Early clinical and radiological improvement in a young boy with metaphyseal anadysplasia type 2.

Metaphyseal anadysplasia is a very rare hereditary skeletal dysplasia with onset occurring normally during the second and third years of life, but unlike many other dysplasias, symptoms appear to resolve by adolescence. Two types exist, the more severe form, type 1, with both autosomal dominant and recessive inheritance due to pathogenic variants in MMP13, whilst type 2, an even rarer form is due to biallelic MMP9 variants. To date, only two metaphyseal anadysplasia type 2 families have been reported. We describe a third family, a young boy, born to consanguineous parents, referred at 19 months old for abnormal gait due to bowed legs. Clinical and radiological examination revealed scoliosis, genu varum and metaphyseal abnormalities. A homozygous MMP9 nonsense variant, NM_004994.2:c.1764G>A; p.(Trp588*) was identified. By the age of 39 months, lower limb alignment and metaphyseal features had already significantly improved and scoliosis had disappeared. This case confirms that biallelic MMP9 variants cause this very rare skeletal dysplasia, metaphyseal anadysplasia type 2 but also shows that the skeletal manifestations can improve within a short period time and at an early age.

Limb development in skeletally-immature large-sized dogs: A radiographic study.

Despite the extreme morphological variability of the canine species, data on limb development are limited and the time windows for the appearance of the limb ossification centres (OCs) reported in veterinary textbooks, considered universally valid for all dogs, are based on dated studies. The aim of this study was to acquire up-to-date information regarding the arm, forearm and leg bone development in skeletally-immature large-sized dogs from 6 weeks to 16 weeks of age. Nine litters of 5 large-sized breeds (Boxer, German Shepherd, Labrador Retriever, Saarloos Wolfdog, White Swiss Shepherd Dog) were included, for a total of 54 dogs, which were subject to radiographic examination on a bi-weekly basis. The appearance of 18 limb OCs was recorded and 14 radiographic measurements were performed; their relationship with age and body weight was investigated and any breed differences were analysed using different statistical non-parametric tests. The number of OCs present was significantly different at 6 and 8 weeks of age between the investigated breeds. The appearance of the OCs occurred earlier in the Saarloos Wolfdog, while the Labrador Retriever was the later breed. In Boxers and Labrador Retrievers, various OCs showed a delayed appearance compared to the data reported in the literature. The number of OCs was strongly and positively correlated to body weight. Breed differences were also observed in the relative increase of the measured OCs and were not limited to dogs of different morphotypes. Statistically significant differences were most frequently observed between Saarloos Wolfdogs and the other breeds. The OCs that showed a greater variability in their development were the olecranon tuber, the patella and the tibial tuberosity. Their increase was more strongly correlated with the dog's age and body weight. Our data strongly suggest that differences in limb development exist in dog breeds of similar size and morphotype.

Estimation of stature from radiographically determined lower limb bone length in modern Chinese.

To develop population - specific stature prediction equations from measurements of the lower limb bone in a contemporary Chinese. 303 individuals of Han group in Western China, including 201 females and 102 males were collected. The study sample was randomly divided into two subgroups. A calibration sample, which consisted of 171 females and 87 males, was used to develop the regression formula. A validation sample comprising the remaining 30 female and 15 male individuals was then used to test the predictive accuracy of the established formula. The regression equations were developed from intact bones and fragments of the femur, tibia and fibula, the maximum lengths of femur, tibia, and fibula were highly correlated with the stature. The maximum length of femur provide the most accurate result with the prediction accuracy of 3.84 cm for unknown sex, 4.00 cm in the male group, 3.45 cm in the female group, 3.61 cm in the group with age no more than 45, 3.45 cm in the group with age above 45. Moreover, the multiple regression equations were developed, and they portray a more accurate stature in instances in which the femur, tibia and fibula are available. This paper provides indications that the femur, tibia and fibula are important bones for stature estimation and they could be effectively used in forensic cases.

Standardizing ordinal subadult age indicators: Testing for observer agreement and consistency across modalities.

