Analysis of Radiographic Parameters of Sagittal Spinopelvic Alignment: Polish Nomenclature and Clinical Implications

Over the last 30 years, many authors have suggested that the shape of the human spine in the sagittal plane is helpful in understanding its physiology and pathology. This paper presents the current views and Polish no-men-clature used for the assessment of the morphology and position of the pelvis in the sagittal plane. The va-lues of particular radiographic parameters are presented for healthy individuals and for patients with selected spinal pathologies. Moreover, the paper discusses the practical application of the radiographic parameters that describe the shape and position of the pelvis in the sagittal plane.

Evaluating macroscopic sex estimation methods using genetically sexed archaeological material: The medieval skeletal collection from St John's Divinity School, Cambridge

OBJECTIVES

In tests on known individuals macroscopic sex estimation has between 70% and 98% accuracy. However, materials used to create and test these methods are overwhelming modern. As sexual dimorphism is dependent on multiple factors, it is unclear whether macroscopic methods have similar success on earlier materials, which differ in lifestyle and nutrition. This research aims to assess the accuracy of commonly used traits by comparing macroscopic sex estimates to genetic sex in medieval English material.

MATERIALS AND METHODS

Sixty-six individuals from the 13th to 16th century Hospital of St John the Evangelist, Cambridge, were assessed. Genetic sex was determined using a shotgun approach. Eighteen skeletal traits were examined, and macroscopic sex estimates were derived from the os coxae, skull, and os coxae and skull combined. Each trait was tested for accuracy to explore sex estimates errors.

RESULTS

The combined estimate (97.7%) outperformed the os coxae only estimate (95.7%), which outperformed the skull only estimate (90.4%). Accuracy rates for individual traits varied: Phenice traits were most accurate, whereas supraorbital margins, frontal bossing, and gonial flaring were least accurate. The preauricular sulcus and arc compose showed a bias in accuracy between sexes.

DISCUSSION

Macroscopic sex estimates are accurate when applied to medieval material from Cambridge. However, low trait accuracy rates may relate to differences in dimorphism between the method derivative sample and the St John's collection. Given the sex bias, the preauricular sulcus, frontal bossing, and arc compose should be reconsidered as appropriate traits for sex estimation for this group.

Morphometric Measurements of the Hip Bone in Turkish Adult Population

OBJECTIVES

Coxal bone paticipates in the formation of the pelvic skeleton. Anatomy knowledge on coxafemoral joint as well as careful history taking and physical examination are crucial in evaluation and management of disorders involving hip joint. The aims of the present study were to perform morphometric measurements of the human coxal bones, calculation of their articular surface areas and report the range of these parameters regarding Turkish adult population.

METHODS

Seventy-two dry human adult coxal bones (39 left and 33 right) from the Anatomy Departments of Erciyes University, Inonu University and Kahramanmaras Sutcu Imam University were measured using a caliper sensitive to 0.1 mm. Morphometric measurements were performed through 22 parameters determined. While 19 of these parameters were related to the distance between two points and thicknesses in various parts of the bone, the remaining three were related to the determination of articular surface areas. The articular surface areas of hip bone (facies auricularis (FA), facies lunata (FL) and facies symphsialis (FS)) were calculated with ImageJ software program.

RESULTS

The average values of facies auricularis area were 1659.04 ± 470.92 mm² and 1637.32 ± 460.15 mm² on the left and right coxal bones, respectively. No statistically significant difference was determined between the left and right coxal bone measurements (p > 0.05). We found a positive and significant correlation between articular surface areas of facies auricularis (FA), facies lunata (FL) and facies symphysialis (FS) and maximum width of ilium (rFA = 0.299, rFL = 0.276, rFS = 0.375, respectively and p < 0.05), and distance between spina ilica anterior superior and the upper edge of facies symphysialis (rFA = 0.268, rFL = 0.511, rFS = 0.482, respectively and p < 0.05).

CONCLUSION

The distribution and mean values of coxal bone morphometric measurements usually differ between individuals and human populations. With this regard, orthopedic surgeons should be aware of the diversity in components of coxal bone dimensions although implants and hip prosthesis components of different sizes are manufactured. Safe routes and estimated distances should be considered during surgical procedures to avoid complications.

