CLASSIFYING RADIUS FRACTURES WITH X-RAY AND TOMOGRAPHY IMAGING

Introduction: This study evaluated the interobserver reliability of plain radiograpy versus computed tomography (CT) for the Universal and AO classification systems for distal radius fractures. Patients and methods: Five observers classified 21 sets of distal radius fractures using plain radiographs and CT independently. Kappa statistics were used to establish a relative level of agreement between observers for both readings. Results: Interobserver agreement was rated as moderate for the Universal classification and poor for the AO classification. Reducing the AO system to 9 categories and to its three main types reliability was raised to a ""moderate"" level. No difference was found for interobserver reliability between the Universal classification using plain radiographs and the Universal classification using computed tomography. Interobserver reliability of the AO classification system using plain radiographs was significantly higher than the interobserver reliability of the AO classification system using only computed tomography. Conclusion: From these data, we conclude that classification of distal radius fractures using CT scanning without plain radiographs is not beneficial.

Comparison of different radiography systems in an experimental study for detection of forearm fractures and evaluation of the Müller-AO and Frykman classification for distal radius fractures

OBJECTIVES: We sought to compare the diagnostic performance of screen-film radiography, storage-phosphor radiography, and a flat-panel detector system in detecting forearm fractures and to classify distal radius fractures according to the Müller-AO and Frykman classifications compared with the true extent, depicted by anatomic preparation. MATERIALS AND METHODS: A total of 71 cadaver arms were fractured in a material testing machine creating different fractures of the radius and ulna as well as of the carpal bones. Radiographs of the complete forearm were evaluated by 3 radiologists, and anatomic preparation was used as standard of reference in a receiver operating curve analysis. RESULTS: The highest diagnostic performance was obtained for the detection of distal radius fractures with area under the receiver operating curve (AUC) values of 0.959 for screen-film radiography, 0.966 for storage-phosphor radiography, and 0.971 for the flat-panel detector system (P > 0.05). Exact classification was slightly better for the Frykman (kappa values of 0.457-0.478) compared with the Müller-AO classification (kappa values of 0.404-0.447), but agreement can be considered as moderate for both classifications. CONCLUSIONS: The 3 imaging systems showed a comparable diagnostic performance in detecting forearm fractures. A high diagnostic performance was demonstrated for distal radius fractures and conventional radiography can be routinely performed for fracture detection. However, compared with anatomic preparation, depiction of the true extent of distal radius fractures was limited and the severity of distal radius fractures tends to be underestimated.

Reference values for digital X-ray radiogrammetry parameters in children and adolescents in comparison to estimates in patients with distal radius fractures.

The first objective of this study was to determine normative digital X-ray radiogrammetry (DXR) values, based on original digital images, in a pediatric population (aged 6-18 years). The second aim was to compare these reference data with patients suffering from distal radius fractures, whereas both cohorts originated from the same geographical region and were evaluated using the same technical parameters as well as inclusion and exclusion criteria. DXR-BMD and DXR-MCI of the metacarpal bones II-IV were assessed on standardized digital hand radiographs, without printing or scanning procedures. DXR parameters were estimated separately by gender and among six age groups; values in the fracture group were compared to age- and gender-matched normative data using Student's t tests and Z scores. In the reference cohort (150 boys, 138 girls), gender differences were found in bone mineral density (DXR-BMD), with higher values for girls from 11 to 14 years and for boys from 15 to 18 years (p < 0.05). Girls had higher normative metacarpal index (DXR-MCI) values than boys, with significant differences at 11-14 years (p < 0.05). In the case-control investigation, the fracture group (95 boys, 69 girls) presented lower DXR-BMD at 15-18 years in boys and 13-16 years in girls vs. the reference cohort (p < 0.05); DXR-MCI was lower at 11-18 years in boys and 11-16 years in girls (p < 0.05). Mean Z scores in the fracture group for DXR-BMD were -0.42 (boys) and -0.46 (girls), and for DXR-MCI were -0.51 (boys) and -0.53 (girls). These findings indicate that the fully digital DXR technique can be accurately applied in pediatric populations ≥ 6 years of age. The lower DXR-BMD and DXR-MCI values in the fracture group suggest promising early identification of individuals with increased fracture risk, without the need for additional radiation exposure, enabling the initiation of prevention strategies to possibly reduce the incidence of osteoporosis later in life.

