Distal Radioulnar Joint Instability.

SUMMARY: The distal radioulnar joint (DRUJ) is vital to the stability and function of the wrist and forearm. The osseous morphology is variable and provides little stability. A complex of confluent soft tissues is the primary stabilizer; however, the contribution of each component has yet to be elucidated. It has become increasingly clear that the anatomic fixation of distal radius fractures restores DRUJ stability, obviating the need for additional DRUJ stabilization. This review will describe the anatomy and biomechanics of the DRUJ and discuss injury patterns, treatments, and clinical results.

It is safe to use the ulnar length difference to correct the radial length difference in the 3D-planning process of a radius osteotomy in patients with a distal radius malunion.

BACKGROUND: A corrective radius osteotomy is often performed in patients with a symptomatic distal radius malunion. In 3D-planned osteotomies, the unaffected radius is mirrored over the malunited radius after adjusting for left-right length differences using both ulnae. This approach assumes that ulnar length differences in a malunion population are similar to those in a healthy population. This study was conducted to analyze the difference in ulnar length in a distal radius malunion population and to assess the potential influence of age, sex, or malunion side on this difference. METHODS: We evaluated 65 adult patients with distal radius malunion using bilateral forearm CT scans. 3D models of both ulnae were constructed, and length differences were determined along a standardized length axis. The results were compared to two populations without a radius malunion. RESULTS: The average absolute ulnar length difference was 2.57 mm (SD 1.81), which was comparable to the two healthy populations. This difference was not significantly affected by age, sex, or malunion side. CONCLUSION: This study demonstrated that using the ulnar length difference to correct for radial length difference in the current 3D planning process, before using the contralateral radius as a template for a corrective osteotomy in patients with radius malunion, is safe.

Determining Sex from Thai Radius: Discriminant Function Analysis Including the Dry Bone Weight as an Effective Variant / Determinación del Sexo a Partir del Radio Tailandés: Análisis de Función Discriminante que Incluye el Peso del Hueso Seco como Variante Eficaz

SUMMARY: In forensic anthropology, the radius bone has been shown to determine the sex of human remains in a number of different populations. The dry mass and growth of long bones, including the radius, are associated with sex hormone levels; however, the use of bone weight to determine sex has not been sufficiently investigated. The aim of this study was to apply bone morphometric parameters, including maximum length of radius (MLR), circumference at the midshaft of radius (CMR), and weight of radius (WR), to 400 sample radii from a Northeastern Thai population. Univariate and multivariate discriminant functions of all parameters were systemically applied. Equations for calculating sex classification were also determined. Descriptive data analysis showed significant sexual dimorphism in all variables (p < 0.05). The canonical correlation was highest in CMR (0.772) and the ratio of weight to length (0.747). Multivariate discriminant function analysis showed that the measured indices of the right radius were slightly greater than those of the left radius. The parameters demonstrating the highest values of the standardized canonical discriminant function coefficients were CMR (Rt. = 0.496, Lt. 0.431) and WR (Rt. = 0.681, Lt. = 0.715). Moreover, the results of the multivariable (stepwise method) indicated that the best accuracy rates for using combinations of CMR and WR were 94 % (right side) and 92 % (left side). In conclusion, the weight of the radius (rather than the length) is an effective parameter in determining sex.

En antropología forense, se ha demostrado que el hueso radio determina el sexo de los restos humanos en varias poblaciones diferentes. La masa seca y el crecimiento de los huesos largos, incluido el radio, están asociados con los niveles de hormonas sexuales; sin embargo, el uso del peso de los huesos para determinar el sexo no se ha investigado suficientemente. El objetivo de este estudio fue aplicar parámetros morfométricos óseos, incluida la longitud máxima del radio (LMR), la circunferencia en la mitad del radio (CMR) y el peso del radio (PR), a 400 radios de muestra de una población del noreste de Tailandia. Se aplicaron sistémicamente funciones discriminantes univariadas y multivariadas de todos los parámetros. También se determinaron ecuaciones para calcular la clasificación por sexo. El análisis descriptivo de los datos mostró un dimorfismo sexual significativo en todas las variables (p < 0,05). La correlación canónica fue mayor en CMR (0,772) y la relación peso-longitud (0,747). El análisis de función discriminante multivariante mostró que los índices del radio derecho eran ligeramente mayores que los del radio izquierdo. Los parámetros que demostraron los valores más altos de los coeficientes de la función discriminante canónica estandarizada fueron CMR (Rt. = 0,496, Lt. 0,431) y PR (Rt. = 0,681, Lt. = 0,715). Además, los resultados del método multivariable (método paso a paso) indicaron que las mejores tasas de precisión al usar combinaciones de CMR y PR fueron del 94 % (lado derecho) y del 92 % (lado izquierdo). En conclusión, el peso del radio (más que la longitud) es un parámetro eficaz para determinar el sexo.

