detect most fetlock pathologies as effectively as a full series in horses.
Equine veterinary journal    August 13, 2025   doi: 10.1111/evj.70073
Northwood A, Berner D.Radiographic protocols for the metacarpo-/tarsophalangeal joint during pre-purchase examinations (PPE) vary internationally, but their impact on pathology detection remains unclear. Optimising imaging protocols is essential to balance diagnostic accuracy with workflow efficiency and radiation exposure. Objective: To evaluate the effect of different radiographic view combinations on fetlock pathology detection and observer agreement in a PPE context; hypothesising that detection rates vary with view selection. Methods: Retrospective observational study. Methods: Two observers reviewed fetlock r...
Mosaic arthroplasty in equine stifle and fetlock joints: A retrospective study of 31 cases between 1998 and 2023.
Veterinary surgery : VS    June 27, 2025   doi: 10.1111/vsu.14296
Pál Z, Tuska P, Vásárhelyi G, Hangody L, Hurtig M, Kaposi AD, Bodó G.To evaluate the clinical application of equine mosaic arthroplasty for joint surface repair, including outcomes and complications. Methods: Retrospective clinical study. Methods: A total of 31 horses diagnosed with subchondral bone cysts (SBCs) in the femoral condyle (22/31), distal metacarpus (7/31), or metatarsus (2/31). Methods: Medical records of horses that underwent autologous or allogeneic osteochondral graft transplantation were reviewed. Follow-up lasted at least 12 months. Success was determined in terms of improvements in lameness and post-surgical athletic performance, classified...
Direct arthroscopic approach to the distal pouch of the palmar/plantar recess of the metacarpophalangeal/metatarsophalangeal joint in horses.
Veterinary surgery : VS    June 12, 2025   doi: 10.1111/vsu.14290
Foucaud M, Haegeman L, Kadic D, Vinardell T, Mariën T, Declercq J.To describe a direct arthroscopic approach of the distal pouch of the palmar/plantar recess of the fetlock to facilitate fragment removal, highlighting its advantages over previously described arthroscopic methods for the fetlock. Additionally, to evaluate and present a retrospective case series. Methods: Ex vivo and retrospective clinical study. Methods: A total of 25 fetlocks in 23 horses. Methods: A direct approach to the distal pouch of the palmar/plantar recess of the fetlock was developed on five cadaveric limbs. Arthroscopic anatomy and landmarks were examined. The approach was clinical...
Western performance horses with fetlock lameness demonstrate radiographic evidence of chronic exercise remodelling.
Equine veterinary journal    May 19, 2025   doi: 10.1111/evj.14514
Solum G, Acutt E, Johnson SA, Zhou T, Contino EK, Donnell JR, Donnell A, Frisbie DD.Pathological changes of the fetlock joint are well documented in Thoroughbreds, but little information is available describing the common radiographic findings in western performance horses with fetlock lameness. Objective: To describe radiographic findings in western performance horses with fetlock lameness. It was hypothesised that the degree of lameness would correlate with the severity of radiographic findings. Methods: Retrospective case series. Methods: Retrospective review (2012-2022) of horses with lameness isolated to the fetlock joint via intra-articular analgesia and corresponding r...
Treatment outcomes for equine osteoarthritis with mesenchymal stromal cells and hyaluronic acid.
Equine veterinary journal    May 13, 2025   Volume 57, Issue 5 1245-1254 doi: 10.1111/evj.14531
Luque RM, Henderson B, McCorkell TC, Alizadeh AH, Russell KA, Koch TG, Koenig J.Mesenchymal stromal cells (MSCs) are widely used to treat osteoarthritis (OA). Optimising dose, timing, and safety while comparing efficacy with standard therapies like hyaluronic acid (HA) is essential for their standardisation. Objective: To assess the safety and efficacy of equine umbilical cord-derived (eCB) MSCs in client-owned horses with fetlock or carpus OA. Methods: Prospective single-blinded randomised clinical study. Methods: Horses diagnosed with fetlock or carpus OA via intra-articular (IA) anaesthesia were randomly assigned to receive either 10 or 20 million eCB-MSCs in HA or 3â€...
