Humeral Length Research Articles

A Second Specimen ofCitipati OsmolskaeAssociated With a Nest of Eggs from Ukhaa Tolgod, Omnogov Aimag, Mongolia

Adult dinosaurs preserved attending their nests in brooding positions are among the rarest vertebrate fossils. By far the most common occurrences are members of the dinosaur group Oviraptorosauria. The first finds of these were specimens recovered from the Djadokhta Formation at the Mongolian locality of Ukhaa Tolgod and the Chinese locality of Bayan Mandahu. Since the initial discovery of these specimens, a few more occurrences of nesting oviraptors have been found at other Asian localities.Here we report on a second nesting oviraptorid specimen (IGM 100/1004) sitting in a brooding position atop a nest of eggs from Ukhaa Tolgod, Omnogov, Mongolia. This is a large specimen of the ubiquitous Ukhaa Tolgod taxon Citipati osmolskae. It is approximately 11% larger based on humeral length than the original Ukhaa Tolgod nesting Citipati osmolskae specimen (IGM 100/979), yet eggshell structure and egg arrangement are identical. No evidence for colonial breeding of these animals has been recovered.Reexamination of another “nesting” oviraptorosaur, the holotype of Oviraptor philoceratops (AMNH FARB 6517) indicates that in addition to the numerous partial eggs associated with the original skeleton that originally led to its referral as a protoceratopsian predator, there are the remains of a tiny theropod. This hind limb can be provisionally assigned to Oviraptoridae. It is thus at least possible that some of the eggs associated with the holotype had hatched and the perinates had not left the nest.

Improving precision of second-trimester biometry.

To utilise image score-based criteria for second-trimester fetal biometry as an educational tool to improve biometry quality. Five sonographers regularly performing obstetric ultrasound examinations were recruited for this study. Biometry images were collected from fifteen second-trimester examinations for each sonographer prior to participating in a biometry education session, and another set of biometry images were collected from fifteen second-trimester examinations following the education session. The education session was a one-hour presentation that explained image score-based criteria to evaluate and grade the quality of the bi-parietal diameter (BPD), head circumference (HC), abdominal circumference (AC), femur length (FL) and humeral length (HL) biometry parameters. Each of the five sonographers performed a total of 30 examinations (15 pre- and 15 post-education session). From these examinations, a total of 150 images were collected for each biometry parameter (75 pre- and 75 post-education). A total of 600 biometry images were evaluated. Images from both the pre- and post-education session were assessed by an obstetrician sonologist using the same image score-based criteria. Pre- and post-image scores were compared using paired t-tests. Improvement in the mean image scores for all biometry parameters was observed after the education session. The difference between pre- and post-education image quality scores was significant for the AC (P = 0.01), FL (P = 0.002) and for the overall score (P = 0.001). Implementing an image score-based criteria evaluation technique is a simple and useful method to improve fetal biometry precision.

A mixed model for the relationship between latitude and human post‐cranial form

The general adherence of modern human body proportions to ecogeographic rules is frequently argued to be the result of thermoregulatory adaptation to climate. However, much of the history of human migrations follows the same clines that are associated with trends in body form. It is therefore important to test hypotheses about human adaptation to climate with approaches that account for population history and structure.In this project, we investigate the relationship between latitude and post‐cranial form in modern humans, with the goal of accounting for population history/structure and providing estimates of effects sizes and error. Using a multivariate quantitative genetics mixed model, we estimate morphological effects associated with latitude for long bone lengths and body size using osteometric data from 121 globally‐distributed populations and geographically matched genetic data representing 28 populations. The model includes a random effect for population structure (genetic relatedness) and a fixed effect for latitude. We found that among‐group variation was tightly correlated between limb lengths and body size measures respectively, but that these trait groups were fairly independent of each other. In addition, only bi‐iliac breadth demonstrates a clear directional effect once population history is taken into consideration, though directional trends skew positive for humeral length and negative for distal limb lengths, supporting previous research.By disentangling latitudinal effects from population structure using a mixed model approach, we add to the growing body of research exploring these strong underlying associations, and allow for a better understanding of the relationship between environmental and post‐cranial morphological diversity.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Reconstructing Locomotor Behaviors: Cross‐sectional Property Analysis Brings More to the Story of How Earliest Euprimates Moved

