Urinary incontinence in the childbearing woman

Urinary Incontinence (UI) is an often under-reported and untreated medical condition that affects the lives of women of all ages and backgrounds. Although there are six major types of UI, stress urinary incontinence (SUI) is the type most often associated with women of childbearing age. Development of SUI has also been linked to the childbirth process itself. This article will discuss the types, characteristics, and diagnosis of UI, with a focus on SUI. Precipitating factors for SUI, including the influence of pregnancy, childbirth, and aging on its development, will be reviewed.

Point-based rigid-body registration using an unscented Kalman filter

We present and validate a novel registration algorithm mapping two data sets, generated from a rigid object, in the presence of Gaussian noise. The proposed method is based on the Unscented Kalman Filter (UKF) algorithm that is generally employed for analyzing nonlinear systems corrupted by additive Gaussian noise. First, we employ our proposed registration algorithm to fit two randomly generated data sets in the presence of isotropic Gaussian noise, when the corresponding points between the two data sets are assumed to be known. Then, we extend the registration method to the case where the data (with known correspondences) is stimulated by anisotropic Gaussian noise. The new registration method not only reliably converges to the correct registration solution, but it also estimates the variance, as a confidence measure, for each of the estimated registration transformation parameters. Furthermore, we employ the proposed registration algorithm for rigid-body, point-based registration where corresponding points between two registering data sets are unknown. The algorithm is tested on point data sets which are garnered from a pelvic cadaver and a scaphoid bone phantom by means of computed tomography (CT) and tracked free-hand ultrasound imaging. The collected 3-D points in the ultrasound frame are registered to the 3-D meshes in the CT frame by using the proposed and the standard Iterative Closest Points (ICP) registration algorithms. Experimental results demonstrate that our proposed method significantly outperforms the ICP registration algorithm in the presence of additive Gaussian noise. It is also shown that the proposed registration algorithm is more robust than the ICP registration algorithm in terms of outliers in data sets and initial misalignment between the two data sets.

Pubis growth study: Applicability in sexual and age diagnostic

The growth of five variables of the ischiopubic area was analyzed from bone material from birth to old age. The main purpose was to evaluate its significance and capacity for age and sex determination during and after growth. The material used consisted of 327 specimens from four documented Western European collections. Growth curves were calculated by polynomial regression for two classical variables of the ischiopubic area (pubis length and ischiopubic index) and three new variables of the pubic acetabular area (horizontal and vertical diameter of the pubic acetabular area and the pubic acetabular index). None of the curves showed lineal growth, with the exception of the ischiopubic index and the masculine vertical diameter of the pubis acetabular area. Pubis length has the most complicated growth, expressed by a five-degree polynomial. All the variables are useful for adult sex determination, except the pubic acetabular index. The ischopubic index, vertical diameter of the pubic acetabular area and the pubic acetabular index seem to be good variables for sub-adult sex determination. For age estimation the best variables, in both archaeological and forensic remains, are the absolute measurements (pubic length, vertical and horizontal diameter of the pubis). However, pubis length is the best variable for age estimation because it can be applied until 25 years of age.

Hip structural geometry in old and old-old age: similarities and differences between men and women

INTRODUCTION

Changes in hip structure and geometry during aging contribute to decreased bone strength. Little is known, however, about these characteristics at advanced age, when fragility fractures are common. We examined hip structural geometry in men and women of old age (72-84 years) and old-old age (85-96 years) to determine (1) gender differences; (2) whether or not these differences are consistent with the increased occurrence of hip fracture in elderly women, compared to men; and (3) whether or not gender-specific changes are consistent with the increased occurrence of fragility fractures after age 80 in both men and women.

METHODS

We used Hip Structure Analysis (HSA) software to analyze bone densitometry scans from 916 community-dwelling men and women aged 72-96 years. We examined gender differences in hip geometry by age group (72-74, 75-79, 80-84, and >or=85 years) and between gender-specific age groups using multivariable linear regression.

