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Objectives: The composite radial forearm flap is a surgical option in the reconstruction of large traumatic or oncologic orofacial defects. Nevertheless, it has been criticized for its poor bone transport faculties that would make this flap insufficient in large osseous mandibular reconstructions, or for oral prosthetic rehabilitation with dental implants. What is more, the morbidity of the donor site has often been pointed. The aim of this radioanatomic study was to revisit the vascularization of the composite radial forearm flap, focusing on the bone stick., Methods: A radioanatomic study was performed on seven upper limbs taken from fresh cadavers. First, the vessels were washed with a 40°C solution of potassium acetate. Then an intra-arterial injection of a mixture of lead oxide and agar-agar was performed. 3D-CT-scan examinations of the anatomical pieces were performed. In a second step, the flaps were harvested and analyzed with a Microscan examination (NanoSPECT-CT Bioscan(®), voxel 220 microns). Collateral branches of the radial artery to the bone and the skin were counted and classified., Results: One radial diaphyseal artery was present in all the cases. The nutrient foramen took place at the anteromedial aspect of the diaphysis, between 45 and 65 % of the length of the bone. A dense anastomotic periosteal network was highlightened, supplied by one to four musculoperiosteal branches, and one to six fascio-periosteal arteries arising from the radial artery. A total of mean five osseous branches, and 12 cutaneous branches have been observed., Conclusions: The results of the present preclinical study suggested that a 16-cm bone stick could be harvested with an optimal vascular safety, without consideration for the morbidity at the donor site. The original approach in this study, relating anatomy to the preclinical imaging, allowed a precise visualization of the microvascularization of the soft and hard tissues. It opened a field of innovative research in plastic and reconstructive surgery., (Copyright © 2014 Elsevier Masson SAS. All rights reserved.)

Objectives: An abnormality of the radial collateral ligament (RCL) in the setting of lateral epicondylitis can indicate a poor clinical outcome; therefore, accurate assessment is important. The purpose of this study was to characterize the proximal RCL attachment, or footprint, as seen on sonography using cadaveric dissection correlation and magnetic resonance arthrography., Methods: For the first part of this study, 4 cadaveric elbow specimens were imaged with sonography before and after dissection to characterize the RCL. After Institutional Review Board approval with consent waived, 26 consecutive magnetic resonance (MR) arthrograms of the elbow were identified. The sonograms and MR arthrograms were retrospectively reviewed to measure the length of the RCL footprint and its percentage of the combined RCL and common extensor tendon (CET) humeral footprints., Results: The mean RCL footprint length and percentage of the combined RCL and CET footprints were 8.4 mm (range, 7.4-10.0 mm) and 54% as measured from the elbow specimen sonograms and 9.1 mm (range, 6.4-12.5 mm) and 54% as measured from the MR arthrograms. The mean RCL footprint length combining data from specimens and MR arthrograms was 8.9 mm (range, 6.4-12.5 mm), covering 54% of the combined RCL and CET footprints., Conclusions: The RCL can be differentiated from the CET on sonography with knowledge of the RCL humeral footprint extent, which measured 8.9 mm in length and comprised 54% of the combined RCL and CET footprints., (© 2014 by the American Institute of Ultrasound in Medicine.)

Purpose: To determine the reliability of measuring ulnar variance on lateral wrist radiographs and to compare this technique with previously described methods., Methods: Ulnar variance was measured in 100 normal wrist radiographs using the methods of perpendiculars, central reference point, and the lateral radiograph by 3 surgeons on 2 occasions. Intraobserver repeatability and agreement between raters and methods were assessed and compared., Results: Intra- and interobserver reliability and agreement were both excellent using all 3 methods within a ± 1.0-mm cutoff. However, there was substantial pairwise disagreement in measures of ulnar variance between all 3 methods., Conclusions: This study demonstrates that, for measurement of ulnar variance, the methods of perpendiculars, central reference point, and lateral radiographic measurement each have clinically acceptable intraobserver repeatability and interobserver agreement. Despite their independent reliability, each method of radiographic determination of ulnar variance had considerable disagreement with the other methods, indicative of inherent inaccuracies in the techniques. The lateral radiograph uniquely allows for visualization of the amount of ulnar head protruding proximal or distal to the concave lunate facet and allows for a rapid estimation of pronosupination, which is known to affect ulnar variance., Clinical Relevance: Determination of ulnar variance can be an important component of surgical decision making in various pathological conditions of the hand and wrist. Traditionally, it has been measured through methods using the posteroanterior wrist radiograph, but there are potential shortcomings with these methods, and use of the lateral radiograph may provide a more clinically relevant picture of ulnar variance. This study shows that measurement from the lateral radiograph provides similar reliability to previously accepted techniques., (Copyright © 2014 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.)

The functional neutral of wrist movement is about 10° extension yet the distal radius has a volar tilt. This has not previously been explained. Assuming that the contact area between the carpus and the distal radius increased in wrist extension this would also help stabilize the carpus on the distal radius in positions where typically there is greater loading. To test this hypothesis we reconstructed three-dimensional structures of the carpal bones and distal radius using computed tomography scans of 13 normal wrists. The contact areas of the scaphoid with the distal radius were measured and were found progressively increased from flexion 20°, neutral, extension 20°, to extension 40°. The maximal increases in the contact area of the scaphoid and the distal radius was at full wrist extension. No significant changes in the contact areas of the lunate with the distal radius were found between the different positions. The contact characteristics provide greater stability to the carpus on the distal radius, and to help spread forces from impact to the wrist reducing the transmitted peak forces and thus the risk of distal radius and carpal injuries.

Purpose: This study was designed to determine whether the use of a flexible guide pin and reamer through an anterior single-incision approach would allow for a more anatomic insertion point on the radial tuberosity when compared with the traditional rigid instrumentation used for cortical button fixation., Methods: Seven matched pairs of fresh-frozen cadaveric upper extremity specimens were used in this study. One specimen from each matched pair was randomly assigned to undergo a simulated repair using the standard instrumentation required for a cortical button fixation device, and the other specimens were assigned to undergo the same repair using a 42° anterior cruciate ligament femoral guide with a flexible guide pin and reamer. Each specimen from both groups was positioned with the elbow in 90° of flexion and the forearm maximally supinated during guide pin insertion. The proximal portion of the radius was then harvested from the specimen and scanned using micro-computed tomography (micro-CT). Tunnel position between the 2 techniques was compared with the center of the native tendon footprint., Results: The mean percentage of the reamed entry hole within the tendon footprint was significantly less using rigid instrumentation (36.35%) compared with flexible instrumentation (67.29%) (P = .043). Furthermore, when flexible reamers were used (mean offset ratio, 0.17), the resultant tunnel was positioned in a significantly more central position within the radial shaft (i.e., the offset ratio was lower) compared with rigid reamers (mean offset ratio, 0.35) (P = .043). The entry hole was found to be significantly more posterior relative to the center of the anatomic footprint for the flexible reamer group (mean, 0.21 mm anterior) compared with the rigid reamer group (mean, 3.22 mm anterior) (P = .028). There was no difference in tunnel length between the 2 groups., Conclusions: The use of a flexible guide pin and reamer allows for a more anatomically positioned repair than does rigid instrumentation through a single-incision approach., Clinical Relevance: This surgical technique allows for a more anatomic re-creation of the distal biceps tendon insertion while maintaining the benefits of a single limited anterior exposure., (Copyright © 2014 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)

Background: The most widely used surgical approach to treat radial head fractures is through the Kocher interval. However, the extensor digitorum communis (EDC) splitting approach is thought to allow easier access to the anterior half of the radial head, which is more commonly fractured. The aim of this cadaveric study was to compare the osseous and articular surface areas visible through the EDC split and the Kocher interval., Methods: Four approaches were used in fresh frozen cadaveric upper extremities: EDC splitting (n = 6), modified Kocher (n = 6), extended EDC splitting (n = 6), and extended modified Kocher (n = 4). For each approach, the osseous and articular surface areas visualized were outlined with use of a burr. Each elbow was then stripped of soft tissue and a digitized three-dimensional model was created with use of a surface scanning system. The visible surface area obtained with each approach was mapped and quantified with use of the markings created with the burr., Results: The EDC splitting approach provided greater exposure of the anterior half of the radial head (median, 100%) compared with the modified Kocher approach (68%, p < 0.05). The extended modified Kocher and extended EDC splitting approaches provided comparable visualization of the distal aspect of the humerus, capitellum, radial head, and coronoid process., Conclusions: The results suggest that the EDC splitting approach provides more reliable visualization of the anterior half of the radial head while minimizing soft-tissue dissection and reducing the risk of iatrogenic injury to the lateral ulnar collateral ligament.