Minimally invasive anterior pelvic internal fixation: An anatomic study comparing Pelvic Bridge to INFIX

OBJECTIVES

Anterior external fixation for pelvic ring fractures has shown to effectively improve stability and reduce mortality. However, these fixators can be associated with substantial morbidity such as pin tract infection, premature loss of fixation, and decreased quality of life in patients. Recently, two new methods of subcutaneous anterior pelvic internal fixation have been developed; the INFIX and the Pelvic Bridge. These methods have the purported advantages of lower wound complications, less surgical site pain, and improved quality of life. We sought to investigate the measured distances to critical anatomic structures, as well as the qualitative and topographic differences notable during implantation of both devices in the same cadaveric specimen.

MATERIALS AND METHODS

The Pelvic Bridge and INFIX were implanted in eleven fresh cadavers. Distances were then measured to: the superficial inguinal ring, round ligament, spermatic cord, lateral femoral cutaneous nerve (LFCN), femoral nerve, femoral artery, and femoral vein. Observations regarding implantation and topography were also recorded.

RESULTS

The INFIX had greater measured distances from all structures except for the LFCN, in which its proximity placed this structure at risk. Neither device appears to put other critical structures at risk in the supine position. Significant implantation and topographic differences exist between the devices. The INFIX application lacked "safety margins" concerning the LFCN in 10/11 (90.9%) specimens, while Pelvic Bridge placement lacked "safety margins" with regard to the right superficial ring (1/11, 9%) and the right spermatic cord (1/11, 9%).

CONCLUSIONS

Both the Pelvic Bridge and INFIX lie at safe distances from most critical pelvic structures in the supine position, though INFIX application places the LFCN at risk.

[Design of Minimal Invasive Screw on Posterior Pelvis Ring and Pelvic Finite Element Analysis]

OBJECTIVE

To design minimal invasive screw on posterior pelvic ring and perform threedimensional finite element analysis based on a pelvis finite element model.

METHODS

We measured the pelvic anatomical data of 20 healthy volunteers and identified potential designs for minimal invasive screw on posterior pelvic ring. A finite element model of pelvis was then established. Threedimensional finite element analyses were performed under static and dynamic mechanical loading,respectively.

RESULTS

Three screw tracks on ilium (A,B and C) were identified based on a threedimensional reconstruction of pelvis. Nail track B and C had greater length and width,but shorter distance between nailing and soft tissue compared with nail track A. Static loading under an external rotation load of 500 N generated a maximum Mises Von stress of 582.05 Pa and sacral iliac complex of 107.38 Pa. The greatest strain was located at the articular cartilage on the side of the nail,followed by lateral sacral joint cartilage and symphysis pubis. The largest displacement was located at the ilium on the side of the nail,with a gradient decrease to the opposite side. The largest displacement of the anterior superior iliac spine was 0.35 cm on the side of the nail. The dynamic loading identified displacement of the anterior superior iliac spine with 1.5 mm in Z axis,1.8 mm in X axis and -0.2 mm in Y axis; and displacement of the pubic bone with 0.8 mm in Z axis,1.0 mm in X axis and 0.03 mm in Y axis. The maximum displacement appeared along the impact direction: Y axis. Relatively large equivalent stress was found in pubis and ischium,anterior superior iliac spine,sacrum,acetabular that are prone to fracture. With increased impact force,the stress of pelvis increased over time. The maximum impact force,stress and displacement of the pelvis occurred at 10 ms when peak force was reached. Under the impact of 4 000 N and 5 000 N,the bone was subject to a stress level of over 200 MPa,exceeding its average yield strength,which suggests a possibility of pelvic fracture.

CONCLUSION

Taking B/C as a main screw track and A as an auxiliary screw track is a reasonable choice. The pelvic finite element model lays a foundation for further studies into sacral fracture and design of screw tracks.