Effect of cyclic pneumatic soft tissue compression on simulated distal radius fractures

We investigated the effect of pneumatic pressure applied to the proximal musculature of the sheep foreleg on load at the site of a transverse osteotomy of the distal radius. The distal radii of 10 fresh sheep foreleg specimens were osteotomized and a pressure sensor was inserted between the two bone fragments. An inflatable cuff, connected to a second pressure sensor, was positioned around the proximal forelimb musculature and the leg then was immobilized in a plaster cast. The inflatable cuff was inflated and deflated repeatedly to various pressures. Measurements of the cuff pressure and corresponding change in pressure at the osteotomy site were recorded. The results indicated that application of pneumatic pressure to the proximal foreleg musculature produced a corresponding increase in load at the osteotomy site. For the cuff pressures tested (109.8-238.4 mm Hg), there was a linear correlation with the load at the osteotomy site with a gradient of 12 mm Hg/N. It is conceivable, based on the results of this study, that a technique could be developed to provide dynamic loading to accelerate fracture healing in the upper limb of humans.

The Use of Radiostereometric Analysis in Fractures of the Distal Radius: From Phantom Models to Clinical Application

Radiostereometric analysis (RSA) is a highly accurate method for the measurement of in vivo micromotion of orthopaedic implants. Validation of the RSA method is a prerequisite for performing clinical RSA studies. Only a limited number of studies have utilised the RSA method in the evaluation of migration and inducible micromotion during fracture healing. Volar plate fixation of distal radial fractures has increased in popularity. There is still very little prospective randomised evidence supporting the use of these implants over other treatments. The aim of this study was to investigate the precision, accuracy, and feasibility of using RSA in the evaluation of healing in distal radius fractures treated with a volar fixed-angle plate. A physical phantom model was used to validate the RSA method for simple distal radius fractures. A computer simulation model was then used to validate the RSA method for more complex interfragmentary motion in intra-articular fractures. A separate pre-clinical investigation was performed in order to evaluate the possibility of using novel resorbable markers for RSA. Based on the validation studies, a prospective RSA cohort study of fifteen patients with plated AO type-C distal radius fractures with a 1-year follow-up was performed. RSA was shown to be highly accurate and precise in the measurement of fracture micromotion using both physical and computer simulated models of distal radius fractures. Resorbable RSA markers demonstrated potential for use in RSA. The RSA method was found to have a high clinical precision. The fractures underwent significant translational and rotational migration during the first two weeks after surgery, but not thereafter. Maximal grip caused significant translational and rotational interfragmentary micromotion. This inducible micromotion was detectable up to eighteen weeks, even after the achievement of radiographic union. The application of RSA in the measurement of fracture fragment migration and inducible interfragmentary micromotion in AO type-C distal radius fractures is feasible but technically demanding. RSA may be a unique tool in defining the progress of fracture union.

The AO comprehensive classification of pediatric long-bone fractures: a web-based multicenter agreement study.

The first AO comprehensive pediatric long-bone fracture classification system has been proposed following a structured path of development and validation with experienced pediatric surgeons. A Web-based multicenter agreement study involving 70 surgeons in 15 clinics and 5 countries was conducted to assess the reliability and accuracy of this classification when used by a wide range of surgeons with various levels of experience. Training was provided at each clinic before the session. Using the Internet, participants could log in at any time and classify 275 supracondylar, radius, and tibia fractures at their own pace. The fracture diagnosis was made following the hierarchy of the classification system using both clinical terminology and codes. kappa coefficients for the single-surgeon diagnosis of epiphyseal, metaphyseal, or diaphyseal fracture type were 0.66, 0.80, and 0.91, respectively. Median accuracy estimates for each bone and type were all greater than 80%. Depending on their experience and specialization, surgeons greatly varied in their ability to classify fractures. Pediatric training and at least 2 years of experience were associated with significant improvement in reliability and accuracy. Kappa coefficients for diagnosis of specific child patterns were 0.51, 0.63, and 0.48 for epiphyseal, metaphyseal, and diaphyseal fractures, respectively. Identified reasons for coding discrepancies were related to different understandings of terminology and definitions, as well as poor quality radiographic images. Results supported some minor adjustments in the coding of fracture type and child patterns. This classification system received wide acceptance and support among the surgeons involved. As long as appropriate training could be performed, the system classification was reliable, especially among surgeons with a minimum of 2 years of clinical experience. We encourage broad-based consultation between surgeons' international societies and the use of this classification system in the context of clinical practice as well as prospectively for clinical studies.