3D printing is an emerging technology that is primarily used for aiding the design and prototyping of implants. As this technology has evolved it has now become possible to produce functional and definitive implants manufactured using a 3D printing process. This process, however, previously required a large financial investment in complex machinery and professionals skilled in 3D product design. Our pilot study's aim was to design and create a 3D printed custom orthopaedic implant using only freely available consumer hardware and software.

Aim: For surgical treatment of unstable distal radius fractures, fixed-angled locking volar plate fixation is becoming popular nowadays because of some advantages over other surgical techniques. In this article, we discuss the fitting of fixed-angle locking volar plates to the distal radius in relation to the changes in the distal radial angles., Materials and Methods: First, we took conventional radiography images of 18 dried radii and later we measured the palmar subchondral angle, dorsal subchondral angle, mid-subchondral angle, and palmar cortical angle using lateral radiography., Results: According to the measurements, the volar subchondral angles (alpha) ranged from 10.2 degrees to 28.1 degrees, the middle subchondral angles ranged from 55.9 degrees to 93.2 degrees, the dorsal subchondral angles ranged from 77 degrees to 109.6 degrees, and the volar cortical angles ranged from 134.5 degrees to 158.4 degrees., Conclusion: Although fixed-angle locking volar plates are accepted as anatomical, our measurements showed that volar cortical angles and the subchondral angles are variable. Therefore, the term "anatomic distal radius volar plate" should be discussed.

Unlabelled: Within a normative youth cohort (16-29 years) bone parameters for males and females remained stable at the radius. At the tibia, a peak was observed for females at 16-19 years, with bone density and strength decreasing by 29 years., Purpose: To determine if bone microstructural and strength parameters identified by high-resolution peripheral quantitative computed tomography (HR-pQCT) and finite element analysis (FEA) at the distal radius and tibia, peak within the age range of this youth cohort, and whether the timing of the peaks differ based on sex or skeletal site., Methods: We recruited 251 participants (158 female; 16 to 29 years), grouping them into 5-year age brackets (16-19; 20-24; 25-29 years) assessing microstructural and strength parameters with HR-pQCT and FEA., Results: HR-pQCT assessment of males and females (age-matched groups) showed males had higher total area and BMD, trabecular BMD and trabecular number (radius only) cortical thickness and porosity, and failure load, but lower cortical BMD (p < 0.05). Within sex, microstructural and strength parameters remained stable for males, but in females they appeared to peak at 16-19 years at the tibia. Tibia bone strength and trabecular BMD were highest in females 16-19 years (p < 0.05), and tibia cortical porosity was lowest in females 16-19 years (p < 0.001). With the exception of an age-related increase in cortical BMD, all other parameters were stable between 16 and 29 years at the radius for both males and females. We found no peak values for males or females at the radius. At the tibia, a peak was observed for females 16-19 years., Conclusion: These data provide a population-based assessment of bone microstructural and strength parameters from HR-pQCT and FEA in a youth cohort, showing clear differences in bone quality dependent on sex and skeletal site.

Background: There is no validated method to determine the correct diameter of a radial head implant when the radial head is too comminuted to function as a template or during revision surgery when the radial head has been previously excised. The purpose of this study was to determine if ipsilateral capitellar dimensions could be used to predict the diameter of the radial head; and hence to assist with implant selection., Methods: Computer tomography scans of 50 normal elbows were used to generate 3D models. Measurements of the radial head included the maximum (Dmax) and minimum (Dmin) outer diameters and the maximum (Dishmax) and minimum (Dishmin) articular dish diameters. Measurements of the humerus included the width of the capitellum (CAPwidth), and the width from the lateral aspect of the capitellum to the lateral trochlear ridge (CAP-TROCHridge). Relationships were determined with Pearson bivariate coefficients., Results: The mean radial head dimensions were Dmax = 24.7 ± 2.3 mm, Dmin = 23.5 ± 2.3 mm, Dishmax = 18.2 ± 1.9 mm and Dishmin = 16.8 ± 1.7 mm. The mean capitellar measurements were CAPwidth (18.4 ± 1.4 mm) and CAP-TROCHridge (23.0 ± 2.1 mm). The most significant correlations were found between Dmax and CAP-TROCHridge (R = .90, P < .001) and Dmin and CAP-TROCHridge (R = .90, P < .001)., Discussion: Radiologic measurements of the capitellum are useful in the estimation of native radial head diameter. The CAP-TROCHridge measurement was very strongly correlated with both the maximum and minimum diameters of the radial head. This suggests that CAP-TROCHridge may be useful to accurately predict the native radial head diameter. These morphological relationships were plotted to produce an implant selection chart for radial head sizing applicable to any implant system., Level of Evidence: Basic science, anatomy study, CT imaging., (Copyright © 2013 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.)

Objective: To describe the direction and magnitude of the rotation of the radius relative to the ulna during extension of the carpus and to describe the effect of carpal extension on internal and external rotation of the radius relative to the ulna., Study Design: In vitro experiment., Animals: Cadaveric canine thoracic limbs (n = 11)., Methods: Eleven thoracic limbs were collected from 6 healthy mixed breed dogs of medium build. Each specimen was radiographed to ensure that the carpal and elbow joints were free of pathology. The elbow joint was disarticulated and the distal thoracic limb was prepared for biomechanical testing. Each specimen was stripped of soft tissue, leaving the soft tissues around the proximal aspect of the radius and ulna intact. The interosseous ligament, pronator teres muscle, and all the soft tissues distal to the distal metaphysis of the radius were also left intact. In the 1st part of the study, the rotation of the radius relative to the ulna was measured while extending the carpal joint using a system of weights and pulleys attached to the manus. In the 2nd part of the study, the internal and external rotation of the radius relative to the ulna was performed by applying an internal and external rotational load to the radius using a system of weights and pulleys attached to the radius. The internal and external rotation of the radius was measured with the carpus unloaded and with the carpus extended by applying a load of 5 kg to the manus., Results: Extension of the carpus resulted in internal rotation of the radius relative to the ulna. With the carpus extended under a maximum load of 2 kg, the mean (± SD) internal rotation of the radius was 4.3 ± 2.1° for all specimens. With the carpus unloaded, the mean internal and external rotation of the radius was 11.5 ± 2.9° and 22.5 ± 7.7° for all specimens, respectively. With the carpus loaded (extended under 5 kg load), the mean internal and external rotation of the radius was 3.3 ± 1.2° and 7.3 ± 2.0° for all specimens, respectively. The difference between internal and external rotation with the carpus loaded and unloaded was significant., Conclusion: Extending the carpus results in internal rotation, and proximal translation of the radius relative to the ulna. Loading the carpus in extension decreases the internal and external rotation of the radius relative to the ulna. A better understanding of the interaction between the carpus and the elbow may improve our understanding of the pathogenesis of elbow dysplasia., (© Copyright 2013 by The American College of Veterinary Surgeons.)

This article investigates the relationship between the cortical bone of the radius and the muscle area of the forearm. The aim of this study was to develop a method for muscle area estimation from cortical bone area at 65% of radius length where the muscle area at the forearm is largest. Muscle area and cortical area were measured directly in vivo by peripheral Quantitative Computed Tomography (pQCT). We found significant correlations between muscle area and cortical area (r = 0.881) in the forearm that are in line with previous studies. We have set up a regression model by testing relevant parameters such as age, sex, forearm length, and stature that were all highly correlated to muscle area. The influence of age and sex on the proportion of muscle area to cortical area is strong and potentially related to the effects of testosterone and estrogen on the muscle-bone-unit. Muscle area estimation from cortical bone is possible with a Percent Standard Error of Estimate (%SEE) ranging from 12.03% to 14.83%, depending on the parameters available and the age and sex of the individual. Muscle area estimation from cortical bone can provide new information for the study of skeletal and/or fossil human remains., (Copyright © 2013 Wiley Periodicals, Inc.)