The auricular surface as age indicator in a modern Greek sample: A test of two qualitative methods

The auricular surface is often found very well preserved, thus age-related changes in this anatomical area can be important for any set of human remains that require identification under different taphonomic conditions. This study tests the Buckberry and Chamberlain (2002) and Schmitt et al. (2005) methods in predicting the age of individuals in a documented sample from Crete, Greece. Both methods were used to record changes on the auricular surface in a mixed-sex sample of 74 individuals, directly as well as through photographs, by two independent observers. Cohen's kappa and intra class correlation coefficients (ICC) were used in order to assess inter-observer and intra-observer agreement. Results showed than none of the methods predicted age with sufficient accuracy, as high error rates were recorded. The Schmitt et al. (2005) method performed better, mainly because the age ranges it uses are broader. Scoring through photographs does not seem to introduce bias in predicting age, as demonstrated by the high intra-observer agreement rates. Inter-observer agreement was also high. The low intra- and inter-observer error rates suggest that the poor performance of both methods in the Cretan sample is not due to a lack of clarity in the description of the morphological changes recorded on the auricular surface; rather it should be attributed to a poor correlation between these changes and age at death in our material.

Anatomy, taphonomy, and phylogenetic implications of a new specimen of Eolambia caroljonesa (Dinosauria: Ornithopoda) from the Cedar Mountain Formation, Utah, USA

Background

Eolambia caroljonesa is the most abundant dinosaur in the lower Cenomanian Mussentuchit Member of the Cedar Mountain Formation of Utah, and one of the most completely known non-hadrosaurid iguanodontians from North America. In addition to the large holotype and paratype partial skulls, copious remains of skeletally immature individuals, including three bonebeds, have been referred to E. caroljonesa. Nevertheless, aspects of the postcranial anatomy of this taxon, particularly the pelvic girdle, have remained ambiguous due to the lack of associated postcranial material of larger, more mature individuals.

Methodology/Principal findings

Here we describe a recently discovered associated partial postcranial skeleton of a large Eolambia caroljonesa. This specimen, FMNH PR 3847, provides new anatomical data regarding the vertebral column and pelvic girdle, supplementing previous diagnoses and descriptions of E. caroljonesa. A new phylogenetic analysis incorporating information from FMNH PR 3847 places E. caroljonesa as a basal hadrosauromorph closely related to Protohadros byrdi from the Cenomanian Woodbine Formation of Texas. Histological analysis of FMNH PR 3847 reveals that it represents a subadult individual eight to nine years of age. Taphonomic analysis indicates that FMNH PR 3847 was preserved in a crevasse splay deposit, along with an unusual abundance of small crocodylomorph material.

Conclusions/Significance

FMNH PR 3847 provides a wealth of new morphological data, adding to the anatomical and systematic characterization of Eolambia caroljonesa, and histological data, revealing new information on growth history in a basal hadrosauromorph. Taphonomic characterization of FMNH PR 3847 and associated vertebrate material will allow comparison with other vertebrate localities in the Mussentuchit Member of the Cedar Mountain Formation.

The Human Pelvis: Variation in Structure and Function During Gait

The shift to habitual bipedalism 4-6 million years ago in the hominin lineage created a morphologically and functionally different human pelvis compared to our closest living relatives, the chimpanzees. Evolutionary changes to the shape of the pelvis were necessary for the transition to habitual bipedalism in humans. These changes in the bony anatomy resulted in an altered role of muscle function, influencing bipedal gait. Additionally, there are normal sex-specific variations in the pelvis as well as abnormal variations in the acetabulum. During gait, the pelvis moves in the three planes to produce smooth and efficient motion. Subtle sex-specific differences in these motions may facilitate economical gait despite differences in pelvic structure. The motions of the pelvis and hip may also be altered in the presence of abnormal acetabular structure, especially with acetabular dysplasia. Anat Rec, 300:633-642, 2017. © 2017 Wiley Periodicals, Inc.

Insertion of psoas minor tendon at pelvic brim, a novel anatomic landmark for extra-articular, screw placement through Stoppa approach

BACKGROUND

The psoas minor partially inserted to the superior pelvic brim. And the plate used to fix the acetabular fracture has always been positioned at the pelvic brim after reduction through the Stoppa approach. However, there are few studies depicting the clinical significance of the psoas minor. The purpose of this paper was to explore the relationship between the insertion of the psoas minor tendon at the pelvic brim (IPMTPB) and screw placement through the Stoppa approach.