Effect of bovine bone morphogenetic proteins on radius fracture healing in rabbits

OBJETIVO: Investigar a influência de Proteínas Morfogenéticas Ósseas de origem bovina (bBMPs) ligadas a hidroxiapatita mais colágeno na consolidação de fraturas instáveis do rádio. MÉTODOS: em 15 coelhos com aproximadamente 5,5 meses de idade e peso médio de 3,5kg foi realizada uma fratura transversa na porção média da diáfise do rádio de ambos os membros. Na fratura do rádio direito foi aplicada mistura de bBMPs ligadas à hidroxiapatita (bBMP-HA) e colágeno bovino como aglutinante e na do rádio esquerdo, considerada controle, nenhum tratamento foi usado. Os coelhos (cinco por período) foram submetidos à eutanásia aos 30, 60 e 90 dias após a cirurgia para realização do processamento histológico e análise microscópica. RESULTADOS: A análise histológica descritiva revelou que a consolidação foi similar para os membros tratado e controle. Pela análise histomorfométrica, a área de novo osso foi em média 867442,16 mm², 938743.00 mm² e 779621,06 mm² para os membros controles e 841118,47 mm², 788038,76mm² e 618587,24 mm² para os membros tratados, aos 30, 60 e 90 dias, respectivamente. Desta forma, aos 60 dias de pós-operatório a área de novo osso foi 12.17% maior no membro tratado com bBMP-HA/colágeno em relação ao membro controle (p<0.05, teste de Tukey). em ambos os membros a área de novo osso aumentou durante o período experimental até a total consolidação da fratura. CONCLUSÃO: Baseado nos resultados obtidos foi possível concluir que a mistura de bBMP-HA/colágeno induziu pequena, porém significante melhora na consolidação da fratura.

Ligament origins are preserved in distal radial intraarticular two-part fractures: a computed tomography-based study

Background Operative fixation of intraarticular distal radius fractures is increasingly common. A greater understanding of fracture patterns will aid surgical fixation strategy. Previous studies have suggested that ligamentous insertions may less commonly be involved, but these have included heterogeneous groups of fractures and have not addressed Lister's tubercle. Purpose We hypothesize that fracture lines of distal radial intraarticular 2-part fractures have reproducible patterns. They propagate through the cortical bone between ligament origins and do not involve Lister's tubercle. Methods Axial CT scans of two-part intraarticular distal radius fractures were assessed independently by two examiners. The fractures were mapped onto a grid and the cortical breaches expressed as a percentile of the total radial width or length. The cortical breaches were compared with the ligamentous insertions on the distal and Lister's tubercle. Associated injuries were also documented. Results The cortical breaches occurred between the ligamentous insertions in 85%. Lister's tubercle was not involved in 95% of the fractures. Three major fracture patterns emerged: radial styloid, dorsal, and volar. Each major pattern had two subtypes. Associated injuries were common. Scapholunate dissociation was associated with all types, not just the radial styloid fracture pattern. Conclusions The fracture patterns of two-part intraarticular fractures mostly involved the interligamentous zones. Three major groups were identified: dorsal, volar, and radial styloid. Lister's tubercle was preserved with fractures tending to propagate radial or ulnar to this structure. We suggest conceptualizing fracture fragments as osseo-ligamentous units to aid prediction of fracture patterns and associated injury. Study Design Diagnostic III Level of Evidence 3.