Skeletal and dental data for subadult analyses obtained from dry bones or various types of medical images, such as computed tomography (CT) scans or conventional radiographs/x-rays, should be consistent and repeatable to ensure method applicability across modalities and support combining study samples. The present study evaluates observer agreement of epiphyseal fusion and dental development stages obtained on CT scans of a U.S. sample and the consistency of epiphyseal fusion stages between CT scans and projected scan radiographs/scout images (U.S. CT sample), and between dry bones and conventional x-rays (Colombian osteological sample). Results show that both intra- and interobserver agreements of scores on CT scans were high (intra: mean Cohen's kappa=0.757-0.939, inter: mean Cohen's kappa=0.773-0.836). Agreements were lower for dental data (intra: mean Cohen's kappa=0.757, inter: mean Cohen's kappa=0.773-0.0.820) compared to epiphyseal fusion data (intra: mean Cohen's kappa=0.939, inter: mean Cohen's kappa=0.807-0.836). Consistency of epiphyseal fusion stages was higher between dry bones and conventional x-rays than between CT scans and scout images (mean Cohen's kappa=0.708-0.824 and 0.726-0.738, respectively). Differences rarely surpassed a one-stage value between observers or modalities. The complexity of some ossification patterns and superimposition had a greater negative impact on agreement and consistency rates than observer experience. Results suggest ordinal subadult skeletal data can be collected and combined across modalities.

Protein-Degrading Enzymes in Osteoarthritis.

OBJECTIVE: TGFß1 plays an important role in the metabolism of articular cartilage and bone; however, the pathological mechanism and targets of TGFß1 in cartilage degradation and uncoupling of subchondral bone remodeling remain unclear. Therefore, in this study, we investigated the relationship between TGFß1 and major protein-degrading enzymes, and evaluated the role of high levels of active TGFß1 in the thickening of subchondral bone and calcification of articular cartilage. MATERIALS AND METHODS: The expression of TGFß1 and protein-degrading enzymes in clinical samples of articular cartilage and subchondral bone obtained from the knee joint of patients with osteoarthritis was detected by immunohistochemistry. The expression levels of TGFß1, MMP-3, MMP-13 and IL-1ß in cartilage and subchondral bone tissues were detected by absolute real-time quantitative RT-PCR. The expression of TGFß1, nestin and osterix in subchondral bone was detected by Western blot analysis and immunohistochemistry. The degree of subchondral bone thickening was determined by micro-computed tomography (CT) imaging. RESULTS: Expression of TGFß1 and cartilage-degrading enzymes was higher in the cartilage-disrupted group than that in the intact group. Furthermore, expression of TGFß1, nestin and osterix was significantly higher in the OA group than that in the control group. Micro-CT imaging showed that in the OA group, the subchondral bone plate is thickened and the density is increased. The trabecular bone structure is thick plate-like structure, the thickness of the trabecular bone is increased and the gap is small. CONCLUSIONS: The data suggest that highly active TGFß1 activates the expression of cartilage-degrading enzymes. Abnormally activated TGFß1 may induce formation of the subchondral bone and expansion of the calcified cartilage area, eventually leading to degradation of the cartilage tissue.

Basic morphometry, microcomputed tomography and mechanical evaluation of the tibiotarsal bone of a dual-purpose and a broiler chicken line.

Continuous loading of the skeleton by the body's weight is an important factor in establishing and maintaining bone morphology, architecture and strength. However, in fast-growing chickens the appendicular skeleton growth is suboptimal making these chickens predisposed to skeletal mineralization disorders and fractures. This study compared the macro- and microstructure as well as the mechanical properties of the tibiotarsus of a novel dual-purpose, Lohmann Dual (LD) and a highly developed broiler, Ross (Ross 308) chicken line. Eighty one-day-old male chicks of each line were grown until their body weight (BW) reached 2000g. Starting at the day of hatching, six birds of each line were sampled weekly. The weight, length and width of the tibiotarsus were measured and its mechanical properties (rigidity, M-Max and the M-fracture) were evaluated using the three-point bending test. Additionally, the mineral density of both, trabecular and cortical bone, the bone volume fraction, the trabecular number, thickness and separation plus cortical thickness of both chicken lines were analyzed using microcomputed tomography. The growth of the tibiotarsus in both chicken lines followed a similar pattern. At the same age, the lighter LD chickens had shorter, thinner and lighter tibiotarsi than those of Ross chickens. However, the LD chickens had a similar cortical thickness, bone volume fraction and similar mineral density of both trabecular and cortical bone to that of Ross chickens. Furthermore, the tibiotarsus of LD chickens was longer, heavier and wider than those of Ross chickens of the same BW. In addition the rigidity of the LD tibiotarsus was greater than that of Ross chickens. This suggests that the tibiotarsus of LD chickens had more bending resistance than those of Ross chickens of the same BW. Consequently, fattening LD chickens to the marketable weight should not affect their leg skeleton stability.