RESULTS

At the femoral narrow neck, there was no gender difference at age 72-74 in bone mineral density (BMD), cortical thickness (CT), and buckling ratio (BR). In contrast, at age 85 or older women had 13% less BMD and CT than men and 8% higher BR. At the intertrochanteric region, women >or=85 years had 25-31% less BMD, cross-sectional bone area (CSA), and CT than men of comparable age, and 38% higher BR. These gender differences were approximately 10-20% greater than those between men and women in their 70s. In gender-specific comparisons, women showed increasing change in structural geometry with increasing age. At both narrow neck and trochanteric regions, women >or=85 years had nearly 35% higher BR, 15% less BMD and CT, and 10% less CSA than women aged 72-74 years. At the narrow neck, they also had 6% greater outer diameter than the youngest women and 8% lower section modulus (Z), an index of bending strength. In contrast, men showed significant age differences only at the narrow neck region, and only at 85 years or older, including 22% higher BR, 10% less BMD and CT, and 5% greater outer diameter, compared to men in their early 70s. Unlike women, men showed no age-associated decline in section modulus.

CONCLUSIONS

Gender differences in hip geometry consistent with increased fragility and fracture risk in elderly women, compared to men, continue into old-old age. Both men and women 85 or older show the most unfavorable features, suggesting a structural basis for the increased occurrence of hip fracture in both sexes at advanced age.

Pelvic skeleton reduction and Pitx1 expression in threespine stickleback populations

The pelvic skeleton of threespine stickleback fish contributes to defence against predatory vertebrates, but rare populations exhibit vestigial pelvic phenotypes. Low ionic strength water and absence of predatory fishes are associated with reduction of the pelvic skeleton, and lack of Pitx1 expression in the pelvic region is evidently the genetic basis for pelvic reduction in several populations. Pelvic vestiges in most populations are larger on the left (left-biased), apparently because Pitx2 is expressed only on that side. We used whole-mount in situ hybridization to study Pitx1 expression in 19 populations of Gasterosteus aculeatus from lakes around Cook Inlet, Alaska, USA. As expected, specimens from six populations with full pelvic structures usually expressed Pitx1 in the limb bud; those from eight populations with left-biased pelvic reduction usually did not express it. Specimens from one of three populations with right-biased or unbiased pelvic reduction sometimes expressed Pitx1. One of two populations in which the pelvic spines (but not the girdle) are usually absent often expressed Pitx1. In terms of Jacob's 1977 'tinkering' metaphor, Pitx1 was the spare part with which natural selection usually tinkered for stickleback pelvic reduction, but it also tinkered with other genes that have smaller effects.

Parallel evolution of Pitx1 underlies pelvic reduction in Scottish threespine stickleback (Gasterosteus aculeatus)

Little is known about the genetic and molecular mechanisms that underlie adaptive phenotypic variation in natural populations or whether similar genetic and molecular mechanisms are utilized when similar adaptive phenotypes arise in independent populations. The threespine stickleback (Gasterosteus aculeatus) is a good model system to investigate these questions because these fish display a large amount of adaptive phenotypic variation, and similar adaptive phenotypes have arisen in multiple, independent stickleback populations. A particularly striking pattern of parallel evolution in sticklebacks is reduction of skeletal armor, which has occurred in numerous freshwater locations around the world. New genetic and genomic tools for the threespine stickleback have made it possible to identify genes that underlie loss of different elements of the skeletal armor. Previous work has shown that regulatory mutations at the Pitx1 locus are likely responsible for loss of the pelvic structures in independent stickleback populations from North America and Iceland. Here we show that the Pitx1 locus is also likely to underlie pelvic reduction in a Scottish population of threespine stickleback, which has apparently evolved pelvic reduction under a different selection regime than the North American populations.

