Evaluating alternative temperature measurement sites in cats within a home environment: A comparison with rectal temperature.

OBJECTIVE: This study aimed to compare rectal temperature (RT) with temperatures measured in the pinna, cornea, medial canthus, gingiva, metacarpal pad and axillary region of cats in a home environment. ANIMALS STUDIED: Five healthy mixed-breed cats (two females and three males) owned by a veterinarian were used. PROCEDURES: All temperature measurements were conducted by the owner by using an infrared camera in the same room and initiated with the pinna, followed by the cornea, medial canthus, gingiva and metacarpal pad. Subsequently, axillary temperature (AT) and RT were recorded by a digital thermometer, respectively. The time taken for a single AT and RT measurements was recorded. RESULTS: The average measurement time for RT was 17.34 ± 0.89 s, with a range of 8-32 s, whereas AT measurements took an average of 46.72 ± 1.16 s, with a range of 29-69 s. AT emerged as a superior alternative measurement site compared to others, exhibiting the lowest bias and the highest proportion of readings within the limits of clinical agreement. The mean difference between RT and AT, with 95% limits of agreement for the differences, was -0.26 (-1.13 to 0.61). CONCLUSIONS: Anatomical regions were not all interchangeable with the rectum for assessing body temperature (BT), with AT recording the highest level of agreement with RT. When RT is not possible, AT could be considered as an alternative for monitoring BT in clinically healthy cats that live in a home environment.

Epidemiologic trends in hand injuries in the National Football League from 2009-2010 to 2019-2020.

OBJECTIVES: In American football, hand injuries have been shown to negatively impact performance. The purpose of this study is to characterize the prevalence and severity of hand injuries in National Football League (NFL) players. METHODS: A public online database was utilized to identify hand injuries in NFL players from 2009-2010 to 2019-2020. The primary outcome was to analyze the overall incidence of hand injuries (including wrist, metacarpus, finger, and thumb), injury type by each aforementioned anatomic location, and player position. Injury severity was evaluated based on percentage of injuries in which players returned to play (RTP), number of games missed before RTP, and the percentage of injuries resulting in the player being placed on injured reserve (IR). RESULTS: Of the 6,127 players included, 847 (13.8%) players sustained a hand injury, of which 24.8%, 34.3%, 17.9%, and 22.9% occurred at the wrist, metacarpus, finger, and thumb, respectively. Of the injured players, 97.4% returned to play following their injury, 14.8% were put on IR, and an average of 1.7 (SD 3.3) games were missed. Quarterbacks were the most likely to sustain hand injuries at all anatomic locations. Wrist injuries were associated with the lowest RTP rate (93.3%), the most players placed on injured reserve (28.6%), and the greatest number of games missed (mean 2.5, SD 4.2). CONCLUSION: Hand injuries decreased in prevalence by 65.6% over the 11 NFL seasons evaluated. This trend coincides with the implementation of several safety rules that relate to components of play involving the hands. Quarterbacks experienced the greatest prevalence and severity for all hand injuries. Wrist injuries represent the anatomic location associated with the greatest severity. These findings may be able to inform tailored injury prevention practices by position, and advocate for the further adoption of safety rules to protect players from further injury.

Treating post-traumatic osteomyelitis of a metacarpal fracture with the 'mini-masquelet' procedure.

Background: Post-traumatic osteomyelitis is a challenging complication after a fracture, requiring long-term treatment to prevent loss of function. One treatment strategy is the biphasic masquelet technique, focussing on both control of the infection and bone reconstruction. This technique is mainly used to treat defects of the long bones. Very little literature exists about the masquelet procedure for treatment of defects of smaller bones. We describe a case of post-traumatic osteomyelitis after a metacarpal fracture, treated with the 'mini-masquelet' technique. Patient case: A 23-year old woman was treated with the masquelet procedure for osteomyelitis and bone loss following a metacarpal IV fracture of her right hand. After 29 weeks, she had full range of motion of both the hand and fingers. Conclusion: The 'mini-masquelet' technique as a strategy to treat osteomyelitis and reconstruct bone loss after a metacarpal fracture, can reduce potential loss of function and loss of quality of life. This technique appears to be widely applicable for treatment of complex hand injuries and osteomyelitis of the hand.