Two-dimensional/three-dimensional EOS™ imaging is reliable and comparable to traditional X-ray imaging assessment of knee osteoarthritis aiding surgical management.

BACKGROUND: X-ray imaging is the gold standard for assessing lower limb conditions and preoperative planning. A novel low-radiation-dose EOS™ imaging system enables full-length weight-bearing imaging in one session and three-dimensional (3D) reconstruction. Thus, it can improve assessment of limb deformities, preoperative planning and follow-up with lower radiation exposure. The objective of this study was to measure lower limbs from EOS™ images to determine its accuracy and reproducibility in comparison with long-leg X-ray images. METHODS: Over a one-year period, twenty patients (forty lower limbs) with knee osteoarthritis were recruited from clinic. Thirty-five (five excluded due to knee prosthesis) two-dimensional- (2D) EOS™, 3D EOS™ and X-ray images were measured independently by four observers, measuring lower limb angles and lengths. On average, twelve weeks later, observers repeated measurements on 2D EOS™ and X-ray images. RESULTS: A t-test comparing 2D EOS™ with X-ray images showed no significant difference in all angle and length measurements (P > 0.05). When analysing observers separately, all measurements showed no significant difference, apart from the femoral anatomic-mechanical angle (fAMA) from observer 2 (2D EOS™ fAMA 6.21° vs. X-ray fAMA 7.10°, P = 0.02). Intra-observer intraclass correlation coefficient (ICC) for 2D EOS™ and X-ray was 1.00 and 1.00, respectively, and inter-observer ICC was 1.00 and 0.99, respectively. A t-test comparing 2D- with 3D EOS™ images showed no significant difference in all measurements. A t-test comparing 3D EOS™ with X-ray images showed no significant difference in all measurements. CONCLUSION: This study showed the EOS™ imaging system to be a valid alternative method of imaging lower limbs for alignment, measurements and preoperative arthroplasty planning.

Three-dimensional assessment of lower limb alignment: Reference values and sex-related differences.

BACKGROUND: Three-dimensional (3D) preoperative planning and assisted surgery is increasingly popular in deformity surgery and arthroplasty. Reference ranges for 3D lower limb alignment are needed as a prerequisite for standardized analysis of alignment and preoperative planning in 3D, but are not yet established. METHODS: On 60 3D bone models of the lower limbs based on computed tomography data, fifteen parameters per leg were assessed by standardized validated 3D analysis. Distribution parameters and differences between sexes were evaluated. Reference values were generated by adding/subtracting one standard deviation from the mean. RESULTS: Women had a significantly lower mean mechanical lateral distal femoral angle compared with men (86.4 ±â€¯2.1° vs. 87.8 ±â€¯2.0°; P < .05) and significantly lower mean joint line convergence angle (-2.5 ±â€¯1.4° vs. -1.3 ±â€¯1.2; P < .01), but higher mean hip knee ankle angle (178.9 ±â€¯1.9° vs. 177.8 ±â€¯2.3°; P < .05) and mean femoral torsion (18.2 ±â€¯9.5° vs. 13.2 ±â€¯6.4°; P < .05), resulting in a tendency towards valgus alignment and vice versa for men. Differences in mean medial proximal tibial angle were not significant. The mean mechanical axis deviation from the tibial knee joint center was 6.9 ±â€¯7.3 mm medial and 1.4 ±â€¯16.1 mm ventral without significant differences between sexes. CONCLUSIONS: We describe total and sex-related reference ranges for all alignment relevant axes and joint angles of the lower limb. There are sex-related differences in certain alignment parameters, which should be considered in analysis and surgical planning.

Scanner influence on the mechanical response of QCT-based finite element analysis of long bones.

