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Climatic and altitude features of living region may affect human body. Many changes in several tissues and organs and several health problems due to climatic and altitude effects were defined in the literature. However, there were limited number of studies which evaluated correlation between development of frontal sinus and climatic/altitude effect. In this study, widths, heights, AP lengths and volumes of frontal sinus were compared by Paranasal CT scans in populations living in Van which has colder climate and higher altitude and Manisa which has milder climate and lower altitude. It was found that widths, antero-posterior lengths and volumes of frontal sinus were higher in populations living in colder climate and higher altitude according to populations living in milder climate and lower altitude. Heights of frontal sinuses were on the contrary of this. These results were found appropriate to increasing of cephalic index in cold climate according to Allen's Rule. We suggest that larger population study should be made with peoples having the same or similar race and genetic structure in different climate and altitude regions and the proportional comparison of frontal sinus measurements with cephalic index should be considered in future studies.
Las características climáticas y de altitud de una región pueden afectar al cuerpo humano. En la literatura se han identificado muchos cambios en varios tejidos y órganos, como así también numerosos problemas de salud debido a los efectos climáticos y de altitud. Sin embargo, existe un número limitado de estudios que han evaluado la correlación entre el desarrollo del seno frontal y el efecto climático / altitud. En este estudio, los anchos, alturas, longitudes antero-posteriores y volúmenes de seno frontal se compararon mediante tomografía computarizada paranasal en poblaciones que viven en Van, que tiene un clima más frío y mayor altitud, y Manisa, que tiene un clima más suave y menor altitud. Se encontró que los anchos, las longitudes antero-posteriores y los volúmenes de los senos frontales eran mayores en poblaciones que vivían en un clima más frío y de mayor altitud respecto a poblaciones que vivían en clima más suave y con menor altitud. En relación a la altura de los senos frontales, se dio la situación contraria a lo anterior. Estos resultados se encontraron adecuados con el aumento del índice cefálico en la región de clima frío, de acuerdo con la Regla de Allen. Sugerimos que se realice un estudio poblacional más amplio con poblaciones de raza y estructura genética iguales o similares en diferentes regiones climáticas y de altitud. La comparación proporcional de las mediciones de los senos frontales con índice cefálico debería considerarse en futuros estudios.
Subject(s)
Humans , Male , Female , Adult , Middle Aged , Aged , Altitude , Climate , Frontal Sinus/diagnostic imaging , Frontal Sinus/growth & development , Age and Sex Distribution , Frontal Sinus/anatomy & histology , Tomography, X-Ray Computed , TurkeyABSTRACT
Pediatric head injury is the leading cause of death and disability,about 40% to 60% of kids of head injury get a CT,and the majority are those with minor head injury,about 10% of these CT scans are positive.Clinical decision rules for pediatric head injury exist to identify children at risk of traumatic brain injury.Those of the highest quality are children's head injury algorithm for the prediction of important clinical events(CHALICE),Pediatric Emergency Care Applied Research Network(PECARN)and the Canadian as-sessment of tomography for childhood head injury(CATCH)clinical decision rules.This review aimed to systematically introduce primary clinical decision rules for children with minor head injury and compare them for diagnostic accuracy in detecting intracranial injury and injury requiring neurosurgery.
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Japan has experienced serious nuclear disaster being a country hit by atomic bombs and as well as the occurrence of recent nuclear plant accidents. On the other hand, the Japanese population is exposed to higher dose of medical radiation compared to other developed countries, which is due to increasing number of diagnostic computed tomography (CT) examinations. The correlation between low-dose radiation exposure and cancer risks has been discussed nationwide since Fukushima nuclear plant accident has occurred, whereas cancer risks due to low-dose ionizing radiation from CT scans have been evident in recent large cohort studies. Though CT scan is a valuable diagnostic tool in medical practice because of its high resolution image with speed of scanning, it is crucial to evaluate whether the use of CT is appropriate weighing the benefits and possible risks. Hospitalist is required to have core competency to improve quality of medical care of the hospital and to coordinate with other departments or co-medical workers. In this regard, we discuss how hospitalist could play a role to justify the use of CT and minimize unnecessary radiological exposure, cooperating with radiologists or radiological technologists.