African-American women have a lower risk of fracture than white women, and this difference is only partially explained by differences in dual-energy X-ray absorptiometry (DXA) areal bone mineral density (aBMD). Little is known about racial differences in skeletal microarchitecture and the consequences for bone strength. To evaluate potential factors underlying this racial difference in fracture rates, we used high-resolution peripheral quantitative computed tomography (HR-pQCT) to assess cortical and trabecular bone microarchitecture and estimate bone strength using micro-finite element analysis (µFEA) in African-American (n = 100) and white (n = 173) women participating in the Study of Women's Health Across the Nation (SWAN). African-American women had larger and denser bones than whites, with greater total area, aBMD, and total volumetric BMD (vBMD) at the radius and tibia metaphysis (p < 0.05 for all). African-Americans had greater trabecular vBMD at the radius, but higher cortical vBMD at the tibia. Cortical microarchitecture tended to show the most pronounced racial differences, with higher cortical area, thickness, and volumes in African-Americans at both skeletal sites (p < 0.05 for all), and lower cortical porosity in African-Americans at the tibia (p < 0.05). African-American women also had greater estimated bone stiffness and failure load at both the radius and tibia. Differences in skeletal microarchitecture and estimated stiffness and failure load persisted even after adjustment for DXA aBMD. The densitometric and microarchitectural predictors of failure load at the radius and tibia were the same in African-American and white women. In conclusion, differences in bone microarchitecture and density contribute to greater estimated bone strength in African-Americans and probably explain, at least in part, the lower fracture risk of African-American women., (© 2013 American Society for Bone and Mineral Research.)

Quadrupedality evolved four independent times in dinosaurs; however, the constraints associated with these transitions in limb anatomy and function remain poorly understood, in particular the evolution of forearm posture and rotational ability (i.e., active pronation and supination). Results of previous qualitative studies are inconsistent, likely due to an inability to quantitatively assess the likelihood of their conclusions. We attempt to quantify antebrachial posture and mobility using the radius bone because its morphology is distinct between extant sprawled taxa with a limited active pronation ability and parasagittal taxa that have an enhanced ability to actively pronate the manus. We used a sliding semi-landmark, outline-based geometric morphometric approach of the proximal radial head and a measurement of the angle of curvature of the radius in a sample of 189 mammals, 49 dinosaurs, 35 squamates, 16 birds, and 5 crocodilians. Our results of radial head morphology showed that quadrupedal ceratopsians, bipedal non-hadrosaurid ornithopods, and theropods had limited pronation/supination ability, and sauropodomorphs have unique radial head morphology that likely allowed limited rotational ability. However, the curvature of the radius showed that no dinosaurian clade had the ability to cross the radius about the ulna, suggesting parallel antebrachial elements for all quadrupedal dinosaurs. We conclude that the bipedal origins of all quadrupedal dinosaur clades could have allowed for greater disparity in forelimb posture than previously appreciated, and future studies on dinosaur posture should not limit their classifications to the overly simplistic extant dichotomy.

We report a systematic review and a proportion meta-analysis of prevalence studies evaluating the prevalence of palmaris longus agenesis (PLA) in the literature. The overall PLA rate was defined to be the primary outcome. Secondary outcomes were rates of PLA in relation to ethnicity, laterality, side, gender, age, and hand dominance. We identified 26 articles which met the inclusion criteria. Meta-analyses showed an overall PLA pooled rate of 20.25%, higher than the commonly reported overall rate of 15%. Our results also showed significantly lower pooled rates in Africans (11.3%) and East Asians (4.5%) when compared to Arab Middle Eastern population (41.7%). A subgroup analysis of the African group showed a pooled rate of 2.71%, the lowest, in the East and South East African population. The pooled rate was 26.3% among Caucasians, 26.16% among South and Southeast Asians and 34.13% among Turkish. In discordance with the literature, PLA was statistically more predominant on the right side. No significant differences in PLA rates were found for laterality, gender, the combination of gender and side or the combination of gender and laterality. The lowest rate of PLA found in East and South East African populations might be indicative of the subsequent phylogenetic degeneration of the palmaris longus muscle in modern humans after the "Out of Africa" migration., (Copyright © 2013 Wiley Periodicals, Inc.)

Introduction: The study of tennis players allows the nonracket arm to act as an internal control for the exercising racket arm. In addition, the study of the upper limbs removes the influence of gravitational loading, allowing the examination of the influence of muscular force on bone adaptation., Methods: The role of muscular action on bone, strength parameters of the radius, ulna (both at 4% and 60% distal-proximal ulnar length), and humerus (at 35% distal-proximal humerus length) as well as muscle size in both arms of 50 elite junior tennis players (mean ± SD age = 13.5 ± 1.9 yr) were measured with peripheral quantitative computed tomography (pQCT)., Results: Strong relationships were found between muscle size and bone size in both arms (all correlations, P < 0.001, R = 0.73-0.86). However, the muscle-bone ratio was significantly lower (P < 0.001) in the upper arm on the racket side (compared with the contralateral arm). In addition, material eccentricity analysis revealed that bone strength in bending and torsion increased more than strength in compression as the moment arms for these actions (bone length and width, respectively) increased (in all cases, P > 0.001, R = 0.06-0.7) with relationships being stronger in torsion than in bending. Large side differences were found in bone strength parameters and muscle size in all investigated sites, with differences in distal radius total BMC (+37% ± 21%) and humerus cortical cross-sectional area (+40% ± 12%) being most pronounced (both P < 0.001)., Conclusions: These results support a strong influence of muscular action on bone adaptation; however, interarm muscle-bone asymmetries suggest factors other than local muscle size that determine bone strength. The results also suggest that torsional loads provide the greatest stress experienced by the bone during a tennis stroke.

With improving clinical CT scanning technology, the accuracy of CT-based finite element (FE) models of the human skeleton may be ameliorated by an enhanced description of apparent level bone mechanical properties. Micro-finite element (μFE) modeling can be used to study the apparent elastic behavior of human cancellous bone. In this study, samples from the femur, radius and vertebral body were investigated to evaluate the predictive power of morphology-elasticity relationships and to compare them across different anatomical regions. μFE models of 701 trabecular bone cubes with a side length of 5.3 mm were analyzed using kinematic boundary conditions. Based on the FE results, four morphology-elasticity models using bone volume fraction as well as full, limited or no fabric information were calibrated for each anatomical region. The 5 parameter Zysset-Curnier model using full fabric information showed excellent predictive power with coefficients of determination ([Formula: see text]) of 0.98, 0.95 and 0.94 of the femur, radius and vertebra data, respectively, with mean total norm errors between 14 and 20%. A constant orthotropy model and a constant transverse isotropy model, where the elastic anisotropy is defined by the model parameters, yielded coefficients of determination between 0.90 and 0.98 with total norm errors between 16 and 25%. Neglecting fabric information and using an isotropic model led to [Formula: see text] between 0.73 and 0.92 with total norm errors between 38 and 49%. A comparison of the model regressions revealed minor but significant (p<0.01) differences for the fabric-elasticity model parameters calibrated for the different anatomical regions. The proposed models and identified parameters can be used in future studies to compute the apparent elastic properties of human cancellous bone for homogenized FE models.

