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1.
PURPOSE: Conversion of red marrow (RM) to fatty marrow in the skeleton of the lower extremities begins at the distal end, ie, feet, and progresses proximally with distal bone marrow (ie, tibia) being converted more rapidly than proximal bone marrow (ie, femur). However, in an individual long bone, conversion begins in the diaphysis and progresses both distally and proximally (more rapidly toward the distal side). In a normal adult's femur, RM is present in the proximal one third or less. Reconversion of fatty marrow to RM is reported to occur in the reverse order of conversion. We assessed the frequency of various patterns of RM in the adult femur on In-111 leukocyte scans for a better understanding of the bone marrow regeneration process in individual long bones. METHODS: The patterns of marrow activity in the femur shown on In-111 leukocyte scans performed in 354 adults were divided into a) RM limited to the proximal one third or less, b) to the proximal two thirds, c) to the proximal one third and distal one third with no activity in the middle shaft, and d) in the entire femur. RESULTS: There were 207 patients with pattern A, 91 pattern B, 14 pattern C, and 42 pattern D. CONCLUSIONS: A considerably higher number of adults showed pattern B than pattern C. This suggests that regeneration of diaphyseal marrow precedes that of the distal marrow in an individual long bone or possibly that conversion of the latter precedes the former, which is different from that proposed in the literature.  相似文献   

2.
Osteochondroma is a cartilage-capped osseous protrusion that arises from the surface of a bone. Osteochondroma occurs mostly in the metaphysis of long tubular bones such as the femur, tibia, and humerus. Osteochondroma is rare in the diaphysis and in the epiphysis. There was only one case in which a patient had a limited range of motion in the shoulder joint due to an intraarticular osteochondroma of the proximal humerus. We present a rare case of intraarticular osteochondroma involving the proximal humerus with pathologic findings and imaging features on computed tomography and magnetic resonance imaging.  相似文献   

3.
Objectives: Physical exercise is an important factor in the acceleration and maintenance of bone mineral density (BMD). Football is an impact loading sport and some studies demonstrate its site specific, bone mass increasing effect. We compared BMD at different skeletal regions in a group of former professional football players and in normal control subjects and evaluated the effect of demographic factors and time after active career on BMD.

Methods: Twenty four former football players <70 years old who had retired from professional football at least 10 years previously and 25 non-athletic controls were recruited. The demographic characteristics, activity levels, and dietary habits of all subjects and the chronological history of the footballers' professional careers were noted. BMD was measured by DEXA at the calcaneus and distal tibia and at the lumbar spine, proximal femur, and distal and proximal radius, and compared between groups. Stepwise multiple linear regression analysis was used to determine the probable predictors of BMD in former football players.

Results: In former players BMD values were found to be significantly higher at the lumbar spine, femur neck, femur trochanter, distal tibia, and calcaneus, but not at Ward's triangle (femur) or the distal and proximal radius regions compared with controls. Time after active career was the only independent predictor of BMD at the lumbar spine, proximal femur (neck, trochanter, and Ward's triangle), and distal tibia.

Conclusions: Former footballers had higher BMD at weight loaded sites and time after active career seemed to be an important factor in determining BMD.

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4.
Aerobic workout and bone mass in females   总被引:2,自引:0,他引:2  
This cross-sectional study aimed to investigate bone mass in females participating in aerobic workout. Twenty-three females (age 24.1±2.7 years), participating in aerobic workout for about 3 hours/week, were compared with 23 age-, weight- and height-matched non-active females. Areal bone mineral density (BMD) was measured in total body, head, whole dominant humerus, lumbar spine, right femoral neck, Ward's triangle, trochanter femoris, in specific sites in right femur diaphysis, distal femur, proximal tibia and tibial diaphysis, and bone mineral content (BMC) was measured in the whole dominant arm and right leg, using dual energy X-ray absorptiometry. The aerobic workout group had significantly ( P <0.05–0.01) higher BMD in total body (3.7%), lumbar spine (7.8%), femoral neck (11.6%), Ward's triangle (11.7%), trochanter femoris (9.6%), proximal tibia (6.8%) and tibia diaphysis (5.9%) compared to the non-active controls. There were no differences between the groups concerning BMD of the whole dominant humerus, femoral diaphysis, distal femur and BMC and lean mass of the whole dominant arm and right leg. Leaness of the whole dominant arm and leg was correlated to BMC of the whole dominant arm and right leg in both groups. In young females, aerobic workout containing alternating high and low impact movements for the lower body is associated with a higher bone mass in clinically important sites like the lumbar spine and hip, but muscle strengthening exercises like push-ups and soft-glove boxing are not associated with a higher bone mass in the dominant humerus. It appears that there is a skeletal adaptation to the loads of the activity.  相似文献   

