[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.

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.

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.

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.

Age-Related Changes in Bone Density, Microarchitecture, and Strength in Postmenopausal Black and White Women: The SWAN Longitudinal HR-pQCT Study.

Higher fracture risk in White versus Black women is partly explained by lower BMD and worse bone microarchitecture in White women. However, whether rates of decline in bone density, microarchitecture and strength differ between postmenopausal Black and White women is unknown. Further, factors that influence rates of age-related bone microarchitecture deterioration remain ill-defined. Thus, over 6.7 years, longitudinal changes were measured in peripheral volumetric bone mineral density (vBMD), microarchitecture, and strength at the distal radius and tibia using HR-pQCT in postmenopausal Black (n = 80) and White (n = 137) women participating in the Study of Women's Health Across the Nation. It was assessed whether age-related changes in vBMD and microarchitecture were influenced by body weight, body composition, and/or weight change. It was found that at the radius, where White women appeared to have slightly greater rates of loss in total vBMD, cortical bone volume, and porosity than Black women, those differences were attenuated after adjusting for clinical covariates. At the tibia, Black and White women had similar rates of bone loss. Independent of race and other clinical covariates, women with the lowest baseline body weight experienced the greatest decline in total and trabecular vBMD at the radius. Furthermore, women who lost weight over the follow-up period had higher rates of bone loss, particularly at the tibia, compared with those who maintained or gained weight. Higher baseline total body fat mass was also protective of bone loss at both the radius and tibia. In conclusion, these findings indicate that lower fracture risk among postmenopausal Black women is not caused by slower rates of bone deterioration, and highlight the importance for postmenopausal women to avoid lower body weight and excessive weight loss to avert rapid bone loss and subsequent fractures. © 2021 American Society for Bone and Mineral Research (ASBMR).

Morphological symmetry of the radius and ulna-Can contralateral forearm bones utilize as a reliable template for the opposite side?

The most important precondition for correction of the affected forearm using data from the contralateral side is that the left and right bone features must be similar, in order to develop patient-specific instruments (PSIs) and/or utilize computer-assisted orthopedic surgery (CAOS). The forearm has complex anatomical structure, and most people use their dominant hand more than their less dominant hand, sometimes resulting in asymmetry of the upper limbs. The aim of this study is to investigate differences of the bilateral forearm bones through a quantitative comparison of whole bone parameters including length, volume, bowing, and twisting parameters, and regional shape differences of the forearm bones. In total, 132 bilateral 3D radii and ulnae 3D models were obtained from CT images, whole bone parameters and regional shape were analyzed. Statistically significant differences in whole bone parameters were not shown. Regionally, the radius shows asymmetry in the upper section of the central part to the upper section of the distal part. The ulna shows asymmetry in the lower section of the proximal part to the lower section of the central part. Utilizing contralateral side forearm bones to correct the affected side may be feasible despite regional differences in the forearm bones of around 0.5 mm.

Relationship between the Branching Patterns of the Radial Nerve and Supinator Muscle.

The posterior interosseous nerve (PIN) innervates the posterior compartment muscle of the forearm and is a continuation of the deep branch of the radial nerve. The anatomic descriptions of PIN vary among different authors. This study investigated the distribution patterns of PIN and its relationships to the supinator muscle. This study investigated which nerves innervate the posterior compartment muscles of the forearm, the radial nerve, and the PIN, using 28 nonembalmed limbs. Also, the points where the muscle attaches to the bone were investigated. The measured variables in this study were measured from the most prominent point of the lateral epicondyle of the humerus (LEH) to the most distal point of the radius styloid process. For each specimen, the distance between the above two points was assumed to be 100%. The measurement variables were the attachment area of the supinator and branching points from the radial nerve. The attachment points of the supinator to the radius and ulna were 47.9% ± 3.6% and 31.5% ± 5.2%, respectively, from the LEH. In 67.9% of the specimens, the brachioradialis and extensor carpi radialis longus (ECRL) were innervated by the radial nerve before superficial nerve branching, and the extensor carpi radialis brevis (ECRB) innervated the deep branch of the radial nerve. In 21.4% of the limbs, the nerve innervating the ECRB branched at the same point as the superficial branch of the radial nerve, whereas it branched from the radial nerve in 7.1% of the limbs. In 3.6% of the limbs, the deep branch of the radial nerve branched to innervate the ECRL. PIN was identified as a large branch without divisions in 10.7% and as a deep branch innervating the extensor digitorum in 14.3% of the limbs. The anatomic findings of this study would aid in the diagnosis of PIN syndromes.