Radiographic evaluation of the forelimb bone development in maned wolves (Chrysocyon brachyurus).

This study aimed to assess the fusion of growth plates and the development of secondary ossification centres in the forelimb bones of maned wolves (Chrysocyon brachyurus), contrasting the findings with established data from domestic dogs. Three maned wolves, comprising one male and two females, initially aged between 3 and 4 months, were subjected to monthly radiographic evaluations until 10-11 months of age, followed by bimonthly assessments until 18-19 months of age, encompassing both forelimbs. The closure times of growth plates were observed as follows: supraglenoid tubercle (7-8 months), proximal humerus (17-19 months), distal humerus (8-9 months), medial epicondyle of the humerus (8-9 months), proximal ulna (9-10 months), proximal radius (13-15 months), distal ulna (13-15 months) and distal radius (17-19 months). Statistical analysis revealed significant differences in the areas of secondary ossification centres in the proximal epiphyses of the humerus and radius, respectively, observed from the initial evaluation at 8-9 months and 6-7 months. Conversely, the epiphyses of the supraglenoid tubercle, distal humerus, proximal ulna, distal ulna, medial epicondyle of the humerus and distal radius did not exhibit significant area differences between 3-4 months and 4-5 months, yet notable distinctions emerged at 5-6 months. In summary, while the radiographic appearance of epiphyseal growth plates and secondary ossification centres in maned wolves resembles that of domestic dogs, closure times vary. These findings contribute to understanding the dynamics of epiphyseal growth plates in this species.

Automatic identification of radius and ulna bone landmarks on 3D virtual models.

BACKGROUND: For bone morphology and biomechanics analysis, landmarks are essential to define position, orientation, and shape. These landmarks define bone and joint coordinate systems and are widely used in these research fields. Currently, no method is known for automatically identifying landmarks on virtual 3D bone models of the radius and ulna. This paper proposes a knowledge-based method for locating landmarks and calculating a coordinate system for the radius, ulna, and combined forearm bones, which is essential for measuring forearm function. This method does not rely on pre-labeled data. VALIDATION: The algorithm is validated by comparing the landmarks placed by the algorithm with the mean position of landmarks placed by a group of experts on cadaveric specimens regarding distance and orientation. RESULTS: The median Euclidean distance differences between all the automated and reference landmarks range from 0.4 to 1.8 millimeters. The median angular differences of the coordinate system of the radius and ulna range from -1.4 to 0.6 degrees. The forearm coordinate system's median errors range from -0.2 to 2.0 degrees. The median error in calculating the rotational position of the radius relative to the ulna is 1.8 degrees. CONCLUSION: The automatic method's applicability depends on the use context and desired accuracy. However, the current method is a validated first step in the automatic analysis of the three-dimensional forearm anatomy.

Automated Determination of Morphometric Parameters of the Human Radius Based on the Results of Its Computed Tomography.

A fundamentally new software method for automated measurement of morphometric parameters of computed tomographic image of the human radius has been designed. The parameters obtained by manual morphometry of computed tomograms using the RadiAnt DICOM Viewer software were compared with the results of the software product developed by us. The relative error in the measurement of morphometric parameters was about 10%. In the future, the presented software method of automated determination of morphometric parameters of the bone will enable modeling of individual prosthesis of the head of the radius based on the results of computed tomograms with consideration of the structural features of the human radius.

Anatomical features of the proximal end of the radius and its implications for implant design.

PURPOSE: The proximal radio-ulnar joint allows supination and pronation of the forearm and the humeroradial joint allows flexion and extension movements at the elbow joint. Although the proximal end of the radius is less common than other fractures, it is more common nowadays due to the prolongation of life expectancy, increased incidence of osteoporosis. There have been reports in the literature that success has not been achieved due to the lack of anatomical fit of the prosthesis. Knowledge of the morphometric features of the proximal end of the radius is important for the design of anatomically and biomechanically appropriate prostheses. METHODS: In this study, measurements of head and neck of radius, and radial tuberosity were measured in 80 dry radii. Parameters important for prosthesis design were analysed and their correlations examined. RESULTS: The shapes of radial head was found 36% oval and 64% circular. The mean heights of the radial head at anterior, posterior, medial, and lateral sides were 8.52 ± 1.32 mm, 9.02 ± 1.23 mm, 9.20 ± 1.59 mm, 8.05 ± 1.13 mm, respectively. The mean depth of articular facet were 1.85 ± 0.37 mm. It was determined that there was no high correlation between the parameters affecting the prosthesis design. CONCLUSIONS: Morphological and morphometric features of the proximal radius are important for prosthesis design and implantation. The ideal radial head prosthesis design is challenging due to numerous parameters, wide ranges and low correlation, although modular designs facilitate compatibility. The widespread use of 3D printing technologies is expected to reduce the potential complications associated with prosthesis applications.