Patient-specific QCT-based finite element (QCTFE) analyses enable highly accurate quantification of bone strength. We evaluated CT scanner influence on QCTFE models of long bones. A femur, humerus, and proximal femur without the head were scanned with K2HPO4 phantoms by seven CT scanners (four models) using typical clinical protocols. QCTFE models were constructed. The geometrical dimensions, as well as the QCT-values expressed in Hounsfield unit (HU) distribution was compared. Principal strains at representative regions of interest (ROIs), and maximum principal strains (associated with fracture risk) were compared. Intraclass correlation coefficients (ICCs) were calculated to evaluate strain prediction reliability for different scanners. Repeatability was examined by scanning the femur twice and comparing resulting QCTFE models. Maximum difference in geometry was 2.3%. HU histograms before phantom calibration showed wide variation between QCT scans; however, bone density histogram variability was reduced after calibration and algorithmic manipulation. Relative standard deviation (RSD) in principal strains at ROIs was <10.7%. ICC estimates between scanners were >0.9. Fracture-associated strain had 6.7%, 8.1%, and 13.3% maximum RSD for the femur, humerus, and proximal femur, respectively. The difference in maximum strain location was <2 mm. The average difference with repeat scans was 2.7%. Quantification of strain differences showed mean RSD bounded by ∼6% in ROIs. Fracture-associated strains in "regular" bones showed a mean RSD bounded by ∼8%. Strains were obtained within a ±10% difference relative to the mean; thus, in a longitudinal study only changes larger than 20% in the principal strains may be significant. ICCs indicated high reliability of QCTFE models derived from different scanners.

Comparison of Cone-Beam Computed Tomography and Multislice Computed Tomography in the Assessment of Extremity Fractures.

OBJECTIVES: The aims of this study were to evaluate the agreement between cone-beam computed tomography (CBCT) and multislice computed tomography for the characterization of extremity fractures and to compare image quality, radiation dose, and patient tolerance. METHODS: Thirty-six patients with suspected fracture affecting distal extremities or who required preoperative fracture assessment were enrolled prospectively. Each patient underwent CBCT and multislice computed tomography the same day. Both examinations were evaluated independently twice by 2 trained radiologists using the Müller AO classification for fracture characterization. RESULTS: Cohen κ coefficient for agreement between the imaging techniques was almost perfect for fracture characterization, κ = 0.94 [95% confidence interval, 0.91-0.98]. There was substantial to almost perfect agreement for secondary findings. Cone-beam computed tomography was well tolerated and significantly less irradiant and had better subjective image. CONCLUSIONS: An excellent agreement between both imaging techniques was found. This confirms the ability of CBCT to assess fractures and its potential in the management of patients with distal limb trauma.

The effectiveness of ultrasound in the detection of fractures in adults with suspected upper or lower limb injury: a systematic review and subgroup meta-analysis.

BACKGROUND: The aim of the present review is to assess the effectiveness of ultrasound (US) in the detection of upper and lower limb bone fractures in adults compared to a diagnostic gold standard available in secondary and tertiary care centres (e.g. radiography, CT scan or MRI). METHODS: The review followed PRISMA guidelines and used a database-specific search strategy with Medline, EMBASE and The Cochrane Library plus secondary sources (see supplementary material for completed PRISMA checklist). Diagnostic performance of ultrasound was assessed with a qualitative synthesis and a meta-analysis of two data subgroups. RESULTS: Twenty-six studies were included (n = 2360; fracture prevalence =5.3 % to 75.0%); data were organised into anatomical subgroups, two of which were subjected to meta-analysis. Sensitivity and specificity ranged from 42.11 - 100% and 65.0 - 100%, with the highest diagnostic accuracy in fractures of the foot and ankle. The pooled sensitivity and specificity of US was 0.93 and 0.92 for upper limb fractures (I2 = 54.7 % ; 66.3%), and 0.83 and 0.93 for lower limb fractures (I2 = 90.1 % ; 83.5%). CONCLUSION: Ultrasonography demonstrates good diagnostic accuracy in the detection of upper and lower limb bone fractures in adults, especially in fractures of the foot and ankle. This is supported by pooled analysis of upper and lower limb fracture subgroups. Further research in larger populations is necessary to validate and strengthen the quality of the available evidence prior to recommending US as a first-line imaging modality for prehospital use. TRIAL REGISTRATION: The protocol is registered with the PROSPERO International register of systematic reviews: ID = CRD42017053640 .

Congenital syphilis presenting with liver lesions.

Congenital syphilis is a prevalent infection in much of the world but rare in contexts where antenatal screening and treatment are available. In the UK in 2016, three cases of congenital syphilis were reported in babies born to women who were seronegative at the time of booking and hence a high degree of clinical vigilance is required in the unwell infant. We present the case of a seven-week-old baby girl with congenital syphilis with the unusual finding of discrete liver lesions. This baby was successfully treated with intravenous ceftriaxone.

A Pilot Study of Infrared Thermal Imaging to Detect Active Bone Lesions in Children With Chronic Nonbacterial Osteomyelitis.