A proximal radius of Barberapithecus huerzeleri from Castell de Barberà: Implications for locomotor diversity among pliopithecoids.

Pliopithecoids are a diverse group of Miocene catarrhine primates from Eurasia. Their positional behavior is still unknown, and many species are known exclusively from dentognathic remains. Here, we describe a proximal radius (IPS66267) from the late Miocene of Castell de Barberà (Vallès-Penedès Basin, NE Iberian Peninsula) that represents the first postcranial specimen of the pliopithecoid Barberapithecus huerzeleri. A body mass estimate based on the radius is compared with dental estimates, and its morphology is compared with that of extant and fossil anthropoids by qualitative means as well as by landmark-based three-dimensional geometric morphometrics. The estimated body mass of ∼5 kg for IPS66267 closely matches the dental estimates for the (female) holotype, thereby discounting an alternative attribution to the large-bodied hominoid recorded at Castell de Barberà. In multiple features (oval and moderately tilted head with a pronounced lateral lip and a restricted articular area for the capitulum; proximodistally expanded proximal radioulnar joint; and short, robust, and anteroposteriorly compressed neck), the specimen differs from hominoids and resembles instead extant nonateline monkeys and stem catarrhines. The results of the morphometric analysis further indicate that the Barberapithecus proximal radius shows closer similarities with nonsuspensory arboreal cercopithecoids and the dendropithecid Simiolus. From a locomotor viewpoint, the radius of Barberapithecus lacks most of the features functionally related to climbing and/or suspensory behaviors and displays instead a proximal radioulnar joint that would have been particularly stable under pronation. On the other hand, the Barberapithecus radius differs from other stem catarrhines in the less anteroposteriorly compressed and less tilted radial head with a deeper capitular fovea, suggesting a somewhat enhanced mobility at the elbow joint. We conclude that pronograde arboreal quadrupedalism was the main component of the locomotor repertoire of Barberapithecus but that, similar to other crouzeliids, it might have displayed better climbing abilities than pliopithecids.

Anatomical features of some bones of the forelimbs of lions (Panthera leo) / Características anatómicas de algunos huesos de los miembros torácicos de leones (Panthera leo)

SUMMARY: We studied the bones of forelimb of four adult lions (Panthera leo) of both sexes to record the gross anatomical and morphometrical features of the scapula, humerus, radius and ulna. We observed some unique anatomical features that will be helpful for radiographic interpretation and forensic investigations. The lateral surface of scapula was unequally divided into supraspinous (fossa supraspinata) and infraspinous fossa (fossa infraspinata) by a well developed spine (spina scapulae). The acromion process was subdivided into suprahamate process (processus suprahamatus)and hamate process (processus hamatus); the later one was over hanged the glenoid cavity (cavitas glenoidalis), but the supraglenoid tubercle (tuberculum supraglenoidalis) was absent. The shaft (diaphysis) of humerus was compressed craniocaudally in proximal part, rounded to oval in middle part and compressed mediolaterally in distal part. A long, narrow supracondyloid foramen was found at distal limb just above the medial epicondyle (epicondylus medialis) which didn't connect the radial fossa (fossa radialis) with the olecranon fossa (fossa olecrani). The radius and ulna were twin bones where radius was articulated craniolateral to the ulna proximally and craniomedial to the ulna distally. However, the ulna was the longest bone in the forelimb of lion. The olecranon tuberosity of this bone had three prominences - two were cranially, whereas the caudal one was the largest and rounded. Distally projected styloid processes (processus styloideus) were found in the distal limb of both radius and ulna.