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Objective To investigate the methods and effects of abdominal and pelvic shielding for pediatric chest CT examinations.Methods The 705-D phantom made by Computerized Imaging Reference Systems (CIRS) was used to replace a 5-year-old child,thermoluminescent dosimeters were set in the abdomen and pelvis to measure the organ and tissue doses.Chest scans were conducted with the routine protocol for pediatric chest CT examinations.Doses to main organs and tissues in the abdomen and pelvis were measured after chest CT scans without lead apron,with lead apron covering anterior of the abdomen and pelvis and with apron wrapping same part,respectively.Results Absorbed doses to some abdominal organs near the irradiation field were up to several mGy in a procedure of pediatric chest CT examination.There were statistically significant differences among the dose values for three different scans at the same location (x2 =16.00,P ＜ 0.05).Statistically significant difference was also found between the dose values for scans,which were measured with wrapping and covering approaches (Z =-2.52,P ＜ 0.05).Compared to the doses in the condition of no shielding,the doses in testis and colon reduced by 71.2％ and 42.3％,respectively,if the abdomen and pelvis was wrapped with a lead apron (0.35 mm Pb),and reduced by 55.9％ and 26.1％,respectively,if the same lead apron was used to cover the anterior of the abdomen and pelvis.Conclusions In pediatric chest CT examinations,the use of a lead apron can effectively shield the abdomen and pelvis,and plays an important role in protection of the gonad and colon.The wrapping measure is worth being recommended.
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PURPOSE: To evaluate airway changes in ovalbumin-induced asthmatic mice in terms of postmortem micro-CT images and pathological findings. METHODS: Asthma was induced in mice by intraperitoneal injection and nasal instillation of ovalbumin aluminium hydroxide into mice (experimental group, n=6), and another group of mice received intraperitoneal injection and nasal instillation of distilled phosphate-buffered saline (control group, n=6). Bronchial lumen area was measured in the main bronchial lumen of the distal third bronchial branch level (6 parts per each mouse) on axial scans of Micro-CT, using a Lucion's smart pen (semi-automated) and a curve pen (manual). Bronchial wall thickness was obtained in 4 sections (2 levels on either side) after the third bronchial branch by measuring the diameter which was perpendicular to the longitudinal axis of the main bronchus on curved Multi-planar reconstruction (MPR) images. Histologic slides were obtained from the lesion that was matched with its CT images, and bronchial wall thicknesses were determined. RESULTS: The mean bronchial lumen area was 0.196+/-0.072 mm2 in the experimental group and 0.243+/-0.116 mm2 in the control group; the difference was significant. Bronchial wall thickness on micro-CT images (mean, 0.119+/-0.01 vs. 0.108+/-0.013 mm) and in pathological specimens (mean, 0.066+/-0.011 vs. 0.041+/-0.009 mm) were thicker in the experimental group than in the control group; bronchial wall thickness on micro-CT images correlated well with pathological thickness (for the experimental group, r=0.712; for the control group, r=0.46). The thick bronchial wall in the experimental group demonstrated submucosal hypertrophy along with goblet cell hyperplasia and smooth muscle hyperplasia. CONCLUSIONS: The results of this study suggest that asthma may induce thickening of bronchial wall and narrowing of the lumen area on micro-CT images and that these results may significantly correlate with pathological findings.
Subject(s)
Animals , Mice , Airway Remodeling , Asthma , Axis, Cervical Vertebra , Bronchi , Case-Control Studies , Evaluation Studies as Topic , Goblet Cells , Hyperplasia , Hypertrophy , Injections, Intraperitoneal , Muscle, Smooth , Ovalbumin , X-Ray MicrotomographyABSTRACT
Objective To measure the hip anatomic parameters and explore the differences between the hip fracture group and the normal group, analyze their effect on the incidence of hip fractures and fracture types by using computer aided design (CAD) and three-dimensional reconstruction technique. Methods Through CT scan images from the lower-extremity of hip fracture patient, the 3D anatomic model was established by Mimics10.01 software, and the 3D anatomic parameters of the normal proximal femur, namely femoral neck anteversion angle (FNAA), neck-shaft angle (NSA), femoral head diameter (FHD), length of femoral neck axis (LFNA) in the lower-extremity were measured. Results The averages of FNAA, NSA, FHD, LFNA in femoral neck fracture group were (7.9±4.6)°, (128.6±4.6)°, (46.0±4.6) mm, (47.1±5.1) mm, and those parameters in intertrochanteric fracture group were (15.5±6.8)°, (134.7±6.9)°, (45.3±3.6) mm, (46.7±3.4) mm. The FNAA and NSA in intertrochanteric fracture group were significantly larger than those in femoral neck fracture group regardless of gender (P<0.01). The FNAA and NSA in both fracture groups showed significant differences as compared with the normal group. ConclusionsThe risk of femoral intertrochanteric fracture will increase when the FNAA is larger than the normal range in Chinese, while the risk of femoral neck fracture will increase when the FNAA is smaller than the normal range in Chinese. The NSA of hip fracture patients was larger as compared with normal Chinese. The larger NSA will lead to a higher risk of femoral intertrochanteric fracture. There exist some differences in anatomic parameters of the proximal femur between the fracture group and the normal group, especially in the angle parameter. The femoral intertrochanteric fractures are more prone to occur in the older people, while the femoral neck fractures are more prone to occur in the younger people.