The ability to grasp and manipulate is often considered a hallmark of hominins and associated with the evolution of their bipedal locomotion and tool use. Yet, many other mammals use their forelimbs to grasp and manipulate objects. Previous investigations have suggested that grasping may be derived from digging behaviour, arboreal locomotion or hunting behaviour. Here, we test the arboreal origin of grasping and investigate whether an arboreal lifestyle could confer a greater grasping ability in musteloid carnivorans. Moreover, we investigate the morphological adaptations related to grasping and the differences between arboreal species with different grasping abilities. We predict that if grasping is derived from an arboreal lifestyle, then the anatomical specializations of the forelimb for arboreality must be similar to those involved in grasping. We further predict that arboreal species with a well-developed manipulation ability will have articulations that facilitate radio-ulnar rotation. We use ancestral character state reconstructions of lifestyle and grasping ability to understand the evolution of both traits. Finally, we use a surface sliding semi-landmark approach capable of quantifying the articulations in their full complexity. Our results largely confirm our predictions, demonstrating that musteloids with greater grasping skills differ markedly from others in the shape of their forelimb bones. These analyses further suggest that the evolution of an arboreal lifestyle likely preceded the development of enhanced grasping ability., (© 2013 The Authors. Journal of Evolutionary Biology © 2013 European Society For Evolutionary Biology.)

This project was undertaken as part of the PhD research project of Paul Malone, Pricipal Investigator, Covance plc, Harrogate. Mr Malone approached the photography department for involvement in the study with the aim of settling the current debate on the anatomical and histological features of the distal radioulnar ligaments by capturing the anatomy photographically throughout the process of dissection via a microtome. The author was approached to lead on the photographic protocol as part of her post-graduate certificate training at Staffordshire University. High-resolution digital images of an entire human arm were required, the main area of interest being the distal radioulnar joint of the wrist. Images were to be taken at 40 μm intervals as the specimen was sliced. When microtomy was undertaken through the ligaments images were made at 20 μm intervals. A method of suspending a camera approximately 1 metre above the specimen was devised, together with the preparation for the capture, processing and storage of images. The resulting images were then to be subject to further analysis in the form of 3-Dimensional reconstruction, using computer modelling techniques and software. The possibility of merging the images with sequences obtained from both CT & MRI using image handling software is also an area of exploration, in collaboration with the University of Manchester's Visualisation Centre.

Unlabelled: In this population-based study of 24-year-old men, we have investigated the association between sport-specific exercise loading and different bone parameters. We reveal that the association between exercise loading and bone parameters is sport-specific, indicating that nonspecific resistance exercise does not impact bone density, geometry, or microstructure in young men., Introduction: In this cross-sectional study, the association between nonspecific resistive exercise and areal and volumetric bone density, bone geometry, or bone microstructure was investigated in young adult men., Methods: A total of 184 male athletes, 24.0 ± 0.6 years of age (mean ± SD), representing nonspecific resistive exercise and soccer (proportion of recreational athletes, 93.4 and 7.7 %, respectively), and 177 nonathletic age-matched controls were measured with dual-energy X-ray absorptiometry. Radius and tibia were measured by peripheral quantitative computed tomography (pQCT) at the diaphysis and by three-dimensional pQCT at the metaphysis., Results: Men in the nonspecific resistive exercise group had higher grip strength(9.1 % or 0.4 SD) and higher lean mass(5.6 % or 0.5 SD) than those in the nonathletic group(p < 0.01 and p < 0.001, respectively). However, men who participated in nonspecific resistive exercise did not have higher bone density or a more favorable bone microstructure or geometry than their nonathletic referents. In contrast, men playing soccer had higher areal bone mineral density (aBMD) at the femoral neck (19.5 % or 1.2 SD) and lumbar spine (12.6 % or 1.0 SD), as well as larger cortical cross-sectional area (16.4 % or 1.1 SD) and higher trabecular bone volume fraction (14.5 % or 0.9 SD), as a result of increased trabecular number (8.7 % or 0.6 SD) and thickness (5.7 % or 0.4 SD) at the tibia than men in the nonathletic group(p < 0.001)., Conclusions: Weight-bearing exercise with impacts from varying directions (playing soccer) is associated with aBMD and volumetric BMD, cortical bone geometry, as well as trabecular microstructure of weight-bearing bone. Nonspecific recreational resistance exercise does not appear to be a strong determinant of bone density, geometry, or microstructure in young adult men.

Background: The inferior coracoid process has traditionally been considered to be the gold standard for glenoid augmentation after anteroinferior bone loss. Other autograft sites, and more recently, osteochondral allograft sites, have been described as potential donor sources., Purpose: Potential autograft and osteochondral allograft sites were compared to identify the graft source that would provide the best fit for glenoid augmentation., Study Design: Controlled laboratory study., Methods: Mose circles, a geometric tool found on a standard goniometer, were used to make radius of curvature measurements of 10 anatomic locations in 17 cadaveric specimens. The bony surface of the glenoid, measured from superior to inferior (G-SI) and from anterior to posterior (G-AP), was used as the standard for comparison. Autograft sites were the inferior coracoid, lateral coracoid, and inner table of the iliac crest. Potential osteochondral allograft sites were the radial head, scaphoid fossa of the distal radius (S-DR), lunate fossa of the distal radius (L-DR), medial tibial plateau, and lateral distal tibia. An acceptable match for autograft sites was based on a paired analysis and defined as a radius of curvature within 5 mm of the G-SI or the G-AP of the same cadaveric specimen. Allograft sites were evaluated using an unpaired analysis in which an ideal fit was defined as a radius of curvature of 25 to 30 mm, based on the interquartile range of the G-SI and G-AP., Results: The median (interquartile range) radii of curvature for the G-SI and G-AP were 30 mm (range, 25-30 mm) and 25 mm (range, 25-25 mm), respectively. The inferior coracoid was within 5 mm of the G-SI 59% of the time and the G-AP 94% of the time; no measurements from the lateral coracoid or iliac crest were within the range of the glenoid radius of curvature. Analysis of the allograft sites demonstrated an acceptable fit for 94% of the distal tibia, 68% of the medial tibial plateau, 12% of the S-DR, and 0% of the L-DR and the radial head specimens., Conclusion: An autograft of the inferior coracoid or an osteochondral allograft of the lateral distal tibia provided the best match to re-establish the native radius of curvature of the glenoid., Clinical Relevance: To best re-create the native glenohumeral anatomy, surgeons should consider the use of an autograft of the inferior coracoid or an osteochondral allograft of the lateral distal tibia for the reconstruction of osseous glenoid defects.

Pika species generally fall into two ecotypes, meadow-dwelling (burrowing) or talus-dwelling, a classification that distinguishes a suite of different ecological, behavioral, and life history traits. Despite these differences, little morphological variation has previously been documented to distinguish among ecotypes. The aim of this study was to test whether postcranial features related to burrowing are present in meadow-dwelling species and whether talus-dwelling species exhibit postcranial modifications related to frequent leaping between rocks. To test this, the scapula, humerus, ulna, radius, innominate, femur, tibia, and calcaneus of 15 species were studied and measured. Twenty-three measurements were taken on 199 skeletons, and 19 indices were constructed from these measurements. Indices were compared between the two ecotypes using Student's t-test. Comparisons among ecotypes, species, and subgenera were made using one-way ANOVA with the Tukey honest significant difference post hoc test. Multivariate results were generated using principal components analyses. Thirteen forelimb and hind limb indices proved significant in distinguishing the meadow-dwelling, talus-dwelling, and intermediate forms. A number of these indices are associated with burrowing or leaping in other mammals, providing some support for the hypothesis that postcranial modifications in pika are related to locomotor differences. This evidence of morphological responses to ecological specialization will be useful for reconstructing the paleobiology of extinct taxa, assessing the behavioral variability of extant species, and improving our understanding of the evolutionary history of pikas., (Copyright © 2013 Wiley Periodicals, Inc.)

The distal radioulnar joint (DRUJ) is critical to the function of the forearm as a mechanical unit. This paper is concerned with the concepts and observations that have changed understanding of the function of the DRUJ, notably with respect to the biomechanics of this joint. The DRUJ has been shown to be important in acting to distribute load and removal of the ulna head leads to the biomechanical equivalent of a one-bone forearm. The soft tissues with topographical relations to the distal forearm and DRUJ have also been investigated in our experimental series with findings including the description of a clinical disorder termed subluxation-related ulna neuropathy syndrome.