Sexing of human hip bones of Indian origin by discriminant function analysis

The present study was carried out in terms of discriminant analysis and was conducted on 100 human hip bones (of unknown sex) of Indian origin. Based on morphological features, each of the hip bone was rated on a scale of 1-3 for sexing. Twelve measurements and five indices were recorded. The results of discriminant function analysis showed that the acetabular height (vertical diameter) and indices 1 (total pelvic height/acetabular height), 2 (midpubic width/acetabular height) and 3 (pubic length/acetabular height) were very good measures for discriminating sexes. Pelvic brim depth, minimum width of ischiopubic ramus and indices 4 (pelvic brim chord x pelvic brim depth) and 5 (pubic length x 100/ischial length) were also good discriminators of sex. The remaining parameters were not significant as they showed a lot of overlap between male and female categories. The results indicated that one exclusive criterion for sexing was index 3 (pubic length/acetabular height). In comparison with the morphological criteria, the abovementioned index caused 25% and 10.25% increase in the hip bones of female and male category, respectively.

Running in ostriches (Struthio camelus): three-dimensional joint axes alignment and joint kinematics

Although locomotor kinematics in walking and running birds have been examined in studies exploring many biological aspects of bipedalism, these studies have been largely limited to two-dimensional analyses. Incorporating a five-segment, 17 degree-of-freedom (d.f.) kinematic model of the ostrich hind limb developed from anatomical specimens, we quantified the three-dimensional(3-D) joint axis alignment and joint kinematics during running (at ∼3.3 m s–1) in the largest avian biped, the ostrich. Our analysis revealed that the majority of the segment motion during running in the ostrich occurs in flexion/extension. Importantly, however, the alignment of the average flexion/extension helical axes of the knee and ankle are rotated externally to the direction of travel (37° and 21°, respectively) so that pure flexion and extension at the knee will act to adduct and adbuct the tibiotarsus relative to the plane of movement, and pure flexion and extension at the ankle will act to abduct and adduct the tarsometatarsus relative to the plane of movement. This feature of the limb anatomy appears to provide the major lateral (non-sagittal) displacement of the lower limb necessary for steering the swinging limb clear of the stance limb and replaces what would otherwise require greater adduction/abduction and/or internal/external rotation, allowing for less complex joints, musculoskeletal geometry and neuromuscular control. Significant rotation about the joints'non-flexion/extension axes nevertheless occurs over the running stride. In particular, hip abduction and knee internal/external and varus/valgus motion may further facilitate limb clearance during the swing phase, and substantial non-flexion/extension movement at the knee is also observed during stance. Measurement of 3-D segment and joint motion in birds will be aided by the use of functionally determined axes of rotation rather than assumed axes, proving important when interpreting the biomechanics and motor control of avian bipedalism.

Impact of variations in bony pelvic dimensions on performing radical retropubic prostatectomy

OBJECTIVES

To investigate the impact of variations in bony pelvic dimensions observed from preoperative magnetic resonance imaging on operative time, intraoperative blood loss, and surgical margin status on performing open radical retropubic prostatectomy.

METHODS

A prospective study was undertaken in which preoperative magnetic resonance imaging was performed in 190 patients who were diagnosed with clinically localized prostate cancer before radical retropubic prostatectomy. Using the magnetic resonance image findings, various bony pelvic dimensions were measured. The associations of the measured pelvic dimensions and various clinicopathologic factors with the operative time, estimated blood loss, and surgical margin status were analyzed on multivariate analyses.

RESULTS

For operative time, none of the individual pelvic dimensions measured demonstrated significant associations on univariate analysis. In contrast, only the newly developed parameter, the pelvic dimension index, approached significance (P = 0.095). Only body mass index (BMI) proved to be independently associated with the operative time on multivariate analysis (P = 0.030). Also, only the prostate volume (P = 0.015) was independently associated with the estimated blood loss. For the surgical margin status, the preoperative PSA level (P = 0.041), pathologic Gleason score (P = 0.015), and BMI (P = 0.020), along with the pelvic dimension index (P = 0.048), demonstrated significant associations on univariate analyses. However, only the PSA level (P = 0.071) and BMI (P = 0.059) approached significance on multivariate analysis.