5.
Objective To describe the radiographic features of clear cell chondrosarcoma (CCCS), including the computed tomographic (CT) and magnetic resonance (MR) findings, and to correlate them with the histopathologic findings.Design and patients A retrospective review was carried out of 72 patients with histopathologically confirmed CCCS. Imaging studies were available for 34 patients: conventional radiographs (n=28), CT scans (n=14), and MR images (n=15). Radiographic studies were reviewed by three radiologists who rendered a consensus opinion; the studies were correlated with the histopathologic findings.Results Of the 34 patients with imaging studies, 30 were male and 4 were female (mean age 38.6 years; range 11–74 years). Twenty-two lesions were in long bones (15, proximal femur; 1, distal femur; 1, proximal tibia; 5, proximal humerus) and 11 were in flat bones (5, vertebra; 4, rib; 1, scapula; 1, innominate). One lesion occurred in the tarsal navicular bone. Typically, long bone lesions were located in the epimetaphysis (19/22) and were lucent with a well-defined sclerotic margin and no cortical destruction or periosteal new bone formation. More than one-third of the long bone lesions contained matrix mineralization with a characteristic chondroid appearance. Pathologic fractures were present in six long bone lesions (4, humerus; 2, femur). Lesions in the proximal humerus were more likely to have indistinct margins (4/5) and extend into the diaphysis. Flat bone lesions were typically lytic and expansile and occasionally demonstrated areas of cortical disruption. Typically, matrix mineralization, when present, was amorphous. MR imaging, when available, was superior to conventional radiographs for demonstrating the intramedullary extent of a lesion as well as soft tissue extension. CT images better delineated the presence of cortical destruction and the character of matrix mineralization patterns. CCCS lesions were typically low signal intensity on T1-weighted images and moderately or significantly bright on T2-weighted images. Areas of lesion heterogeneity on T1- and T2-weighted images and on post-gadolinium T1-weighted images corresponded pathologically to areas of mineralization, intralesional hemorrhage, and cystic changes. Adjacent bone marrow edema was typically absent (12/15) or only minimally observed in a few cases (3/15). No cases examined with MR imaging demonstrated periosteal new bone formation.Conclusions CCCS typically presents radiographically as a geographic lytic lesion located in the epimetaphyseal region of long bones. Most commonly lesions are found in the proximal femur, followed by the proximal humerus. Lesions within the proximal humerus may exhibit more aggressive features. Lesions in the axial skeleton are typically expansile and destructive, often with soft tissue extension and lack of mineralization. MR imaging may show the presence or absence of bone marrow edema.  相似文献   

6.
Various mechanical forces produce a variable stimulus intensity on bone and have different effects on its growth and development. The aim of this project was to study the effects of a variety of mechanical forces on human humerus morphology. This was investigated by measuring the cortical thickness (cm) and diameter (cm) of the humerus at its proximal, middle and distal thirds from radiographs. The humerus of each of 46 men (five controls, six swimmers, eight gymnasts, seven javelin throwers, nine discus throwers and 11 weightlifters) was radiographed on both right and left sides. The humerus size variation among the participants, in order of increasing size, was found to be as follows: gymnasts, controls, swimmers, javelin throwers, weightlifters and discus throwers respectively. The humeral cortex was largest in the weightlifters, being significantly (P less than 0.05) thicker at distal, medial and proximal sites. The proximal and distal humeral sites in javelin and discus throwers were significantly thicker than those of the control subjects. From the results, static load would seem to provide a higher stimulus to bone than dynamic loading.  相似文献   