METACARPAL FRACTURES TREATMENT: COMPARASION BETWEEN KIRSCHNER WIRE AND INTRAMEDULLARY SCREW.

Introduction: Metacarpal fractures are common and can be treated surgically using Kirschner wires (K-wires) or intramedullary fixation with compression screws (IMCS). Objectives: Analyze the postsurgical results from treating the metacarpal extra-articular fractures through the retrograde Kirschner wire technique, and compare it with the intramedullary compression screw fixation. Methods: Retrospective and quantitative studies were to analyze patients' medical records, and a postsurgical evaluation questionnaire was given to the patients, who were divided into K-wire and IMCS. Results: The period of immobilization with a splint took six weeks for the K-wire group and four weeks for the IMCS group. The average time for consolidation took, respectively, fifty-seven days and forty-seven days. The first group could restart their activities twenty-two days after the other, and the average force value of the treated hand, when compared with its contralateral, was 93.9% and 95.4%, respectively. Between the operated hand and its contralateral, there was a difference of 16° in the total measures of the metacarpophalangeal and interphalangeal joint's range of movement among the K-wire group and 5° among the IMCS group. Conclusion: The patients who participated in this study showed excellent results after surgery, and both treatments were proven to be safe and reliable. Evidence level III; Retrospective comparative study .

Introdução: Fraturas dos metacarpos são frequentes e podem ser tratadas de forma cirúrgica com os fios de Kirschner (FK) e Fixação Intramedular com Parafuso de Compressão (FIPC). Objetivo: Analisar os resultados pós-operatórios do tratamento das fraturas extra-articulares dos metacarpos pela técnica retrógrada com fios de Kirschner e comparar com a fixação intramedular utilizando parafuso de compressão. Métodos: Estudo retrospectivo, quantitativo, com análise de prontuários, utilizando questionários de avaliação pós-operatória em dez pacientes divididos em dois grupos: FIPC e FK. Resultados: O período de imobilização com tala nos grupos FK e FIPC foram de seis e quatro semanas respectivamente, já o tempo médio para consolidação foi de 57 e 47 dias respectivamente. O grupo FK retornou as atividades laborais após os FIPC. O valor médio de força na mão acometida comparada a contralateral foi de 93,9% no grupo FK, e no FIPC de 95,4%. Medidas da soma de amplitude de movimento das articulações metacarpofalangeanas e interfalangeanas no grupo FK obtiveram diferença média entre as mãos operada e a contralateral de 16°, já na FIPC observou-se 5°. Conclusão: Os pacientes estudados apresentaram excelentes resultados pós-operatórios e ambos os tratamentos provam ser seguros e confiáveis. Nível de evidência III; Estudo retrospectivo comparativo .

Metacarpal fractures treatment: comparasion between kirschner wire and intramedullary screw / Tratamento de fraturas metacarpais: comparação entre fios de kirschner e fixação intramedular

ABSTRACT Introduction: Metacarpal fractures are common and can be treated surgically using Kirschner wires (K-wires) or intramedullary fixation with compression screws (IMCS). Objectives: Analyze the postsurgical results from treating the metacarpal extra-articular fractures through the retrograde Kirschner wire technique, and compare it with the intramedullary compression screw fixation. Methods: Retrospective and quantitative studies were to analyze patients' medical records, and a postsurgical evaluation questionnaire was given to the patients, who were divided into K-wire and IMCS. Results: The period of immobilization with a splint took six weeks for the K-wire group and four weeks for the IMCS group. The average time for consolidation took, respectively, fifty-seven days and forty-seven days. The first group could restart their activities twenty-two days after the other, and the average force value of the treated hand, when compared with its contralateral, was 93.9% and 95.4%, respectively. Between the operated hand and its contralateral, there was a difference of 16° in the total measures of the metacarpophalangeal and interphalangeal joint's range of movement among the K-wire group and 5° among the IMCS group. Conclusion: The patients who participated in this study showed excellent results after surgery, and both treatments were proven to be safe and reliable. Evidence level III; Retrospective comparative study .