Combined standing low-field magnetic resonance imaging and fan-beam computed tomographic diagnosis of fetlock region pain in 27 sports horses.
Equine veterinary journal    March 24, 2025   doi: 10.1111/evj.14504
Nagy A, Dyson SJ.There is no description of comparative magnetic resonance imaging (MRI) and fan-beam computed tomography (CT) findings in the fetlock of lame sports horses. Objective: To document low-field MRI and fan-beam CT diagnoses in the lame and nonlame limbs of sports horses with fetlock region pain, and to evaluate whether combined imaging provides superior information to either technique alone. Methods: Retrospective descriptive study. Methods: Clinical records of sports horses with pain causing lameness localised to the metacarpo/metatarsophalangeal joint region that had undergone fan-beam CT and lo...
Post-mortem computed tomography features associated with fracture of the fetlock joint in racing Thoroughbreds.
Equine veterinary journal    February 10, 2025   doi: 10.1111/evj.14465
Beck C, Hitchens PL, Whitton RC.Post-mortem studies have shown that fractures involving the metacarpophalangeal/metatarsophalangeal or fetlock joint are associated with focal areas of microdamage. Identification of computed tomography (CT) features consistent with microdamage and their association with fracture may aid in identification of horses at risk of fracture. Objective: To identify CT features associated with fracture of the metacarpophalangeal/metatarsophalangeal joint. Methods: Retrospective cohort study. Methods: Post-mortem CT images of 367 limbs from 157 Thoroughbred racehorses were graded for CT features. Multi...
The concurrent use of 2.5% polyacrylamide hydrogel and betamethasone esters for intra-articular injection is well tolerated in 10 healthy horses.
Journal of the American Veterinary Medical Association    January 31, 2025   Volume 263, Issue 4 460-467 doi: 10.2460/javma.24.10.0651
Whitaker B, Barnhard JA, Webb KR, Levine D, Green MM, Vieira MR.This study assessed the safety and tolerability of concurrent intra-articular (IA) injection of 2.5% polyacrylamide hydrogel (2.5% iPAAG) and betamethasone sodium phosphate and betamethasone acetate esters (BME) in the metacarpophalangeal joints (MCPJs) of healthy horses. Methods: 10 healthy therapeutic riding horses were enrolled in this open-label safety study from August 1 to September 14, 2023. Inclusion criteria required normal physical examinations, insulin level, hematology, biochemistry, soundness at all gaits, and negative forelimb flexion tests. Screening occurred from days -14 to -0...
Cartilage defect identification on computed tomography arthrography in equine fetlock: Ex-vivo study.
Research in veterinary science    January 21, 2025   Volume 185 105548 doi: 10.1016/j.rvsc.2025.105548
CT arthrography (CTA) for evaluating cartilage defects would be beneficial in clinical practice. Since the contrast medium (CM) volume is often driven by operator experience, the aim was to evaluate the minimum volume of iodinated CM for CTA sufficient to identify iatrogenic cartilage defects in horse fetlock. The study was conducted on ex-vivo 32 distal limbs from adult horses collected at slaughter. Iatrogenic cartilage defects were arthroscopically made on fetlock, at 5 predetermined locations. Subsequently, CT scans were performed, according to the following protocol: precontrast scan, fol...
Administration of sodium hyaluronate to adult horses prior to and immediately after exercise does not alter the range of motion in either the tarsus or metacarpophalangeal joints.
Translational animal science    November 2, 2024   Volume 8 txae153 doi: 10.1093/tas/txae153
Riley JW, Chance LM, Barshick MR, Johnson SE.Hyaluronic acid (HA), a glycosaminoglycan found in joint synovial fluid, is administered to horses as an anti-inflammatory with lubrication properties. This experiment examined the effects of HA administered before and shortly after an exercise test on metacarpophalangeal (MCP; fetlock) and tibiotarsal (hock) joint range of motion (ROM). Horses were injected intravenously (IV) with placebo (4 mL, saline) or HA (4 mL, 40 mg) 24 h before performing a standardized exercise test (SET) on a high-speed treadmill and again at 6-h post-SET. Passive fetlock flexion was measured at 4 and 24 h post-...
Genetic Factors of Equine Osteochondrosis and Fetlock Osteochondral Fragments: A Scoping Review – Part 2.