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Objective To study the modeling method of rat model and the air flow characteristicwith its upper stenosis-airway. Methods Thirty-two 3-month old rats were randomly divided into two groups: the control group and the model group. For the model group, sodium hyaluronte of 0.1 mL was injected into mucosa of the soft palate and uvula in each rat under the anesthetic state. After feeding under the same condition for 3 months, CT scans and respiratory experimental examinations were performed on the two groups, respectively. The computational fluid dynamic (CFD) method was then employed to simulate the airflow in their upper airway. The flow characteristics were compared between the control rat and the model rat. Results (1) The minimum cross-sectional area of pharyngeal in the model group was reduced remarkably than that of the control group, showing that the airway of the model rats was significantly narrower than that of the control rats (P<0.05). (2) The model rats became breathless, and their respiratory period became unsteady. The breath intensity of the model rat on the pharynx fluctuated more rapidly. (3) The maximum wall shear stress on the pharynx of the control rat was scattered at the respiratory phase while it was concentrated for the model rat. Conclusions The injection of sodium hyaluronte into mucosa of the soft palate and the uvula can induced the narrowness of the upper airway in the model rat, which is similar to patients with obstructive sleep apnea-hypopnea syndrome (OSAHS) in pathology. The narrowness of the upper airway can cause dyspnea and extend respiratory period. The shear stress on the pharynx of the upper stenosis-airway induces stronger damage to the pharynx tissue, especially to the soft palate and uvula, which aggravates reconstruction of the pharynx tissue.
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Objective To discuss the method for defining personalized materials properties of the fresh human long bone with alcohol treatment and the effect from the number of bone materials on finite element results. Methods Based on images from CT scans, a three dimensional solid model of the long bone was established in Mimics, which was then classified into the cortical bone, cancellous bone and marrow in Hypermesh. Based on relevant empirical formulas, material parameters of the cortical bone and cancellous bone were given, respectively, and 5 finite element analysis (FEA) models with different numbers of materials were set up. The simulation for linear elasticity of the compression was carried out in Abaqus and the results were validated by in vitro verification test. Results Under the end displacement ranging from 0 to 1 mm, the average relative error between the simulation results and the experimental data for holistic force-displacement was about 10%, when the materials number was defined as 1 kind of the cancellous bone and over 10 kinds of the cortical bone. And the average relative error between the simulation results and the experimental data for the deformation of the measurement points was 14.6%. The error of holistic force displacement for 1 kind of the cortical bone was 2.83% when the end displacement ranged from 0 to 0.5 mm. Conclusions (1) Using the gray value of CT scans, materials properties of the main component of the bone could be defined accurately. (2) The simulation result was greatly affected by the material number of the cortical bone, and defining 10 kinds of the cortical bone could satisfy the FEA need. (3) The FEA model with 1 kind of the cortical bone also could satisfy the need of analysis under small deformation.
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Objective To study the postoperative effects on hearing restoration after different types of ossicular reconstruction with partial ossicular replacement prosthesis (PORP). Methods CT data of the right ear from a healthy volunteer were digitalized and imported into PATRAN software to reconstruct the 3D finite element model of the ear by a self compiling program. Dynamic analysis was conducted on the sound transmission to make comparison between the calculated results and experimental data. Results Results of the dynamic analysis for normal human ear were in good agreement with the experiment data, which confirmed the validity of the FE model. At the frequency between 0.1~10 kHz, hearing restoration with partial retaining the handle of malleus was better than that without retention after the replacement of PORP, and the value of hearing restoration was between 11.56~28.91 dB. The maximum stress of tympanic membrane with partial retaining the handle of malleus was less than that without retaining. At the frequency between 0.1~0.6 kHz as well as between 2~10 kHz, better hearing restoration was obtained when the thickness of the cartilage slice was 2.0 mm. At the frequency between 0.6~2 kHz, better hearing restoration was obtained when the thickness of the cartilage slice was 0.1 mm. Conclusions For ossicular reconstruction with PORP, the effect of retaining the handle of malleus was much better than that without retaining. The effect of hearing restoration was better when the thickness of the cartilage placed between the tympanic membrane and the contact surface of the PORP was within the range of 0.1~2.0 mm.