Concordancia interobservador entre ortopedistas de urgencias y cirujanos de codo en fracturas de cúpula radial

El trauma de codo y la fractura de cúpula radial resultan ser un motivo de consulta frecuente en nuestro medio. Es común en nuestro medio que a pesar de tener radiografías de codo en las que se evidencia fractura de cúpula radial se solicite un TAC de codo. Consideramos que el TAC es una herramienta útil en algunos casos de fracturas de la cúpula radial, es decir, no se debe tomar de forma rutinaria el TAC de codo en los pacientes con fracturas de cúpula radial como es usual en nuestro medio. Existen pocos estudios que comparan la concordancia inter observador de las clasificaciones utilizadas para las fracturas de cúpula radial, pero, no existe en la literatura mundial un estudio que evalué las diferencias entre la clasificación de la fractura en base a radiografías y tomografía entre un grupo ortopedistas traumatólogos y sub-especialistas de miembro superior. La realización de este estudio permite elaborar guías de manejo de pacientes con fractura de cúpula radial en la que se racionalizara el uso del TAC de codo.

¿La tomografía de codo cambia la conducta tomada previamente con radiografía en fracturas de cúpula radial? un estudio de concordancia

Las fracturas de la cúpula radial corresponden a un tercio de todas las fracturas del codo en adultos (1), por lo que se toman radiografías o tomografías, sin embargo no existe literatura que soporte la realización de la tomografía como estudio complementario, por lo que preguntamos ¿La tomografía de codo cambia la conducta tomada previamente con radiografía en fracturas de cúpula radial? Se propone un estudio de concordancia, donde se evalúan las radiografías y tomografías por parte de dos cirujanos de codo, de pacientes con diagnóstico de fractura de cúpula radial valorados en urgencias de dos hospitales de tercer nivel de Bogotá desde enero 2011 a enero 2013. Se revisaron 116 historias, 99 cumplieron los criterios, las radiografías fueron revisadas por dos ortopedistas de codo quienes realizaron clasificación de Mason obteniendo un κ 1 (p˂ 0,00), propuesta de tratamiento postradiografía κ 0,934 (p˂ 0,000 IC95% 0.85, 1). Tratamiento post-tomografía de codo κ 0.949 (p˂ 0,00 IC95% 0.867,1). Concordancia intra-ortopedista de la conducta pre y post-tomografía hay cambio en la conducta del ortopedista 1 en 32.6% (κ 0.674 p˂ 0,00 IC95% 0.52, 0.818) y del ortopedista 2 en 36% (κ 0.64 p˂ 0,00 IC95% 0.452, 0.792). Se dividieron los pacientes en Mason I, II, III con concordancia considerable en los pacientes Mason I y III, mientras que en Mason II fue una concordancia aceptable lo que significa que el uso de tomografía de codo cambia la conducta en general pero sobretodo en pacientes clasificados Masson II.

Concordancia en el tratamiento de fracturas de radio distal basado en el estudio de radiografía y tomografía

Introducción: La utilidad de la tomografía computarizada como prueba de rutina en la toma de decisiones para las fracturas de radio distal no ha sido bien establecida. Metodología: Estudio de concordancia intra e interobservador en el tratamiento de fracturas de radio distal Fernández V. Se realizaron dos visitas, con intervalo de 2 semanas entre ellas a 15 ortopedistas de trauma quienes evaluaron 22 radiografías de muñeca y sus respectivas tomografías con fracturas de radio distal Fernández V, determinaron para cada caso la mejor opción de tratamiento. Se utilizó el coeficiente Kappa para evaluar la concordancia intra e interobservador para el plan de tratamiento propuesto y se analizaron los resultados según la interpretación de este coeficiente según Landis y Koch. Resultados: La concordancia entre radiografía y tomografía fue moderada kappa 0,47 – 0,51 en las dos evaluaciones respectivamente, manteniéndose el cambio de tratamiento entre 24,9% y 26,7% (p‹0,001). La concordancia observada intraobservador para radiografía y tomografía evaluadas de manera individual fue buena (72,1% y 64,2% respectivamente) evidenciándose cambio en la decisión de tratamiento hasta en el 35,8% de las evaluaciones (p‹0,001); se determinó concordancia observada muy buena en los casos a los que se propuso manejo abierto. No se identificó influencia de la edad en la decisión de tratamiento. Conclusiones: Existe buena concordancia entre radiografía simple y tomografía en fracturas de radio distal Fernández V en cuanto a la decisión de tratamiento, siendo alta la concordancia en los casos en los que se decide manejo abierto.

