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91.
胫骨延长后骨痂直径与新生骨预后关系的临床分析   总被引:1,自引:0,他引:1  
目的探讨胫骨延长后骨痂直径与新生骨预后的关系.方法 1996年1月~2001年12月,对68例胫骨延长者测量达所需延长长度时的骨痂直径,计算骨痂直径率(callus diameter ratios,CDR);统计拆除外固定架后2~4周时新生骨发生骨折例数及畸形角度,比较骨折和成角畸形与CDR的关系.结果拆除外固定架前胫骨前屈角度5度以上畸形19例,其中11例发生骨折;拆除外固定架后胫骨出现5度以上畸形6例,其中2例骨折;其余43例胫骨延长骨痂正常愈合.计算CDR值:CDR值小于80% 23例,其中发生新生骨骨折13例,成角畸形5度以上者21例;CDR在81%~85%之间6例,成角畸形5度以上4例;CDR值超过86% 39例,无畸形或新生骨骨折.结论胫骨延长时CDR小于80%时,容易发生新生骨骨折和畸形;CDR大于85%时,无新生骨骨折和畸形发生;两组间具有统计学意义(P<0.05).CDR是判断骨痂能否正常愈合较为理想的检测指标.  相似文献   
92.
目的寻找一种治疗骨不连接所需植骨材料,利用碱性成纤维细胞生长因子的活性诱导作用,促进骨修复.方法13例成人骨不连患者,选择4-10个月龄胎颅骨(FCB)作可吸收载体,结合碱性成纤维细胞生长因子(bFGF)制备成复合碱性成纤维细胞生长因子胎颅骨(bFGF/FCB),植入受骨区,以适当的内固定重新构建骨修复支架.结果所有患者均得到骨性修复,且成骨效应明显.结论胎颅骨作为植骨材料既可以起到植骨作用,增大植骨面,增加骨再生诱发点,屏蔽了骨断面,也避免了自体植骨的手术创伤;碱性成纤维细胞生长因子可以诱导和促进骨修复,二者复合物是治疗骨不连接的一种较好材料.  相似文献   
93.
Adamantinoma is a rare low-grade malignant bone tumor with an indolent course. The tibia is involved in 85%–90% of long-bone cases. We encountered a patient with primary adamantinoma of the proximal femur. A 60-year-old woman fell and fractured her proximal left femur in the area of a cystic lesion. She underwent an osteosynthesis procedure, and bone union was obtained. After 3 years she developed pain in the left thigh, and a radiographic abnormality was found at the fracture site. A metastatic bone tumor was suspected, and curettage and cementing were carried out. Histologically, we found an epithelial component but failed to detect any primary cancer. Local recurrence became evident after another 6 years. A marginal excision was performed and a bipolar femoral prosthesis was implanted. We finally diagnosed the patient with adamantinoma. In this report we describe the characteristics of this tumor and discuss the reasoning concerning the differential diagnosis and therapeutic plan.  相似文献   
94.
The biocompatibility and osteogenic activity of allogenic decalcified bone matrix (DBM) used as a carrier for bone tissue engineering were studied. Following the method described by Urist, allogenic DBM was made. In vitro, DBM and bone marrow stromal cell (BMSC) from rab-bits were co-cultured for 3-7 days and subjected to HE staining, and a series of histomorphological observations were performed under phase-contrast microscopy and scanning electron microscopy (SEM). In vivo the mixture of DBM/BMSC co-cultured for 3 days was planted into one side of muscules sacrospinalis of rabbits, and the DBM without BMSC was planted into other side as con-trol. Specimens were collected at postoperative week 1, 2 and 4, and subjected to HE staining, and observed under SEM. The results showed during culture in vitro, the BMSCs adherent to the wall of DBM grew, proliferated and had secretive activity. The in vivo experiment revealed that BMSCs and undifferentiated mesenchymal cells in the perivascular region invaded gradually and proliferated together in DBM/BMSC group, and colony-forming units of chondrocytes were found. Osteoblasts,trabecular bone and medullary cavity appeared. The inflammatory reaction around muscles almost disappeared at the second weeks. In pure DBM group, the similar changes appeared from the sur-face of the DBM to center, and the volume of total regenerate bones was less than the DBM/BMSC group at the same time. The results indicated that the mixture of DBM and BMSC had good bio-compatibility and ectopic induced osteogentic activty.  相似文献   
95.