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Objective To study the role of medial collateral ligament (MCL) in maintaining the stability of the knee joint by constructing the three-dimensional (3D) finite element model of the knee joint. Method sCT scans were performed after the MCL was marked by steel wires and the end point was marked by the dill hole. Then the 3D finite element model of the knee joint including ligaments was constructed with Mimics, Geomagic and Ansys software to simulate the anterior-posterior translation, valgus and internal-external rotation of the knee joint at different flexion angles. Results With the knee at 0, 30, 60, 90 and 120 degree of flexion，the initial stresses of MCL were 4.84, 3.55, 2.17, 1.26 and 0 MPa, respectively. When the knee joint was subjected to anterior translation loading, the stresses were 7.22, 5.78, 4.07, 2.84 and 1.4 MPa, respectively. When the knee joint was subjected to posterior translation loading, the stresses were 8.14, 6.45, 4.19, 2.92 and 1.6 MPa, respectively. When the knee joint was subjected to internal rotation loading, the stresses were 6.81, 5.23, 3.29, 2.25 and 0.97 MPa, respectively. When the knee joint was subjected to external rotation loading, the stresses were 6.28, 5.00, 3.34, 2.21 and 0.82 MPa, respectively. When the knee joint was subjected to valgus loading, the stresses were 11.00, 9.55, 7.25, 5.94 and 3.11MPa, respectively. Conclusions The biomechanical function of MCL can be effectively analyzed by establishing the 3D finite element model of the knee joint to simulate the anterior-posterior translation, valgus and internal-external rotation of the knee joint.
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Objective To develop a novel measurement system composed of micro-CT, mechanical loading device and digital volume correlation (DVC) technique, so as to measure the three-dimensional microstructural deformation field in bone tissue. Methods Uniaxial compression was applied on the specimen with the micromechanical loading device, and CT scans were also conducted while maintaining the same loads; then sequential CT images were matched and searched accordingly by DVC method to calculate the micro-displacement in the specimen along three directions before and after loading; repeated scanning of zero-displacement and rigid body translation were used to evaluate the accuracy and precision of the system. The three-dimensional distribution of displacement field in bovine cancellous bone was measured by the system. Results The result from repeated scanning of zero-displacement showed that the highest accuracy of measurement was performed in the loading direction and the precision was less than tenth of the CT resolution. The result of rigid body translation showed that the standard deviation was 0.001~0.002 μm. For cancellous bone specimen under the load of 600 N, the range of micro-displacement was 100.35~110.25 μm, with multilayer field distribution. Conclusions The accuracy and precision of this measurement system can meet the requirement of DVC method. It is proved that this system can be used for measuring the three-dimensional micro-deformation field in the cancellous bone and as a measurement platform for investigating the relationship between deformation distribution and structural response in bone tissue for the future research.
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Objective To study three-dimensional feature of the thickness of subchondral cortical bone, the surface area and space width of the facet joints as well as its morphological characteristics and variation, and to compare the differences of these parameters in patients with low back pains and healthy people, based on three dimensional reconstruction images of the facet joints. Methods CT scanning from L1/2 to L5/S1 at supine position was performed on 90 subjects to obtain two-dimensional images of the facet joints and three-dimensional point-cloud data of the subchondral cortical bone, the surface area and space width of the facet joints after reconstruction. Distributions of these parameters between the superior and inferior facet joints and at different regions of the articular process were investigated, and differences of these parameters in lumbar segments, gender, age and symptoms were also compared. Results (1)At superior facet, the largest thickness was located at the cranial region, while at inferior facet, it was located at the caudal region. The thickness of subchondral cortical bone was significantly smaller at central region than at the other regions. A more obvious difference could be observed at the lower lumbar levels（L4/5, L5/S1）. (2)The average surface area of the facet joints was (173.2±3.6) mm2, and it was increased with the lumbar level and age increasing, especially at the L4/5 level and at the age of more than 40. The surface area of superior facet joints was significantly larger than that of inferior facet joints for patients with low back pains (except at L5/S1 level), who had an obviously larger surface area of the facet joints than healthy people. (3)The average thickness of space width of the facet joints was (1.46±0.08) mm, and it was decreased with age decreasing, especially at the age of more than 40. The female had significantly larger space width than the male, while patients with low back pains had significantly smaller space width. At each facet joint, the space at cranial region was significantly larger than that at caudal region, and it was also significantly larger at central region than at surrounding region. These differences were more obvious at the lower three lumbar levels. Conclusions Computer-assistant image processing and reconstruction analysis techniques can accurately measure the relative parameters of lumbar facet joints with complicated structure in three dimensional space. The feature of the facet joints was correlated with shape of the facet joint surface，stress on the joint and degeneration of the joint, so it was a reflection of adaptive changes in human body structure due to the long-term loading on the facet joint.
