The prognosis for return to athletic function for Thoroughbred racehorses in Hong Kong with injuries to the palmaroproximal aspect of the metacarpus diagnosed using low-field magnetic resonance imaging.

OBJECTIVE: To evaluate and compare the prognosis for Thoroughbred racehorses to return to galloping and racing with injuries to the palmaroproximal metacarpus diagnosed with MRI. ANIMALS: 29 flat racing Thoroughbreds at the Hong Kong Jockey Club that underwent MRI between 2014 and 2022. METHODS: Clinical, radiographic, ultrasonographic, and MRI reports were collected from veterinary clinical records, and these were combined with training and racing data. Horses were categorized on the basis of MRI diagnosis: (1) proximal suspensory ligament (PSL) involvement only, (2) PSL and concurrent proximal third metacarpal (MC3) bone involvement, and (3) proximal MC3 bone involvement only. The following were compared for prognosis for return to athletic function: return to galloping or racing, and reinjury. RESULTS: Overall, the prognosis for return to athletic function was fair, with 92% (22/24; P = .53) and 67% (16/24; P = .73) of horses returning to galloping and racing, respectively. There was a relatively low reinjury rate, with 18% (4/22) of horses reinjuring. Horses with concurrent injury to both the PSL and proximal MC3 bone (Category 2) took longer to return to gallop (median, 116; IQR, 100.5 to 160), when compared with horses having only PSL injury (median, 69; IQR, 43 to 80; P = .04). Of the 4 horses that reinjured, 3 (75%) were horses in Category 2. CLINICAL RELEVANCE: The findings from this study suggest that injuries involving both PSL and proximal MC3 bone concurrently require a longer rehabilitation period than those with PSL involvement alone.

Morphological analysis of third metacarpus cartilage and subchondral bone in Thoroughbred racehorses: An ex vivo study.

Racehorses are exposed to repetitive overload during training and competition, causing joint hyperextension, tissue fatigue, and ultimately skeletal failure. Some degree of bone changes, such as sclerosis, are expected in equine athletes, as adaptation to the biomechanical rigors of training and racing. Understanding the imaging characteristics of the equine joint surface and subchondral bone would allow earlier detection of injuries or adaptation, improving prognosis and training programs. This study sought to describe the joint surface structural patterns and the periarticular structures of the third metacarpal bone (MC3). Both forelimbs of eight horses engaged in daily training programs, aged 3-5 years, which were euthanized for reasons unrelated to the metacarpophalangeal (MCP) joints, were collected. Specimens were evaluated through macroscopic inspection, radiography, ultrasonography, and microscopic examinations, such as optical microscopy and microtomography. Analysis of the microtomography images showed that 50% of the samples had higher trabecular thickness in the lateral condyle. Comparison of each imaging examination revealed that ultrasound images were most closely related to the histological examination (p = .29) in terms of sensitivity, while macroscopic and radiographic examinations differed most between evaluators. Finally, the irregularities and modifications observed in the articular cartilage surface and subchondral bone were normal adaptations of the anatomical structures of trained racehorses, which should be considered during clinical examination.

Osteosynthesis of Fractures of the Metacarpal Neck with Self-Compressing Screw - Preliminary Analysis of 21 Cases / Osteossíntese de fraturas do colo do metacarpo com parafuso autocompressivo - Análise preliminar de 21 casos

Abstract Objective The present study aims to analyze the clinical results of the surgical treatment of metacarpal neck fractures with retrograde intramedullary fixation using cannulated headless screws (Herbert type). Methods Retrospective study of 21 closed fractures deviated from the metacarpal neck in 21 patients operated between April 2015 and November 2018. Results The sample included 19 men and 2 women. The mechanisms that caused the trauma were punching, falling to the ground and motor vehicle accident (n = 14, 5 and 2). The affected metacarpals were the 5th, 3rd, and 2nd (n = 19, 1 and 1). Surgical indications were neck-shaft diaphysis of the metacarpal > 30º for the 2nd and 3rd metacarpals and > 40º for the 5th metacarpal, shortening ≥ 5mm, rotational deviation, and the desire of the patient not to use plaster cast. In the immediate postoperative period, patients remained without immobilization and were instructed to mobilize their fingers according to tolerance. All patients had total active mobility > 240º and returned to their former occupations. All fractures consolidated and there were no reinterventions. Discussion The great advantages of the headless screw technique are its low morbidity, sufficient stability to avoid external immobilization, and reproducibility at low cost. Conclusion This is an easy, fast technique that has excellent results for the surgical treatment of displaced fractures of the neck of the metacarpals.