Early Miocene sloths are represented by a diversity of forms ranging from 38 to 95 kg, being registered mainly from Santacrucian Age deposits in southern-most shores of Patagonia, Argentina. Their postcranial skeleton differs markedly in shape from those of their closest living relatives (arboreal forms of less than 10 kg), Bradypus and Choloepus. In order to gain insight on functional properties of the Santacrucian sloths forelimb, musculature was reconstructed and a comparative, qualitative morphofunctional analysis was performed, allowing proposing hypotheses about biological role of the limb in substrate preferences, and locomotor strategies. The anatomy of the forelimb of Santacrucian sloths resembles more closely extant anteaters such as Tamandua and Myrmecophaga, due to the robustness of the elements, development of features related to attachment of ligaments and muscles, and conservative, pentadactylous, and strong-clawed manus. The reconstructed forelimb musculature was very well developed and resembles that of extant Pilosa (especially anteaters), although retaining the basic muscular configuration of generalized mammals. This musculature allowed application of powerful forces, especially in adduction of the forelimb, flexion and extension of the antebrachium, and manual prehension. These functional properties are congruent with both climbing and digging activities, and provide support for proposed Santacrucian sloths as good climbing mammals, possibly arboreal or semiarboreal, being also capable diggers. Their climbing strategies were limited, thus these forms relied mainly on great muscular strength and curved claws of the manus to move cautiously on branches., (Copyright © 2012 Wiley Periodicals, Inc.)

Objective: While the importance of cortical structure quantification is increasingly underscored by recent literature, conventional analysis techniques obscure potentially important regional variations in cortical structure. The objective of this study was to characterize the spatial variability in cortical geometry and microstructure at the distal radius and tibia using high resolution peripheral quantitative computed tomography (HR-pQCT). We show that spatially-resolved analysis is able to identify cortical sub-regions with increased sensitivity to the effects of gender and aging., Methods: HR-pQCT scans of 146 volunteers (92 female/54 male) spanning a wide range of ages (20-78years) were analyzed. For each subject, radius and tibia scans were obtained using a clinical HR-pQCT system. Measures describing geometry (cortical bone thickness (Ct.Th)), microstructure (porosity (Ct.Po), pore diameter (Ct.Po.Dm), and pore size heterogeneity (Ct.Po.Dm SD)), and cortical bone density were calculated from the image data. Biomechanical parameters describing load and stress distribution were calculated using linear finite element analysis. Cortical quadrants were defined based on anatomic axes to quantify regional parameter variation. Subjects were categorized by gender, and age, and menopausal status for analysis., Results: Significant regional variation was found in all geometric and microstructural parameters in both the radius and tibia. In general, the radius showed more pronounced and significant variations in all parameters as compared with the tibia. At both sites, Ct.Po displayed the greatest regional variations. Correlation coefficients for Ct.Po and Ct.Th with respect to load and stress distribution provided evidence of an association between regional cortical structure and biomechanics in the tibia. Comparing women to men, differences in Ct.Po were most pronounced in the anterior quadrant of the radius (36% lower in women (p<0.01)) and the posterior quadrant of the tibia (27% lower in women (p<0.01)). Comparing elderly to young women, differences in Ct.Po were most pronounced in the lateral quadrant of the radius (328% higher in elderly women (p<0.001)) and the anterior quadrant of the tibia (433% higher in elderly women (p<0.001)). Comparing elderly to young men, the most pronounced age differences were found in the anterior radius (205% higher in elderly men, (p<0.001)) and the anterior tibia (190% higher in elderly men (p<0.01)). All subregional Ct.Po differences provided greater sensitivity to gender and age effects than those based on the global means., Conclusion: These results show significant regional variation in all geometric and microarchitectural parameters studied in both the radius and tibia. Quantification of region-specific parameters provided increased sensitivity in the analysis of age- and gender-related differences, in many cases providing statistically significant differentiation of groups where conventional global analysis failed to detect differences. These results suggest that regional analysis may be important in studies of disease and therapeutic effects, particularly where microstructural parameters based on global analyses have thus far failed to identify a response in bone quality., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Recently discovered material has yielded new information on the pectoral girdle and fin endoskeleton of Gogonasusandrewsae (Frasnian Gogo Formation, Kimberley Region, Western Australia). These elements permit the first comprehensive description of the anocleithrum, cleithrum, scapulocoracoid, and lepidotrichia. New autapomorphies of Gogonasus include a square exposed region on the supracleithrum, an unusual knob-like process on the scapulocoracoid, a relatively small entepicondyle, and lepidotrichia with I-beam-shaped cross sections. Several poorly ossified regions on the scapulocoracoid and humerus indicate an early ontogenetic state, as with other immature tetrapodomorph fish specimens. A phylogenetic analysis indicates a more stemward position for Gogonasus in a weakly supported clade with other "osteolepidid" taxa, compared to other recent studies placing Gogonasus crownward of osteolepidid fishes and the Tristichopteridae, as the sister taxon to the "Elpistosteglia" + Tetrapoda. A phylogenetic position among megalichthyid fishes is suggested for Sterropterygion, while radiographs of the megalichthyid Cladarosymblema show a scythe-like radius terminating distally with that of the intermedium. New data on the scapulocoracoid of the rhizodontid Barameda reveals a coroacoid crest and small supraglenoid foramen., (Copyright © 2012 Wiley Periodicals, Inc.)

The lateral collateral ligament (LCL) of the elbow is a complex capsuloligamentous structure critical in stabilizing the ulnohumeral and radiocapitellar articulations. LCL injury can result in elbow instability, allowing the proximal radius and ulna to externally rotate away from the humerus as a supination stress is applied to the forearm. Elbow dislocation is the most common cause of LCL injury, followed by iatrogenic injury. LCL pathology resulting in late recurrent instability is rare but disabling. The diagnosis requires a high index of suspicion, detailed history, and focused physical examination maneuvers. Stress radiographs are often the most useful imaging modality. Despite controversy over the anatomy of the LCL complex and the relative importance of its component structures, treatment of late instability is focused on lateral ligament reconstruction from the humerus to the ulna using tendon grafts with reasonably good outcomes., (Copyright © 2013 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.)

Purpose: The aim was to provide anatomical data for local blocking treatment of de Quervain's disease through investigating features and classification of the first extensor groove on the radial styloid process., Methods: Two hundred and eighty-four specimens of the intact distal extremity of dry radii from Chinese corpses were investigated and measured systematically in this study. Morphological features of the extensor grooves on the radial styloid process were observed by visual inspection. Correlation parameters of variability were measured with a vernier caliper., Results: The study showed that the most prevalent group was Type I (the extensor groove that was deep and divided into two sub-grooves by a tiny bony ridge) accounting for 63.73 % (181 specimens). Seventy-nine specimens belonged to Type II (the extensor groove without the tiny bony ridge) accounting for 27.82 % and 24 specimens belonged to Type III (almost without any extensor groove on the radius) accounting for 8.45 %. The distance between the processus of the palmar bony ridge and the processus of the dorsal bony ridge (defined as AC) was 11.55 ± 1.32 mm. The distance between the processus of the palmar bony ridge and the sharp point of the styloid process of the radius (defined as AB) was 17.09 ± 1.99 mm., Conclusions: The extensor groove could provide a subjective safe operation range for the steroid injections, which could be defined depending on the bony landmarks, which are easy to identify in the body surface. This anatomical variation is important in the management of de Quervain's disease.

The treatment of patients with distal radius fractures can be challenging and requires a thorough understanding of the condition. Many treatment options are available. The choice of treatment is based on patient factors, such as age and activity level, along with the characteristics of the fracture. It is helpful to use a case-based format to review the anatomy, the radiographic evaluation, and the initial and definitive treatment options for patients with distal radius fractures.

Distal radio-ulnar joint (DRUJ) instability is increasingly recognised and assessment can be subjective and difficult. Previous research has used cadaveric models or in-vivo with CT, with variable results. A test device was designed to establish normal values of in-vivo DRUJ dorso-palmar translation. Twenty volunteers were recruited. Those with previous wrist/forearm injuries were excluded. The device held the elbow at 90° flexion and neutral forearm rotation, with the distal ulna secured. A dorso-palmar shear force was applied to the distal radius and displacement measured three times on each wrist alternately by the same operator. The mean translation of the DRUJ is 5.5 mm. Same-sided mean measurements for two subjects taken days apart varied by 1 mm. The intra-class correlation coefficient was 0.93. The device is reliable, reproducible and appears to be a simple valid test. Contralateral sides were comparable. It will primarily be a research device to guide clinical practice in DRUJ instability.