As a group, modern primates demonstrate an impressive degree of ecological and behavioral flexibility. It is likely that the earliest euprimates were similarly diverse in how they moved through their environments. Attempts to reconstruct the locomotor behaviors of Eocene primates have relied heavily on comparing the external morphologies of fossilized limb bones with those of extant taxa. Though broadly informative, the application of this method may be limited by the phylogenetic constraints associated with bone length and articular surface size and shape. Alternatively, the internal structure of a long bone's diaphysis is functionally plastic during life, responding to changes in loading behaviors. Therefore, diaphyseal cross‐sectional shape analyses may provide a more accurate account of how that individual actually moved. We apply this technique to a sample of ~54.5 million year old euprimates from Vastan Lignite Mine, India. This sample of fossils falls within 2 clades of Eocene euprimates, Omomyidae and Adapoidea, and represents at least 3 described genera.Our unpaired fossil sample of 6 femora (2 Asiadapis, 2 Marcgodinotius, 2 Vastanomys) and 4 humeri (2 probable Marcgodinotius, 2 unidentified euprimates) was compared with 20 species of extant prosimians (< 1 kilogram), spanning 3 locomotor classifications (leapers, slow climbers, and non‐specialists). Vastan specimens were scanned using a Nikon XT H 225 ST micro x‐ray computed tomography (CT) scanner. From these scans, diaphyseal cross‐sectional geometric properties were calculated at 50% of femoral length and 40% of humeral length (from distal end) using MomentMacro for ImageJ, which calculates polar second moment of area (J), second moments of area about the coronal (Ix) and sagittal (Iy) planes, cortical area (CA), and total subperiosteal area (TA). Each fossil was compared to the distributions of the prosimian locomotor groups for each of the cross‐sectional properties, as well as bone length and proximal articular surface areas (estimated from linear measurements).Results of structural analyses include an unusual mosaic of locomotor indicators. The relative thickness of bone cortices (CA/TA) is high in all humeri, which is best matched among modern slow climbers. Humeri are moderately long relative to humeral head articular surface area, similar to extant slow climbers and non‐specialists. Cross‐sectional shape (Ix/Iy) of femora is variable, with the adapoids (Asiadapis and Marcgodinotius) mostly grouping with leapers and non‐specialists, while the omomyids (Vastanomys) group with slow climbers, in contrast to inferences based on some other aspects of femoral articular morphology. Femoral length relative to bending rigidity (J) or femoral head surface area is moderate to high, primarily overlapping with extant leapers and non‐specialists. These results illustrate a combination of features not found in modern prosimians and may demonstrate a unique generalist regime of movement in our earliest antecedents.Support or Funding InformationNational Geographic and Leakey FoundationThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Allograft-Prosthetic Composite Reconstruction for Massive Proximal Humeral Bone Loss in Reverse Shoulder Arthroplasty.