Resumo Objetivo O presente estudo visa analisar os resultados clínicos do tratamento cirúrgico das fraturas de colo do metacarpo com fixação intramedular retrógrada utilizando parafusos canulados sem cabeça (tipo Herbert). Métodos Estudo retrospectivo de 21 fraturas fechadas desviadas do colo do metacarpo em 21 pacientes operados entre abril de 2015 e novembro de 2018. Resultados A casuística incluiu 19 homens e 2 mulheres. Os mecanismos causadores do trauma foram soco, queda ao solo e acidente com veículo motorizado (n = 14, 5 e 2). Os metacarpos acometidos foram o V, III e II (n = 19, 1 e 1). As indicações cirúrgicas foram angulação colo-diáfise do metacarpo > 30º para os II e III metacarpos e > 40º para o V metacarpo, encurtamento ≥ 5mm, desvio rotacional e o desejo do paciente de não utilizar imobilização gessada. No pós-operatório imediato, os pacientes permaneceram sem imobilização e orientados a mobilizar os dedos conforme tolerância. Todos os pacientes ficaram com mobilidade ativa total > 240º e retornaram às suas antigas ocupações. Todas fraturas consolidaram e não houve reintervenções. Discussão As grandes vantagens da técnica com parafuso sem cabeça são sua baixa morbidade, estabilidade suficiente para não precisar de imobilização externa e reprodutibilidade com baixo custo. Conclusão Esta é uma técnica fácil, rápida, e que apresenta ótimos resultados para o tratamento cirúrgico das fraturas deslocadas do colo dos metacarpos.

Cell engraftment, vascularization, and inflammation after treatment of equine distal limb wounds with endothelial colony forming cells encapsulated within hydrogel microspheres.

BACKGROUND: Endothelial colony forming cells (ECFCs) may be useful therapeutically in conditions with poor blood supply, such as distal limb wounds in the horse. Encapsulation of ECFCs into injectable hydrogel microspheres may ensure cell survival and cell localization to improve neovascularization and healing. Autologous ECFCs were isolated from 6 horses, labeled with quantum nanodots (QD), and a subset were encapsulated in poly(ethylene) glycol fibrinogen microspheres (PEG-Fb MS). Full-thickness dermal wounds were created on each distal limb and injected with empty PEG-Fb MS, serum, ECFCs, or ECFCs encapsulated into PEG- Fb MS (ECFC/MS). Analysis included wound surface area (WSA), granulation tissue scoring (GS), thermography, collagen density staining, and immunohistochemical staining for endothelial and inflammatory cells. The purpose of this study was to track cell location and evaluate wound vascularization and inflammatory response after injection of ECFC/MS or naked ECFCs in equine distal limb wounds. RESULTS: ECFCs were found near and within newly formed blood vessels up to 3 weeks after injection. ECFC and ECFC/MS groups had the greatest blood vessel quantity at week 1 in the wound periphery. Wounds treated with ECFCs and ECFC/MS had the lowest density of neutrophils and macrophages at week 4. There were no significant effects of ECFC or ECFC/MS treatment on other measured parameters. CONCLUSIONS: Injection of microsphere encapsulated ECFCs was practical for clinical use and well-tolerated. The positive ECFC treatment effects on blood vessel density and wound inflammation warrant further investigation.

[Analysis on Injury Manners of 31 Cases of Bennett Fracture and Rolando Fracture].