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Objective To conduct the operation of capture and deformation in virtual three-dimensional (3D) environment with force feedback device and simulate the coronary artery bypass operation. Methods Based on data collected from real CT images of the patient with heart disease, digitized visual model of the heart was reconstructed. Then the bypass vessel was built and the vessel model was sculptured by force feedback device to simulate the bypass surgery from pulmonary artery to ventriculus dexter in Fontan operation. Results Space structure of the heart was shown in the virtual 3D reconstructed environment. Bypass vessel with any diameter and angle was transformed to simulate the coronary artery bypass operation. Heart patch with any size was built to repair the heart model. The satisfactory model and parameters of the postoperative model were finally achieved. Conclusions The application of force feedback device in virtual coronary artery bypass operation sets the stage for cardiovascular surgery planning system with mechanical characteristics to simulate multiple modalities of such operation.
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Objective To develop a registration method for 3D human atlas models by using geometric information of the vertices so as to lay a foundation for statistical modeling of atlas. Methods Based on CT images of the normal human, thirty 3D models of human atlases were created and marked by the manual selected points, including 1 standard module, 20 training sets and 9 testing samples. The training sets were first registered with the standard module, including calculation on geometric information of the individual vertex and optimization process of weight coefficients in the registration models. By minimizing the energy function defined with the Euclidean distances between the automatic registered points and the manual selected points in training sets, the optimized weight coefficients could be obtained. The testing samples were then registered with the standard module to calculate the Euclidean distances between the automatic registered points and the manual selected points. The results were then compared with the training sets to evaluate the stability of the registration method. Results The registration function and the corresponding optimized weight coefficients were obtained, and the average errors for the training sets and testing samples were 1.983 mm and 2.045 mm, respectively. Further statistical analysis showed that there were no obvious differences in the error distributions among the training sets and testing samples. Conclusions The accuracy and stability of the proposed registration method meet the requirement in medical applications, and it can provide automatic registration of points of interest on human atlas models and be used for element classification in statistical modeling.
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Objective To establish the model of dentulous mandible and straight wire appliance and investigate the stress and displacement distributions of the roots and periodontal tissues under en masse space closure with sliding mechanics. Methods The three-dimensional finite element model of mandible and teeth was developed from CT images, which consisted of the dentin, enamel, dental pulp, PDL (periodontal ligament), cortical and cancellous bone. The models of Roth straight wire brackets with actual data were also constructed. The dental adhesives were used to stick the brackets on the corresponding teeth. Contact elements were used to simulate the interaction between the stainless steel arch wire and the brackets. Moreover, spring elements were used to connect the brackets and the arch wire. The load with the value of 1 N was applied on the model to close the space. Results The lingual tipping of lateral and central incisors was found, corresponding with the clinical observation of en masse space closure with sliding mechanics. High stress in the teeth and periodontal tissue appeared at the incisors and the distal roots of the first molars. The maximum von Mises stresses in PDL of the central incisors and the distal roots of the first molars were 3.97 kPa and 5.75 kPa, respectively. Conclusions In order to avoid root resorption of incisors, the torque of the brackets could be increased. Less orthodontic forces or orthodontic implant could be used to avoid distal roots of first molars.