Allograft-prosthetic composite (APC) reconstruction of the humerus represents an appealing surgical technique when implantation of a reverse prosthesis is considered in the setting of substantial proximal humeral bone loss1-4. Humeral APCs have been successfully performed in the past with a non-reverse shoulder prosthesis4,5. Reconstruction of the proximal part of the humerus with an allograft provides adequate support and fixation for the humeral component, allows restoration of length and lateral offset, and provides an opportunity for soft-tissue reattachment when needed. On the basis of the available peer-reviewed data, healing at the allograft-host junction is reliable, and complication rates, including instability, are relatively low3,6. Once the glenoid reverse component has been implanted, a proximal humeral allograft is prepared to receive the humeral component of a reverse arthroplasty. The allograft is procured by our institutional bone and tissue bank, purchased from a number of vendors. The graft is selected after review of the description and radiographs provided by the vendor. The priority is to obtain a graft with sufficient length and soft tissues attached. If possible, the graft selected should have a diameter close to the diameter of the humerus of the recipient. The desired allograft length is selected on the basis of preoperative planning and intraoperative measurements, and the distal portion of the allograft is resected accordingly. Depending on the length of the defect, host bone quality, and surgeon preferences, the humeral component may or may not bypass the host-graft junction. The stem bypasses the host-graft junction for shorter APCs, as well as when the bone quality of the native humerus is compromised. Cemented fixation into the graft is universally used. Compression plating is used for graft-to-host fixation, supplemented by implantation of the stem across the junction in selected cases. Care is taken during the freehand cut to obtain optimal contact and compression. Once the ideal humeral bearing thickness has been selected, the polyethylene bearing is implanted and the joint relocated. If the posterior cuff can be repaired to cuff allograft, sutures are placed prior to relocation and are tied after relocation. Other musculotendinous units, such as the deltoid or pectoralis major, are repaired to the allograft if needed. Implantation of a reverse prosthesis with a proximal humeral metal body (a so-called tumor prosthesis) is the main alternative to proximal humeral APC reconstruction. In patients with shorter defects, adequate soft-tissue tension may be obtained by implanting a glenosphere with a large inferior eccentricity and cementing the humeral component in a more proximal position than is usually performed. Alternatively, when implantation of the glenoid component of a reverse prosthesis is not possible, a hemiarthroplasty-APC construct may be performed1,4,5,7-10, adding a synthetic sleeve such as an aortic Dacron graft to enhance soft-tissue stability if needed. When reverse arthroplasty is performed in the setting of substantial humeral bone loss, the humeral component may be poorly supported and at risk for loosening. In addition, the absence of proximal humeral bone stock may lead to shortening and/or loss of lateral offset. Finally, the posterosuperior cuff, subscapularis, deltoid, and pectoralis tendons may remain detached. The potential consequences of humeral bone loss in the setting of reverse arthroplasty include humeral loosening, dislocation, and poor active motion (particularly poor active elevation). Allograft reconstruction of the proximal part of the humerus provides an opportunity for better support of the component, restoration of humeral length and lateral offset, and attachment sites for the musculotendinous structures around the shoulder, if needed.

What is the best glenoid configuration in onlay reverse shoulder arthroplasty?

The purpose of this study was to analyze the effect of different glenoid configurations on arm position and range of motion (ROM) following reverse shoulder arthroplasty (RSA). The hypothesis was that different glenoid configurations would lead to changes in humeral offset, acromio-humeral distance (AHD), ROM, and rotator cuff muscle length. Using a three-dimensional (3D) computer model, implantation of an RSA was simulated with a 145° onlay humeral stem combined with five different glenoid configurations which varied in diameter and centre of rotation. Glenoid offset, the AHD, ROM, and muscle length were evaluated for each configuration. Changing glenoid design led to up to a 10mm change in offset and a 3mm change in the AHD. There was 7° of improvement in abduction and flexion between the different glenoid designs. Two of the configurations, the 36mm centered and the BIO-RSA, had an adduction deficit. In extension and external rotation arm with the arm at side, the eccentric 36mm glenosphere was the best configuration while the centered 36mm glenosphere was the worst configuration. The 42mm glenosphere limited external rotation at 90° of abduction. Varying the glenosphere configurations leads to ROM and muscle length changes following RSA. With a 145° onlay humeral stem, a 36 eccentric glenosphere theoretically optimizes ROM while limiting scapular notching.

Danger zone of radial nerve in Indian population – A cadaveric study

BackgroundIdentification of the radial nerve is necessary during surgery of the humerus fracture to avoid injury to it. Iatrogenic nerve injury during humerus fracture surgery is a well-known complication. Prevention of this type of injuries would be of great value. Aim of this study is to reduce the chance of iatrogenic nerve injury by defining of a danger zone in the distal upper arm regarding the radial nerve in indian population. MethodsThirty six upper limbs of eighteen adult human formalin preserved cadavers (14 males & 4 females) were used in this study. The posterior aspect of the arm was dissected to expose the radial nerve from the triangular space to the point where the radial nerve pierced the lateral intermuscular septum. Systematic identification of radial nerve and multiple measurements were done for each specimen. ResultsThe mean humeral length was 30.96 + 1.23 cm. Mean Distance of medial epicondyle to entry of radial nerve into spiral groove was 18.5 + 0.79 cm. Mean Distance of lateral epicondyle to exit of radial nerve into spiral groove was 11.34 + 0.41 cm. The mean length of radial nerve groove/spiral groove was 4.3 + 0.75 cm. ConclusionsOur study has identified the point of intersection of radial nerve to humerus in Indian population. Understanding the safe zones and the zone of danger of the humerus provides more safety during the surgical interference of the humerus. To do this, the radial nerve must be identified and protected. Wide incision and blunt dissection is still recommended to minimize the risk of radial nerve damage.