Veterinary journal (London, England : 1997)    October 21, 2024   106258 doi: 10.1016/j.tvjl.2024.106258
Van Mol B, Janssens S, Oosterlinck M, Pille F, Buys N.Equine osteochondrosis and osteochondral fragments in the fetlock joint are linked to various environmental and genetic risk factors. To assess the scope of the literature linking these risk factors to the development of these osteochondral disorders, while identifying knowledge gaps and challenges to guide future research, a scoping review was performed. This article constitutes the second part of this scoping review and focuses on genetic factors, with the first part addressing environmental factors. To identify potentially relevant papers, online bibliographical databases PubMed and Web of ...
Distal sagittal forelimb conformation in young Walloon horses: Radiographic assessment and its relationship with osteochondral fragments.
PloS one    October 11, 2024   Volume 19, Issue 10 e0311965 doi: 10.1371/journal.pone.0311965
Van Cauter R, Caudron I, Lejeune JP, Rousset A, Serteyn D.Osteochondral fragments within equine joints are commonly encountered and may predispose to lameness and limitation to sport purposes. Factors leading to this condition include genetic, nutritional and environmental conditions. However, few studies have evaluated the impact of conformation traits and their correlation with osteochondrosis. This study, based on the radiographic screenings of young horses born in Wallonia (266 individuals, 532 forelimbs), evaluated the correlation between foot, fetlock conformations of the front limb, height at the withers and presence of osteochondral fragments...
Ultrasonographic assessment of equine metacarpal cartilage thickness is more accurate than computed tomographic arthrography. Hoey S, Fogarty U, McAllister H, Puggioni A, Cloak B, Richard H, Skelly C, Laverty S.Articular cartilage can be directly imaged using ultrasonography. The fetlock is a common site of osteochondrosis, with the sagittal ridge of the third metacarpal bone most commonly affected. In osteochondrosis, cartilage thickening may be an initial finding. This postmortem study investigated the ability of ultrasonography to accurately measure the dorsodistal articular cartilage of the third metacarpal bone in young horses, compared to computed tomographic arthrography (CTA) and histological measurements. A total of 33 metacarpophalangeal joints from 18 horses between the ages of 12 days and...
Environmental Factors of Equine Osteochondrosis and Fetlock Osteochondral Fragments: A Scoping Review – Part 1.
Veterinary journal (London, England : 1997)    September 27, 2024   106249 doi: 10.1016/j.tvjl.2024.106249
Van Mol B, Oosterlinck M, Janssens S, Buys N, Pille F.Various environmental and genetic risk factors are linked to the pathogenesis of equine osteochondrosis and osteochondral fragments in the fetlock joint. Therefore, a scoping review was conducted to describe current evidence linking genetic factors and environmental factors of these osteochondral disorders. This article constitutes the first part of this scoping review and focuses on environmental factors, with the second part addressing genetic factors. To identify potentially relevant papers online bibliographical databases PubMed and Web of Science were utilised, supplemented with articles ...
Injury to the palmar supporting structures of the fetlock alters limb stiffness and fetlock angle.
Equine veterinary journal    September 1, 2024   doi: 10.1111/evj.14409
Hanousek K, Fiske-Jackson A, O'Leary L, Smith RKW.In vivo measurement of limb stiffness and conformation provides a non-invasive proxy assessment of superficial digital flexor tendon (SDFT) and suspensory ligament (SL) function. Here, we compared it in fore and hindlimbs and after injury. Objective: To compare the limb stiffness and conformation in forelimbs and hindlimbs, changes with age, and following injury to the SDFT and SL. Methods: Retrospective cohort study. Methods: Limb stiffness was calculated using floor scales and an electrogoniometer taped to the dorsal fetlock. The fetlock angle and weight were simultaneously recorded five tim...
Mineralization of equine proximal sesamoid bones precedes articular cartilage and fibrocartilaginous enthesis maturation in early postgestational development.