Fractura de radio distal como predictor de fractura de cadera en mayores de 65 años de un hospital universitario de alta complejidad en Bogotá

La osteoporosis es una de las condiciones patológicas en mayor crecimiento a medida que la población de tercera edad aumenta, esto se traduce en fracturas por fragilidad como lo son las fracturas de radio distal y las fracturas de cadera, actualmente no se cuentas con datos de la población a estudio que correlacione este tipo de fracturas. Es un estudio retrospectivo de casos y controles donde se obtuvo un grupo de pacientes con fractura de cadera que consultaron a un hospital universitario de alta complejidad en la ciudad de Bogotá, se evaluó la presencia de antecedente de fractura de radio distal y se comparó con un grupo control de trauma en cadera. Se obtuvo un total de 325 casos (72,5%) y 123 (25%) controles. El promedio de edad fue de 81 años, el 70% de los pacientes en ambos grupos correspondió a mujeres. No hubo diferencia en cuanto a la prevalencia de tabaquismo, hipertensión arterial o diabetes en los grupos. No se encontraron diferencias significativas en cuanto a niveles de glicemia, calcio, vitamina D. La presencia de antecedente de fractura de radio distal en grupo con fractura de cadera fue del 7,1% encontrando un OR de 3,91 IC 95%(1,17– 13,10). La presencia de fractura de radio distal como antecedente es un predictor para la fractura de cadera en pacientes mayores. Se necesitan más estudios que correlacionen otras variables que pueden influir en la asociación para fractura de cadera y radio, para así identificar una población específica que se beneficie de un tratamiento temprano.

Estudo mecânico da estabilidade dorsal da osteossíntese intramedular associada à fixação externa (método de Ulson)

OBJETIVO: Avaliar o método de Ulson de fixação intramedular associado à fixação externa variando a altura do travamento externo dos fios de Kirschner e sem fixação externa. MÉTODO: Foram utilizadas 18 tíbias de porcos, sendo realizada osteotomia transversal na região da tuberosidade e introduzidos dois fios de Kirschner intramedulares em cada peça, em três diferentes padrões de montagem: grupo I - travamento com minifixador externo com 3,0cm de altura; grupo II - travamento com 4,5cm de altura; grupo III: sem travamento externo. Realizaram-se ensaios mecânicos de cisalhamento, obtendo-se: carga máxima, limite de proporcionalidade e coeficiente de rigidez. RESULTADOS: Não foram encontradas diferenças significativas de carga máxima e limite de proporcionalidade entre os grupos; o grupo II apresentou maior coeficiente de rigidez. CONCLUSÃO: A altura do travamento dos fios de Kirschner no método de Ulson, dentro dos limites avaliados, não prejudicou a estabilidade do sistema de fixação da fratura.

Comparison between polyurethanes containing castor oil (Soft Segment) and cancellous bone autograft in the treatment of segmental bone defect induced in rabbits