OBJECTIVES: To study the injury manners of Bennett fracture and Rolando fracture and explore its identification principle of the first metacarpal base fractures. METHODS: Totally 31 cases of Bennett fracture and Rolando fracture were collected. The injury manners of cases of 19 Bennett fractures and 12 Rolando fracture were classified, and various injury manners were analysed statistically. RESULTS: The injury manners of the cases of 19 Bennett fracture and 12 Rolando fracture were divided into three types, including the first metacarpus hit hard objects during a punching, the first metacarpus hit hard objects when making fists and fell, or the first metacarpus was punched by hard objects when making fists. CONCLUSIONS: The injury mechanism of Bennett fracture and Rolando fracture is formed by a force on the first metacarpus when making fists, which transmits to the basilar part along the vertical axis of metacarpus. The inference of injury manners should be focused on the confirmation of entrusted matters.

Use of a porous cellulose membrane (Membracel®) and moxibustion for severe excoriative injury in a chilean skua (Catharacta chilensis) / Utilização de membrana celular porosa (Membracel®) e moxabustão em lesão escoriativa severa em mandrião chileno(Catharacta chilensis)

The use of alternative therapeutic approaches in wild animals has gained notoriety due to its efficiency, low cost and reduced or nonexistent stressors. The present study evaluated the efficacy of treatment of a bilateral excoriative lesion in the region of the dorsal metacarpus in a Chilean skua (Catharacta chilensis) in a rehabilitation process with the use of a porous cell membrane, sold commercially, in concomitance with moxibustion sessions with herbs (Artemisia vulgaris). The healing time of 14 days was reduced when compared to traditional techniques and proved the viability and efficacy of the treatment.(AU)

O uso de abordagens terapêuticas alternativas em animais selvagens tem ganhado notoriedade em virtude de sua eficiência, baixo custo e estímulos estressores reduzidos ou inexistentes. Este estudo avaliou a eficácia do tratamento de uma lesão escoriativa bilateral em região do dorsal metacarpo em um mandrião chileno (Catharacta chilensis) em processo de reabilitação com o uso de uma membrana celular porosa vendida comercialmente, em concomitância com sessões de moxabustão com ervas (Artemisia vulgaris). O tempo de cicatrização de catorze dias mostrou-se reduzido quando comparado ao de outras técnicas tradicionais e provou a viabilidade e eficácia do tratamento.(AU)

Subchondral bone microdamage accumulation in distal metacarpus of Thoroughbred racehorses.

BACKGROUND: Microdamage accumulation leads to subchondral bone injury and/or fracture in racehorses. An understanding of this process is essential for developing strategies for injury prevention. OBJECTIVES: To quantify subchondral bone microdamage in the third metacarpal bone of Thoroughbred racehorses at different stages of the training cycle. STUDY DESIGN: Cross-sectional. METHODS: Bone blocks from the palmar aspect of the medial condyles of third metacarpal bones from 46 racing Thoroughbred horses undergoing post-mortem were examined with micro computed tomography (microCT) to detect calcified microcracks, and light microscopy to quantify bulk stained microcracks. Racing and training histories were obtained for comparison with microdamage data using regression modelling. RESULTS: Subchondral bone microcracks were observed in all bones with at least one method. Microdamage grade was greater in older horses, levelling-off for horses 5 years and older (quadratic term P = 0.01), and with lower bone material density in the parasagittal groove (P = 0.02). Microcrack density was higher in older horses (P = 0.004), and with higher bone volume fraction (BV/TV) in the parasagittal groove in horses in training (interaction effect, P = 0.01) and lower in horses resting from training (P = 0.02). MAIN LIMITATIONS: Cross-sectional data only. Incomplete detection of microdamage due to the limits of resolution of microCT and lack of three-dimensional imaging with microscopy. Multicollinearity between variables that indicated career progression (e.g. age, number of career starts, duration of training period) was detected. CONCLUSIONS: Fatigue damage in the distal metacarpal subchondral bone is common in Thoroughbred racehorses undergoing post-mortem and appears to accumulate throughout a racing career. Reduced intensity or duration of training and racing and/or increased duration of rest periods may limit microdamage accumulation. Focal subchondral bone sclerosis indicates the presence of microdamage.