American journal of veterinary research    July 31, 2024   1-10 doi: 10.2460/ajvr.24.04.0101
Okudaira M, Cresswell EN, Wollman CW, McDonough SP, Engiles JB, Reesink HL.To describe the development and maturation of equine proximal sesamoid bones (PSBs) in fetuses and young horses using radiography, microcomputed (micro)-CT, and histology. Methods: A descriptive study. Forelimb PSBs from 12 equids ranging in age from 105 days of gestation to 540 days postgestation were evaluated. Radiography was used for preliminary assessment of metacarpophalangeal joint and PSB mineralization, and micro-CT imaging was performed to assess mineralized PSBs. Tissue volume, bone volume fraction, height, width, depth, trabecular thickness, and anisotropy were quantified from midp...
Cone beam computed tomography and cross-sectional anatomy of the region of the fetlock in the horse (Equus caballus).
Anatomia, histologia, embryologia    July 5, 2024   Volume 53, Issue 4 e13079 doi: 10.1111/ahe.13079
Bierau J, Rott P, Röcken M, Staszyk C.This study aimed to delineate the detailed anatomy of the metacarpophalangeal (MCP) and metatarsophalangeal (MTP) joints in healthy horses using cone beam computed tomography (CBCT). The fetlock region of 15 cadaveric forelimbs and 14 cadaveric hindlimbs from nine adult horses without orthopaedic disease underwent CBCT scanning. Additionally, arthrography CBCT scans were conducted following intra-articular injection of a radiopaque contrast medium containing blue epoxy resin dye. Subsequently, limbs were frozen and sectioned to visualize anatomical structures in sectional planes corresponding ...
Athletic prognosis following arthroscopic removal of osteochondral fragments of the proximal dorsal sagittal ridge of the fetlock in Thoroughbreds intended for flat racing.
Veterinary surgery : VS    June 24, 2024   doi: 10.1111/vsu.14129
Luick ML, Khouzam NA, Pérez-Nogués M.To establish racing prognosis in Thoroughbred yearlings with proximal sagittal ridge osteochondral lesions and compare them to dorsoproximal and palmar/plantar first phalanx osteochondral lesions. Methods: A total of 47 horses had proximal sagittal ridge lesions, 34 had palmar/plantar first phalanx lesions, and 115 had dorsoproximal first phalanx lesions. Methods: Retrospective case series. Methods: Medical records of Thoroughbred yearling racing prospects treated arthroscopically for fetlock osteochondral lesions were reviewed. Data were collected from a public database, including the ability...
Auxiliary osseous findings in fetlocks of non-racing sports horses with sagittal groove disease of the proximal phalanx on low-field magnetic resonance imaging.
Equine veterinary journal    June 5, 2024   doi: 10.1111/evj.14111
Faulkner JE, Joostens Z, Broeckx BJG, Hauspie S, Mariën T, Vanderperren K.Sagittal groove disease of the proximal phalanx in equine athletes is commonly considered a bone stress injury. Repetitive hyperextension of the fetlock under high load is thought to contribute to its development. Concurrent changes are often reported in the dorsal sagittal ridge of the third metacarpus/metatarsus (MC3/MT3). Objective: To describe the spectrum of associated osseous abnormalities that are present in the fetlock in a large group of horses diagnosed with sagittal groove disease on low-field magnetic resonance imaging (MRI). Methods: Retrospective, cross-sectional. Methods: MRI im...
Prospective, longitudinal assessment of subchondral bone morphology and pathology using standing, cone-beam computed tomography in fetlock joints of 2-year-old Thoroughbred racehorses in their first year of training.
Equine veterinary journal    January 21, 2024   doi: 10.1111/evj.14048
Ciamillo SA, Wulster KB, Gassert TM, Richardson DW, Brown KA, Stefanovski D, Ortved KF.Catastrophic injuries of the fetlock joints occur in Thoroughbred racehorses and are preceded by stress-induced bone injury. Early detection of subchondral bone injury is essential to prevent irreversible damage or bone failure. Objective: To investigate the use of standing, robotic cone-beam computed tomography (CBCT) for assessing longitudinal changes in subchondral bone morphology and pathology of the fetlock joints associated with race training in young Thoroughbreds. Methods: Observational cohort study. Methods: Forty-one 2-year-old Thoroughbred racehorses were recruited prior to the star...
SNP-Based Heritability of Osteochondrosis Dissecans in Hanoverian Warmblood Horses.