Digital smart internal fixation surgery for coronal process basal fracture with normal joint spaces or radius-shortening: Occult factor of radius-ulna load sharing.

BACKGROUND: Reasonable postoperative humeroradial and humeroulnar joint spaces maybe an important indicator in biomechanical stability of smart internal fixation surgery for coronoid process basal fractures (CPBF). The aim of this study is to compare elbow articular stresses and elbow-forearm stability under smart internal fixations for the CPBF between normal elbow joint spaces and radius-shortening, and to determine the occult factor of radius-ulna load sharing. METHODS: CT images of 70 volunteers with intact elbow joints were retrospectively collected for accurate three-dimensional reconstruction to measure the longitudinal and transverse joint spaces. Two groups of ten finite element (FE) models were established prospectively between normal joint space and radius-shortening with 2.0 mm, including intact elbow joint and forearm, elbow-forearm with CPBF trauma, anterior or posterior double screws-cancellous bone fixation, mini-plate-cancellous bone fixation. Three sets of physiological loads (compression, valgus, varus) were used for FE intelligent calculation, FE model verification, and biomechanical and motion analysis. RESULTS: The stress distribution between coronoid process and radial head, compression displacements and valgus angles of elbow-forearm in the three smart fixation models of the normal joint spaces were close to those of corresponding intact elbow model, but were significantly different from those of preoperative CPBF models and fixed radius-shortening models. The maximum stresses of three smart fixation instrument models of normal joint spaces were significantly smaller than those of the corresponding fixed radius-shortening models. CONCLUSIONS: On the basis of the existing trauma of the elbow-forearm system in clinical practice, which is a dominant factor affecting radius-ulna load sharing, the elbow joint longitudinal space has been found to be the occult factor affecting radius-ulna load sharing. The stability and load sharing of radius and ulna after three kinds of smart fixations of the CPBF is not only related to the anatomical and biomechanical stability principles of smart internal fixations, but also closely related to postoperative elbow joint longitudinal space.

Developmental Anatomy of the Radial Bow in Pediatric Patients Using 3D Imaging.

BACKGROUND: While radial bow shape is well characterized in adults, its development in children is not well understood. Previous studies on the radial bow use radiographs, thus, rotational positioning of the forearm could alter bowing measurements. This study used 3D imaging to better assess the pediatric radial bow. METHODS: Computed tomography scans from the New Mexico Decedent Image Database were obtained for ages 2 to 16 (females) and 18 (males) (n=152). 3D models were generated using Slicer and Rhino software. Length of the entire radial bow (bicipital tuberosity to sigmoid notch), maximum radial bow, location of the maximum radial bow (bicipital tuberosity to the point of maximum bowing), and distal, middle, and proximal third radial bows were measured. RESULTS: The length of the entire bow increased with age, with a strong correlation with age ( r =0.90, P <0.01). The maximum bow increased with age, with a strong correlation with age ( r =0.78, P <0.01). The maximum bow normalized to the length of the entire bow increased mildly with age, mean 0.059 ± 0.012 ( r =0.24, P =0.0024), but seems to plateau around age 8. The location of the maximum bow increased with age ( r =0.85, P <0.01). The normalized location of the maximum bow remained constant between ages, with a mean of 0.41 ± 0.10 ( r =0.12, P =0.14). The normalized distal third bow mildly increased with age ( r =0.34, P <0.01), the normalized middle third bow mildly increased with age ( r =0.25, P <0.01), and the normalized proximal third bow remained constant between ages ( r =0.096, P =0.24). CONCLUSIONS: Normalized values for maximum, distal third, and middle third radial bow increase with age, while normalized values for location and proximal third radial bow remain relatively constant, suggesting the proportional shape of the radius changes during development, although qualitatively plateaus after age 8. LEVEL OF EVIDENCE: Retrospective comparative study, Level-III.

Development of a simplified new method of bone age estimation using three bones of the hand and wrist.