Asymmetry in the Cortical and Trabecular Bone of the Human Humerus During Development.

Many studies have noted that the bones of the human upper limb display bilateral asymmetry, commonly linking this asymmetry in external and internal morphology to handedness and lateralization. Few studies, however, have attempted to track asymmetry throughout ontogeny. This study assesses the ontogenetic development of cortical and trabecular bone asymmetry in the humerus. We predict that directional asymmetry in structural properties will emerge in concert with hand preference and increased activity levels during the juvenile period. Paired humeri from 57 individuals from the Norris Farms #36 archaeological skeletal collection ranging in age from neonate to adult were used in the current study. Cortical bone cross-sectional properties and three-dimensional trabecular bone structure were quantified from microcomputed tomography data. The results indicate significant absolute asymmetry in all measured cortical and trabecular bone variables across all ages. Trabecular bone displays significantly higher absolute asymmetry than cortical bone. Contrary to expectations, however, this study found very little evidence for significant directional asymmetry in humeral length and cortical or trabecular bone variables, except in adults. The presence of significant absolute asymmetry in all age groups, and the lack of significant directional asymmetry in almost all variables at all ages, suggests that structural differences due to higher levels of habitual loading in the dominant arm are overlain on a template of potentially significant existing asymmetry. Anat Rec, 301:1012-1025, 2018. © 2017 Wiley Periodicals, Inc.

Morphology and structure of Homo erectus humeri from Zhoukoudian, Locality 1.

BackgroundRegional diversity in the morphology of the H. erectus postcranium is not broadly documented, in part, because of the paucity of Asian sites preserving postcranial fossils. Yet, such an understanding of the initial hominin taxon to spread throughout multiple regions of the world is fundamental to documenting the adaptive responses to selective forces operating during this period of human evolution.MethodsThe current study reports the first humeral rigidity and strength properties of East Asian H. erectus and places its diaphyseal robusticity into broader regional and temporal contexts. We estimate true cross-sectional properties of Zhoukoudian Humerus II and quantify new diaphyseal properties of Humerus III using high resolution computed tomography. Comparative data for African H. erectus and Eurasian Late Pleistocene H. sapiens were assembled, and new data were generated from two modern Chinese populations.ResultsDifferences between East Asian and African H. erectus were inconsistently expressed in humeral cortical thickness. In contrast, East Asian H. erectus appears to exhibit greater humeral robusticity compared to African H. erectus when standardizing diaphyseal properties by the product of estimated body mass and humeral length. East Asian H. erectus humeri typically differed less in standardized properties from those of side-matched Late Pleistocene hominins (e.g., Neanderthals and more recent Upper Paleolithic modern humans) than did African H. erectus, and often fell in the lower range of Late Pleistocene humeral rigidity or strength properties.DiscussionQuantitative comparisons indicate that regional variability in humeral midshaft robusticity may characterize H. erectus to a greater extent than presently recognized. This may suggest a temporal difference within H. erectus, or possibly different ecogeographical trends and/or upper limb loading patterns across the taxon. Both discovery and analysis of more adult H. erectus humeri are critical to further evaluating and potentially distinguishing between these possibilities.

The Circle-Fit Method Helps Make Reliable Cortical Thickness Measurements Regardless of Humeral Length.