Animals : an open access journal from MDPI    April 25, 2023   Volume 13, Issue 9 doi: 10.3390/ani13091462
Zimmermann E, Distl O.Before the genomics era, heritability estimates were performed using pedigree data. Data collection for pedigree analysis is time consuming and holds the risk of incorrect or incomplete data. With the availability of SNP-based arrays, heritability can now be estimated based on genotyping data. We used SNP array and 1.6 million imputed genotype data with different minor allele frequency restrictions to estimate heritabilities for osteochondrosis dissecans in the fetlock, hock and stifle joints of 446 Hanoverian warmblood horses. SNP-based heritabilities were estimated using a genomic restricted...
Identification of Heterotopic Mineralization and Adjacent Pathology in the Equine Fetlock Region by Low-Field Magnetic Resonance Imaging, Cone-Beam and Fan-Beam Computed Tomography.
Journal of equine veterinary science    February 14, 2023   Volume 126 104252 doi: 10.1016/j.jevs.2023.104252
Lin ST, Peter VG, Schiavo S, Pokora R, Patrick H, Bolas N, Foote AK, Sargan DR, Murray RC.Heterotopic mineralization in equine distal limbs has been considered an incidental finding and little is known about its imaging features. The study aimed to identify heterotopic mineralization and adjacent pathology in the fetlock region with cone-beam (CB) computed tomography (CT), fan-beam (FB) CT, and low-field magnetic resonance imaging (MRI). Images from 12 equine cadaver limbs were examined for heterotopic mineralization and adjacent pathology and verified by macro-examination. Retrospective review of the CBCT/MR images from 2 standing horses was also included. CBCT and FBCT identified...
Comparison of skeletal scintigraphy and standing 18 F-NaF positron emission tomography for imaging of the fetlock in 33 Thoroughbred racehorses. Spriet M, Arndt S, Pige C, Pye J, O'Brion J, Carpenter R, Blea J, Dowd JP.This retrospective, methods comparison study aimed to compare skeletal scintigraphy and F-NaF positron emission tomography (PET) for the detection of abnormalities in the fetlocks of Thoroughbred racehorses. Thirty-three horses (72 limbs) imaged with both scintigraphy and F-NaF PET, for investigation of lameness or poor performance related to the fetlock, were included. Seven observers, including experienced racetrack practitioners, surgery and imaging residents, and a board-certified veterinary radiologist, independently reviewed all data for evidence of increased radiopharmaceutical uptake...
Fetlock Joint Angle Pattern and Range of Motion Quantification Using Two Synchronized Wearable Inertial Sensors per Limb in Sound Horses and Horses with Single Limb Naturally Occurring Lameness.
Veterinary sciences    August 25, 2022   Volume 9, Issue 9 456 doi: 10.3390/vetsci9090456
Pagliara E, Marenchino M, Antenucci L, Costantini M, Zoppi G, Giacobini MDL, Bullone M, Riccio B, Bertuglia A.Fetlock joint angle (FJA) pattern is a sensitive indicator of lameness. The first aim of this study is to describe a network of inertial measurement units system (IMUs) for quantifying FJA simultaneously in all limbs. The second aim is to evaluate the accuracy of IMUs for quantifying the sagittal plane FJA overground in comparison to bi-dimensional (2-D) optical motion capture (OMC). 14 horses (7 free from lameness and 7 lame) were enrolled and analyzed with both systems at walk and trot on a firm surface. All enrolled horses were instrumented with 8 IMUs (a pair for each limb) positioned at t...
Longitudinal monitoring of fetlock lesions in Thoroughbred racehorses using standing 18F-sodium fluoride positron emission tomography.
American journal of veterinary research    August 18, 2022   Volume 83, Issue 10 ajvr.22.03.0062 doi: 10.2460/ajvr.22.03.0062
Pye J, Spriet M, O'Brion J, Carpenter R, Blea JA, Dowd JP.To assess the repeatability of equine 18F-sodium fluoride (18F-NaF) positron emission tomography (PET) findings, and to evaluate the ability of PET to monitor the progression of areas of increased radiopharmaceutical uptake (IRU) in the fetlocks of Thoroughbred racehorses. Methods: 25 racehorses with clinical signs related to fetlock injuries. Methods: This study is a prospective, longitudinal clinical study. Twenty-five racehorses (54 fetlocks) underwent three 18F-NaF PET scans 6 weeks apart. The first 18F-NaF PET scan was performed at the start of a 12-week period of rest from racing (lay-up...