Though the Greulich and Pyle (GP) method is easy, inter-observer variability, differential maturation of hand bones influences ratings. The Tanner-Whitehouse (TW) method is more accurate, but cumbersome. A simpler method combining the above, such that it utilizes fewer bones without affecting accuracy, would be widely used and more applicable in clinical practice. OBJECTIVES: 1. Devising a simplified method utilizing three bones of the hand and wrist for bone age (BA) assessment. 2. Testing whether the 3 bone method gives comparable results to standard methods (GP,TW2,TW3) in Indian children. METHODS: Developmental stages and corresponding BA for radius, hamate, terminal phalanx (left middle finger) epiphyses combining stages from GP,TW3 atlases were described; BA were rated by two blinded observers. 3 bone method ratings were compared with the same dataset analyzed earlier using GP,TW2,TW3 (4 raters). RESULTS: Radiographs analysed:493 (Girls=226). Mean chronological age:9.4 ± 4.6 yrs, mean BA 3 bone:9.8 ± 4.8 yrs, GP:9.6 ± 4.8 yrs, TW3:9.3 ± 4.5 yrs, TW2:9.9 ± 5.0 yrs. The 3 bone method demonstrated no significant inter-observer variability (p = 0.3, mean difference = 0.02 ± 0.6 yrs); a strong positive correlation (p < 0.0001) with GP (r = 0.985), TW3 (r = 0.983) and TW2 (r = 0.982) was noted. Bland-Altman plots demonstrated good agreement; the root mean square errors between 3 bone and GP,TW3,TW2 ratings were 0.6,0.7,0.6 years; mean differences were 0.19,0.49,-0.14 years respectively. Greatest proportion of outliers (beyond ±1.96 SD of mean difference) was between 6 and 8 years age for difference in 3 bone and GP, and between 4-6 years for difference in 3 bone and TW3,TW2. CONCLUSION: The 3 bone method has multiple advantages; it is easier, tackles differential maturation of wrist and hand bones, has good reproducibility, without compromising on accuracy rendering it suitable for office practice.

[Support algorithm for lateral elbow pain syndrome in adults]. / Douleurs latérales du coude chez l'adulte : algorithme de prise en charge.

Lateral elbow pain syndrome in adults is a frequent complaint leading to consultation in primary care medicine. The lateral side of the elbow joint represents a complex anatomy with close proximity of bony structures (humerus, radius, and ulna), ligaments (lateral ligament complex), tendons (origin of the extensors of the wrist and fingers), and nerves (branches of the radial nerve) making diagnostic and therapeutic management demanding. This article aims to provide a basis for reflection to better define treatment options for pathologies frequently encountered in clinical practice.

Les douleurs de la face latérale du coude chez l'adulte sont un motif fréquent de consultation en médecine de premier recours. La face latérale de cette articulation représente une anatomie complexe avec une proximité des structures osseuses (humérus, radius et ulna), ligamentaires (complexe ligamentaire latéral), tendineuses (origine des extenseurs du poignet et des doigts) et nerveuses (branches du nerf radial) rendant l'orientation diagnostique et la prise en charge thérapeutique exigeantes. Cet article propose une base de réflexion pour mieux définir les options de prises en charge des pathologies fréquemment retrouvées en pratique clinique.

Radiological Evaluation of Volar Cortical Angle in the Anatolian Population / Evaluación Radiológica del Ángulo Cortical Volar en la Población Anatoliana

SUMMARY: Distal radius fractures are the most common fractures of the upper limb. The most commonly used method in the repair of these fractures is volar locking plates. Recently, the frequency of removal of volar locking plates after surgery has increased. There are many factors in its reduction. Anatomically, incompatibility of the distal end of the radius with volar locking plates is one of them. In previous studies, different volar cortical angle (VCA) values were found in other races. For this reason, this study aimed to determine the mean values by making VCA measurements of the Anatolian population. The study was designed retrospectively. In the study, measurements were made on computed tomography (CT) images of the distal end of the radius of 53 men and 28 women. Radial width, intermediate volar angle, and radial volar angle were measured in the images. On average, the radius width was 23.35±1.96 mm, and the intermediate volar angle was 26.02±.3.83°, radial volar angle was 24±3.07°. Radial width, intermediate volar angle, and radial volar angle differed significantly by gender (p<0.001). A significant correlation was found between radius width, intermediate volar angle, and radial volar angle values (p<0.001). It has been determined that the Anatolian population has a different VCA value than the European, Asian, and other populations. When using volar locking plates in distal radius fracture surgery, volar locking plates should be selected by considering the average values of the races.