Background:Although proximal humerus strength/quality can be assessed using cortical thickness measurements (eg, cortical index), there is no agreement where to make them. Tingart and coworkers used measurements where the proximal endosteum becomes parallel, while Mather and coworkers used measurements where the periosteum becomes parallel. The new circle-fit method (CFM) makes 2 metaphyseal (M1-M2) and 6 diaphyseal (D1-D6) measurements referenced from humeral head diameter (HHD). However, it is unknown whether these locations correlate to humeral length (HL). Accordingly, we asked: (1) Does HHD, Tingart distance, and Mather distance correlate with HL? (2) What is the location of HHD, Tingart distance, and Mather distance as a percentage of HL? and (3) Which CFM D1-D6 locations correlate with Tingart and Mather distances?Materials and Methods:Measurements made on cortical thickness (CT) scout views of 19 humeri (ages: 16-73 years) included HHD, distances from the superior aspect of the humerus to proximal Tingart and Mather locations, and HL.Results:Intraclass correlation was excellent for CFM-HHD, poor for Tingart, and moderate for Mather. The CFM-HHD had a stronger correlation to HL than Tingart and Mather. Mean HHD was 15.5% (0.9%) of HL while Tingart was 27.0% (4.1%) and Mather was 23.2% (3.8%). Tingart distance corresponded to D2/D3 CFM locations while the Mather distance was similar to D1/D2.Discussion:The CFM reliably correlates with HL and provides a stronger correlation and less variance between specimens than the Tingart or Mather Methods.Conclusions:Because the CFM produces reliable percent of HL locations, it should be used to define locations for obtaining biomechanically relevant CT measurements such as cortical index. Stronger correlations of these CFM-based measurements with proximal humerus strength will be important for developing advanced algorithms for fracture treatment.

Humeral lengthening using a retrograde motorized intramedullary lengthening nail

An elite-level 13-year-old female overhead athlete, with a previous history of bone cyst and fracture at age 8, presented with a humeral length discrepancy of 75 mm which had increased to 81 mm within 1 year. Antegrade correction with a motorized lengthening nail was considered but declined due to risk of shoulder damage and pain. In an off-label manner, a femoral motorized lengthening nail was modified and utilized with retrograde placement. Lengthening instructions were modified weekly to account for rapid humeral growth, to minimize soft-tissue tension, and to maximize regenerate quality. By 11 weeks, humeral length was clinically corrected. Three weeks after ceasing lengthening, full range of motion of the shoulder and elbow returned. Once the site had formed new cortex on all four sides, the nail was removed, and return to full activity occurred 4 months later.

Allograft-Prosthetic Composite Reconstruction for Massive Proximal Humeral Bone Loss in Reverse Shoulder Arthroplasty.

Reverse total shoulder arthroplasty (RTSA) performed in the setting of massive proximal humeral bone loss often requires special reconstructive techniques. Restoration of the proximal part of the humerus with an allograft provides a number of theoretical benefits, including implant support, restoration of humeral length, deltoid tensioning, and an opportunity to repair the posterior aspect of the cuff to improve strength in external rotation and repair of the subscapularis to improve stability. However, reverse allograft-prosthesis composites (APCs) are costly, are technically demanding to use, and can be compromised by progressive allograft resorption. Between 2005 and 2012, the lead author used an APC reconstruction in 8 primary and 18 revision RTSAs (26 patients; mean age, 62 years; mean body mass index, 27.9 kg/m). The indications for the primary RTSAs included severe proximal humeral bone loss after trauma (n = 5) and tumor resection (n = 3). The indications in the revision setting were failed hemiarthroplasty (n = 11), anatomic total shoulder arthroplasty (n = 4), and reverse arthroplasty (n = 3). The most common reason for revision was instability (n = 10). A compression plate was used for graft-to-host fixation in all shoulders. Shoulders were assessed for pain, motion, American Shoulder and Elbow Surgeons (ASES) score, Simple Shoulder Test (SST) score, Neer score, revision or reoperation, radiographic evidence of graft union or resorption, and implant fixation. The mean duration of follow-up was 4 years (range, 2 to 10 years). RTSA using an APC construct resulted in substantial improvements in pain scores (p < 0.0001), elevation (p < 0.0001), and external rotation (p = 0.004). With the numbers available, there were no significant differences in clinical outcomes between primary and revision cases. No patients required revision surgery for nonunion at the host-allograft junction. The mean time to union was 7 months, with 1 patient requiring bone-grafting for delayed union. Other complications included dislocation, deep infection, graft fracture, and periprosthetic fracture distal to the previous APC construct in 1 patient each. The 2 and 5-year revision-free survival rate was 96%. Reconstruction of proximal humeral bone loss with an APC at the time of primary or revision RTSA is safe and effective, with acceptable functional outcomes and complication rates. Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Transhumeral loading during advanced upper extremity activities of daily living.