OBJECTIVE: Chronic nonbacterial osteomyelitis (CNO) is an autoinflammatory bone disease. An inexpensive and rapid imaging tool, infrared thermal imaging, was evaluated for its utility to detect active bone lesions in extremities of children with CNO. METHODS: Children with suspected active CNO and healthy controls were enrolled. All subjects underwent infrared thermal imaging of the lower extremities. Patients in the CNO group also received a magnetic resonance imaging (MRI) examination. Hyperintensity within bone marrow on a fluid-sensitive T2-weighted MRI sequence was considered confirmatory for inflammation. Infrared thermal data were analyzed using custom software by dividing the leg below the knee into 3 equal segments longitudinally and adding the distal femur segment as an equal length above the knee. Median and 95th percentile temperatures were recorded for each leg segment. Temperature differences between inflamed and uninflamed segments in all subjects (both intersubject and intrasubject) were evaluated using a linear mixed-effects model. RESULTS: Thirty children in the suspected/known CNO group and 31 healthy children were enrolled. In the healthy control group, males had significantly higher temperature in their lower extremities than females (P < 0.05). There was no difference in temperature detected between inflamed leg segments of patients with CNO versus uninflamed leg segments of the healthy control group. However, within the CNO group, significantly higher temperatures were detected for inflamed versus uninflamed distal tibia/fibula segments (P < 0.01). CONCLUSION: Children with active CNO lesions in the distal tibia/fibula exhibited higher regional temperatures on average than healthy extremities. Larger studies are warranted to further evaluate the clinical utility of infrared thermal imaging for CNO detection.

Improved Surface-Based Registration of CT and Intraoperative 3D Ultrasound of Bones.

The intraoperative registration of preoperative CT volumes is a key process of most computer-assisted orthopedic surgery (CAOS) systems. In this work, is reported a new method for automatic registration of long bones, based on the segmentation of the bone cortical in intraoperative 3D ultrasound images. A bone classifier was developed based on features, obtained from the principal component analysis of the Hessian matrix, of every voxel in an intraoperative ultrasound volume. 3D freehand ultrasound was used for the acquisition of the intraoperative ultrasound volumes. Corresponding bone surface segmentations in ultrasound and preoperative CT imaging were used for the intraoperative registration. Validation on a phantom of the tibia produced encouraging results, with a maximum mean segmentation error of 0.34⁡mm (SD=0.26⁡mm) and a registration accuracy error of 0.64⁡mm (SD=0.49⁡mm).

Coronal plane alignment of the lower limbs in patients with unilateral developmental hip dislocation.

PURPOSE: We aimed to identify the coronal plane alignment of lower limbs in patients with unilateral developmental hip dislocation (UDHD) and observe the difference between Hartofilakidis type II and III. PATIENTS AND METHODS: The radiographic data of 76 patients who met the inclusion criteria were retrospectively reviewed, including the hip-knee-ankle angle (HKA), mechanical lateral distal femoral angle (mLDFA), anatomical lateral distal femoral angle (aLDFA), mechanical proximal tibial angle (MPTA), and lateral distal tibial angle (LDTA). RESULTS: The valgus alignment on ipsilateral side was most frequently seen in both Hartofilakidis type II (51.3%) and type III groups (67.6%), whereas for the contralateral side, the neutral alignment in type II group (69.2%) and varus alignment in type III group (51.4%) were most commonly observed. Both the mLDFA and aLDFA of the ipsilateral side were significantly smaller than the contralateral side. CONCLUSIONS: UDHD patients may present with lower limb malalignment on both sides. The ipsilateral valgus alignment is the most common deformity. On the contralateral side, Hartofilakidis type III patients may be more prone to be varus than type II patients. The lower limb malalignment and deformity of the ipsilateral distal femur should be considered during surgery involving hip, knee, or femur.

Occlusal disharmony-induced stress causes osteopenia of the lumbar vertebrae and long bones in mice.

Excessive exposure to glucocorticoids causes osteoporosis in children and adults. Occlusal disharmony is known to induce an increase in serum corticosteroid levels in murine models, but the influence of occlusal disharmony-induced stress on the bone mass during the growth period has not yet been clarified. The purpose of this study was to investigate whether occlusal disharmony-induced stress decreases bone mass. Five-week-old C57BL/6J male mice were used. A 0.5-mm increase in the vertical height of occlusion was used to induce occlusal disharmony for a period of 7 days. Serum corticosterone levels were significantly higher on post-induction day 7, with radiological evidence of osteopenia of the third lumbar vertebra and long bones of the hind limbs. Osteopenia was associated with a reduction of the mechanical properties of the tibia and femur, with significant suppression of bone formation parameters and an increase in bone resorption parameters, as evaluated by bone histomorphometric analysis of the tibial/femur metaphysis. Our findings at the level of bones were supported by our assessment of serum markers of systemic metabolism. Therefore, occlusal disharmony-induced stress may lead to osteopenia and reduce the mechanical strength of bone through an increase in serum glucocorticoid levels in mice.