RESUMO Introdução: Fraturas dos metacarpos são frequentes e podem ser tratadas de forma cirúrgica com os fios de Kirschner (FK) e Fixação Intramedular com Parafuso de Compressão (FIPC). Objetivo: Analisar os resultados pós-operatórios do tratamento das fraturas extra-articulares dos metacarpos pela técnica retrógrada com fios de Kirschner e comparar com a fixação intramedular utilizando parafuso de compressão. Métodos: Estudo retrospectivo, quantitativo, com análise de prontuários, utilizando questionários de avaliação pós-operatória em dez pacientes divididos em dois grupos: FIPC e FK. Resultados: O período de imobilização com tala nos grupos FK e FIPC foram de seis e quatro semanas respectivamente, já o tempo médio para consolidação foi de 57 e 47 dias respectivamente. O grupo FK retornou as atividades laborais após os FIPC. O valor médio de força na mão acometida comparada a contralateral foi de 93,9% no grupo FK, e no FIPC de 95,4%. Medidas da soma de amplitude de movimento das articulações metacarpofalangeanas e interfalangeanas no grupo FK obtiveram diferença média entre as mãos operada e a contralateral de 16°, já na FIPC observou-se 5°. Conclusão: Os pacientes estudados apresentaram excelentes resultados pós-operatórios e ambos os tratamentos provam ser seguros e confiáveis. Nível de evidência III; Estudo retrospectivo comparativo .

Comparison of post-operative outcomes after open or closed surgical techniques to stabilize metacarpal and metatarsal fractures in dogs and cats.

BACKFROUND: Treatment options for metacarpal/metatarsal fractures include conservative and surgical management. The aim of this study is to determine whether there is any significant difference in healing and complication rates, between open and closed treatment. Medical records of dogs and cats with metacarpal/metatarsal fractures with complete follow-up were retrospectively reviewed. Patients were allocated in two groups: open or closed stabilization. Minor and major complications were recorded and compared. Fracture healing was classified as good, delayed and non-union, and it was statistically compared. RESULTS: Sixty-three patients (35 dogs and 28 cats) were included. Thirty-one were treated with an open approach and 32 by a closed stabilization. Regarding fracture healing a significantly higher proportion of delayed healing/non-union was found in the closed group (12/32 vs 2/31). Regarding postoperative complications, a significantly higher number of animals in the open group did not develop any complications (12/31 vs 3/32). A significantly higher proportion of minor complications were reported in the closed group (27/32 vs 12/31). However, a higher number of major complications was reported in the open group (7/31 vs 2/32) although this was not statistically significant. Fracture malalignment was significantly more prevalent in patients undergoing closed stabilization (11/32 vs 2/31). CONCLUSION: According to the results, better healing, fracture alignment and a lower complication rate are found when fractures are stabilised with an open technique. However, other factors such as configuration of the fracture, soft tissue involvement, patient´s character and client´s situation would also need to be taken into account in the decision of stabilization technique.

Biomechanical and Microstructural Properties of Subchondral Bone From Three Metacarpophalangeal Joint Sites in Thoroughbred Racehorses.