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Objective To determine the effects of the two kinds of pedicle screws with cement augmentation used for in vitro sheep osteoporotic vertebra model. Method Forty osteoporosis specimens of lumbar vertebrae demineralized by decalcification solution were complete randomly devided into four groups including Group A (only screw),Group B (whole trajectory filled with PMMA),Group C1(partial trajectory filled with PMMA) and Group C2 (partial trajectory filled with PMMA). Osteoporosis specimens from four groups were tested by bone mineral density (BMD) and observed by spiral CT and MicroCT. The maximum force and energy absorption of pedicle screw were tested. Results BMD in each group were averagely declined about 25%～30% (P>0.05), so osteoporotic vertebrae model was successfully established.Spiral CT and MicroCT showed that screw of Group B was fully surrounded by PMMA, which constituted screw PMMA-bone interface,while screw of Group C2 was partially surrounded by PMMA, which constituted partial screw-bone and partial screw PMMA-bone interface. The axial pull-out test showed that the maximum force (Fmax) and its energy absorption in Group B, C1,2 were significantly higher than those in Group A（P0.05). Conclusions Both the whole and partial pedicle screw augmentation can significantly improve the strength of pedicle screw in the context of osteoporosis. The latter not only formed a special whole interface consisting of partial “screw-bone” and partial screw-CSC-bone interface,but produced the strengthening effect equivalent to the former by increasing injection doses of PMMA.
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Objective To investigate the interface pressure on above knee residual limb at mid stance during walking，so as to provide basis for the establishment of measurement and evaluation system for the above-knee socket. Methods Based on CT images of the femur, soft tissue and above knee socket of the patient with residual limb, the three-dimensional model was first built, and then to assemble them according to changes of the hip joint in a gait cycle. The finite element model was then established to simulate the loading conditions at mid stance during a gait cycle, and the effect of pre-stress was investigated by nonlinear large deformation analysis. Results If considering the effects such as joint changes and pre-stress, the maximum value by calculation for normal interface pressure distributed on the terminal of stump was 257.66 kPa, which could better match the maximum stress actually measured by the Mflex Sensor Distributing System as 258.9 kPa. Conclusions The three-dimensional finite element model with considering the factors such as hip joint change, pre-stress and friction could effectively simulate the stress condition of patient with residual limb during walking.
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Objective To explore biomechanical assessment for the effects on vibration against bone loss by investigating the relationship between material distribution and mechanical properties of rat femur cortical bone based on Micro CT. Methods 35 rats were randomly divided into intermittent vibration groups with the interval of 1, 3, 5, 7 days, and continuous vibration group, respectively. Tail suspended model of disuse osteoporosis was set up. All rats were loaded with mechanical vibration of 35 Hz and 0.3 g, and killed after 8 weeks. Micro CT scanning of the left femur of each rat was performed. Three-dimensional finite element model of the cortical bone was established to calculate the apparent and tissue-level mechanical parameters. Principal components (PCs) were extracted from material distribution, intermittent days and volume fraction by principal components analysis (PCA). Results The PCA revealed the three independent components that could fully explaine the variability of cortical bone characteristics under vibration. The linear regression equations were also created between the material property and the apparent and tissue-level mechanical properties, respectively. Mechanical properties of the cortical bone were influenced by material distribution mostly, and the volume fraction and intermittent days were next in importance. Conclusions The cortical bone material distribution can reflect changes in its mechanical properties, and the bone strength could be assessed by establishing the linear relationship, which could provide a theoretical basis for osteoporosis prevention and treatment as well as the assessment on its rehabilitation process.
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Objective To study changes and correlations in ultrasound acoustic parameters, bone density and microstructure of the cancellous bone at different stages of decalcification. Methods Fifteen defatted porcine cancellous bone specimens were decalcified at different decalcification stages, and the bone density, microstructure and acoustic parameters were measured by Micro CT and ultrasound system, respectively, before and after the decalcification. Correlations between acoustic parameters, bone density and microstructure were investigated. Results With the loss of calcium in bone specimens, BMD (bone mass density), BS/TV and BV/TV decreased continuously. Microstructure parameters SMI and BS/BV increased, while Tb.Th and Tb.N decreased with Tb. Sp increasing. Degree of anisotropy (DA) increased. Acoustic parameter SOS increased at first, and then decreased, with nBUA slightly decreasing. High correlation was found between acoustic parameters, BMD and bone microstructure parameters. Conclusions Ultrasound acoustic parameters are correlated with BMD and bone microstructure. This study may provide some reference information for the early diagnosis of osteoporosis based on ultrasound.
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Relative movement between the spine segments has close connection with spinal surgery. Understanding the spinal range of movement is crucial to advance our understanding about the biomechanical function of spine injury, spinal degeneration, and the development of new surgical treatments and implants for spinal disorders. The measurement of spinal movement has gone through the process from two dimensional plane to three dimensional measurement, from simple to complex, from rough estimation to precise calculation. This paper will describe the major achievements and deficiency of various methods of spinal movement measurement to provide reference and help for the research of spinal movement measurement.