CONCLUSIONS

Our results have demonstrated that variations in the bony pelvic dimensions might have some impact, but not significantly so, on open radical retropubic prostatectomy compared with other patient-related baseline factors such as the BMI or prostate volume.

Sex differences in clinical measures of lower extremity alignment

STUDY DESIGN

Descriptive, cohort design.

OBJECTIVES

To comprehensively examine sex differences in clinical measures of static lower extremity alignment (LEA).

BACKGROUND

Sex differences in LEA have been included among a myriad of risk factors as a potential cause for the increased prevalence of knee injury in females. While clinical observations suggest that sex differences in LEA exist, little empirical data are available to support these sex differences or the normal values that should be expected in a healthy population.

METHODS AND MEASURES

The right and left static LEA of 100 healthy college-age participants (50 males [mean +/- SD age, 23.3 +/- 3.6 years; height, 177.8 +/- 8.0 cm, body mass, 80.4 +/- 11.6 kg] and 50 females [mean +/- SD age, 21.8 +/- 2.5 years; height, 164.3 +/- 6.9 cm; body mass, 67.4 +/- 15.2 kg]) was measured. Each alignment characteristic was analyzed via separate repeated-measures analyses of variance, with 1 between-subject factor (sex) and 1 within-subject factor (side).

RESULTS

There were no significant sex-by-side interactions and no differences between sides. Females had greater mean anterior pelvic tilt, hip anteversion, quadriceps angles, tibiofemoral angles, and genu recurvatum than males (P < .0001). No sex differences were observed in tibial torsion (P = .131), navicular drop (P = .130), and rearfoot angle (P = .590).

CONCLUSION

Sex differences in LEA indicate that females, on average, have greater anterior pelvic tilt, thigh internal rotation, knee valgus, and genu recurvatum. These sex differences were not accompanied by differences in the lower leg, ankle, and foot. Understanding these collective sex differences in LEA may help us to better examine the influence of LEA on dynamic lower extremity function and clarify their role as a potential injury risk factor.

Directional asymmetry of pelvic vestiges in threespine stickleback

Extensive reduction of the size and complexity of the pelvic skeleton (i.e., pelvic reduction) has evolved repeatedly in Gasterosteus aculeatus. Asymmetrical pelvic vestiges tend to be larger on the left side (i.e., left biased) in populations studied previously. Loss of Pitx1 expression is associated with pelvic reduction in G. aculeatus, and pelvic reduction maps to the Pitx1 locus. Pitx1 knockouts in mice have reduced hind limbs, but the left limb is larger. Thus left-biased directional asymmetry of stickleback pelvic vestiges may indicate the involvement of Pitx1 in pelvic reduction. We examined 6,356 specimens from 27 Cook Inlet populations of G. aculeatus with extensive pelvic reduction. Samples from 20 populations exhibit the left bias in asymmetrical pelvic vestiges expected if Pitx1 is involved, and three have a slight, non-significant left bias. However, samples from three populations have a significant right bias, and one large sample from another population has equal frequencies of specimens with larger vestiges on the left or right side. A sample of fossil threespine stickleback also has significantly left-biased pelvic vestiges. These results suggest that silencing of Pitx1 or the developmental pathway in which it functions in the pelvis is the usual cause of pelvic reduction in most Cook Inlet populations of G. aculeatu, and that it caused pelvic reduction at least 10 million years ago in a stickleback population. A different developmental genetic mechanism is implicated for three populations with right-biased pelvic vestiges and for the population without directional asymmetry.