Fatigue-induced subchondral bone (SCB) injury is common in racehorses. Understanding how subchondral microstructure and microdamage influence mechanical properties is important for developing injury prevention strategies. Mechanical properties of the disto-palmar third metacarpal condyle (MCIII) correlate poorly with microstructure, and it is unknown whether the properties of other sites within the metacarpophalangeal (fetlock) joint are similarly complex. We aimed to investigate the mechanical and structural properties of equine SCB from specimens with minimal evidence of macroscopic disease. Three sites within the metacarpophalangeal joint were examined: the disto-palmar MCIII, disto-dorsal MCIII, and proximal sesamoid bone. Two regions of interest within the SCB were compared, a 2 mm superficial and an underlying 2 mm deep layer. Cartilage-bone specimens underwent micro-computed tomography, then cyclic compression for 100 cycles at 2 Hz. Disto-dorsal MCIII specimens were loaded to 30 MPa (n = 10), while disto-palmar MCIII (n = 10) and proximal sesamoid (n = 10) specimens were loaded to 40 MPa. Digital image correlation determined local strains. Specimens were stained with lead-uranyl acetate for volumetric microdamage quantification. The dorsal MCIII SCB had lower bone volume fraction (BVTV), bone mineral density (BMD), and stiffness compared to the palmar MCIII and sesamoid bone (p < 0.05). Superficial SCB had higher BVTV and lower BMD than deeper SCB (p < 0.05), except at the palmar MCIII site where there was no difference in BVTV between depths (p = 0.419). At all sites, the deep bone was stiffer (p < 0.001), although the superficial to deep gradient was smaller in the dorsal MCIII. Hysteresis (energy loss) was greater superficially in palmar MCIII and sesamoid (p < 0.001), but not dorsal MCIII specimens (p = 0.118). The stiffness increased with cyclic loading in total cartilage-bone specimens (p < 0.001), but not in superficial and deep layers of the bone, whereas hysteresis decreased with the cycle for all sites and layers (p < 0.001). Superficial equine SCB is uniformly less stiff than deeper bone despite non-uniform differences in bone density and damage levels. The more compliant superficial layer has an important role in energy dissipation, but whether this is a specific adaptation or a result of microdamage accumulation is not clear.

Investigating metacarpi of Hamdani sheep via different measurement and modelling methods: A methodological study.

The aim of the study was to perform the morphometric analyses on metacarpi of Hamdani sheep via different measurement methods and to compare the methods. Thus, metacarpal bones of 15 females and 15 males were used in the study. Measurements were taken from the measurement points determined on metacarpus via four methods, and their statistical analyses were performed. When both male and female metacarpal bones were examined in the De parameter in the comparison with the methods, it was observed that the four measurement methods were different from one another (p < 0.01). When DEM and DEL measurement parameters were examined in male metacarpus, the highest value was measured in ImageJ and the smallest value was measured in 3D Slicer software; however, it was found that the statistical difference was not significant when compared numerically (p > 0.05). As a result, while it was observed that the measurements made by using digital calliper measurements, photometric analysis, and 3D software were similar in some of the parameters but there was no statistically significant difference; whereas, Statistical difference was detected in some parameters.

Comparative morphological study of the male and female metacarpal and metatarsal bones of the dromedary camel with special reference to the blood vasculature.

Background: It is vital to understand the gross anatomy and dimensions of the metacarpal and metatarsal bones in camels in order for veterinarians to identify fraud cases between males and females by carefully distinguishing between them. Aim: It is to make comparisons of the morphological characteristics and measurements of the metacarpus and metatarsus bones of male and female camels. Methods: Forty metacarpus and metatarsus of adult camels of both sexes were collected from a typical Burydah slaughterhouse in KSA. The bones were treated according to the established methods of boiling, drying, and bleaching to study morphology. The measurement of the bones in this study has been taken by using digital vernier calipers. Results: The metacarpus and metatarsus consisted of two large and two small bones. The large metacarpal and metatarsal bones consisted of fused III and IV. Except for the distal side in which the two bones diverge more from each other. The metacarpal bone is similar to the metatarsus, except that it is smaller in measurement majority. The small Mc-Mt II and Mc-Mt V were smaller and present on the palmo-lateral or planto-lateral aspect of the large bones, respectively. The length of the metacarpus and metatarsus is almost equal nearly in camels unlike the rest of the animals as well as the metacarpus bone was unlike the metatarsus in form and measurements generally. Conclusion: The large metacarpus and metatarsus bones are distinguished by the fusion of the third and fourth bones along the length of the bone. Except for the distal side in which the two bones diverge more from each other like the rest of the animals. The morphologically characterized majority of the metacarpal bone was similar to the metatarsus, except that it was proximal extremity, cross-section, and measurement.

Closed reduction of severely angulated Rockwood and Wilkins' type C thumb Metacarpal Base fractures in children: case series.