RESUMEN: Estudiamos los huesos de las miembros torácicos de cuatro leones adultos (Panthera leo) de ambos sexos para registrar las características anatómicas y morfométricas macroscópicas de la escápula, el húmero, el radio y la ulna. Se observaron algunas características anatómicas únicas que serán útiles para la interpretación radiográfica y las investigaciones forenses. La superficie lateral de la escápula se dividió de manera desigual en fosa supraespinosa y fosa infraspinosa por una columna bien desarrollada (espina de la escápula). El proceso del acromion se subdividió en proceso suprahamato (processus suprahamatus) y proceso hamato (processus hamatus); el tubérculo supraglenoideo (tuberculum supraglenoidalis) estaba ausente. La diáfisis (diafisis) del húmero estaba comprimida craneocaudalmente en la parte proximal, redondeada a ovalada en la parte media y comprimida mediolateralmente en la parte distal. Se encontró un foramen supracondileo largo y estrecho en la extremidad distal, por encima del epicóndilo medial (epicondylus medilaris) que no conectaba la fosa radial (fosa radial) con la fosa olecraneana (fossa olecrani). El radio y la ulna eran huesos idénticos en los que el radio se articulaba craneolateral a la ulna proximalmente, y craneomedial a la ulna distalmente. Sin embargo, la ulna era el hueso más largo del miembro torácico del león. La tuberosidad del olécranon de este hueso tenía tres prominencias: dos eran craneales, mientras que la caudal era la más grande y redondeada. Se encontraron procesos estiloides proyectados distalmente (processus styloideus) en la extremidades distales del radio y la ulna.

Estudio morfométrico del radio proximal en una población chilena / Morphometric study of the proximal radius in a Chilean population

RESUMEN: El objetivo de esta investigación fue determinar la morfometría del extremo proximal del radio, mediante mediciones efectuadas en la cabeza, cuello y tuberosidad del radio, en una población chilena y compararlas según sexo. Se efectuó un estudio transversal analizando exámenes de Tomografía Computarizada (TC) de codo, realizados entre enero de 2014 y diciembre de 2018. Se incluyó 32 TC, correspondientes a 16 hombres y 16 mujeres. Se transfirió las imágenes formateadas al software RadiAnt, para efectuar las mediciones en el radio proximal. El análisis estadístico de los resultados se realizó mediante el software SPSS 22. El diámetro de la cabeza del radio en hombres osciló entre 22,8±1,3 y 25,0±1,7 mm; en mujeres osciló entre 19,4±1,4 y 20,7±1,4 mm. El diámetro del cuello del radio proximal en hombres osciló entre 14,0±0,8 y 15,6±0,7 mm; en mujeres osciló entre 11,7±0,8 y 13,3±1,3 mm. El diámetro del cuello del radio distal en hombres osciló entre 14,4±1,0 y 16,0±1,2 mm; en mujeres osciló entre 12,5±1,0 y 13,8±1,5 mm. El diámetro de la tuberosidad radial en hombres osciló entre 15,1±1,5 y 17,7±1,8 mm; en mujeres osciló entre 13,2±1,1 y 15,5±1,8 mm. El promedio de altura de la cabeza del radio fue de 11,2±1,2 mm en hombres y de 9,5+0,8 mm en mujeres. El análisis comparativo entre sexos mostró diferencias estadísticamente significativas en todas las mediciones precedentes. El promedio de altura del cuello del radio fue de 11,2±1,2 mm en hombres y 10,1±1,6 mm en mujeres, sin diferencia significativa (p= 0,15). Los valores promedios de la morfometría del radio proximal de la población chilena difieren de los descritos para la población europea y presentan algunas similitudes con la población china. Nuestros resultados pueden ser de utilidad para el diseño de implantes y prótesis para el extremo proximal del radio y para una correcta planificación quirúrgica en ortopedia y traumatología.