Costal process of the first sacral vertebra: Sexual dimorphism and obstetrical adaptation

The human sacrum is sexually dimorphic, with males being larger than females in most dimensions. Previous studies, though, suggest that females may have a longer costal process of the first sacral vertebra (S1) than males. However, these studies neither quantified nor tested statistically the costal process of S1. This study compares S1 with the five lumbar vertebrae (L1 to L5) for a number of metric dimensions, including costal process length. Four issues are addressed, the: 1) hypothesis that females have a longer costal process of S1 than males; 2)hypothesis that homologous structures (i.e., costal processes of L1 to S1) differ in their direction of sexual dimorphism; 3) importance of the costal process of S1 to the obstetrical capacity of the pelvis; and 4) evolution of sexual dimorphism in costal process length of S1. One hundred ninety-seven individuals, including males and females of American blacks and whites, from the Hamann-Todd and Terry Collections were studied. Results show that males are significantly larger than females for most vertebral measurements, except that females have a significantly longer costal process of S1 than males. Costal process length of S1 is positively correlated with the transverse diameter and circumference of the pelvic inlet. The magnitude of sexual dimorphism in costal process length of S1 ranks this measure among the most highly dimorphic of the pelvis. Compared with the humans in this study, australopithecines have a relatively long costal process of S1, but their broad sacrum was not associated with obstetrical imperatives.

Age-related trends in hip geometry in Sri Lankan women: a cross-sectional study

Indices of hip geometry are known to be predictive of hip fractures while sex and ethnic differences in hip geometry have been previously demonstrated. Age-related trends in hip geometry among Asians, however, have not been studied sufficiently. A total of 280 healthy, perimenopausal women, aged between 32 and 97 years, were selected from the Community Study Area of the Faculty of Medicine, Galle, Sri Lanka. Hip DXA images were analyzed further to calculate the hip axis length, neck-shaft angle, and femoral neck width at the narrowest point of the femoral neck. Standard formulae were used to calculate cross-sectional area, cross-sectional moment of inertia, and section modulus in the femoral neck region. Mean (SD) age, weight, height, femoral neck bone mineral density (BMD), hip axis length, neck-shaft angle, neck width, cross-sectional area, and cross-sectional moment of inertia of the study sample were 56.8 (13.0) years, 47.8 (10.1) kg, 1.48 (0.06) m, 0.704 (0.147) g/cm(2), 90.6 (5.6) mm, 123.2 (5.7) degrees, 2.99 (0.24) cm, 2.00 (0.42) cm(2), and 1.62 (0.47) cm(4), respectively. Height and weight of subjects had positive correlations with most of the indices of hip geometry. Femoral neck BMD, cross-sectional area and section modulus showed a rapid reduction during the postmenopausal period. With advancing age, there was a marginal but statistically nonsignificant expansion of the neck width, increase in the hip axis length, and narrowing of the neck-shaft angle. In conclusion, this study demonstrated a gradual loss of BMD in postmenopausal age, accompanied by thinning of the cortical shell and deterioration of the resistance to bending in the femoral neck of this group of healthy women. The clinical relevance of the marginal changes seen in other indices such as neck-shaft angle, hip axis length, and neck width is not known.

The use of sparse CT datasets for auto-generating accurate FE models of the femur and pelvis

The finite element (FE) method when coupled with computed tomography (CT) is a powerful tool in orthopaedic biomechanics. However, substantial data is required for patient-specific modelling. Here we present a new method for generating a FE model with a minimum amount of patient data. Our method uses high order cubic Hermite basis functions for mesh generation and least-square fits the mesh to the dataset. We have tested our method on seven patient data sets obtained from CT assisted osteodensitometry of the proximal femur. Using only 12 CT slices we generated smooth and accurate meshes of the proximal femur with a geometric root mean square (RMS) error of less than 1 mm and peak errors less than 8 mm. To model the complex geometry of the pelvis we developed a hybrid method which supplements sparse patient data with data from the visible human data set. We tested this method on three patient data sets, generating FE meshes of the pelvis using only 10 CT slices with an overall RMS error less than 3 mm. Although we have peak errors about 12 mm in these meshes, they occur relatively far from the region of interest (the acetabulum) and will have minimal effects on the performance of the model. Considering that linear meshes usually require about 70-100 pelvic CT slices (in axial mode) to generate FE models, our method has brought a significant data reduction to the automatic mesh generation step. The method, that is fully automated except for a semi-automatic bone/tissue boundary extraction part, will bring the benefits of FE methods to the clinical environment with much reduced radiation risks and data requirement.