Las fracturas del radio distal son las fracturas más comunes del miembro superior. El método más utilizado en la reparación de estas fracturas son las placas de bloqueo volar. Recientemente, ha aumentado la frecuencia de extracción de placas de bloqueo volar después de la cirugía. Existen muchos factores en su reducción y anatómicamente, la incompatibilidad de la extremidad distal del radio con las placas de bloqueo volar es una de ellas. En estudios anteriores, se encontraron diferentes valores del ángulo cortical volar (VCA) en otras grupos. Por esta razón, este estudio tuvo como objetivo determinar los valores medios, realizando mediciones de VCA de la población de Anatolia. El estudio fue diseñado de manera retrospectiva. En el estudio, se realizaron mediciones en imágenes de tomografía computarizada (TC) de la extremidad distal del radio de 53 hombres y 28 mujeres. En las imágenes se midieron el ancho radial, el ángulo volar intermedio y el ángulo volar radial. En promedio, el ancho del radio fue de 23,35 ± 1,96 mm, el ángulo volar intermedio fue de 26,02 ± 3,83° y el ángulo volar radial fue de 24 ± 3,07°. El ancho radial, el ángulo volar intermedio y el ángulo volar radial difirieron significativamente según el sexo (p<0,001). Se encontró una correlación significativa entre los valores del ancho del radio, el ángulo volar intermedio y el ángulo volar radial (p<0,001). Se ha determinado que la población de Anatolia tiene un valor de VCA diferente al de las poblaciones europeas, asiáticas y otras. Cuando se utilizan placas de bloqueo volar en cirugía de fractura de la extremidad distal del radio, las placas deben seleccionarse considerando los valores promedio de los individuos de diferentes grupos.

The accuracy of Cameriere methods in Turkish children: chronological age estimation using developing teeth and carpals and epiphyses of the ulna and radius.

The aim of the present study was to develop a specific formula by measuring the developing teeth, carpal bones, and epiphyses of the ulna and radius to determine the chronological age in Turkish children. The left developing permanent mandibular teeth were evaluated, and the number of teeth with closed apex was recorded. The distance between the inner sides of open apex/apices was measured by using the ImageJ program and divided by the tooth length. The sum of the normalized open apices was also calculated. The carpal area (Ca), covering the epiphyses of ulna and radius and the carpal bones, was measured on the X-rays of left hand. The areas of each carpal bone and epiphyses of the ulna and radius were measured, and these measurements were added together to obtain the bone area (Bo). The Bo/Ca ratio between the total area of carpal bones and the carpal area was calculated to normalize the measurements. The accuracy of the equations formulated by Cameriere was evaluated, and a new regression equation was developed accordingly. The new formula showed no statistically significant difference between the chronological and the estimated age for females, males, and total sample. The new formula, which hit the age with 72.80% accuracy, was more successful in predicting chronological age than other adjusted regression equations. The new regression model, created for the Turkish children by using both developing teeth and hand-wrist bones, was considerably successful in estimating the chronological age.

Sex assessment using the radius bone in a French sample when applying various statistical models.

Sex estimation of skeletal remains is one of the most important tasks in forensic anthropology. The radius bone is useful to develop standard guidelines for sex estimation across various populations and is an alternative when coxal or femoral bones are not available.The aim of the present study was to assess the sexual dimorphism from radius measurements in a French sample and compare the predictive accuracy of several modelling techniques, using both classical statistical methods and machine learning algorithms.A total of 78 left radii (36 males and 42 females) were used in this study. Sixteen measurements were made. The modelling techniques included a linear discriminant analysis (LDA), flexible discriminant analysis (FDA), regularised discriminant analysis (RDA), penalised logistic regression (PLR), random forests (RF) and support vector machines (SVM).The different statistical models showed an accuracy of classification that is greater than 94%. After selection of variables, the accuracies increased to 97%. The measurements made at the proximal part of the radius (sagittal and transversal diameters of the head, and sagittal diameter of the neck), at distal part (maximum width of the distal epiphysis) and of the entire bone (maximum length) stand out among the various models.The present study suggests that the radius bone constitutes a valid alternative for sex estimation of skeletal remains with comparable classification accuracies to the pelvis or femur and that the non-classical statistical models may provide a novel approach to sex estimation from the radius bone. However, the extrapolation of the current results cannot be made without caution because our sample was composed of very aged individuals.

Anatomy of the distal radioulnar ligament in cats.