Operative treatment of displaced and comminuted radial head fractures involves internal fixation with plates and screws in cases where reconstruction is possible and replacement with a radial head prosthesis when comminution renders the radial head unreconstructable. The purposes of this study were to evaluate the morphometry of the radial head using a modern technique and to compare the findings with several commercially available radial head prostheses. Computed tomography scans of 30 cadaveric elbows and 3-dimensional reconstructions were used to analyze the morphometry of the proximal radius. Results were compared with the manufacturer data of several radial head prostheses. Mean diameter of the radial head at the level of the fovea was 19±1.58 mm (range, 15.82-21.81 mm) in the anteroposterior plane and 18.62±1.78 mm (range, 15.48-22.21 mm) in the radioulnar plane. Mean diameter of the radial head at its widest part was 23.15±1.94 mm (range, 19.45-26.49 mm) in the anteroposterior plane and 22.44±1.73 mm (range, 19.64-25.44 mm) in the radioulnar plane. Mean diameter of the radial head at the level of the head-neck junction was 15.42±1.59 mm (range, 11.80-18.46 mm) in the anteroposterior plane and 14.75±1.39 mm (range, 12.32-17.31 mm) in the radioulnar plane. Statistically significant sex differences existed in the maximum diameter of the radial head, the diameter at the level of the head-neck junction, and the length of the radial head. Currently available radial head prostheses cover the range of sizes encountered. Products with a choice of head and stem sizes in any combination are preferable. In unstable elbow fractures, correct implant size is an important factor to avoid subluxation of the radial head (Mason type IV fractures) if collateral ligaments are sufficient., (Copyright 2013, SLACK Incorporated.)

Objective: Bone loss and periosteal expansion is found after menopause. The accelerated early postmenopausal bone loss is not permanent but if the same accounts for the periosteal expansion is unknown., Methods: Bone mineral density (BMD) and skeletal structure of the distal forearm were followed from menopause and on average 24 years (range 18-28) by single-photon absorptiometry at 12 occasions in a population-based sample of 81 Caucasian women with no medication or disease affecting bone metabolism. A Strength Index based on areal BMD and bone structure was calculated. Postmenopausal serum-estradiol levels and incident distal radius fractures were registered. Data are presented as means with 95% confidence interval (95% CI)., Results: The annual BMD loss in three periods, 0-8, 8-16 and 16-28 years after menopause, was 2.0% (1.6, 2.4), 1.0% (0.6, 1.4) and 1.0% (0.7, 1.3), respectively. The annual periosteal expansion was 1.0% (0.8, 1.3), 0.0% (-0.3, 0.3) and 0.0% (-0.2, 0.2), respectively. Mean post-menopausal oestrogen levels correlated moderately with annual loss in aBMD (r=0.51, p<0.001) but less with the annual changes in bone width (r= -0.22, p=0.06)., Conclusion: Postmenopausal periosteal expansion in the distal forearm seems to occur only in the first postmenopausal decade.

Radial inclination angle (RIA) and palmar tilt (PT) of distal articular surface of radius, are anatomical factors that influence force transmission across the wrist and load transfer to the lunate. The purpose of this study is to evaluate the relationship between these parameters and Kienböck's disease. We measured and compared RIA and PT in standard posteroanterior and lateral wrist x-rays of 55 patients with Kienböck's disease and 60 controls. The mean RIA was 25.5° in Kienböck's disease patients and 23.3° in the control group (P = .002). The mean PT was 11.5° and 9.4° for patients and controls, respectively (P = .005). All of these differences were statistically significant. We concluded that there is an etiological association between higher degrees of RIA and PT with Kienböck's disease.

Background: To describe the radial artery and its variants in origin, branching pattern, mode of termination, and measurements of its length and external diameter., Material and Methods: One hundred upper limbs of 30 men and 20 women adult cadavers were used in this study. The cadavers were obtained from the Anatomy Department, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia. The axillary region, arm, forearm, and hand of each limb were dissected to clarify the course and branches of the radial artery. This anatomical descriptive study was conducted between September 2010 and August 2012 after approval of the Ethical Committee., Results: The mean distance of the normal origin of the radial artery as one of two terminal branches of the brachial artery was 38.7 ± 9.5 mm in men and 36.5 ± 8.5 mm in the upper limbs of women below the intercondylar line, and variant origin of the radial artery was found in eight limbs. The mean of radial artery length was 226.2 ± 21.7 mm in men and 209.9 ± 13.9 mm in women and that of its external diameter was 3.3 ± 0.7 mm in men and 3.2 ± 0.66 mm in women at 1 cm distal to its origin; 3.1 ± 0.73 mm in men and 3.0 ± 0.66 in women at 2 cm proximal to the styloid process of the radius. The radial artery showed different branching patterns and three modes of termination., Conclusions: Knowledge of radial artery description and its variants has great importance in different clinical fields and basic medical studies.

The aim of this study was to investigate the development of bone mineral density (BMD) and bone mineral content (BMC) in relation to peak height velocity (PHV), and to investigate whether late normal puberty was associated with remaining low BMD and BMC in early adulthood in men. In total, 501 men (mean ± SD, 18.9 ± 0.5 years of age at baseline) were included in this 5-year longitudinal study. Areal BMD (aBMD) and BMC, volumetric BMD (vBMD) and cortical bone size were measured using dual-energy X-ray absorptiometry (DXA) and pQCT. Detailed growth and weight charts were used to calculate age at PHV, an objective assessment of pubertal timing. Age at PHV was a strong positive predictor of the increase in aBMD and BMC of the total body (R(2) aBMD 11.7%; BMC 4.3%), radius (R(2) aBMD 23.5%; BMC 22.3%), and lumbar spine (R(2) aBMD 11.9%; BMC 10.5%) between 19 and 24 years (p < 0.001). Subjects were divided into three groups according to age at PHV (early, middle, and late). Men with late puberty gained markedly more in aBMD and BMC at the total body, radius, and lumbar spine, and lost less at the femoral neck (p < 0.001) than men with early puberty. At age 24 years, no significant differences in aBMD or BMC of the lumbar spine, femoral neck, or total body were observed, whereas a deficit of 4.2% in radius aBMD, but not in BMC, was seen for men with late versus early puberty (p < 0.001). pQCT measurements of the radius at follow-up demonstrated no significant differences in bone size, whereas cortical and trabecular vBMD were 0.7% (p < 0.001) and 4.8% (p < 0.05) lower in men with late versus early puberty. In conclusion, our results demonstrate that late puberty in males was associated with a substantial catch up in aBMD and BMC in young adulthood, leaving no deficits of the lumbar spine, femoral neck, or total body at age 24 years., (Copyright © 2012 American Society for Bone and Mineral Research.)

The quantitative assessment of metabolic bone diseases relies on tissue properties such as bone mineral density (BMD) and bone microarchitecture. In spite of an increasing number of publications using high-resolution peripheral quantitative computed-tomography (HR-pQCT), the accurate and reproducible separation of cortical and trabecular bone remains challenging. In this paper, we present a novel, fully automated, threshold-independent technique for the segmentation of cortical and trabecular bone in HR-pQCT scans. This novel post-processing method is based on modeling appearance characteristics from manually annotated cases. In our experiments the algorithm automatically selected texture features with high differentiating power and trained a classifier to separate cortical and trabecular bone. From this mask, cortical thickness and tissue volume could be calculated with high accuracy. The overlap between the proposed threshold-independent segmentation tool (TIST) and manual contouring was 0.904±0.045 (Dice coefficient). In our experiments, TIST obtained higher overall accuracy in our measurements than other techniques., (Copyright © 2012. Published by Elsevier Inc.)