The aim of this study is to compare polyurethanes containing castor oil (soft segment) in granular form compared to cancellous bone autograft applied to a segmental bone defect. Norfolk adult female rabbits - approximately 13 months of age with a mean body weight of 4.5 kg - are used. In both radial diaphyses, 1 cm osteoperiosteal segmental defects are created. The defect in the left radius is filled with the castor-oil-based polyurethane, and the right one, filled with cancellous bone autograft, collected from the left proximal humerus. The rabbits are euthanazed at 15, 30, 60, and 120 days postsurgery (5 animals/ period), for histological analyses. By radiographic analyses, at these time points, the bone regeneration is more evident and accelerated in the bone defects treated with the cancellous bone autograft. At 120 days postsurgery, the segmental bone defects treated with the cancellous bone autograft are totally reconstituted and remodeled, while the bone defects treated with polyurethane polymer have bone formation of 79%. Histological study shows that the polyurethane acts as a space filler, minimizing the local production of fibrous tissue. No granule degradation, resorption or any inflammatory reaction is detected. Thus, it is possible to conclude that the castor-oil-plant-based polyurethane - in the granule presentation - is biocompatible and osteointegrated, but does not show the same bone regeneration capacity as the cancellous bone autograft. © 2007 SAGE Publications.

Minimalinvasive Osteosynthese der distalen extraartikulären Radiusfraktur : XSCREW und DorsalNailPlate im biomechanischen Vergleich

Gegenstand der Arbeit: Die distale Radiusfraktur ist der häufigste Bruch des Menschen. Neben etablierten Verfahren wie der dorsalen und palmaren Plattenosteosynthese gibt es seit Kurzem neuartige minimalinvasive Osteosynthesesysteme. Gegenstand der vorliegenden Arbeit ist die Untersuchung der biomechanischen Stabilität von zwei neuartigen Implantaten für die distale extraartikuläre Radiusfraktur. rnMethodik: Es handelt sich einerseits um das System XSCREW (Zimmer, Freiburg i. Br., Deutschland), eine kanülierte Schraube, die über den Processus styloideus eingeführt wird und mit bis zu neun Bohrdrähten im Knochen fixiert werden kann. Das Vergleichsimplantat DorsalNailPlate (HandInnovations, Miami, Florida, USA) ist ein Hybrid aus einer dorsalen Platte und einem Marknagel. Beide Systeme wurden an 8 paarigen frischen unfixierten Leichenradii unter Axialbelastung bis 100 N und Torsionsbelastung bis 1,5 Nm getestet. Die A3-Fraktur wurde durch eine standardisierte Keilosteotomie simuliert. Das Biomaterial wurde prä- und postinterventionell sowie nach einem Dauerbelastungstest unter 1000 Zyklen in Rotation mit 0,5 Hz untersucht. Ein Versagenstest mit steigendem Drehmoment beendete das Experiment. rnErgebnisse: Die XSCREW erreichte eine Axialsteifigkeit von 136 N/mm und eine Torsionssteifigkeit von 0,16 Nm/°. Die DNP erzielte hingegen axial 70 N/mm und torsional 0,06 Nm/°. Der Unterschied zwischen beiden Verfahren war nur für die Torsion eindeutig statistisch auffällig (p=0,012), jedoch nicht für die Axialsteifigkeit (p=0,054). Die ursprüngliche Axial- und Torsionssteifigkeit wurde durch die XSCREW signifikant besser wiederhergestellt als durch die DNP (p=0,012). Beide Verfahren erzielten nach der Intervention signifikant niedrigere Steifigkeiten als die intakten Knochen (p=0,012). Ein Präparat der DNP-Gruppe und vier Präparate der XSCREW-Gruppe überstanden den Dauerbelastungstest. Das Drehmoment bei Versagen war mit der XSCREW höher als mit der DNP, der Unterschied zwischen den Verfahren war signifikant (p=0,043). Die Schwachstellen beider Systeme lagen vorwiegend in der proximalen Verankerung im Knochen. Kirschner-Drähte bzw. Verriegelungsschrauben führten unter andauernder Belastung zu einer Spaltung der Kortikalis im Schaftbereich. Bedingt durch die Ausrichtung der distalen Verriegelungen können mit beiden Implantaten Schäden an der radiocarpalen bzw. radioulnaren Gelenkfläche entstehen. rnZusammenfassung: Die XSCREW ermöglicht insgesamt eine höhere mechanische Stabilität als die DNP. Beide Verfahren sind jedoch einer winkelstabilen palmaren Plattenosteosynthese insbesondere unter rotatorischer Dauerbelastung unterlegen und erreichen nicht die Stabilität eines anderen neuartigen minimalinvasiven Systems.