OBJECTIVES: The aim of this study was to describe the anatomy of the distal radioulnar ligament in the cat, using gross and histological sections from cadaveric feline carpi. METHODS: Eight feline cadaveric distal radioulnar joints were included in the study, including six that were paraffin- and two that were polymethyl methacrylate-embedded. Each of the sections of the distal radioulnar joint and ligament were viewed macroscopically and microscopically using a dissection microscope and a standard light microscope with polarising capacity. RESULTS: On gross examination, the distal radioulnar ligament could be seen as a triangular-shaped structure extending between the dorsal surface of the distal radius and ulna. The centre of the ligament had a greater density of tightly packed collagen fibres, while fibrocartilage was identified at the site of both the radial and ulnar entheses. Articular cartilage was noted to extend to the most proximal part of the bulbous portion of the distal ulna and corresponding axial aspect of the distal radius. CONCLUSIONS AND RELEVANCE: In the cat, there appears to be a less extensive interosseous component of the distal radioulnar ligament compared with the dog and cheetah. Instead, the ligament follows the articular surfaces of the distal radius and ulna. These anatomical differences may account for increased rotation of the feline antebrachium and have clinical implications, particularly with regard to the management of antebrachiocarpal joint injuries.

Radiographic morphometry of the distal end radius in Anatolian population / Morfometría radiográfica del extremo distal del radio en la población de Anatolia

SUMMARY: Distal radius fractures are one of the most common orthopedic injuries encountered by orthopedic surgeons. Correction of dorsal tilt and radial height is essential to restore normal biomechanics of the wrist joint. Comprehensive knowledge of the morphometry of the distal radius of the local population becomes critical for the treating surgeon. This study aims to report the morphometry of the distal radius in the Anatolian population and compare it with similar studies in other races and humans. Radiographs of one hundred and twenty-four people were included in the study. Four radiological parameters were examined on all radiographs: radial height, radial tilt, ulnar variance, and palmar tilt. Radial tilt was 23.35°±1.96; palmar tilt was 15.7°±2,87 radial height (mm) was 10.55±4.34, ulnar variance (mm) was 0.32±1.79. The highest rate of negative ulnar variance was found. According to the study's results, reference data varying by race for anatomical fit should be considered in treating DER injuries.

Las fracturas de la parte distal del radio son probablemente las lesiones ortopédicas más comunes que encuentran los cirujanos ortopédicos. La corrección de la inclinación dorsal y la altura radial es esencial para restaurar la biomecánica normal de la articulación de la muñeca. El conocimiento integral de la morfometría del radio distal de la población local es importante para el cirujano tratante. Este estudio tuvo como objetivo reportar la morfometría de la parte rdistal del radio en la población de Anatolia y compararla con estudios similares en otras razas y humanos. Se incluyeron ciento veinticuatro radiografías simples consecutivas de la articulación de la muñeca. Se examinaron cuatro parámetros radiológicos: altura radial, inclinación radial, variación ulnar e inclinación palmar. El ángulo de inclinación radial fue de 23,35±1,96; el ángulo de inclinación palmar fue de 15,7±, la altura radial (mm) fue de 10,55±4,34, la varianza ulnar (mm) fue de 0,32±1,79. Se encontró la tasa más alta de varianza ulnar negativa (43,5%). Los resultados de este estudio deben tenerse en consideración al tratar fracturas de la parte distal del radio, con datos de referencia que varían según la raza para el ajuste anatómico.

Three-dimensional imaging of the distal radius with reference to volar locking plate surgery.

BACKGROUND: The watershed line is widely accepted as the distal limit of the volar locking plate (VLP); however, the VLP placement could vary depending on the plate contour and morphology of the distal radius. The aim of this study was to investigate the morphology of the distal radius and VLP fitting using 3D images. HYPOTHESIS: We hypothesized that attachment of the VLP would affect the contour of the volar prominence of the distal radius. PATIENTS AND METHODS: Variable-angle LCP two-column volar distal radius Plate 2.4 and 16 formalin-fixed cadavers were studied. The plate and forearm were scanned using a computed tomography scanner. The plate was fixed to the radial shaft in the most distal position without flexor pollicis longus tendon contact. Postero-antero and lateral radiographs were obtained using fluoroscopy. Postero-antero radiographs were superimposed on a 3D image of the distal radius. The virtual plate was attached to the distal radius in the computer simulations and the plate was adjusted in the sagittal plane. In the postero-antero radiographs, the distance between the plate and distal end of the radius (DPR) was measured. In the sagittal plane, the height of the volar lunate facet (VLF) and the plate-to-bone distance of each locking screw hole was measured. The volar cortical angle (VCA) was measured as the angle formed by a line drawn along the volar surface and a line drawn on the radial shaft on the sagittal plane at each locking screw plane. RESULTS: A significant correlation was observed between the height of the VLF and the DPR and between the height of the VLF and the VCA. The plate-to-bone distance at the ulnar screw hole was significantly smaller than that of the other screw holes. DISCUSSION: Our study revealed that the higher the VLF, the more proximal is the VLP. The plate fits on the bone surface at the ulnar side, whereas the radial side has more space between the plate and bone. LEVEL OF EVIDENCE: III, diagnostic Level.