7.
Children with an uncomplicated femoral fracture, treated with superimposition of fragments and intentional shortening, usually develop overgrowth of the fractured femur and the ipsilateral tibia which may compensate for the initial shortening and enable the limb in question to reach a length similar to that on the normal side. The overgrowth is evaluated clinically and by scanography. The increased metabolic activity of the growth plates that support this overgrowth has not been documented by any laboratory method. In order to evaluate the metabolic activity of the growth plates, 18 patients (11 males, seven females; mean age 6.1 years) with fractures of the femur were studied at three different time intervals (2-5 months, 6-12 months and 18-24 months). Three-phase bone scintigraphy was performed in all patients. Ten children (five males, five females; mean age 7.5 years) who had had bone imaging for other reasons were used as the control group. Visual analysis of the flow and equilibrium phases was performed for the distal femoral and proximal tibial growth plates. Visual and semi-quantitative analyses of the delayed images were performed for the distal femoral and proximal and distal tibial growth plates. Semi-quantitative analyses yielded the following activity ratios: (a) the distal femoral growth plate of the fractured femur to the contralateral one (FR); (b) the proximal growth plate of the tibia on the side of the fractured femur to the contralateral one (TpR); (c) the distal growth plate of the tibia on the side of the fractured femur to the contralateral one (TdR); and (d) in the control group, the distal growth plates of both femora (FCG) and the proximal (TCGp) and distal (TCGd) growth plates of the tibiae. Visual analysis of the blood flow, equilibrium and delayed images showed increased activity in the distal femoral growth plates during the first and second time intervals, but not during the third. No significant activity changes were found in the proximal and distal tibial growth plates during any of the phases analysed. The mean and standard deviation for FR in the three time intervals were: FRI=1.22+/-0.27, FRII=1.17+/-0.16 and FRIII=1.09+/-0.20. FR values were significantly higher than in the control group (FCG=0.99+/-0.03) (P=0.033). The mean and standard deviation for TpR in the three time intervals were: TpRI=1.08+/-0.18, TpRII=0.94+/-0.09 and TpRIII=0.96+/-0.20. TpR values were not significantly different from those in the control group (TCGp=1.00+/-0.05). However, TpRI was significantly higher than TpRII (P=0.043). The mean and standard deviation for TdR in the three time intervals were: TdRI=1.10+/-0.41, TdRII=1.05+/-0.15 and TdRIII=1.13+/-0.36. TdR values were not significantly higher than in the control group (TCGd=1.00+/-0.04) (P=0.777). These results support the concept that three-phase bone imaging is able to quantify and determine that activation occurs in the distal femoral and proximal tibial growth plates of fractured femora. This phenomenon may explain the overgrowth observed in this injured bone structure.  相似文献   

8.
Repeated measurements of bone mineral density (BMD) by dual-energy x-ray absorptiometry (DEXA) reliably indicate changes in the bone mineral content (BMC) of the lumbar spine and proximal femur, but its applicability to other sites has not been properly determined. The in-vivo day-to-day precision of DEXA (Norland XR-26) for lumbar spine, femoral neck, distal femur, patella, proximal tibia, calcaneus and distal radius was evaluated for 15 subjects who were scanned three times for 2 wk. Intra- and interobserver errors were also determined for image analysis. For clearly defined regions of interest, the following precision values were obtained for BMD with low intra- and interobserver error: 1.7% (lumbar spine), 1.3% (femoral neck), 1.2% (distal femur), 1.0% (patella), 0.7% (proximal tibia), 1.3% (calcaneus) and 1.9% (distal radius). The precision for BMC was lower. The results indicate that DEXA can successfully and precisely measure BMD of sites not commonly assessed by this technique.  相似文献   