Bone density and bone area in Canadian Aboriginal women: the First Nations Bone Health Study

INTRODUCTION

Canadian Aboriginal women are at increased risk of fracture compared with the general population.

HYPOTHESIS

There is disproportionately reduced bone density in Aboriginal women as compared to white females of similar age.

METHODS

A random age-stratified (25-39, 40-59 and 60-75) sample of Aboriginal women (n=258) and white women (n=181) was recruited. All subjects had calcaneus and distal forearm bone density measurements, and urban participants (n=397 [90.4%]) also had measurements of the lumbar spine, hip and total body.

RESULTS

Unadjusted measurements were similar in the two groups apart from the distal forearm which showed a significantly lower mean Z-score in the Aboriginal women (p=0.03). Aboriginal women were heavier than white women (81.0+/-18.0 kg vs. 76.0+/-18.0 kg, p=0.02). Weight was directly associated with BMD at all measurement sites (p<0.00001) and potentially confounded the assessment of ethnicity on bone mass measurements. Weight-adjusted ANCOVA models demonstrated significantly lower bone density in Aboriginal than white women for the calcaneus, distal forearm, and total body (all p<0.05), but not at the other sites. ANCOVA models (adjusted for age, height and weight) were used to explore differences in bone area and bone mineral content (BMC). There was a significant effect of ethnicity on bone area with Aboriginal women having larger adjusted mean values than white women (lumbar spine p=0.038, total hip p=0.0004, total body p=0.020). In contrast, there was no detectable effect of ethnicity on BMC (all p>0.2).

CONCLUSIONS

We identified significant site-specific differences in age-and weight-adjusted bone density for Aboriginal and white women. Larger bone area, rather than a reduction in BMC, appeared to be primarily responsible. Further work is needed to define how these differences in bone density and geometry affect indices of bone strength.

Relationship between thoracic, lordotic, and pelvic inclination and craniofacial morphology in adults

OBJECTIVE

To analyze the correlation ratios between the spinal posture (thoracic, lordotic, and pelvic inclination) and the craniofacial morphology.

MATERIALS AND METHODS

The sample consisted of 53 healthy adults (32 women, 21 men; mean age 24.6 years). Six angular skeletal measurements (facial axis, mandibular plane angle, inner gonial angle, lower facial height, facial depth, and maxilla position) were determined based on the analysis of lateral head cephalographs. Rasterstereography was used for a precise reconstruction of the back sagittal profile. From the profile parameters, the upper thoracic inclination, the thoracic angle, the lordotic angle, and the pelvic inclination were determined. The correlations to the craniofacial morphology were calculated by means of the Pearson and Mann-Whitney U-test.

RESULTS

Significant correlations could be obtained with respect to the facial axis and the lordotic angle, the facial axis and the pelvic inclination, the inner gonial angle and the lordotic angle, the inner gonial angle and the pelvic inclination, the mandibular plane angle and the lordotic angle, the mandibular plane angle and the pelvic inclination, as well as the facial depth and the pelvic inclination.

CONCLUSIONS

In the case of postural disorders of the back shape, an interdisciplinary treatment approach seems to be of clinical value. Further prospective studies are necessary to prove how changes in craniofacial parameters can affect the postural balance of an individual.

A genomewide scan for quantitative trait loci underlying areal bone size variation in 451 Caucasian families

BACKGROUND

Bone size is an important determinant of bone strength and is under strong genetic control.

OBJECTIVE

To identify quantitative trait loci (QTL) for areal bone size variation, a large-scale genomewide linkage scan was carried out in 451 Caucasian families.

PARTICIPANTS AND METHODS

Of 4124 people with phenotypes, 3899 were genotyped with 410 microsatellite markers. Multipoint linkage analyses were carried out in the entire sample, as well as in men and women separately. Potential epistatic interactions between identified genomic regions were also assessed.