Magnetic resonance imaging findings of the proximal metacarpus in Quarter Horses used for cutting: Retrospective analysis of 32 horses 2009-2012.

BACKGROUND: Injury to the proximal suspensory ligament is a common cause of lameness in cutting horses. Radiographic and ultrasonographic imaging of lesions responsible for lameness can provide ambiguous results. MRI provides the most comprehensive diagnostic imaging evaluation of lesions specifically affecting cutting horses. OBJECTIVES: To describe the distribution and severity of bone and soft tissue lesions present in the proximal metacarpus of Quarter Horse cutting horses and to assess the impact of these lesions on return to competition. STUDY DESIGN: Retrospective case series. METHODS: Retrospective analysis of 32 cutting horses referred for MRI of the proximal metacarpus between 2009 and 2012 with a 2-year follow-up period. MRI studies were evaluated by a board-certified veterinary radiologist; the severity of lesions was graded from 0 (absent) to 3 (severe). RESULTS: A total of 20 right and 24 left forelimbs (12 bilateral studies) of 32 horses were evaluated. The most common findings were: third metacarpal (McIII) sclerosis at the proximal suspensory ligament (PSL) origin (42/44), McIII resorption at the PSL origin (32/44), PSL dorsal margin fibre irregularity (30/44) and McIII bone contusion (22/39). Of the 30 horses, 22 horses successfully returned to competition, irrespective of severity of injury. Strong correlation exists between the degree of resorption in the palmar cortex of proximal McIII, degree of McIII sclerosis and severity of dorsal margin fibre irregularity. MAIN LIMITATIONS: Statistical significance was limited by small study population. Further analysis of prognosis was limited by availability of comprehensive medical records. CONCLUSIONS: Cutting horses with proximal metacarpal pain have significant pathological change within the proximal suspensory ligament and its enthesis on the palmar cortex of McIII. Severity of lesions and degree of lameness at the time of diagnosis does not influence return to performance. Accurate diagnosis of proximal metacarpal lesions based on MRI offers clinicians the capacity to select treatment protocols targeted to each disease process.

Physeal Fractures in Foals.

Physeal fractures are common musculoskeletal injuries in foals and should be included as a differential diagnosis for the lame or nonweightbearing foal. Careful evaluation of the patient, including precise radiographic assessment, is paramount in determining the options for treatment. Prognosis mostly depends on the patient's age, weight, and fracture location and configuration.

Open reduction and internal fixation for intraarticular fracture of metacarpal head.

Intraarticular fracture of the metacarpophalangeal (MP) joint presents complex problems related to the sophisticated functional aspects of the hand. Injury to the metacarpal head may have a severe effect on hand function but few studies have investigated the management of this condition. In this study, we applied open reduction and internal fixation for the displaced fracture of the metacarpal head and report the clinical and radiographic outcomes of our experience. Thirteen patients (12 men, 1 woman; mean age 21 years) were included in this study, and medical records and radiographs were reviewed retrospectively. The average follow-up period was 12.5 months. Range of motion (ROM) and Disabilities of the Arm, Shoulder, and Hand (DASH) scores were analyzed, and functional results and serial radiographs were investigated for the maintenance of articular congruity and fracture union. The injured fingers were 5 long, 4 small, 2 ring, and 2 index. Five cases were fixed with K­wires, 5 cases with headless screws, and 3 cases with screw and K­wire. The average range of injured MP joint motion was 89°, total active range of motion (TAM) was 265°, and the average DASH score was 3.8 at the last follow-up. All patients showed fracture union on the radiographs and no patient showed significant articular surface incongruence or degenerative change. Open reduction and internal fixation of the metacarpal head fracture had favorable outcomes in our study. The authors suggest accurate reduction and stable fixation for better functional results in metacarpal head fractures.