BACKGROUND: Management of severely angulated Rockwood and Wilkins' type C (RW-C) thumb metacarpal base fractures in children is challenging. We report experiences of percutaneous leverage reduction and dual antegrade crossing Kirschner (DACK) wire fixation in these fractures, aiming to assess the results using our reduction technique. METHODS: From October 2011 to September 2015, A total of 17 patients with severely angulated RW-C thumb metacarpal base fractures were treated at our hospital. The injured arm, including the entire first ray, was immobilized with a thumb-spica cast for 4-6 weeks and evaluated radiologically and clinically. Percutaneous leverage reduction and DACK wire fixation were successfully performed for 17 patients. No patients were treated with open reduction. 16 patients were followed up for a mean of 32 months (range 24-41 months). The results were assessed using the modified Mayo score. The level of significance was set to be p < 0.05. RESULTS: The patients included 9 girls (56.2%) and 7 boys (43.8%), with an average age of 10.8 years (range 7.5 to 14.0 years). Percutaneous leverage reduction and DACK wire fixation were successfully performed within an average total surgery time of 20 min (range 12-32 min). Bone union was achieved in all patients within a mean time of 4.2 weeks (range 4-6 weeks). The average angulation (preoperation: 50.5° (range 40.8°-67.0°) vs postoperation: 5.0° (range 0.0°-7.0°)) significantly changed from pre to post-surgery (P < 0.05). The clinical outcomes were evaluated by the modified Mayo score: 15 patients had an excellent outcome, and one patient had a good outcome. Cosmetic results were described as good and satisfactory by all patients. There were no refractures and no incidences of nonunion, growth arrest in the proximal epiphysis. Only one patient suffered from a superficial infection, which was resolved after the removal of the k-wires and the administration of oral antibiotics. CONCLUSION: Our percutaneous leverage technique with DACK wire fixation can be successfully used to treat these fractures. This technique is simple to learn and minimally invasive, and the results are satisfactory. It may be an appropriate choice for the treatment of irreducible RW-C fractures.

Osteosynthesis of Fractures of the Metacarpal Neck with Self-Compressing Screw - Preliminary Analysis of 21 Cases.

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 5 th , 3 rd , and 2 nd (n = 19, 1 and 1). Surgical indications were neck-shaft diaphysis of the metacarpal > 30° for the 2 nd and 3 rd metacarpals and > 40° for the 5 th 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 > 240° 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.

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.

Return to Sport After Metacarpal and Phalangeal Fractures: A Systematic Review and Evidence Appraisal.

BACKGROUND: Fractures of the metacarpals and phalanges account for more than half of all upper extremity fractures sustained by competitive athletes. PURPOSE: To determine which management strategy is best for expediting return to preinjury levels of competition in adult athletes with metacarpal and/or phalangeal fractures. STUDY DESIGN: Systematic review; Level of evidence, 4. METHODS: A methodology compliant with PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) was used. A custom search strategy was designed and applied to MEDLINE and In-Process, Embase, EMCARE, and CINAHL. RESULTS: Overall, 3135 records were identified, of which 8 met full inclusion criteria. All patients returned to preinjury levels of competition, at a mean of 30.6 days for phalangeal fractures and 21.9 days for metacarpal fractures. Meta-analysis demonstrated delayed return-to-sport time for operatively managed metacarpal fractures as compared with nonoperatively managed ones (28.5 vs 22.0 days). All studies were of fair or poor quality, and none were randomized. CONCLUSION: Optimal management strategies for athletes with metacarpal and phalangeal fractures remain equivocal. Injury, treatment, and sport-specific factors may confound results and preclude accurate estimation of optimal treatment strategies at present.

The 2nd Metacarpal Cortical Index as a Simple Screening Tool for Osteopenia.