RESULTS

Several potentially important genomic regions were identified, such as 8q24 for hip bone size (logarithm of the ratio of the odds that two loci are linked (LOD) 3.27) and 2p24 (LOD 2.04) for spine bone size. 8q24 may also interact with 19p13 to affect hip bone size. Several sex-specific QTL were also detected, such as 14q21 (LOD 2.94) for wrist bone size in women and 16q12 (LOD 2.19) for hip bone size in men.

CONCLUSIONS

Together with previous findings, this study has further delineated the genetic basis of bone size and laid a foundation for future studies to eventually elucidate the mechanisms of bone size regulation and associated fracture risks.

[Method selection from medical imaging examinations in evaluation of pelvic injury in forensic medicine]

OBJECTIVE

To table a proposal for select using the medical imaging methods to evaluate pelvic injury in forensic field, by studying the structure of pelvis and radiological methods in common use.

METHODS

A study of several cases of pelvic injury was done, in which biomechanics and classification of pelvic injury were analyzed, moreover imaging methods were compared with each other, such as fluoroscopy, X-ray photography, computerized tomography (CT) and so on.

RESULTS

Four cases of pelvic injury are all multiple injuries, confirmed by X-ray photography and CT examination approvingly.

CONCLUSIONS

Authors advocate that pelvic injury mechanism and biomechanics should be considered accordingly, multiple injuries should be attracted notice, so as to select suitable imaging methods to evaluate pelvic injury exactly.

Interexaminer reliability of three methods of combining test results to determine side of sacral restriction, sacral base position, and innominate bone position

CONTEXT

Sacroiliac joint dysfunction is diagnosed based on the combined results of several palpatory examinations. Previous studies have compared the interexaminer reliability of only one of these methods of diagnosis.

OBJECTIVE

To compare the interexaminer reliability of three methods of combining palpatory examinations to determine the side of sacroiliac joint dysfunction, sacral base position, and innominate bone position.

DESIGN

Blinded single-cohort reliability study.

METHODS

Patients with low back pain underwent two identical sets of palpatory examinations given by two physicians, separately, at a university spine center. The results of each set were compiled and interpreted by three methods: using the test result with the highest interexaminer reliability (method 1), requiring at least one test result to be abnormal for the variable to be abnormal (method 2), and requiring all test results to be abnormal for the variable to be abnormal (method 3). The kappa was calculated for each method.

RESULTS

There were 24 subjects (mean age, 68.3 years), of which 15 (62%) were women. The kappa was consistently higher with method 1, at 0.47, 0.08, and 0.32 for the sacral position, innominate bone position, and side of sacroiliac joint dysfunction, respectively. Corresponding values for method 2 were 0.09, 0.4, and 0.16, and for method 3 were 0.16, 0.1, and -0.33.

CONCLUSION

Using the results of the most reliable examination consistently has the best interexaminer reliability.

Correlations of Total Pelvic Spongiosa Volume With Both Anthropometric Parameters and Computed Tomography–Based Skeletal Size Measurements

Patient-specific dosimetry within the field of molecular radiotherapy continues to pose a challenge owing to the difficulty in predicting marrow toxicity. This study examined the correlation between total pelvic spongiosa volume (TPSV) and independent variables, which include both readily measured or calculated anthropometric parameters (AP), and image-based skeletal measurements requiring computed tomography (CT) images or skeletal radiographs. Fourteen (14) patients (5 male and 9 female) undergoing total hip arthroplasty (THA) were subjected to modified pelvic CT scans. These scans were utilized to estimate TPSV, which was comprised of the volumes of spongiosa within the L5 vertebra, os coxae, sacrum, and both proximal femurs. The APs investigated included total body height (TBH), total body mass (TBM), body mass index (BMI), body surface area (BSA), maximum effective mass (MEM), lean body mass (LBM), and fat-free mass (FFM). Skeletal measurements were also obtained from the CT images of the pelvic region. Correlation coefficients (r) were obtained for TPSV and each set of APs as well as each set of skeletal measurements. Total body height (r = 0. 80) and os coxae height (r = 0.83) had the highest correlation coefficients of all the APS and skeletal measurements, respectively. FFM (r = 0.50), LBM (r = 0.42), TBM (r = 0.11), and BSA (r = 0.11) did not correlate well with TPSV, which accounts for approximately 45% of total spongiosa seen throughout the skeleton at sites associated with active bone marrow. Skeletal height measurements appear to have a much higher correlation with TPSV than either their corresponding skeletal width measurements or parameters that are a function of an individual's TBM.