MATERIALS AND METHODS

Fifteen cadavers were dissected for adequate exposure to IPMTPB in our study. However, not all specimens had a psoas minor. For the specimens with IPMTPB, the posterior and anterior edges were used as the first and second entry points, dividing the area from the sacroiliac joint to the pubic symphysis into three zones (d1, d2 and d3). The average proportion of each zone was obtained after measurement the three zones, to locate the two entry points for the specimens without a psoas minor. From the longitudinal Stoppa incision, the first wire was inserted horizontally, and the second wire was placed vertical to the bone surface. Fluoroscopy and computed tomography (CT) were conducted to examine the relationship between the wires and the acetabulum.

RESULTS

There was a psoas minor in sixteen hemipelvises (53.33%). After measurement and calculation, we determined that the average proportions of zones d1, d2, and d3 were 28.03%, 29.14%, and 42.83%, respectively. For all specimens, the wires were successfully inserted, and the trajectories of the wires were outside the hip joint cavity.

CONCLUSIONS

IPMTPB could be used as an anatomic landmark of safe zones for screw placement through the Stoppa approach. For cases without a psoas minor, the zones for extra-articular screw placement could be determined through the measurements in this paper.

Gender determination from diagnostic factors on anteroposterior pelvic radiographs

BACKGROUND

Gender determination from skeletal remains is one of the primary factors in forensic medicine. This study aimed to identify the gender of patients referred to the radiology ward of the Rasoul Akram Hospital of Tehran using anteroposterior pelvic radiography.

METHODS

A total of 200 patients (100 male and 100 female) referred to the radiology ward of the Rasoul Akram Hospital for anteroposterior pelvic radiography during 2013-2014 were included in this study. After taking a standard radiographic image of all patients in the supine position and an anteroposterior view of the pelvis, factors including subpubic angles, pubic angle, X angle, ischiopubic index, ratio of the length of the symphysis pubis to the mid and minimum width of the pubis body, and ratio of the length of the symphysis pubis to the minimum width of the pubic superior ramus were measured on radiographs. The Student t test and receiver operating characteristic curve were used to compare the data of male and female patients. Values were significant at p<0.05.

RESULTS

All the evaluated variables were significantly different in male and female patients (p=0.000), with the highest level of measurement accuracy noted in the subpubic angle, Pubic Angle 1, X angle, Pubic Angle 2, minimum width of the pubic superior ramus, and ischiopubic index. Length of the symphysis pubis, length of the pubis, and ratio of the length of the pubis to the minimum width of the pubic superior ramus showed the lowest accuracy.

CONCLUSION

The results of this study revealed that the evaluation of the radiographic images of pelvic bones by assessing the mentioned factors can be useful for sex determination from skeletal remains. However, ethical considerations should also be taken into account while using these factors.

Mechanism of labour - the interaction between the maternal pelvis and fetal skull

This article considers the anatomy and physiology underpinning the mechanism of labour in terms of the amazing journey the fetus completes through the maternal pelvis. In order to monitor maternal and fetal wellbeing and promote progress in labour, the midwife needs a thorough understanding of: the maternal pelvis, the external structure of the fetal skull, and how the presentation and attitude of the fetus determines the presenting diameter of the skull.

[The emergence of obstetrical mechanism: From Lucy to Homo sapiens]

The evolutionary history of modern birth mechanism is now a renewed interest in obstetrical papers. The purpose of this work is to review the literature in paleo-obstetrical field. Our analysis focuses on paleo-obstetrical hypothesis, from 1960 to the present day, based on the reconstruction of fossil pelvis. Indeed, these pelvic reconstructions usually provide an opportunity to make an obstetrical assumption in our ancestors. In this analysis, we show that modern birth mechanism takes place during the emergence of our genus 2 million years ago. References are made to human specificities related to obstetrical mechanism: exclusive bipedalism, increase of brain size at birth, metabolic cost of the pregnancy and deep trophoblastic implantation.