Metacarpal stress fracture in amateur tennis player - an uncommon fracture / Fratura por estresse do metacarpo em tenista amador - Uma fratura incomum

ABSTRACT Most stress fractures occur in the lower limbs and are rarely observed in the , upper limbs. The second metacarpal is the longest of all the metacarpals and has the largest base, articulating with the trapezium, trapezoid, capitate, and third metacarpal. In athletes, stress fractures in non-weight bearing joints are uncommon. Therefore, the shaft of the second metacarpal bone undergoes a higher load - the maximum tension at the base of the second metacarpal is amplified when the hand grasps a tool such as a tennis racquet.

RESUMO A maioria das fraturas por estresse ocorre nos membros inferiores, raramente nos superiores. O segundo metacarpo é o mais longo e com a base mais larga, articula-se com o trapézio, trapezoide, capitato e terceiro metacarpo. As fraturas por estresse em atletas são incomuns nas articulações sem carga. Portanto, a diáfise do segundo metacarpo sofre carga elevada - a tensão máxima na base do segundo metacarpo é amplificada quando a mão agarra uma ferramenta tal como uma raquete.

Return to Play After Hand and Wrist Fractures.

Wrist and hand injuries are common among athletes, and can lead to considerable disability. Dislocations and soft tissue injuries are common and require prompt recognition and treatment. Accurate diagnosis and early immobilization are often key to getting players back to their sport early. Some injuries require surgery; operative intervention allows the player to return to their sport more quickly or with less long-term disability. This article discusses the spectrum of injury from distal radius fractures to mallet fingers, and offers some general guidelines for the surgeon in how to counsel and treat athletes with these problems.

Clenched fist injury complicated by septic arthritis and osteomyelitis treated with negative pressure wound therapy: One case report.

We reported a 30 years old man who suffered a bite wound of the right hand in a fight. Two days after the injury, he was admitted in emergency because of stab wound above the head of the third metacarpal bone. He presented the swelling, redness, pain and fever. Primary revision confirmed only partial lesion of the extensor apparatus. During the following days, we recorded a deterioration of local findings and magnetic resonance imaging revealed osteomyelitis and septic arthritis of the thirdmetacarpophalangeal joint. The wound was then revised several times using negative pressure wound therapy in combination with intravenous antibiotics. After resolution of clinical and laboratory findings, the wound was finally closed by delayed primary suture. Clenched fist injury is a medical emergency that requires immediate surgical revision. We treated clenched fist injury with the development of septic arthritis and osteomyelitis with negative pressure wound therapy and obtained good outcomes.

Transforming growth factor-ß (TGF-ß) expression is increased in the subsynovial connective tissue in a rabbit model of carpal tunnel syndrome.

Carpal tunnel syndrome (CTS) is an idiopathic disease that results from increased fibrosis of the subsynovial connective tissue (SSCT). A recent study found overexpression of both transforming growth factor-ß (TGF-ß) and connective tissue growth factor (CTGF) in the SSCT of CTS patients. This study investigated TGF-ß and CTGF expression in a rabbit model of CTS, in which SSCT fibrosis is induced by a surgical injury. Levels of TGF-ß1 and CTGF at 6, 12, 24 weeks after injury were determined by immunohistochemistry A significant increase in TGF-ß1 and a concomitant significant increase in CTGF were found at 6 weeks, in addition to higher cell density compared to normal (all p<0.05), Interestingly, CTGF expression was reduced at 12 and 24 weeks, suggesting that an initial insult results in a time limited response. We conclude that this rabbit model mimics the fibrosis found in human CTS, and may be useful to study pathogenetic mechanisms of CTS in vivo.

Interobserver variability in the treatment of little finger metacarpal neck fractures.

PURPOSE: To address the null hypothesis that surgeons shown radiographs of little finger metacarpal neck fractures with measured fracture angulation would recommend surgery as often as surgeons shown unmarked radiographs. METHODS: Members of the Science of Variation Group, an international collaboration of fully trained orthopedic and trauma surgeons, were asked to review 20 little finger metacarpal neck fracture cases, which included a vignette and 3 high-quality radiographs. Members were then randomized to review radiographs with or without measured fracture angulation on the lateral view and select operative or nonoperative management. RESULTS: Surgeons shown radiographs with measured angulation were more likely to recommend surgery, and there was less variability among these surgeons, particularly for fractures with less angular deformity. CONCLUSIONS: Measured fracture angulation has a small but significant influence on treatment recommendations for little finger metacarpal neck fractures. TYPE OF STUDY/LEVEL OF EVIDENCE: Diagnostic III.