BACKGROUND: Osteopenia is a known risk factor for sustaining skeletal fractures. Prevention of fragility fractures has obvious clinical and economic advantages, however screening all patients using a dual energy X-ray absorptiometry (DXA) is controversial not only because of the cost implications but also because it would potentially involve exposing a percentage of normal patients to unnecessary radiation. We wished to assess whether a simple hand X-ray measuring the 2nd metacarpal cortical index (2MCI) could be used as a simple screening tool for identifying patients with osteopenia. METHODS: We retrospectively collected the radiographic data of 206 patients who had a simple radiograph of the hand and a DXA scan within one year of each other from our picture archiving and communication system database. The 2MCI was calculated for all patients. As data was parametric, a Pearson's correlation was performed to assess association between Tscores and 2MCI. Further analysis involved the construction of receiver operating characteristic (ROC) curves to identify a 2MCI index, which would give the most appropriate sensitivity and specificity values for identifying the presence of osteopenia. RESULTS: A statistically significant and moderate correlation between DXA T-scores and 2MCI values was found (r=0.54, n=206, P<0.001). Further ROC curve analysis of normal and osteopenic subjects identified that a 2MCI of 41.5 had a sensitivity of 100% and specificity of 53% for detecting osteopenia. CONCLUSIONS: Our results support the use of the 2MCI as a simple screening tool for identifying patients with osteopenia.

Bone Morphology and Strength in the Mid-Diaphysis of the Humerus and Metacarpus in Dairy Calves Prior to Weaning.

Calf growth rate in relation to future milk production has been thoroughly studied; however, the observation of growth arrest lines in bones from heifers with humeral fractures has highlighted the need to understand bone growth in relation to calf growth. The aim of this study was to describe the relationship of peripheral quantitative computed tomography (pQCT)-derived measures of bone strength and morphology with gross measurements of size and growth in pre-weaning dairy calves. Liveweight, height, body length, girth and leg length were measured at one, six and twelve weeks of age. At these intervals, the mid-diaphysis of the metacarpus was also scanned in the live animal using pQCT. At six and twelve weeks old, a subset of calves were euthanised and the humerus was collected and scanned at the mid-diaphysis using pQCT. Differences in growth patterns were observed between the metacarpus and humerus over time. Weight was the best predictor for measures of periosteal circumference and stress strain index (R2 = 0.49-0.58) in the metacarpus, and also the best predictor for measures of stress strain index at all ages in the humerus (R2 = 0.94). The strong relationship with weight and bone measures emphasises the need for adequate preweaning nutrition for future bone growth.

Evaluación de medidas morfométricas de tendones y ligamentos metacarpales palmares por ultrasonografía en caballos criollos colombianos / Evaluation of morphometric measures of tendons and metacarpal ligaments by ultrasonography in Colombian creole horses

RESUMEN Objetivo. Determinar los parámetros morfométricos ultrasonográficos de los tendones y ligamentos metacarpales palmares de caballos criollos colombianos clínicamente sanos. Materiales y métodos. Treinta caballos criollos colombianos clínicamente sanos de 6.4 ± 2.5 años se evaluaron en diferentes zonas del departamento de Córdoba (Colombia). Se midieron las variables área transversal (cm2), ancho latero medial (ALM) (cm) y espesor dorso palmar (EDP) (cm) en las estructuras de la región metacarpiana en los dos miembros anteriores mediante ultrasonografía. Resultados. La ecografía reveló que el área transversal del ligamento suspensorio fue la estructura de mayor área en las regiones proximales (1A, 1B y 2A), tanto para la extremidad izquierda como para la derecha. Por otro lado, no hubo una diferencia significativa (p>0.05) entre la extremidad izquierda y derecha para las mediciones de las estructuras en cualquier zona, y no hubo una diferencia significativa entre los grupos de edades e índice de masa corporal (IMC) de los caballos. Conclusiones. Se obtuvieron valores de referencia para los tendones y ligamentos en la región metacarpiana palmar en equinos proporcionando una guía de referencia cuando se sospechan condiciones patológicas metacarpo en equinos.

ABSTRACT Objective. To determine the ultrasonographic morphometric parameters of the palmar metacarpal tendons and ligaments of clinically healthy Colombian creole horses. Materials and methods. Thirty clinically healthy Colombian creole horses of 6.4 ± 2.5 years were evaluated in different areas of the department of Córdoba (Colombia). The variables cross-sectional area (cm2), medial lateral width (ALM) (cm) and dorsal palmar thickness (EDP) (cm) in the structures of the metacarpal region in the two anterior members were measured by means of ultrasound. Results. Ultrasonography revealed that the transverse area of the suspensory ligament was the structure with the largest area in the proximal regions (1A, 1B and 2A), for both the left and right limbs. On the other hand, there was no significant difference (P> 0.05) between left and right limb for measurements of structures in any area, and there was no significant difference between age groups and body mass index (BMI) of horses. Conclusions. Reference values for tendons and ligaments in the palmar metacarpal region were obtained in equines providing a reference guide when metacarpal pathological conditions in equines are suspected.