9.
10.
An appendicular skeletal response to sodium fluoride (NaF) was detected by total skeletal scintigrams. Twelve postmenopausal osteoporotic women were treated with NaF (88 mg/day) and calcium (1500 mg/day). Total skeletal scintigrams were obtained before and during treatment. Within 4 to 21 mo (mean: 8.3), all 12 patients showed new areas of increased uptake corresponding to metaphyseal regions and short bones of the appendicular skeleton. The number of peripheral bones involved in each subject ranged from four to 12. The most frequently involved sites (11 of 12 patients) were the right distal femur and proximal tibia. Nine patients showed an increase in serum alkaline phosphatase activity, which was attributed to an increase in the skeletal isoenzyme. Seven of 12 patients developed bone pain in one or more of the regions of increased uptake. This study establishes that the skeletal scintigram is a sensitive index of the peripheral skeletal response to NaF.  相似文献   

11.
目的探讨骨原发性恶性纤维组织细胞瘤(BMFH)影像表现及诊断要点。方法回顾性分析6例经病理确诊为BMFH的X线、CT及MRI表现。结果4例侵犯单骨,2例侵犯多骨。溶骨型4例,混合型2例。股骨下端3例,肱骨上端1例,楔骨1例,横突1例,共侵犯12个骨骼。6例均有骨及骨皮质明显破坏,以溶骨性破坏为主,2例病灶周围有轻度骨硬化。全部病例均有软组织肿块,巨大肿块2例,局限性肿块4例,1例肿块内可见散在小钙化影。全部病例未见骨膜反应,3例合并病理性骨折。结论原发性BMFH好发于长骨干骺端或骨端,多见于股骨下端及胫骨上端。虫蚀状或大片状溶骨性骨质破坏,巨大软组织肿块,无骨膜反应,是其影像学特点,诊断需密切结合临床和病理。  相似文献   

12.
Stature estimation is one of the most important parameters for human identification. The current study aimed to investigate the relationship between stature and femur and tibia measurements other than length in modern Thai skeletons, and to derive regression equations that can be used for living stature estimation when complete bones are unavailable. The sample consisted of 159 males and 96 females. We used two analytical methods, i.e. direct 1-step and indirect 2-step. Results showed that the upper breadth of the femur from males and the maximum anteroposterior diameter of the lateral condyle from females were the best estimators of stature. Maximum proximal breadth of the tibia showed the lowest standard error values in males and females. The derived equations were tested on a holdout sample in which the distal breadth of the tibia exhibited the lowest mean absolute error in both males and females, while in the femur measurements, the maximum anteroposterior diameter of the lateral condyle produced the lowest mean absolute error in males, and an absolute mean value from vertical head diameter in females. The present study suggests that measurements taken from damaged bones can be used for stature estimation.  相似文献   

13.
Eight healthy male subjects had intra-cortical bone-pins inserted into the proximal tibia and distal femur. Three reflective markers were attached to each bone-pin and four reflective markers were mounted on the skin of the tibia and thigh, respectively. Roentgen-stereophotogrammetric analysis (RSA) was used to determine the anatomical reference frame of the tibia and femur. Knee joint motion was recorded during walking and cutting using infrared cameras sampling at 120Hz. The kinematics derived from the bone-pin markers were compared with that of the skin-markers. Average rotational errors of up to 4.4 degrees and 13.1 degrees and translational errors of up to 13.0 and 16.1mm were noted for the walk and cut, respectively. Although skin-marker derived kinematics could provide repeatable results this was not representative of the motion of the underlying bones. A standard error of measurement is proposed for the reporting of 3D knee joint kinematics.  相似文献   

14.
目的观察21 d 模拟失重对大鼠胫骨骨形态发生蛋白(BMP)、转化生长因子-β(TGF-β)含量及股骨生长情况的影响.方法雄性SD大鼠14只按体质量配对后随机等分为对照组(CON)和尾部悬吊模拟失重组(TS),21 d实验结束后处死大鼠,取股骨检测物理性状,取胫骨免疫组化法检测BMP、TGF-β变化情况.结果 21 d悬吊期间大鼠生长良好,未出现明显应激反应.21 d模拟失重后大鼠股骨湿重、干重、灰分、直径和密度均显著降低(P<0.01);免疫组化结果显示大鼠胫骨中BMP和TGF-β减少.结论 21 d模拟失重使大鼠后肢骨生长受抑, BMP、TGF-β在局部合成及分泌降低.  相似文献   