Intra-focal reduction and percutaneous fixation of neck fractures of the fifth metacarpal: description of surgical technique / Redução intrafocal e fixação percutânea das fraturas do colo do quinto metacarpo - Descrição de técnica cirúrgica

OBJECTIVE: to demonstrate a surgical technique for treating neck fractures of the fifth metacarpal, by means of reduction through intra-focal manipulation and percutaneous fixation using Kirschner wires, with the aims of making it easier to achieve and maintain the reduction during the operation and enabling reduction of these fractures even if a fibrous callus has formed. METHODS: a series of ten patients with neck fractures of the fifth metacarpal presenting palmar angles greater than 30◦ underwent the surgical technique described, as examples, and their results were evaluated through postoperative radiographs and clinical examinations. RESULTS: all the patients achieved reductions that were close to anatomical and evolved to consolidation of the fracture in the position obtained. CONCLUSION: the surgical technique described is effective, easy to carry out, minimally invasive and low-cost, thereby enabling adequate clinical and radiographic reduction, even in subacute fractures already presenting a fibrous callus...

OBJETIVO: demonstrar uma técnica cirúrgica para o tratamento das fraturas do colo do quinto metacarpo por meio de redução por manipulação intrafocal e fixação percutânea com fios de Kirschner, visando a facilitar a obtenção e manutenção da redução no intraoperatório e possibilitar a redução dessas fraturas, ainda que com calo fibroso formado. MÉTODOS: dez pacientes portadores de fratura do colo do quinto metacarpo com angulação palmar superior a 30◦ foram submetidos, como exemplos, à técnica cirúrgica descrita. Os resultados foram avaliados por meio de radiografias e exame clínico pós-operatório. RESULTADOS: todos os pacientes obtiveram redução próxima da anatômica e evoluíram para consolidação da fratura na posição obtida. CONCLUSÃO: a técnica cirúrgica descrita é eficaz, de simples execução, minimamente invasiva, de baixo custo e permite redução clínica e radiográfica adequadas, mesmo em fraturas subagudas com calo fibroso formado...

Identification of cartilage injury using quantitative multiphoton microscopy.

OBJECTIVE: Cartilage injury can lead to post-traumatic osteoarthritis (PTOA). Immediate post-trauma cellular and structural changes are not widely understood. Furthermore, current cellular-resolution cartilage imaging techniques require sectioning of cartilage and/or use of dyes not suitable for patient imaging. In this study, we used multiphoton microscopy (MPM) data with FDA-approved sodium fluorescein to identify and evaluate the pattern of chondrocyte death after traumatic injury. METHOD: Mature equine distal metacarpal or metatarsal osteochondral blocks (OCBs) were injured by 30 MPa compressive loading delivered over 1 s. Injured and control sites were imaged unfixed and in situ 1 h post-injury with sodium fluorescein using rasterized z-scanning. MPM data was quantified in MATLAB, reconstructed in 3-D, and projected in 2-D to determine the damage pattern. RESULTS: MPM images (600 per sample) were reconstructed and analyzed for cell death. The overall distribution of cell death appeared to cluster into circular (n = 7) or elliptical (n = 4) patterns (p = 0.006). Dead cells were prevalent near cracks in the matrix, with only 26.3% (SE = 5.0%, p < 0.0001) of chondrocytes near cracks being viable. CONCLUSION: This study demonstrates the first application of MPM for evaluating cellular-scale cartilage injury in situ in live tissue, with clinical potential for detecting early cartilage damage. With this technique, we were able to uniquely observe two death patterns resulting from the same compressive loading, which may be related to local variability in matrix structure. These results also demonstrate proof-of-concept MPM diagnostic use in detecting subtle and early cartilage damage not detectable in any other way.