A New Ophthalmosaurid (Ichthyosauria) from Svalbard, Norway, and Evolution of the Ichthyopterygian Pelvic Girdle

In spite of a fossil record spanning over 150 million years, pelvic girdle evolution in Ichthyopterygia is poorly known. Here, we examine pelvic girdle size relationships using quantitative methods and new ophthalmosaurid material from the Slottsmøya Member Lagerstätte of Svalbard, Norway. One of these new specimens, which preserves the most complete ichthyosaur pelvic girdle from the Cretaceous, is described herein as a new taxon, Keilhauia nui gen. et sp. nov. It represents the most complete Berriasian ichthyosaur known and the youngest yet described from the Slottsmøya Member. It is diagnosed on the basis of two autapomorphies from the pelvic girdle, including an ilium that is anteroposteriorly expanded at its dorsal end and an ischiopubis that is shorter or subequal in length to the femur, as well as a unique character combination. The Slottsmøya Member Lagerstätte ichthyosaurs are significant in that they represent a diverse assemblage of ophthalmosaurids that existed immediately preceding and across the Jurassic–Cretaceous boundary. They also exhibit considerable variation in pelvic girdle morphology, and expand the known range in size variation of pelvic girdle elements in the clade.

Influence of pelvic postural angle change on acetabulum implantation in total hip arthroplasty

The current study investigated the relationship between the implantation angle of the acetabular component and the change in the pelvic postural angle during hip arthroplasty surgery. One pelvis with a left lower limb prosthesis was used. Total hip arthroplasty on the left pelvis was simulated with the help of a computer-assisted navigation system. The pelvis revolved around the horizontal, longitudinal and sagittal axes at different angles, and the anteversion and abduction of the acetabular component were measured. The changing angle of the pelvis rotating around the horizontal and longitudinal axes greatly influenced acetabular component anteversion. The changing angle of the pelvis rotating around the sagittal axis had a relatively great influence on the acetabular component abduction angle. The change in the postural angle of the pelvis had a great influence on the installation angle of the acetabular component. It is important to standardize posture prior to the operation.

Normative values of spino-pelvic sagittal alignment, balance, age, and health-related quality of life in a cohort of healthy adult subjects

PURPOSE

To elucidate the normative values of whole body sagittal alignment and balance of a healthy population in the standing position; and to clarify the relationship among the alignment, balance, health-related quality of life (HRQOL), and age.

METHODS

Healthy Japanese adult volunteers [n = 126, mean age 39.4 years (20-69), M/F = 30/96] with no history of spinal disease were enrolled in a cross-sectional cohort study. The Oswestry Disability Index (ODI) questionnaire was administered and subjects were scanned from the center of the acoustic meati (CAM) to the feet while standing on a force plate to determine the gravity line (GL), and the distance between CAM and GL (CAM-GL) was measured in the sagittal plane. Standard X-ray parameters were measured from the head to the lower extremities. ODI was compared among age groups stratified by decade. Correlations were investigated by simple linear regression analysis. Ideal lumbar lordosis was investigated using the least squares method.

RESULTS

The present study yielded normative values for whole standing sagittal alignment including head and lower extremities in a cohort of 126 healthy adult volunteers, comparable to previous reports and thus a formula for ideal lumbar lordosis was deduced: LL = 32.9 + 0.60 × PI - 0.23 × age. There was a tendency of positive correlation between McGregor slope, thoracic kyphosis, PT, and age. SVA, T1 pelvic angle, sacrofemoral angle, knee flexion angle, and ankle flexion angle, but not CAM-GL, increased with age, suggesting that the spinopelvic alignment changes with age, but standing whole body alignment is compensated for to preserve a horizontal gaze. ODI tended to increase from the 40s in the domain of pain intensity, personal care, traveling, and total score. ODI weakly, but significantly positively correlated with age and PI-LL.

CONCLUSION

Whole body standing alignment even in healthy subjects gradually deteriorates with age, but is compensated to preserve a horizontal gaze. HRQOL is also affected by aging and spinopelvic malalignment.

Management of Pelvic Ring Injuries in Unstable Patients

High-energy pelvic ring injuries can represent life-threatening injuries in the polytraumatized patient, particularly when presenting with hemodynamic instability. These injuries mandate a systematic multidisciplinary approach to evaluation, and timely intervention to address hemorrhage while concomitantly addressing mechanical instability. These pelvic injuries are associated with potentially lethal hemorrhage originating from venous, arterial, and osseous sources. A thorough understanding of anatomy, radiographic findings, and initial physical examination can alert one to the presence of pelvic instability necessitating emergent treatment. The focus is on hemorrhage control, using techniques for skeletal stabilization, angiography, and open procedures to decrease mortality in this high-risk patient population.