In Vitro Study of the Ilial Anatomic Landmarks for Safe Implant Insertion in the First Sacral Vertebra of the Intact Canine Sacroiliac Joint

OBJECTIVE

To define landmarks on the canine ilial wing for accurate, consistent insertion of implants into the 1st sacral (S1) vertebral body when the sacroiliac joint is intact.

STUDY DESIGN

Anatomic study.

ANIMALS

Intact, cadaveric canine pelves and sacra (n=25).

METHODS

Median sections (5 specimens) were drilled from the center of S1 in a lateral direction, exiting on the ilial wing. Landmarks on the ilial wing and shaft used to define this exit point were then used to locate this point on both wings of 20 articulated specimens, positioned and rigidly held so that the dorsal plane of the pelvis was aligned with a plumb line and the median plane of the pelvis was horizontal. A 2 mm hole was drilled from the marked point, parallel to the plumb line, until it exited the contralateral ilial wing. Distance of drill hole position from the geometric center (GC) of S1 was located on median and paramedian plane images derived from plane, computed tomographic (CT) scans.

RESULTS

The entire drill hole was located within S1 in 18 specimens. Mean deviation of the hole from GC (ratio of the distance of GC from the closest S1 body border) in median section was 0.40 +/- 0.29 (craniocaudal direction) and 0.29 +/- 0.23 (dorsoventral).

CONCLUSIONS

Use of ilial wing landmarks and drilling perpendicular to the median plane will improve accuracy for insertion of implants into S1 when the sacroiliac joint is intact.

CLINICAL RELEVANCE

Ilial wing landmarks should be used to improve accuracy of implant insertion into S1.

Postcranial skeleton of Shinisaurus crocodilurus (Squamata: Anguimorpha)

The postcranial skeleton is poorly known for Shinisaurus crocodilurus, the Chinese crocodile lizard. Discrepancies exist between published accounts of Shinisaurus; moreover, comparisons with complete specimens show important differences from the published descriptions. Contrary to some publications, the axial skeleton variably consists of 26 or 27 presacral vertebrae, including eight cervical vertebrae. Humeral entepicondylar and ectepicondylar foramina are present, as are an epipubis and hypoischium, and the post-tubercular portion of the pubis is subequal in length to the proximal portion. Sesamoids are present in the knee, elbow, and between the penultimate phalanges and unguals. A cartilaginous strut joins the clavicles and interclavicle. Comparative investigation of extant anguimorphs add context to these observations and support the conclusion that Mosasauroidea possessed eight or more (rather than seven) cervical vertebrae. Overall, the postcranium of Shinisaurus is relatively unspecialized for Anguimorpha, although it may be diagnosed accurately by a combination of character states.

Traumatic Pelvic Fractures

Pelvic fractures can be a big challenge in caring for the injured patient. Pelvic fractures are important as a cause for morbitidy and mortality. The mortality can be 30% with unstable pelvic ring injuries, and 10-12% of this percentage alone is due to blood loss. Multiple complications can occur during a pelvic fracture. This article will help nurses assess and manage patients with pelvic injuries. Topics covered in the article include basic anatomy of the pelvis, diagnostic tests performed after a pelvic fracture, types of pelvic fractures, management of pelvic fractures, and complications.