Percutaneous osseointegrated (OI) implants for direct skeletal attachment of upper extremity prosthetics represent an alternative to traditional socket suspension that may yield improved patient function and satisfaction. This is especially true in high-level, transhumeral amputees where prosthetic fitting is challenging and abandonment rates remain high. However, maintaining mechanical integrity of the bone-implant interface is crucial for safe clinical introduction of this technology. The collection of population data on the transhumeral loading environment will aid in the design of compliance and overload protection devices that mitigate the risk of periprosthetic fracture. We collected marker-based upper extremity kinematic data from non-amputee volunteers during advanced activities of daily living (AADLs) that applied dynamic loading to the humerus. Inverse dynamic analysis was applied to calculate the axial force, bending and torsional moments at three virtual amputation levels representing 25, 50, and 75% residual humeral length. The influences of amputation level, elbow flexion constraint, gender and anthropometric scaling were assessed. Results indicate that the proximal (25%) amputation level experienced significantly higher axial forces and bending moments across all subjects when compared to distal amputation levels (p≤0.030). Constraining elbow flexion had a limited influence on peak transhumeral loads. Male subjects experienced higher axial forces during all evaluated activities (p≤0.023). Peak axial force for all activities occurred during jumping jacks (174.5N). Peak bending (57.6Nm) and torsional (57.2Nm) moments occurred during jumping jacks and rapid internal humeral rotation, respectively. Calculated loads fall within the range of implant fixation failure loads reported in cadaveric investigations of humeral stem fixation; indicating that periprosthetic fracture may occur during non-contact AADLs. These kinematic data, collected over a range of AADLs, will aid in the development of overload protection devices and appropriate post-operative rehabilitation protocols that balance return to an active lifestyle with patient safety.

Sexual Dimorphism and Estimation of Height from Body Length Anthropometric Parameters among the Hausa Ethnic Group of Nigeria

The study was carried out to investigate the sexual dimorphism in length and other anthropometric parameters. To also generate formulae for height estimation using anthropometric measurements of some length parameters among Hausa ethnic group of Kaduna State, Nigeria. A cross sectional study was conducted and a total of 500 subjects participated in this study which was mainly secondary school students between the age ranges of 16-27 years, anthropometric measurements were obtained using standard protocols. It was observed that there was significant sexual dimorphism in all the parameters except for body mass index. In all the parameters males tend to have significantly (P < 0.05) higher mean values except biaxillary distances. Height showed positive and strongest correlations with demispan length, followed by knee height, thigh length, sitting height, hand length, foot length, humeral length, forearm length and weight respectively. There were weak and positive correlations between height and neck length as well as biaxillary length. The demi span length showed the strongest correlation coefficient and low standard error of estimate indicating the strong estimation ability than other parameters. The combination of two parameters tends to give better estimations and low standard error of estimates, so also combining the three parameters gives better estimations with a lower standard error of estimates. The better correlation coefficient was also observed with the double and triple parameters respectively. Male Hausa tend to have larger body proportion compared to female. Height showed positive and strongest correlations with demispan length. Body length anthropometric proved to be useful in estimation of stature among Hausa ethnic group of Kaduna state Nigeria.

A Novel Registration-Based Approach for 3D Assessment of Posttraumatic Distal Humeral Deformities.