The Influence of Serum Uric Acid on Bone Mineral Density, Hip Geometry, and Fracture Risk: The Rotterdam Study

CONTEXT

The role of uric acid (UA) in skeletal metabolism remains to be unraveled.

OBJECTIVE

We prospectively investigated the association between UA, bone mineral density at the femoral neck (FN-BMD), hip bone geometry parameters, and incident fracture risk and examined whether the associations were modified by age and vitamin C intake.

PARTICIPANTS AND SETTING

Data of 5074 participants of The Rotterdam Study, a prospective population-based cohort.

EXPOSURE

Serum UA was assessed at baseline.

MAIN OUTCOMES AND MEASURES

FN-BMD was measured at baseline, and at second, third, and fourth visits of the Rotterdam Study. Hip bone geometry parameters were measured at baseline and at the second and third visits.

RESULTS

Serum UA levels (per SD increase) were positively associated with FN-BMD (β = 0.007 g/cm(2); 95% confidence interval [CI] = 0.002-0.01), thicker cortices (β = 0.002 cm; 95% CI = 0.0003-0.002), lower bone width (β = -0.013 cm; 95% CI = -0.23 to -0.003), and lower cortical buckling ratio (β = -0.19; 95% CI = -0.33 to -0.06). The effects of UA on FN-BMD and cortical buckling ratio tended to become stronger over time. Hazard ratios and 95% CIs per SD increase of baseline UA levels for the development of any type of incident fractures, nonvertebral fractures, and osteoporotic fractures were 0.932 (0.86-0.995), 0.924 (0.856-0.998), and 0.905 (0.849-0.982), respectively. These associations were more prominent in older individuals (age, >65 y) and in participants with high intakes of vitamin C (> median).

CONCLUSIONS

Higher levels of serum UA are associated with higher BMD (at the expense of thicker cortices and narrower bone diameters) and may be a protective factor in bone metabolism. However, interactions with age and vitamin C may be present.

Prostate contours delineation using interactive directional active contours model and parametric shape prior model

Prostate contours delineation on Magnetic Resonance (MR) images is a challenging and important task in medical imaging with applications of guiding biopsy, surgery and therapy. While a fully automated method is highly desired for this application, it can be a very difficult task due to the structure and surrounding tissues of the prostate gland. Traditional active contours-based delineation algorithms are typically quite successful for piecewise constant images. Nevertheless, when MR images have diffuse edges or multiple similar objects (e.g. bladder close to prostate) within close proximity, such approaches have proven to be unsuccessful. In order to mitigate these problems, we proposed a new framework for bi-stage contours delineation algorithm based on directional active contours (DAC) incorporating prior knowledge of the prostate shape. We first explicitly addressed the prostate contour delineation problem based on fast globally DAC that incorporates both statistical and parametric shape prior model. In doing so, we were able to exploit the global aspects of contour delineation problem by incorporating a user feedback in contours delineation process where it is shown that only a small amount of user input can sometimes resolve ambiguous scenarios raised by DAC. In addition, once the prostate contours have been delineated, a cost functional is designed to incorporate both user feedback interaction and the parametric shape prior model. Using data from publicly available prostate MR datasets, which includes several challenging clinical datasets, we highlighted the effectiveness and the capability of the proposed algorithm. Besides, the algorithm has been compared with several state-of-the-art methods.

The Association between Metabolic Syndrome, Bone Mineral Density, Hip Bone Geometry and Fracture Risk: The Rotterdam Study

The association between metabolic syndrome (MS) and bone health remains unclear. We aimed to study the association between MS and hip bone geometry (HBG), femoral neck bone mineral density (FN-BMD), and the risk of osteoporosis and incident fractures. Data of 2040 women and 1510 men participants in the third visit (1997–1999) of the Rotterdam Study (RSI-3), a prospective population based cohort, were available (mean follow-up 6.7 years). MS was defined according to the recent harmonized definition. HBG parameters were measured at the third round visit whereas FN-BMD was assessed at the third round and 5 years later. Incident fractures were identified from medical registry data. After correcting for age, body mass index (BMI), lifestyle factors and medication use, individuals with MS had lower bone width (β = -0.054, P = 0.003), lower cortical buckling ratio (β = -0.81, P = 0.003) and lower odds of having osteoporosis (odds ratio =0.56, P = 0.007) in women but not in men. Similarly, MS was associated with higher FN-BMD only in women (β = 0.028, P=0.001). In the analyses of MS components, the glucose component (unrelated to diabetes status) was positively associated with FN-BMD in both genders (β = 0.016, P = 0.01 for women and β = 0.022, P = 0.004 for men). In men, waist circumference was inversely associated with FN-BMD (β = -0.03, P = 0.004). No association was observed with fracture risk in either sex. In conclusion, women with MS had higher FN-BMD independent of BMI. The glucose component of MS was associated with high FN-BMD in both genders, highlighting the need to preserve glycemic control to prevent skeletal complications.