刘忠  杨光  郑建波  余勤  陈兆年 《中华实验外科杂志》2004,26(1):929-930,插图7-4
Objective To investigate the effectiveness and mechanism of transplantation of autol-ogous bone marrow in treating femoral head necrosis. Methods Sixty New Zealand rabbits were randomly divided into groups A,B,and C after establishment of the models of femoral head necrosis. The left femoral head served as the control one,and the right as the experimental group. The mitoxantrone (0.1 mg/kg) with the help of DSA was injected into the femoral head of group A. One ml autologous bone marrow was injected into the femoral head of group B. In group C,mitoxantrone (0. 1 mg/kg) was injected,and 72 h later,1 ml autologous bone marrow was injected. Four months later,all rabbits were killed,and the femoral heads were removed and observed histologically and electron microscopically. Results The number of necrotic osteoclasts in groups A and B showed no significant difference ( P > 0.05 ), ande in group C, the number of necrotic femoral heads at the left and fight sides was 40. 60±4.11 and 21.33±2.16 respec-tively ( P < 0.05 ). At the experimental side of group C, the structure of majority bone cells was clear and intact,and necrosis was occasionally seen. Conclusion At the cellular level, local chemotherapy and au-tologous hematopoietic stem cell transplantation had certain effectiveness for aseptic necrosis of the femoral head.  相似文献   
96.
Dual-energy X-ray absorptiometry (DXA) and quantitative ultrasound (QUS) are the accepted modalities for the evaluation of fracture risk in the clinical setting. However, neither method provides a direct measurement of bone mechanics. In this study, we investigated a prototype device, known as a mechanical response tissue analyzer (MRTA), which provides direct mechanical measurements of mechanical properties of bone. A total of 56 healthy volunteers (20 men and 36 women) between the ages of 18 and 83 were recruited. The MRTA was used to measure the cross-sectional bending stiffness (EI) of the ulna bone. Axial speed of sound (SOS) at the ulna bone was determined by QUS; bone mineral content (BMC) and bone mineral density (BMD) were determined by DXA. Correlations, regression analysis, and analyses of variance (ANOVAs) were used to compare the three modalities. These analyses revealed that although there are strong linear relationships among the data collected by the various technologies, the bone properties reflected by MRTA are not fully explained by DXA and QUS. We conclude that the total information conveyed by MRTA measurements is unique. Further research is needed to delineate the different qualities of bone strength that are captured by MRTA, but not by DXA or QUS.  相似文献   
97.
Digital volume tomography (DVT) is an extension of panoramic tomography. With this diagnostic technique, characterized by high resolution, a narrow section width (0.125 mm) and three-dimensional display, small pathological processes can be well visualized. Twenty-five patients with the history of a progressive hearing loss were examined with DVT (Accu-I-tomo, Morita, Japan). The results were compared with pre- and intraoperative findings to evaluate the diagnostic value of DVT in cases of erosion of the ossicular chain. With high resolution and artifact-free demonstration of the middle ear and the ossicular chain, it was possible to define its continuity preoperatively by DVT in all 25 cases. An intact ossicular chain was found by DVT in 13 cases and was later confirmed by surgery. The predicted erosion of the ossicles was verified in 12 patients, and a tympanoplasty type III was performed. Digital volume tomography is an excellent technique to examine the middle ear cleft and inner ear, and expands the application of diagnostic possibilities in the lateral skull base. Therefore, improvement in preoperative diagnosis is achieved along with more accurate planning of the surgical procedure. Digital volume tomography delivers a small radiation dose with a high resolution and a low purchase price for the equipment.  相似文献   
98.
Wehavereported previouslythatligustrazinecouldpromotehematopoiesisthroughimprovingbonemarrowmicroenvironmentandenhancingadhesive  相似文献   
99.
In 7 patients (5 girls, 2 boys) with the EMG or Wiedemann-Beckwith syndrome, statural growth, bone age (BA), weight and pubertal development were studied longitudinally. Height was above the 90th percentile (%) for chronological age (CA) after age 2 years, reaching an average of 2.5 SD above the mean at or after puberty. Adult or attained height also exceeded significantly (P<0.015) parental (genetic) target height by 13.2 cm on the average. In one girl, adult height prognosis (190 cm) could be reduced to an adult height of 183 cm by high-dose estrogen treatment. In most children, growth velocity remained above the 90th % up to 4–6 years of age and normalized thereafter. In all patients studied, bone age was markedly advanced and particularly so during the first 4 years after birth. Weight was above the 90th–97th % during infancy and early childhood and remained there, appropriate or slightly subnormal for height, until adulthood, except for 3 girls who reached and maintained the 50th % during or after puberty. Spontaneous pubertal development occurred within normal limits for CA and around the 50th % for BA. Except for the marked bone age acceleration, the reason for the increased statural growth and adult height in patients with the EMG syndrome is still unknown.  相似文献   
100.
Bone mineral density (BMD, g/cm2) was measured using dual-photon absorptiometry (DPA) in selected areas of the proximal tibia following uncemented PCA knee prosthesis. In nine patients with 14 alloplastic operations, measurements were taken at 3-6-month intervals for the first 3 1/2 years after operation. There was a significant increase in BMD of about 15% during the first 6 months after operation. The following year it remained increased, although not significantly, compared with the initial values, then gradually diminished. Increased bone density after arthroplasty may be explained mainly by stimulation of bone formation from weight bearing due to improved walking ability. Stress shielding of the proximal part of the supporting tibial bone did not seem to occur.  相似文献   
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