Abundant osteoclasts in the subchondral bone of the juvenile Thoroughbred metacarpus suggest an important role in joint maturation.

BACKGROUND: The administration of bisphosphonate medications, which target osteoclastic-bone remodelling, to juvenile and adult racehorses is a matter of debate owing to concerns that these molecules remain bound to the bone-mineralised matrix and may interfere with subsequent bone growth, adaptation to exercise and healing of bone microdamage in equine athletes. Osteoclasts participate in endochondral ossification, subchondral bone remodelling and bone repair. There is a knowledge gap on the role of equine osteoclast biology in the growth and maturation of joint surfaces and this information is important to inform judicious bisphosphonate use. OBJECTIVES: Measure and compare the osteoclast density in the subchondral bone of Thoroughbred (TB) distal third metacarpi (McIII) at different sites, varying depths from the articular surface and with age (0-84 months). STUDY DESIGN: Ex vivo cadaveric study. METHODS: McIIIs from foals, yearlings and adults were collected, fixed in formaldehyde and stored at 4°C. Sections were cut from the lateral hemi-metacarpus, stained and scored for cartilage degeneration. Osteoclasts were counted on immunohistochemically (Cathepsin K) stained sections. Osteoclast density was compared in regions of interest (ROIs-the sagittal ridge, axial and abaxial condyle) and also at two depths (0-3 mm and 3-6 mm) into the subchondral bone below the osteochondral junction. RESULTS: The osteoclast density was consistently highest in the subchondral cortical bone plate (0-3 mm) when compared with the deeper trabecular bone in all age groups. Furthermore, the osteoclast density was significantly higher in juvenile Thoroughbreds (foals and yearlings) within both sites in the subchondral bone when compared with adults. MAIN LIMITATIONS: The number of specimens available for study was restricted. CONCLUSIONS: Osteoclasts are important in normal McIII epiphyseal and articular surface maturation and have a propensity to localise at the osteochondral junction and subchondral cortical bone plate zone in juvenile Thoroughbreds.

The relationship between microstructure, stiffness and compressive fatigue life of equine subchondral bone.

Subchondral bone injuries often precede articular cartilage damage in osteoarthritis and are common in thoroughbred racehorses due to the accumulation of fatigue damage from high speed racing and training. Thus, racehorses provide a model to investigate the role of subchondral bone in joint disease. We assessed the association of horse and racing related factors and micro-CT based micromorphology of three separate subchondral bone layers with the initial stiffness and compressive fatigue life of bone plugs. Furthermore, we investigated three different definitions of fatigue failure of subchondral bone during compressive fatigue testing. Initial stiffness was 2,362 ±â€¯443 MPa (mean ±â€¯standard deviation). Median compressive fatigue life during cyclic loading to -78 MPa was 16,879 (range 210 to 57,064). Subchondral bone stiffness increased over a median of 24% (range 3%-42%) of fatigue life to a maximum of 3,614 ±â€¯635 MPa. Compressive fatigue life was positively associated with bone volume fraction in the deeper layers of subchondral bone, maximal stiffness, and the number of cycles to maximal stiffness. Initial stiffness was positively associated with tissue mineral density in the deeper layers and bone volume fraction in the superficial layer. Most specimens with a fatigue life of less than 5,500 cycles fractured grossly before reaching 30% reduction of maximal stiffness. Cycles to 10% reduction of maximal stiffness correlated strongly with cycles to lowest recorded stiffness at gross fracture and thus is a valid alternative failure definition for compressive fatigue testing of subchondral bone. Our results show that subchondral bone sclerosis as a result of high speed exercise and measured as bone volume fraction is positively associated with compressive fatigue life and thus has a protective effect on subchondral bone. Further research is required to reconcile this finding with the common collocation of fatigue damage in sclerotic subchondral bone of racehorses.