Lean Mass Appears to Be More Strongly Associated with Bone Health than Fat Mass in Urban Black South African Women

OBJECTIVES

To examine the association between body composition (fat mass, lean mass and body mass index, BMI) and bone health (bone mineral density, BMD and fracture risk) in urban black South African women.

DESIGN

A cross sectional study examining associations between body composition, dietary intake (food frequency questionnaire), habitual physical activity (Activity energy expenditure (AEE) measured using an accelerometer with combined heart rate monitor and physical activity questionnaire) and bone health (BMD using dual-energy X ray absorptiometry, DXA and fracture risk).

SETTING

Urban community dwellers from Ikageng in the North-West Province of South Africa.

PARTICIPANTS

One hundred and eighty nine (189) healthy postmenopausal women aged ≥43 years.

RESULTS

Fat mass and lean mass were significantly associated with BMD and fracture risk when adjusted for potential confounders. However, lean mass and not fat mass remained significantly associated with femoral neck BMD (β = 0.49, p <0.001), spine BMD (β = 0.48, p< 0.0001) and hip BMD (β = 0.59, p< 0.0001). Lean mass was also negatively associated with fracture risk (β = -0.19 p =0.04) when both lean and fat mass were in the same model.

CONCLUSION

Lean mass and fat mass were positively associated with femoral neck, spine and hip BMDs and negatively associated with fracture risk in urban black South African women. Our finding suggests that increasing lean mass rather than fat mass is beneficial to bone health. Our study emphasises the importance of positive lifestyle changes, intake of calcium from dairy and adequate weight to maintain and improve bone health of postmenopausal women.

[Radiographic anatomical analysis of the pelvic Teepee view]

OBJECTIVES

To research radiographic anatomy of the main structure of the pelvic Teepee view, including its azimuth direction and view anatomy structure.

METHODS

From June 2013 to June 2014 adult pelvic CT examination results were filtered, excluding skeletal deformities and pelvic osseous destruction caused by tumors, trauma, etc. The data of 2.0 mm contiguous CT scan of 9 adults' intact pelves was,selected and input into Mimics 10.01 involving 7 males and 2 females with an average age of (41.2±10.3) years old. Utilizing the software, the 3D CT reconstructions of the pelves were completed. Setting the transparency being high,the pelvic 3D reconstructions were manipulated from the pelvic anteroposterior view to the combined obturator oblique outlet view and fine-tuned till the regular Teepee-or teardrop-shaped appearance emerges. Cutting tools of the software were at the moment applied to separate the "Teepee" from the main pelvis for each reconstruction. Then the "Teepee" and the rest (main) part of the pelvis were displayed in different color to facilitate the analysis on the Teepee, iliac-oblique, and anteroposterior views.

RESULTS

The "Teepee" started from the posterolateral aspect of the anterior inferior iliac spine and finished at the cortex between the posterior superior iliac spine and the posterior inferior iliac spine in a direction of being from caudal-anterior-lateral to cranial-posterior-medial. The radiographic anatomical composition of the "Teepee" contained one tip, one base,and two aspects. With the inner and outer iliac tables being the inner and outer aspects of the "Teepee", the tip is consequently formed by their intersection. The base is imaged from the cortex of the greater sciatic notch. The medial-inferior-posterior portion of the "Teepee" contains a small part of sacroiliac joint and its corresponding side of bone of the sacrum.

CONCLUSIONS

The "Teepee" is a zone of ample osseous structures of the pelvis, aside from a small medial-inferior-posterior portion, the main zone of which can be accepted as a safe osseous zone for the anchor of implants stabilizing certain pelvic and acetabular fracture patterns. The Teepee view can be utilized as guidance for the safe percutaneous insertion of such implants.