With current 3-dimensional (3D) computer-based methods for the assessment of deformities, a surface registration method is applied to superimpose a computer model of the pathological bone onto a mirrored computer model of the contralateral side. However, because of bilateral differences, especially in humeral torsion, such template-based approaches may introduce bias in the assessment of a distal humeral deformity. We hypothesized that a novel registration approach might prove superior to the current approach in reducing such bias, thus yielding improved accuracy of 3D assessment of distal humeral deformities. Three-dimensional triangular surface models were generated from computed tomographic (CT) data of 100 paired humeri without a pathological condition. Humeral segments of varying, predetermined lengths, excluding the distal part of the humerus, were defined. A surface registration algorithm was applied to superimpose the humeral models of both sides based on each selected segment. Humeral contralateral registration (HCR) errors, defined as the residual differences in apparent 3D orientation between the distal parts, were evaluated. The mean HCR error (and standard deviation) using the distal-most humeral shaft segment to assess the angular orientation was 2.3° ± 1.1 (range, 0.5° to 5.8°). Including the humeral head in the surface registration algorithm, however, as is done currently, resulted in a higher HCR error (p < 0.001). The HCR error using the proximal-most segment was >10° in 20% of the cases and between 5° and 10° in an additional 50% of the cases. By comparison, using the proposed distal-most humeral shaft segment, the HCR error was between 5° and 10° in only 2% of cases, and was never >10°. The proximal segments are nevertheless used in the proposed method for registering humeral length. The proposed new approach yields a deformity assessment that is less prone to bias arising from inherent bilateral differences and therefore is more accurate than current surface registration approaches. Accurate 3D assessment is of fundamental importance if computer-based methods are applied in the correction of posttraumatic deformities.

Cadaveric Analysis of Proximal Humerus Locking Plate Fit: Contour Mismatch May Lead to Malreduction.

To investigate proximal humerus locking plate fit in a large sample of human proximal humeri. A total of 97 cadaveric human humeri were selected. Humerus length, head diameter, and neck-shaft angle were measured. Three-hole and 5-hole 3.5-mm proximal humerus locking compression plates were affixed. A digital caliper was used to measure the maximum gap distance from the plate to the bone. Analysis of variance and student's t tests were conducted to evaluate differences in plate-bone distance between the 2 plate lengths, gender, race, age, and laterality. Correlation between plate-bone distance and humerus length, head diameter, and neck-shaft angle were determined. Mean plate-bone distance for the 3-hole plate was 1.5 ± 0.6 mm (range 0.3-2.9 mm), and for the 5-hole plate was 2.5 ± 0.9 mm (range 0.7-5.0 mm) (P = 0.01). Female and right-sided humeri were shown to have significantly larger plate-bone gap distance when compared with counterparts (P = 0.01). No correlation was found between plate-bone gap distance and humeral length (R = 0.03), head diameter (R = 0.05), or neck-shaft angle (R = 0.08). The proximal humerus locking plate was under-contoured and spanned all 97 specimens. Greater plate-bone distance was observed with the 5-hole plate versus the 3-hole plate. Applying the plate flush to bone may lead to medial displacement of the humeral head at the calcar increasing risk of loss of fracture fixation. In fractures with any metaphyseal comminution, malreduction will be more pronounced. Caution should be exercised when using the proximal humerus locking plate as a reduction aide.

Relación anatómica del abordaje posterior de húmero mínimamente invasivo con el nervio radial. Un estudio descriptivo en cadáveres

BackgroundIt is well known that the various minimally invasive approaches described improve outcomes for the surgical fixation of diaphyseal humerus fractures. However, there is a lack of information between the anatomical relationship of the radial nerve for the required incisions or for the position of the plate when a posterior approach is used. The objective of the study is to describe the anatomical relationship of the radial nerve with both incisions of the posterior minimally invasive approach, and with the distal tip of the osteosynthesis plate. Materials and methodsA descriptive study was performed on cadavers without trauma of upper limbs, in prone with 45° of abduction of shoulder and 90° of elbow flexion. After sliding a plate of 2.7 mm, the distances of the radial nerve with respect to the reference points of the approach and distal tip of the plate were recorded in millimetres. ResultsA mean humeral length of 286.6 mm was found. The mean distance from the lateral epicondyle to the radial nerve was 155.1 mm. The mean distance from the tricipital aponeurosis to the radial nerve was 138.9 mm, and from the distal tip of the plate to the radial nerve was 155.6 mm. DiscussionPlate fixation using minimal invasive technique using a posterior surgical approach may be safe for diaphyseal fractures of the humerus with respect to radial nerve injuries, as long as the plate screws are located outside the range of 128.5 mm to 169.5 mm measured from the tip of the plate. Clinical studies are required to demonstrate the safety of this approach. Evidence levelIV.