The purpose of this study was to assess and compare the reproducibility of trabecular bone structure measurements of the distal radius at 1.5 and 3.0 T magnetic resonance imaging (MRI). Root mean square reproducibility errors ranged from 0.69% to 4.94% at 1.5 T MRI and from 0.38% to 5.80% at 3.0 T MRI. Thus, reproducibility errors of trabecular bone structure measurements are overall in an acceptable range and similar at 1.5 and 3.0 T MRI.

Background: The proximal radius features a complex anatomy. Several studies have been published on the anatomy using different technical approaches; however, most of these studies were conducted with a special focus on parameters relevant to radial prosthetic design. The purpose of our study was to explore the complex geometry of the proximal radius with regard to fracture implant design., Methods: Our computed tomography-based measurements of 78 multiplanar reformatted radii allow for exact assessment of its geometry and offer a scientific rationale towards the design of fracture implants. We conducted measurements on the radial head, the radial neck, the radial tuberosity, the radial head-to-neck angle, and the safe zone., Results: A wide range of normal anatomy has been demonstrated for all parameters. Sex differences are statistically significant in all registered parameters, except the radial head-to-neck angle. Although measurements of maximum vs minimum radial head, neck, and tuberosity diameters show close correlation, diameter-to-length correlations, such as radial head diameter vs radial head height and radial neck diameter vs radial neck length, are low., Conclusions: Besides the wide range in size, intraindividual parameter variations have to be taken into account in the design of anatomically precontoured plates. The results of this study indicate that these plates will still need to offer the ability of "bend to match.", (Copyright © 2012 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.)

Purpose: The watershed line is a useful surgical landmark for positioning a volar locking plate. Implants placed on or distal to it can impinge on flexor tendons and cause injury. However, the details of the anatomy of this line are unclear. We studied macroscopically and histologically the structures of the volar aspect of the distal radius., Methods: We studied 20 distal forearm regions of 10 cadavers (5 males and 5 females; mean age, 79 y [range, 56-88 y]) to clarify the details of the watershed line. In 16 specimens, we investigated the macroscopic appearance of the volar aspect of the radius and the relationships among the bone, the volarradiocarpal ligaments, and the pronator quadratus. Histological analyses were performed in 4 specimens of 2 cadavers to examine the morphology of the margin of the bony structures., Results: In the medial half of the distal volar radius, 2 lines were identified by direct macroscopic visualization; one was the proximal line that corresponded to the distal ridge of the pronator fossa, and the other was the distal line, which was more prominent. A medial bony prominence was situated on the distal line. In the lateral half, the distal and proximal lines of the medial half merged to form a single line. A lateral prominence was situated on this line., Conclusions: The watershed line might not be a distinct line, and it corresponds to the distal margin of the pronator fossa in the lateral half of the volar radius and to a hypothetical line between the distal and proximal lines in the medial half. The medial and lateral bony prominences on the volar radius should be key structures for accurate plate placement to avoid flexor tendon injury., Clinical Relevance: The present study suggests bony landmarks for positioning a volar locking plate., (Copyright © 2012 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.)

The distal interosseous membrane (DIOM) of the forearm acts as a secondary stabilizer of the distal radioulnar joint (DRUJ) when the dorsal and palmar radioulnar ligaments of the triangular fibrocartilage complex are cut. Recent anatomical studies revealed that thickness of the DIOM varies widely among specimens and the distal oblique bundle (DOB) exists within the DIOM in 40% of specimens. The DOB originates from the distal one-sixth of the ulnar shaft and runs distally to insert on the inferior rim of the sigmoid notch of the radius. The mean thickness of the DIOM without a DOB was 0.4 mm, which was significantly thinner than 1.2 mm with a DOB. Biomechanical studies have shown that the DOB is an isometric stabilizer of the forearm during pronosupination. The presence of a DOB was shown to have a significant impact on DRUJ stability. Innate DRUJ laxity in the neutral forearm position was greater in the group without a DOB than in the group with a DOB. Ulnar shortening with the osteotomy performed proximal to the attachment of the DIOM had a more favorable effect on stability of the DRUJ compared with the effect of distal osteotomy, especially in the presence of a DOB. The longitudinal resistance to ulnar shortening was significantly greater in proximal shortening than in distal shortening. It also suggested that the DIOM is of great importance in the management of concomitant ulnar-side injuries in distal radius fracture., (Copyright © 2012 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.)

The discriminant power of bone volume for determining sex has not been possible to determine due to the difficulty in its calculation. At present, new advancements based on 3D technology make it possible to reproduce the bone digitally and calculate its volume using computerized tools, which opens up a new window to ascertaining the discriminant power of this variable. With this objective in mind, the tali and radii of 101 individuals (48 males and 53 females) of a contemporary Spanish reference collection (twentieth century) (EML 1) were scanned using the Picza 3D Laser Scanner. Calculated for the tali were total volume, the volume of the posterior region, which includes the posterior calcaneal facet and other three volumes of the anterior region. Calculated for the radius were total volume, volume of the radius head, volume of the diaphysis, and volume of the distal end. The data are presented for all of the variables, distinguishing between the right and left side. The data were processed using the statistical program PASW Statistics 18, thereby obtaining classification functions for sex which accurately classify 90.9 % of tali and 93.9 % of radii on the basis of their total left and right volume, respectively. Studying the volume in different regions of the bone shows that the diaphysis of the right radius possesses a high level of discriminant power, offering classification functions which accurately classify 96.9 % of the sample. The validation test performed on a sample of 20 individuals from another contemporary Spanish reference collection (EML 2) confirms the high discriminant power of the volume obtaining an accurate classification rate of 80-95 % depending on the variable studied.

Study Objectives: To determine the impact of antiandrogen treatment on bone density and geometry., Design: Prospective cohort investigation., Setting: Academic research institute., Participants: 38 (age 14.96 ± 1.42 yr) subjects with PCOS., Interventions: Treated with metformin (n = 17) or metformin and antiandrogen (n = 21)., Main Outcome Measure: Bone density and geometry parameters at baseline and after a mean duration of 1.92 ± 0.88 years using peripheral quantitative computed tomography of the forearm., Results: At baseline, z-scores for trabecular (0.53 ± 1.02) and cortical BMD (0.79 ± 1.55) as well as total (0.62 ± 1.07) and medullary cross sectional area (CSA) (0.79 ± 1.29) were elevated. Cortical CSA (-0.01 ± 1.10) and bone strength strain index (SSI) z-scores (-0.01 ± 1.10) were normal. Muscle CSA z-score (0.12 ± 1.70) was normal, but grip strength (-1.60 ± 1.15) was significantly reduced. There were no significant changes within and between the two treatment options in respect to bone density and bone geometry parameters. With antiandrogen treatment, free androgen index (FAI) was significantly lower and grip strength further decreased (P < .001)., Conclusions: No significant changes in bone mineral density and geometry parameters took place in PCOS women irrespective of treatment followed over a time of almost two years. General muscle weakness expressed as low grip strength may influence further bone development in PCOS., (Copyright © 2012 North American Society for Pediatric and Adolescent Gynecology. Published by Elsevier Inc. All rights reserved.)

As a source of corticocancellous grafts for treating scaphoid nonunions, the anterolateral corner of the distal radial metaphysis has several advantages over other alternatives: it provides good-quality corticocancellous bone, it allows one to harvest the graft and treat the scaphoid through the same incision, it does not require general anesthesia, and it has less morbidity than occurs when obtaining the graft from the iliac crest., (Copyright © 2012. Published by Elsevier Inc.)