15.
Summary

The macroscopic and microscopic distribution of intramuscularly injected, essentially monomeric, 239Pu was studied in the skeleton of the adult tree shrew (Tupaia belangeri). Data for the period between 15 and 50 months after injection are presented and compared with the data from earlier time points. Between 83 and 500 days after injection the nuclide content and the wet weight of the skeleton decreased to a constant level at about 55 per cent of the maximum values. The microscopic distribution has been analysed in distal femora, proximal humerus, proximal tibia and lumbar vertebra over the whole observation time; additionally at some selected time points proximal femur, femur shaft, distal humerus and distal tibia were analysed. The initial endosteal surface activity ranged from 3·8 to 5·3 Bq/cm2 and decreased to a minimum at about 1000 days after injection and increased thereafter. A similar behaviour was found for the dose rate near bone surfaces which was initially about 0·075 Gy/day on endosteal surfaces. In the deep bone and the deep marrow the dose rate was negligible, about 0·008 Gy/day and 0·001 Gy/day, respectively. The average cumulative dose 1500 days after injection was about 67 Gy on the endosteum, six times greater than the cumulative dose calculated from the mean concentration of plutonium in the whole skeleton. All values are normalized to an injected activity of 37 kBq/kg body weight. The tupaia data are discussed in relation to the available data from monkeys, dogs and rats.  相似文献   

16.
Dedifferentiated chondrosarcoma: use of MRI to guide needle biopsy   总被引:4,自引:0,他引:4  
AIM: To describe the use of MRI to identify and biopsy areas of dedifferentiation in patients with a suspected diagnosis of dedifferentiated chondrosarcoma. MATERIALS AND METHODS: Low-grade chondrosarcoma is characterized at magnetic resonance imaging (MRI) as having a lobulate, hyperintense appearance on T2-weighted spin-echo sequences. T2-weighted MR images were assessed in 15 patients with a final pathological diagnosis of dedifferentiated chondrosarcoma for regions of atypical reduced signal intensity. Information regarding the site of ultrasound or computed tomography (CT)-guided biopsy was available in 10 cases. RESULTS: Nine patients were male and six female with a mean age of 60 years (range 25-77 years). The sites involved were the distal femur (n+4) pelvis (n=3) proximal femur (n=4) femoral diaphysis (n=1) proximal humerus (n=2) and proximal tibia (n=1). The dedifferentiated component consisted of osteosarcoma (n=5) malignant fibrous histiocytoma (n=6) spindle cell sarcoma (n=1) leiomyosarcoma (n=1) and pleomorphic sarcoma (n=1). In 14 of the 15 cases, areas of lower signal intensity lacking in lobulation were identified. In nine of the 10 cases, biopsy site included such areas and yielded high-grade sarcoma. CONCLUSIONS: Dedifferentiation within chondrosarcoma may be identified on T2-weighted MRI as areas of reduced signal intensity. These areas should be the preferred site of biopsy.  相似文献   

17.
骨梗死的磁共振成像诊断   总被引:1,自引:0,他引:1  
目的探讨骨梗死的磁共振成像(MRI)表现及其特点,以提高陔病的诊断水平。方法回顷性分析经病理证实或临床随访确诊15例骨梗死的MRI影像特点。结果15例患者总共累及21个部位.股骨下端8个,胫骨上端7个,胫骨下端2个,肱骨上端1个,桡骨下端1个,距骨2个。12例患者MRI表现符合急性骨梗死,2例符合亚急性骨梗死,1例符合慢性骨梗死。21个部位的病变均示松质骨内类圆形或不规则边界清楚的地图状改变。结论MRI是诊断骨梗死最有效方法,不仅能显示早期骨梗死的各种征象,在亚急性期及慢性期MRI均具有特征性表现.且为无创件诊断.是评估骨椰死的最件榆杏片洪  相似文献   