Is the pectoralis major tendon a reliable reference for restoration of humeral length with fracture hemiarthroplasty?

The primary objective was to calculate and to apply the numeric value of the distance from the pectoralis major tendon insertion to the superior aspect of the humeral head (PMTD) without any radiation exposure or equipment through basic data such as age, sex, height, and weight of Asian populations. We analyzed shoulder magnetic resonance images of 260 patients (107 men and 153 women; average age, 59.8 years). The superior border of the pectoralis major was identified on the transverse section and cross-referenced with the coronal section. Measurements were made inferiorly from the corresponding transverse section to the top of the humeral head superiorly in coronal view. Correlation analysis was performed between variables including the patient's age, sex, height, weight, and body mass index and the PMTD by multiple linear regression analysis. The mean PMTD was 52 mm, with an average of 55 mm for men and 49 mm for women. Sex and height were significantly correlated with PMTD. The PMTD increased to a consistent level proportionally to height, and the difference in PMTD between men and women was 3.45 mm. An equation to estimate PMTD using these findings is as follows: PMTD (in mm) = 23 + (height [cm] × 0.17) + 3.45 (the last number is added for men). This equation had a prediction error of 0.3 mm. Our study demonstrated that PMTD is a useful and reliable reference for optimal humeral height during hemiarthroplasty for proximal humerus fractures in Asian populations.

An anthropometric survey of US pre-term and full-term neonates

Background: Anthropometric data prove valuable for screening and monitoring various medical conditions. In young infants, however, only weight, length and head circumference are represented in publicly accessible databases.Aim: To characterise length and circumferential measures in pre-term and full-term infants up to 90 days post-natal.Subjects and methods: In eight US medical centres, trained raters recorded humeral, ulnar, femoral, tibial and fibular lengths along with mid-upper arm, mid-thigh, chest, abdominal and neck circumference. Data were pooled by post-menstrual age into 1-week intervals and population curves created using the lambda, mu and sigma (LMS) method. Goodness-of-fit was assessed by examining de-trended quantile-quantile plots, Q statistics and fitted centiles overlaid on empirical centiles.Results: In total, 2097 infants were enrolled in this study with a mean ± SD gestational age and post-natal age of 37.1 ± 3.3 weeks and 27.3 ± 25.3 days, respectively. A re-scale option was used to describe all curves. The resultant models reliably characterised anthropometric measures from 33–52 weeks PMA, with less certainty at the extremes (27–55 weeks).Conclusion: The population curves generated under this investigation expand existing reference data on a comprehensive set of anthropometric traits in infants through the first 90 days post-natal.

A preliminary anthropometric study of height and sex determination using percutaneous humeral and tibial lengths

Height, age and sex determination from different bones of the body are helpful for establishing the identity of an individual. In developed countries, established osteometric data exist for height and sex determination. However, very little information is available on the use of osteometric indices for forensic and biometric purposes in Ghana. Therefore, the aim of this study was to determine height and sex of participants using percutaneous humeral and tibial lengths. One hundred undergraduate students were recruited from the Kwame Nkrumah University of Science and Technology with 55% males and 45% females aged between 18 and 43 years for the study. Male participants had longer humeri and tibiae than females (p < 0.05). In both male and female participants, right humeri were slightly longer than the left, and left tibiae were slightly longer than the right, but these differences were not statistically significant. Mean humeral and tibial lengths of the study population differed significantly from those reported for Indians, Nigerians, Turks and Iranians. Tibial length was a better estimator of osteometric index for height and left humeral length was the only sexually dimorphic parameter, making these indices useful tools for preliminary height and sex determination.