The distal radioulnar joint (DRUJ) is a complex articulation allowing significant rotational and translational motion. Stability of the DRUJ depends on bony contact, intrinsic stabilizers of the triangular fibrocartilage complex, and extrinsic stabilizers of the distal forearm. Understanding the anatomy of this articulation is paramount in clinical decision making for the treatment of disorders involving the DRUJ., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Background/aim: The task of a forensic examiner during exhumation of skeletal remains is to calculate antemortem height of a person whose skeletal remains were found. Anthropological investigations which provided formulae for calculating ante-mortem body height date back from XIX or from the first half of XX centuries. The most commonly used formulae are those of Trotter-Gleser, which were used to investigate skeletal remains from the World War II. Those investigations were conducted on skeletal remains of various ages and degrees of decay. Our experience with exhumation have shown that the present formulae do not deliver reliable values of antemortem height. The aim of this study was to investigate if there is a correlation of the length of long bones of leg and forearm with body height within our population and to establish the formulae for calculating ante-mortem body height within our population based on the obtained values., Methods: The lengths of ulna, radius, fibula and tibia were determined precisely by measuring bones on living individuals using a digital X-ray system. The height of individuals whose bones were measured was determined using an anthropometer., Results: The highest degree of correlation between bone length and body height was found for tibia in males (r = 0.859, p < 0.005) and ulna in females (r = 0.679, p < 0.05). We calculated the regression formulae for determination of ante-mortem body height that differ from the current body height formulae., Conclusion: In our population the length of long bones of the forearm and the leg are characterized by various degree of correlation with body height. The formulae that we set, make less distinction between the measured and the calculated body height as compared with the Trotter-Gleser formulae. We do hope that their implementation will facilitate identification of sceletal remains in our population.

Purpose: We evaluated site-specific skeletal adaptation to loading during growth, comparing radius (RAD) and femoral neck (FN) DXA scans in young female gymnasts (GYM) and non-gymnasts (NON)., Methods: Subjects from an ongoing longitudinal study (8-26yr old) underwent annual DXA scans (proximal femur, forearm, total body) and anthropometry, completing maturity and physical activity questionnaires. This cross-sectional analysis used the most recent data meeting the following criteria: gynecological age ≤2.5yr post-menarche; and GYM annual mean gymnastic exposure ≥5.0h/wk in the prior year. Bone geometric and strength indices were derived from scans for 173 subjects (8-17yr old) via hip structural analysis (femoral narrow neck, NN) and similar radius formulae (1/3 and Ultradistal (UD)). Maturity was coded as M1 (Tanner I breast), M2 (pre-menarche, ≥Tanner II breast) or M3 (post-menarche). ANOVA and chi square compared descriptive data. Two factor ANCOVA adjusted for age, height, total body non-bone lean mass and percent body fat; significance was tested for main effects and interactions between gymnastic exposure and maturity., Results: At the distal radius, GYM means were significantly greater than NON means for all variables (p<0.05). At the proximal femur, GYM exhibited narrower periosteal and endosteal dimensions, but greater indices of cortical thickness, BMC, aBMD and section modulus, with lower buckling ratio (p<0.05). However, significant interactions between maturity and loading were detected for the following: 1) FN bone mineral content (BMC) and NN buckling ratio (GYM BMC advantages only in M1 and M3; for BMC and buckling ratio, M1 advantages were greatest); 2) 1/3 radius BMC, width, endosteal diameter, cortical cross-sectional area, and section modulus (GYM advantages primarily post-menarche); and 3) UD radius BMC and axial compressive strength (GYM advantages were larger with greater maturity, greatest post-menarche)., Conclusions: Maturity-specific comparisons suggested site-specific skeletal adaptation to loading during growth, with greater advantages at the radius versus the proximal femur. At the radius, GYM advantages included greater bone width, cortical cross-sectional area and cortical thickness; in contrast, at the femoral neck, GYM bone tissue cross-sectional area and cortical thickness were greater, but bone width was narrower than in NON. Future longitudinal analyses will evaluate putative maturity-specific differences., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Objective: Measurement of anthropometric parameters of long bones can be applied in sex determination and height prediction. The aim of this study was to investigate the value of length of the radius in forensic identification., Materials and Methods: Cross-sectional analysis of anthropometric parameters of the radius was done by Legal Medicine Organization of Tehran, Iran studying fresh cadavers of Iranian population during 2009 and 2010., Results: This study surveyed length of radius of 106 fresh Iranian cadavers, 61 men and 45 women, in the age range of 10-85 years old. The study showed that genders can be distinguished using the length of radius with a sensitivity of 83% and specificity of 96%. Using the regression test, there was significant relation between the height of persons and the length of radius bone. The equations were obtained to estimate the height of the individuals on the basis of radius bone length in different age groups, with an exception in females of 40-64 Years old., Conclusion: In the cases of fresh cadavers, by using the length of radius, we could be able to determine the length of height and gender with high confidence., (Copyright © 2012 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.)

Purpose: In fractures of the radial head and neck requiring open reduction and internal fixation, osteosynthesis may be safely applied in a limited zone. We conducted a morphometric study of the proximal radius at the level of the safe zone to identify different morphologic types of this anatomical region., Methods: We analyzed 44 dried cadaveric radii. We measured the whole length of the radius, the length of the neck and head, and the minimum and maximum diameter of the radial head. The morphologic aspect of the neck-head curvature of the safe zone was evaluated qualitatively and quantitatively., Results: The proximal radius at the level of the safe zone exhibited different radii of bending. In particular, we identified a morphologic type A, which showed a flat profile (25% of cases), morphologic types B and C, which showed a low concave curvature (64%), and a marked concave curvature (11%), respectively, of the safe zone., Conclusions: The profile of the proximal radius in the safe zone shows substantial morphologic variations that should be taken into account when operating on fractures of the proximal radius, to avoid malunions, pain, and stiffness of the elbow joint. A preoperative radiograph of the contralateral uninjured radius may be helpful in selecting the most appropriate internal fixation device to reconstruct the proximal radius after comminuted fractures., Clinical Relevance: Knowledge of the proper bending radius of the safe zone allows the surgeon to select the most appropriate plate, and to achieve good fracture reduction and anatomical restoration of the proximal radius., (Copyright © 2012 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.)

Purpose: The aim of the study was to investigate possible linear intra-bone geometry dependencies by determining the relation between the maximum radius length and maximum distal width in two independent populations and test for possible gender or age effects. A strong correlation can help develop more representative fracture models and osteosynthetic devices as well as aid gender and height estimation in anthropologic/forensic cases., Methods: First, maximum radius length and distal width of 100 consecutive patients, aged 20-70 years, were digitally measured on standard lower arm radiographs by two independent investigators. Second, the same measurements were performed ex vivo on a second cohort, 135 isolated, formalin fixed radii. Standard descriptive statistics as well as correlations were calculated and possible gender age influences tested for both populations separately., Results: The radiographic dataset resulted in a correlation of radius length and width of r=0.753 (adj. R(2)=0.563, p<0.001) with sex having a significant (p=0.005, adj. R(2)=0.592) and side no influence on the correlation. Radius length-width correlation for the isolated radii was r=0.621 (adj. R(2)=0.381, p<0.001) with sex significantly influencing this correlation (p<0.001, adj. R(2)=0.598)., Conclusion: A relatively strong radius length-distal width correlation was found in two different populations, indicating that linear body proportions might not only apply to body height and axial length measurements of long bones but also to proportional dependency of bone shapes in general., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

There is scant morphological data for equine carpal bones despite the frequent pathology in Thoroughbreds (TB). This study aimed to identify morphological and morphometrical variations and similarities in carpal bones between and within TB and Ponies (Po). Carpal bones from nine TB and 13 Po were prepared by boiling and drying. Lateromedial width, dorsopalmar depth, proximodistal height, relative density and volume of each bone were measured. Normalized measurements of the radial (Cr) and third (C3) carpal bones were significantly different in all dimensions, and there were significant variations in relative sizes of articular facets of the ulnar (Cu), C3 and fourth (C4) carpal bones between the groups. Bilaterally, the proportionate volume of the intermediate carpal bone (Ci) was significantly greater in Po while that of Cu and C4 were significantly greater in TB. Relative density of most bones was greater in Po. The palmar tuberosity of the proximal surface of Ci and palmar tubercle on the palmar surface of Cu were more prominent and relatively larger in TB. In the second carpal bone (C2), the distal extent of the proximal articular surface on the palmar surface was greater in Po. The inconsistent first carpal bone (C1) was relatively larger in Po. Morphometrical similarities and differences in carpal bones between TB and Po indicate potential effects of selection for body size or fast exercise., (© 2011 Blackwell Verlag GmbH.)