SUMMARY: The aim of this research was to determine the morphometry of the proximal radius in a Chilean population, by means of measurements made in head of radius, neck of radius and radial tuberosity, and to compare them according to sex. A cross-sectional study was conducted analyzing Computed Tomography scans (CT) of elbows, performed between January 2014 and December 2018. Thirty-two CT corresponding to 16 men and 16 women were included. The formatted images were transferred to the RadiAnt software in order to perform measurements in the proximal radius. The statistical analysis of the results was performed using the SPSS 22 software. The diameter of the head of radius in men ranged between 22.8±1.3 and 25.0±1.7 mm; in women it ranged between 19.4±1.4 and 20.7±1.4 mm. The diameter of the proximal neck of radius in men ranged between 14.0±0.8 and 15.6±0.7 mm; in women, it ranged between 11.7±0.8 and 13.3±1.3 mm. The diameter of the distal neck of radius in men ranged between 14.4±1.0 and 16.0±1.2 mm; in women, it ranged between 12.5±1.0 and 13.8±1.5 mm. The diameter of radial tuberosty in men ranged between 15.1±1.5 and 17.7±1.8 mm; in women, it ranged between 13.2±1.1 and 15.5±1.8 mm. The mean height of the head of radius was 11.2±1.2 mm in men and 9.5±0.8 mm in women. Statistically significant sex differences were revealed in all the preceding measurements. The mean height of the neck of radius was 11.2±1.2 mm in men and 10.1±1.6 mm in women, with no significant difference (p= 0.15). The average values of morphometry of the proximal radius of the Chilean population differ from those describing the European population, and show some similarities with the Chinese population. Our results may be useful to design of implants and prostheses for the proximal radius, and to correct surgical planning in orthopedics and traumatology.

Comparative microcomputed tomographic structural analysis of the trabecular and cortical bone architecture of radius and ulna in toy dog breeds.

Radius and ulna fractures can be detected in dogs with an incidence of 18.0% and occur more frequently in toy breeds with increased complication rates. The reasons for the predisposition and the increased complication rate of antebrachial fractures in toy breeds are not yet fully understood. The aim of this study was to research the associated mechanisms by investigating the trabecular structure parameters (BV/TV (%), Tb.N (mm-1), Tb.Th (mm), Tb.Sp (mm), Conn. D (mm-3), DA) and the cortical bone density (Mean Density (mg HA/ccm)) for toy breeds and small dogs of other breeds using microcomputed tomography and to identify the differences between both groups. A total of 70 forearms, originating from toy breeds (n = 36) and small dogs of other breeds (n = 34) were evaluated by microcomputed tomography. The results of this study showed a lower bone volume fraction (BV/TV), more (Tb.N) but thinner trabeculae (Tb.Th) with greater separation (Tb.Sp) and decreased diaphyseal cortical density (Mean Density) in toy breed dogs. This could thus contribute to the increased risk of antebrachial fractures in toy breeds. Within the group of toy breeds inhomogeneous results were observed, whereby the values of the Chihuahuas deviated. This breed had significantly thinner trabeculae (Tb.Th) with a greater trabecular separation (Tb.Sp), lower bone volume fraction (BV/TV) and significantly lower diaphyseal cortical density (Mean Density). These parameters could therefore indicate an increased antebrachial fracture and complication risk, especially in Chihuahuas.

CT Based Characterization of Volar Surface of Distal Radius: Can an Ideal Volar Plate for Fixation of Distal Radial Fractures be Designed?

Background: Literature has limited evidence concerning the morphology of volar surface of distal radius. A mismatch between the plate-contour and contour of the actual volar bony surface can result in malreduction. The purpose of this study is to analyze the normal curvature morphology of volar surface of distal radius and related parameters that can help in designing of the volar plates for fixation of distal radial fractures. Methods: We retrospectively analyzed CT scans of uninjured healthy distal radii performed during a one year period (2018-2019). The mediolateral extent of the pronator quadratus line, the mediolateral curve of the pronator quadratus line, the mediolateral surface angle between intermediate column and radial column of distal radius, the curvatures and locations of their vertices for radial and intermediate columns were measured. Results: A total of 84 CT-based studies were analyzed. The mediolateral extent of the pronator quadratus line, the mediolateral curve of the pronator quadratus line, and the mediolateral surface angle between intermediate column and radial column of the distal radius were 24.27 mm, 144.8 degrees and 163.1 degrees, respectively. The mean volar curvatures of the radial and intermediate columns were 156.5 and 151.4 degrees, respectively and distances of their vertices from the pronator-quadratus line were 10.96 mm and 14.13 mm, respectively. Conclusions: Considerable variations occur in curvature morphology of distal radial volar surface. A best fit rather than an anatomical fit can be considered during implant selection owing to these variations. Besides volar curvature of radial and ulnar columns, location of their vertices, mediolateral angulation and surface curvature between these columns at the level of watershed line should also be considered in plate selection. A combination of a few serial increments of the described parameters in the designs of volar fixation plates would be helpful for surgeons in the best implant selection.