New postcranial material of the early caseid Casea broilii Williston, 1910 (Synapsida: Caseidae) with a review of the evolution of the sacrum in Paleozoic non-mammalian synapsids

Here we use the description of a new specimen of the small caseid synapsid Casea broilii that preserves the sacral, pelvic and hind limb regions in great detail and in three dimensions, as a unique opportunity to reevaluate the early stages in the evolution of the sacrum in the lineage that led to mammals. We place this new material in the context of sacral evolution in early caseid synapsids and conclude that the transition from two to three sacral vertebrae occurred in small-bodied species, suggesting that it was not an adaptation to heavy weight bearing. Furthermore, we compare descriptions of sacral anatomy among known early synapsids, including caseids, ophiacodontids, edaphosaurids, varanopids, and sphenacodontians and review sacral evolution in early synapsids. Based on the descriptions of new species of caseids, edaphosaurids, and varanopids over the past several decades, it is clear that a sacrum consisting of three vertebrae evolved independently at least four times in synapsids during the Late Carboniferous and Early Permian. Furthermore, similarities in the morphologies of the sacral vertebrae and ribs of these early synapsids lead us to conclude that an anterior caudal vertebra had been incorporated into the sacral series convergently in these groups. Given the repeated acquisition of a three-vertebra sacrum in early synapsids and no apparent link to body size, we argue that this sacral anatomy was related to more efficient terrestrial locomotion than to increased weight bearing.

Automated Localization of Multiple Pelvic Bone Structures on MRI

In this paper, we present a fully automated localization method for multiple pelvic bone structures on magnetic resonance images (MRI). Pelvic bone structures are at present identified manually on MRI to locate reference points for measurement and evaluation of pelvic organ prolapse (POP). Given that this is a time-consuming and subjective procedure, there is a need to localize pelvic bone structures automatically. However, bone structures are not easily differentiable from soft tissue on MRI as their pixel intensities tend to be very similar. In this paper, we present a model that combines support vector machines and nonlinear regression capturing global and local information to automatically identify the bounding boxes of bone structures on MRI. The model identifies the location of the pelvic bone structures by establishing the association between their relative locations and using local information such as texture features. Results show that the proposed method is able to locate the bone structures of interest accurately (dice similarity index >0.75) in 87-91% of the images. This research aims to enable accurate, consistent, and fully automated localization of bone structures on MRI to facilitate and improve the diagnosis of health conditions such as female POP.

Does pregnancy and/or shifting positions create more room in a woman's pelvis?

OBJECTIVE

The purpose of this study was to assess the impact of different positions on pelvic diameters by comparing pregnant and nonpregnant women who assumed a dorsal supine and kneeling squat position.

STUDY DESIGN

In this cohort study from a tertiary referral center in Germany, we enrolled 50 pregnant women and 50 nonpregnant women. Pelvic measurements were obtained with obstetric magnetic resonance imaging pelvimetry with the use of a 1.5-T scanner. We compared measurements of the depth (anteroposterior (AP) and width (transverse diameters) of the pelvis between the 2 positions.

RESULTS

The most striking finding was a significant 0.9-1.9 cm increase (7-15%) in the average transverse diameters in the kneeling squat position in both pregnant and nonpregnant groups. The average bispinous diameter in the pregnant group increased from 12.6 cm ± 0.65 cm in the supine dorsal to 14.5 cm ± 0.64 cm (P < .0001) in the kneeling squat; in the nonpregnant group the increase was from 12 cm ± 0.76 cm to 13.9 cm ± 1.04 cm (P < .0001). The average bituberous diameter in the pregnant group increased from 13.6 cm ± 0.93 cm in the supine dorsal to 14.5 cm ± 0.83 cm (P < .0001) in the kneeling squat position; in the nonpregnant women the increase was from 12.6 cm ± 0.92 cm to 13.5 cm ± 0.88 cm (P < .0001).

CONCLUSION

A kneeling squat position significantly increases the bony transverse and anteroposterior dimension in the mid pelvic plane and the pelvic outlet. Because this indicates that pelvic diameters change when women change positions, the potential for facilitation of delivery of the fetal head suggests further research that will compare maternal delivery positions is warranted.