[Biomechanical comparison of six different fixation techniques for treatment of metacarpal neck fractures]. / Biomechanischer Vergleich sechs verschiedener Fixationstechniken zur Versorgung von Halsfrakturen der Metakarpale.

PURPOSE: The purpose of this study was to evaluate the primary stability of commonly used fixation techniques for metacarpal neck fractures and to compare it with that of an innovative osteosynthesis device: IlluminOss™, the photodynamic bone stabilization system™. MATERIAL AND METHODS: Metacarpal neck fractures were created on the second to fifth metacarpal bones of 24 freshly frozen human cadavers using a band saw. Specimens were randomly assigned to one of six groups and treated with (1) K-wire fixation, (2) dorsal plating, (3) external fixation, (4) cross-threaded K­wire fixation, (5) IlluminOss™ and (6) locked IlluminOss™. In each group 16 specimens each underwent either monocyclic or polycyclic loading protocols. RESULTS: During monocyclic loading none of the specimens failed prior to a maximum deformation of 3 mm. With intramedullary K­wire fixation the mean loads were significantly lower than those of the other techniques. Mean loads causing 2 mm deformation with external fixation were significantly lower than those with dorsal plate osteosynthesis. The mean linear stiffness of the K­wire osteosynthesis was significantly lower than for the other fixation techniques and all methods of external fixation were significantly lower than dorsal plates. There were no significant differences with respect to the linear stiffness between the groups with dorsal plates, fragment fixation system (FFS), IlluminOss™ and locked IlluminOss™. During polycyclic testing the loss of resistance in dorsal plate osteosynthesis was significantly lower than with K­wire and IlluminOss™ fixation. No significant differences in loss of resistance could be shown between dorsal plate osteosynthesis, external fixation, FFS and locked IlluminOss™. CONCLUSION: In summary, IlluminOss™ can be used as an intramedullary stabilization system for treatment of metacarpal neck fractures. In combination with locking screws the biomechanical characteristics of IlluminOss™ are comparable to the other fixation techniques.

Differences in third metacarpal trabecular microarchitecture between the parasagittal groove and condyle at birth and in adult racehorses.

BACKGROUND: The aetiology of equine metacarpal condylar fractures is not completely understood and a developmental cause has been postulated. OBJECTIVES: To investigate the subchondral bone trabecular microarchitecture of the lateral parasagittal groove and condyle in equine neonates and its adaptation with maturation and athletic activity. STUDY DESIGN: Ex vivo observational study. METHODS: Distal metacarpi of neonates, yearlings and adult racehorses (n = 24) were harvested. Dorsal and palmar frontal histological sections, containing the lateral parasagittal groove and condyle, were studied. The sections were digitalised and subchondral trabecular bone quantity and quality parameters and trabecular orientation in the frontal plane were measured. RESULTS: Trabecular spacing and length were greater (P = 0.004 and P = 0.0005 respectively) whereas bone fraction, trabecular number and connectivity were all lower (P = 0.0004, P = 0.0001 and P = 0.001 respectively) in the lateral parasagittal groove compared with the condyle in neonatal foals. Trabecular thickness and bone fraction increased with age in racehorses and trabecular spacing decreased. The predominant trabecular orientation had a consistent pattern in neonates and it changed with maturity and the cumulative effect of racing at all the ROIs except for the palmar lateral parasagittal groove that retained a more 'immature' pattern. MAIN LIMITATIONS: Samples were investigated in 2D. 3D processing could have provided more information. CONCLUSIONS: Already at birth there are striking differences in the subchondral bone trabecular microarchitecture between the lateral parasagittal groove and condyle in foals. Adaptation of trabeculae is confirmed with maturity in racehorses, with the greatest adaptation measured in bone quantity parameters. The trabecular orientation had a unique and more immature orientation pattern in the lateral palmar parasagittal grooves in adult racehorses and may reflect a weaker structure at this site.