SHOX haploinsufficiency presenting with isolated short long bones in the second and third trimester.

Haploinsufficiency of the transcription factor short stature homeobox (SHOX) manifests as a spectrum of clinical phenotypes, ranging from disproportionate short stature and Madelung deformity to isolated short stature. Here, we describe five infants with molecularly confirmed diagnoses of SHOX haploinsufficiency who presented in utero with short long bones during routine antenatal scanning from as early as 19 weeks gestation. Other foetal growth parameters were normal. The molecular basis of SHOX haploinsufficiency was distinct in each case. In four cases, SHOX haploinsufficiency was inherited from a previously undiagnosed parent. In our de novo case, SHOX haploinsufficiency reflected the formation of a derivative sex chromosome during paternal meiosis. Final adult height in the SHOX-deficient parents ranged from -1.9 to -1.2 SDS. All affected parents had disproportionately short limbs and two affected mothers had bilateral Madelung deformity. To our knowledge, SHOX haploinsufficiency has not previously been reported to present in utero. Our experience illustrates that SHOX deficiency should form part of the differential diagnosis of foetal short long bones and suggests a low threshold for genetic testing. This should be particularly targeted at, but not limited to, families with a history of features suggestive of SHOX deficiency. Data on the postnatal growth of our index cases is presented which demonstrates that antenatal presentation of SHOX haploinsufficiency is not indicative of severe postnatal growth restriction. Early identification of SHOX deficiency will enable accurate genetic counselling reflecting a good postnatal outcome and facilitate optimal initiation of growth hormone therapy.

Novel 4-bp Intronic Deletion (c.1560+5_1560+8del) [corrected] in LEMD3 in a Korean Patient With Osteopoikilosis.

Osteopoikilosis is an autosomal dominant bone disorder characterized by symmetric multiple osteosclerotic lesions throughout the axial and appendicular skeleton. Pathogenic variants in the LEMD3 have been identified as the cause of osteopoikilosis. LEMD3 encodes an inner nuclear membrane protein that interacts with bone morphogenetic protein (BMP) and transforming growth factor (TGF)-ß pathways. We report the case of a 19-year-old man presenting with lower back pain and sciatica. His radiograph revealed bilateral and symmetrical multiple osteosclerotic bone lesions in both scapular areas. Sanger sequencing of LEMD3 revealed a four-base-pair deletion in intron 2 (c.1560+5_1560+8del), [corrected] which was inherited from his father. We found that this four-base-pair deletion in intron 2 causes aberrant splicing and consequent deletion of exon 2. To the best of our knowledge, this is the first report of genetically confirmed osteopoikilosis in Korea.

Sex determination using discriminant analysis of upper and lower extremity bones: New approach using the volume and surface area of digital model.

This study used 110 CT images taken from donated Korean cadavers to create 3-D models of the following upper and lower limb bones: the clavicle, scapula, humerus, radius, ulna, hip bone (os coxa), femur, patella (knee cap), tibia, talus, and calcaneus. In addition, the bone volume and surface area were calculated to determine sex differences using discriminant analysis. Significant sex differences were found in all bones with respect to volume and surface area (p<0.01). The order of volume was the same in females and males (femur>hip bone>tibia>humerus>scapula), although the order of surface area was different. The largest surface area in men was the femur and in women was the hip bone (p<0.01). An interesting finding of this study was that the ulna is the bone with the highest accuracy for sex determination (94%). When using the surface area of multiple bones, the maximum accuracy (99.4%) was achieved. The equation was as follows: (discriminant equation of surface area; female<0

Easily Missed Fractures in the Lower Extremity.

As long as radiography remains cheap and provides value in patient care, it will continue to be widely used as a front-line imaging technique. There are limitations to what a radiograph can depict, however. It is imperative to understand the limitations of radiography to avoid pitfalls owing to the overlap of numerous osseous structures. This article reminds the reader of the association between certain radiographic abnormalities and the anatomic relevance in the patient. Although interpretive errors occur in fast-paced, high-volume emergency settings, meticulous attention to changes in the cortex and medullary bone may help to keep errors to a minimum.