Anatomic factors associated with partial distal biceps tendon tears: a comparative control study.

BACKGROUND: There is minimal literature on the anatomic factors associated with partial distal biceps tendon (DBT) tears. It has been proposed that a larger radial tuberosity size-and, therefore, a smaller radioulnar space during pronation-may cause mechanical impingement of the DBT predisposing to tears. We sought to investigate the anatomic factors that may be associated with partial DBT tears by retrospectively reviewing the DBT anatomy using 3-T magnetic resonance imaging (MRI) scans of elbows with partial DBT tears and a comparison group of normal elbows. METHODS: Two independent observers retrospectively reviewed 3-T MRI scans of elbows with partial DBT tears and elbows without visible pathology. Basic demographic data were collected, and measurements of radial tuberosity length, radial tuberosity thickness, radioulnar space, and radial tuberosity-ulnar space were made using simultaneous tracker lines and a standardized technique. The ratio of radial tuberosity thickness to radial diameter and the ratio of radioulnar space to radial tuberosity-ulnar space were calculated. The presence or absence of enthesophytes and the presence of a single DBT vs. double DBTs were noted. RESULTS: This study included twenty-six 3-T MRI scans of 26 elbows with partial DBT tears and thirty 3-T MRI scans of 30 elbows without pathology. Basic demographic data were comparable between the 2 groups. The tear group showed statistically significantly larger mean measurements for radial tuberosity length (24.3 mm vs. 21.3 mm, P = .002) and radial tuberosity thickness (5.5 mm vs. 3.7 mm, P < .0001). The tear group also showed statistically significantly smaller measurements for radioulnar space (8.2 mm vs. 10.0 mm, P = .010) and radial tuberosity-ulnar space (7.2 mm vs. 9.1 mm, P = .013). The ratio of radial tuberosity thickness to radial diameter was statistically significantly larger in the tear group (0.389 vs. 0.267, P < .0001). There was a statistically significant positive correlation between partial DBT tears and the presence of enthesophytes (P = .007), as well as between partial DBT tears and the presence of 2 discrete DBTs rather than a single tendon or 2 DBTs that interdigitated prior to insertion (P < .0001). CONCLUSION: Larger radial tuberosities and smaller radioulnar and radial tuberosity-ulnar spaces are associated with partial DBT tears. Larger tuberosities and a smaller functional space for the DBT may lead to chronic impingement, tendon delamination, and consequent weakness, which ultimately lead to tears. Enthesophytes may be associated with tears for the same reason. The presence of 2 discrete DBTs that do not interdigitate prior to insertion is also associated with partial tears. This study will help clinicians understand the pathogenesis of partial DBT tears.

Bone Microarchitecture in Transgender Adults: A Cross-Sectional Study.

Gender-affirming hormone therapy aligns physical characteristics with an individual's gender identity, but sex hormones regulate bone remodeling and influence bone morphology. We hypothesized that trans men receiving testosterone have compromised bone morphology because of suppression of ovarian estradiol production, whereas trans women receiving estradiol, with or without anti-androgen therapy, have preserved bone microarchitecture. We compared distal radial and tibial microarchitecture using high-resolution peripheral quantitative computed tomography images in a cross-sectional study of 41 trans men with 71 cis female controls, and 40 trans women with 51 cis male controls. Between-group differences were expressed as standardized deviations (SD) from the mean in age-matched cisgender controls with 98% confidence intervals adjusted for cross-sectional area (CSA) and multiple comparisons. Relative to cis women, trans men had 0.63 SD higher total volumetric bone mineral density (vBMD; both p = 0.01). Cortical vBMD and cortical porosity did not differ, but cortices were 1.11 SD thicker (p < 0.01). Trabeculae were 0.38 SD thicker (p = 0.05) but otherwise no different. Compared with cis men, trans women had 0.68 SD lower total vBMD (p = 0.01). Cortical vBMD was 0.70 SD lower (p < 0.01), cortical thickness was 0.51 SD lower (p = 0.04), and cortical porosity was 0.70 SD higher (p < 0.01). Trabecular bone volume (BV/TV) was 0.77 SD lower (p < 0.01), with 0.57 SD fewer (p < 0.01) and 0.30 SD thicker trabeculae (p = 0.02). There was 0.56 SD greater trabecular separation (p = 0.01). Findings at the distal radius were similar. Contrary to each hypothesis, bone microarchitecture was not compromised in trans men, perhaps because aromatization of administered testosterone prevented bone loss. Trans women had deteriorated bone microarchitecture either because of deficits in microstructure before treatment or because the estradiol dosage was insufficient to offset reduced aromatizable testosterone. Prospective studies are needed to confirm these findings. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Madelung Deformity - Esthetic and Functional Outcomes from the Surgical Treatment with Distal Radial Dome Osteotomy and Vickers Ligament Section / Deformidade de Madelung - Resultado estético e funcional do tratamento cirúrgico com osteotomia em cúpula do rádio distal e secção do ligamento de Vickers