Standardized uptake values and attenuation correction in 18 F-sodium fluoride PET of the equine foot and fetlock. Sannajust K, Spriet M, Anishchenko S, Beylin D.Maximal standardized uptake values (SUV ) are commonly used for the interpretation of PET studies. Limited information regarding the SUV of F-NaF PET in horses is currently available in the literature. The goals of this retrospective secondary analysis study were to provide reference values for F-NaF SUV in the equine distal extremity and assess the effect of attenuation correction. Nonattenuation corrected (NAC) and CT-based attenuation corrected (CTAC) SUV were obtained from 19 feet and 19 fetlocks. Twenty regions of interest (ROIs) were defined for the foot and 22 for the fetlock. Areas p...
Validation of a dedicated positron emission tomography scanner for imaging of the distal limb of standing horses. Spriet M, Edwards L, Arndt S, Wilson SS, Galuppo LD, Stepanov P, Beylin D.A positron emission tomography (PET) scanner, with an openable ring of detectors, was specifically designed to image the distal limb of standing horses. The goals of this prospective, preclinical, experimental, methods comparison study were to validate the safety of the scanner, assess image quality, and optimize scanning protocols. Six research horses were imaged three times (twice standing, once anesthetized) and six horses in active race training were imaged once under standing sedation. Multiple scans of both front fetlocks were obtained with different scan durations and axial fields of vi...
Kinematic Analysis During Straight Line Free Swimming in Horses: Part 2 – Hindlimbs.
Frontiers in veterinary science    January 31, 2022   Volume 8 761500 doi: 10.3389/fvets.2021.761500
Santosuosso E, Leguillette R, Vinardell T, Filho S, Massie S, McCrae P, Johnson S, Rolian C, David F.Swimming is used for rehabilitation and conditioning purposes in equine sports medicine. We described the swimming kinematics of the equine forelimbs in Part 1. The aim of Part 2 is to assess stifle, tarsus, and hind fetlock joints kinematics in swimming horses. The objectives were 1- to calculate and compare joint angles during swimming against passive mobilizations (PM), 2- to determine joints angular velocities during a swimming stride cycle. Methods: Eleven elite endurance horses were used to swim in a 100-meter straight pool. Underwater (swimming) and overground PM videos were recorded fr...
First phalanx exostosis in traditional equestrian horses in Western Libya.
Open veterinary journal    January 25, 2022   Volume 12, Issue 1 69-74 doi: 10.5455/OVJ.2022.v12.i1.8
Abushhiwa MH, Elmeshreghi TN, Alrtib AM, Bennour EM, Oheida AH.Orthopedic diseases involving the forelimb fetlock joint of horses other than those used in professional racing have not been widely reported in the literature. One of these problems is the exostosis on the proximal forelimb phalanx (P1), which has not been reported previously in Western Libya. The study aimed to investigate the prevalence of P1 exostosis in traditional equestrian horses (known locally as Sarj horses) of different breeds in Libya that participated in a special social event and described its clinical findings radiographic appearance. The current study involved 60 horses admitte...
Imaging and Gross Pathological Appearance of Changes in the Parasagittal Grooves of Thoroughbred Racehorses.
Animals : an open access journal from MDPI    November 24, 2021   Volume 11, Issue 12 3366 doi: 10.3390/ani11123366
Johnston GCA, Ahern BJ, Palmieri C, Young AC.(1) Background: Parasagittal groove (PSG) changes are often present on advanced imaging of racing Thoroughbred fetlocks and have been suggested to indicate increased fracture risk. Currently, there is limited evidence differentiating the imaging appearance of prodromal changes in horses at risk of fracture from horses with normal adaptive modelling in response to galloping. This study aims to investigate imaging and gross PSG findings in racing Thoroughbreds and the comparative utility of different imaging modalities to detect PSG changes. (2) Methods: Cadaver limbs were collected from twenty ...
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