Intra-skeletal vascular density in a bipedal hopping macropod with implications for analyses of rib histology.

Human ribs are thought to be less affected by mechanical strain at the microscopic level than limb bones, implying that rib remodelling better reflects bone physiological homeostasis. Here, we test the hypothesis that rib tissue will be well vascularized and thus enhance susceptibility to metabolic influence. An intra-skeletal comparison of bone vascular canal density was conducted using a macropod animal model adapted to bipedal habitual hopping. The right humerus, ulna, radius, femur, tibia, fibula, a mid-thoracic and upper-thoracic rib of an eastern grey kangaroo (Macropus giganteus) were sectioned at the midshaft, from which histological sections were prepared. Bone vascularity from a maximum of 12 mm2 of sub-periosteal parallel-fibred and lamellar bone was recorded, resulting in a total of 2047 counted vessels. Vascular canal density data were corrected by cortical width, maximum length, and midshaft circumference robusticity indices computed for each bone. The fibula consistently had the highest vascular canal density, even when corrected for maximum length, cortical width and midshaft circumference robusticities. This was followed by the mid- and upper-thoracic ribs. Vascularity differences between bones were relatively consistent whether vascular canal density was controlled for by cortical width or midshaft circumference robusticities. Vascular canal density and robusticity indices were also positively and negatively correlated (p < 0.05). Results confirm that the ribs are well vascularized, which facilitates bone metabolic processes such as remodelling, but the fibula also appears to be a well vascularized bone. Future research investigating human bone metabolism will benefit from examining thoracic rib or fibula samples.

Bone Microarchitecture and Strength Adaptation to Physical Activity: A Within-Subject Controlled HRpQCT Study.

PURPOSE: Physical activity benefits bone mass and cortical bone size. The current study assessed the impact of chronic (≥10 yr) physical activity on trabecular microarchitectural properties and microfinite element analyses of estimated bone strength. METHODS: Female collegiate-level tennis players (n = 15; age = 20.3 ± 0.9 yr) were used as a within-subject controlled model of chronic unilateral upper-extremity physical activity. Racquet-to-nonracquet arm differences at the distal radius and radial diaphysis were assessed using high-resolution peripheral quantitative computed tomography. The distal tibia and the tibial diaphysis in both legs were also assessed, and cross-country runners (n = 15; age = 20.8 ± 1.2 yr) included as controls. RESULTS: The distal radius of the racquet arm had 11.8% (95% confidence interval [CI] = 7.9% to 15.7%) greater trabecular bone volume/tissue volume, with trabeculae that were greater in number, thickness, connectivity, and proximity to each other than that in the nonracquet arm (all P < 0.01). Combined with enhanced cortical bone properties, the microarchitectural advantages at the distal radius contributed a 18.7% (95% CI = 13.0% to 24.4%) racquet-to-nonracquet arm difference in predicted load before failure. At the radial diaphysis, predicted load to failure was 9.6% (95% CI = 6.7% to 12.6%) greater in the racquet versus nonracquet arm. There were fewer and smaller side-to-side differences at the distal tibia; however, the tibial diaphysis in the leg opposite the racquet arm was larger with a thicker cortex and had 4.4% (95% CI = 1.7% to 7.1%) greater strength than the contralateral leg. CONCLUSION: Chronically elevated physical activity enhances trabecular microarchitecture and microfinite element estimated strength, furthering observations from short-term longitudinal studies. The data also demonstrate that tennis players exhibit crossed symmetry wherein the leg opposite the racquet arm possesses enhanced tibial properties compared with in the contralateral leg.