Abstract Objective The present study aimed to evaluate esthetic and functional outcomes from the surgical treatment of Madelung deformity in children. MethodThis is a retrospective study of pediatric patients with Madelung deformity who were surgically treated with dome osteotomy of the distal radius and Vickers ligament section from 2015 to 2018. Patients with a minimum postoperative follow-up period of 12 months were included. Demographic data, surgical technique, clinical and radiographic outcomes were analyzed. Pre and postoperative radiographic evaluation consisted of ulnar tilt, lunate subsidence lunate fossa angle, and palmar carpal displacement measurements. The postoperative clinical evaluation consisted of ranges of motion of the wrist, visual analog scale (VAS) and Disabilities of the Arm, Shoulder and Hand (DASH) score. Results Four patients were included, two with idiopathic Madelung deformity and two with bone dysplasia. All patients were females and presented bilateral disease. Six wrists were operated on. The median age at surgery was 15.5 years old, and the median postoperative follow-up time was of 37.5 months. The postoperative radiographic analysis revealed an average correction of 8.8 ± 7.5° for ulnar tilt, 3.0 ± 3.9 mm for lunate subsidence 8.2 ± 6.6° for lunate fossa angle, and 4.7 ± 2.6 mm for palmar carpal displacement. Average postoperative ranges of motion of the wrist joint were 75.8 ± 3.4° for flexion, 62.5 ± 14.1° for extension, 25.7 ± 2.9° for radial deviation, 40.0 ± 2.9° for ulnar deviation, 88.3 ± 2.4° for pronation, and 82.5 ± 2.5° for supination. The median VAS was 1 for residual pain, 0 for functional deficit, 0 for esthetic impairment, and 10 for recommending the surgical procedure. The median DASH score was 0. Conclusion Madelung deformity treatment using dome osteotomy of the distal radius and Vickers ligament section results in excellent esthetic and functional outcomes.

Resumo Objetivo Avaliar o resultado estético e funcional do tratamento cirúrgico da deformidade de Madelung em idade pediátrica. MétodoEstudo retrospectivo dos pacientes com deformidade de Madelung em idade pediátrica tratados cirurgicamente através de osteotomia em cúpula do rádio distal e secção do ligamento de Vickers entre 2015 e 2018. Foram incluídos doentes com tempo de seguimento pós-operatório mínimo de 12 meses. Foram analisados dados demográficos, técnica cirúrgica, resultados clínicos e radiográficos. A avaliação radiográfica pré e pós-operatória consistiu na medição da inclinação ulnar, do afundamento semilunar, do ângulo da fossa semilunar e do desvio palmar do carpo. A avaliação clínica pós-operatória consistiu na medição das amplitudes articulares do punho, escala visual analógica (EVA) e score Disabilities of the Arm, Shoulder and Hand (DASH). Resultados Foram incluídos quatro pacientes, dois com Madelung idiopática e dois com displasia óssea, todos do sexo feminino e com doença bilateral. Foram operados 6 punhos, a idade mediana à data de cirurgia foi 15,5 anos, e o tempo mediano de seguimento pós-operatório foi de 37,5 meses. Na análise radiográfica pós-operatória, verificou-se uma correção média de 8,8 ± 7,5° da inclinação ulnar, de 3 ± 3,9 mm do afundamento semilunar, de 8,2 ± 6,6° do ângulo da fossa semilunar e de 4,7 ± 2,6 mm do desvio palmar do carpo. Na avaliação da amplitude articular média pós-operatória, registrou-se uma flexão de 75,8 ± 3,4°; extensão de 62,5 ± 14,1°; desvio radial de 25,7 ± 2,9°; desvio cubital de 40,0 ± 2,9; pronação de 88,3 ± 2,4°; supinação de 82,5 ± 2,5°. Registou-se EVA mediana para dor residual = 1, défice funcional = 0, prejuízo estético = 0, e recomendação de procedimento cirúrgico = 10. A mediana do score DASH foi 0. Conclusão O tratamento da deformidade de Madelung através da osteotomia em cúpula do rádio distal e secção do ligamento de Vickers permite obter um excelente resultado estético e funcional.