18.
Prolonged exposure of humans and animals to increased pressure as in a disabled submarine (DISSUB) can saturate the body's tissues with dissolved N2 as compressed air is breathed. Decompression-induced bubble formation in the long bone marrow cavity may lead to a bone compartment syndrome resulting in bone ischemia and necrosis. We tested oxygen pre-breathing prior to decompression in sheep to assess the effect upon dysbaric osteonecrosis (DON) induction in a DISSUB simulation experiment. A total of sixteen adult female sheep were used throughout the experiment. Four sheep were used as controls without oxygen pre-breathing. All sheep (99 +/- 14 kg SD) underwent dry chamber air exposure at 60 fsw (2.79 atm abs) (.2827 MPa) for 24 h followed by oxygen (88-92%) pre-breathing (15-min, 1-h, and 2-h and air for control) before "dropout" decompression at 30 fsw/min (0.91 atm/min). 99mTc-methylene diphosphonate (MDP) bone scans of the distal (radii and tibiae) long bones were used to detect "hot spots" of remodeling suggestive of DON lesions. Alizarin complexone fluorochrome was injected to visualize sites of metabolic activity indicating DON repair of both the proximal and distal long bones (radii, tibiae, femora, and humeri). Our findings showed that the amount of alizarin complexone deposition and bone scan uptake was greater in sheep with shorter oxygen pre-breathing times than those undergoing longer pre-breathing dives (p = 0.0056 and p = 0.001, for one and two hour pre-breathes respectively). Proximal limb bones (femur, humerus) displayed less alizarin complexone deposition than the distal radius and tibia (p < 0.0001).  相似文献   

19.
Giant cell tumor (osteoclastoma) of talar bone is a rare entity and is seen more commonly in the third decade of life. We report this disease entity in a 21-year-old male who presented with painful swelling of the left ankle. His conventional radiography revealed an osteolytic lesion in the talus, which was further evaluated using computed tomography and magnetic resonance imaging. Intralesional curettage and autologous bone grafting was performed following which patient's pain and swelling disappeared. Complete range of movement at the ankle joint was regained with minimal restriction of movements at the subtalar joint. There was no evidence of recurrence at 6 months follow up.Giant cell tumor (GCT) is most commonly seen in the distal femur [Stoker DJ. Bone tumors (1): general characteristics benign lesions. In: Grainger RG, Allison DJ, editors. Diagnostic radiology a textbook of medical imaging. 3rd ed. New York: Churchill Livingston; 1997. p. 629–1660], proximal tibia, distal radius and the proximal humerus in descending order of frequency. GCT is [Campanacci M, Baldini N, Boriani S, Sudanese A. Giant cell tumor of bone. J Bone Joint Surg Am 1987; 69:106–14; Wold LE, Swee RG. Giant cell tumor of the small bones of the hand and feet. Semin Diagn Pathol 1984; 1:173–84] uncommon in the small bones of the hand and feet and a very few cases have been reported at these sites. GCT involving the talus is very uncommon and has very rarely been reported. The treatment of choice is intralesional curettage. In recent times, cementing and cryotherapy have increasingly been used with encouraging results. Recurrence is very common in this locally aggressive benign neoplasm.  相似文献   

20.
Multicentric osteosarcoma with long-term survival   总被引:2,自引:0,他引:2  
We present a 14-year-old girl with multicentric osteosarcoma who has survived for over 9 years to date. The patient first noticed right knee pain in 1992. Radiographs showed a destructive and sclerotic lesion of the right distal femur. Similar small sclerotic lesions were seen in the proximal metaphysis of the right femur, proximal site of the right humerus, and mid-posterior of the left humerus. A diagnosis of multicentric osteosarcoma was made on a biopsy of the right distal femur. The sclerotic lesions of the bilateral humeri disappeared after systemic chemotherapy (T-20), and thus wide excisions of the right distal femur and proximal femur were performed in 1993. New lesions appeared in the left iliac bone and the first lumbar vertebra on bone scintigraphy 24 months after the first surgery. Chemotherapy and wide excisions of the left iliac bone and the first lumbar vertebra were performed. The patient was well at the latest follow-up in April 2003, with no evidence of local recurrence or distant metastasis, but recently renal dysfunction appeared.  相似文献   

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