Periosteal osteosarcoma of the femur with bone marrow involvement: A case report

Periosteal osteosarcoma is an exceedingly rare type of chondroblastic osteosarcoma, showing rather better prognosis, and secondary bone marrow involvement is unusual. A case of a 22 year old male with periosteal osteosarcoma of the right femur with an associated bone marrow lesion is presented. The juxtacortical tumor, 16 ×11 × 9 cm, was located on the bone cortex of the upper diaphysis and extended into the surrounding soft tissues. A minimal bone marrow lesion was present, although the bone cortex was quite intact. Microscopically, the tumor consisted exclusively of atypical chondroblastic cells with a small osteoblastic area. The bone marrow lesion, interestingly, contained both multiple nodules of well-differentiated chondrosarcomatous components and a few demarcated foci of atypical spindle cells producing a fine osteoid matrix. It was reasonable to conclude, therefore, that this tumor was a periosteal osteosarcoma with an unusual secondary bone marrow lesion rather than a conventional (central) chondroblastic osteosarcoma with soft tissue invasion. The patients good prognosis with no tumor recurrence or metastasis during more than 7 years follow-up after surgery supports this conclusion.     

股骨近端解剖型钢板在股骨转子间骨折中应用

目的:报告股骨近端解剖型钢板治疗股骨转子间骨折的疗效。方法:应用股骨近端解剖钢板治疗19例股骨转子间骨折,评价治疗结果。结果:19例病人中4个月全部骨性愈合,髋关节屈伸活动恢复95%以上,旋转活动恢复85%,2例轻度髋内翻。结论:股骨近端解剖型钢板治疗转子间骨折具有手术简单,有效,符合生物力学要求,效果满意。     

中国汉族人与美国高加索白人膝关节几何形态的比较

背景:有研究显示中国人膝关节胫骨近端前后径和横径均小于美国高加索人,所以在膝关节形态学方面存在一定差异,因此常发生进口假体系统应用于国人后出现匹配度不高的现象。目的:测量中国人和美国人股骨远端、胫骨近端的几何形态学参数,比较其差异。方法:选择北京清华长庚医院骨科拟行前交叉韧带重建的中国汉族患者50例,以及美国匹兹堡大学运动医学中心拟行前交叉韧带重建的高加索白人后裔患者40例,对90例受试者膝关节进行CT扫描,使用AW Volume Share 5软件进行三维重建,利用Geomagic软件对胫骨近端和股骨远端的各项参数进行测量。结果与结论:①股骨近端测量参数中,中国人的外侧胫骨平台内外径小于美国人(P=0.027),外侧胫骨平台后倾角大于美国人(P<0.05);两组间胫骨平台内外径、内侧胫骨平台外径、内侧胫骨平台前后径、外侧胫骨平台前后径与内侧胫骨平台后倾角比较差异均无显著性意义(P>0.05);②股骨远端测量参数中,中国人的股骨远端横径、外侧髁内外径、内侧髁前后径、外侧髁前后径及髁间窝高度均小于美国人(P<0.05),股骨外翻角大于美国人(P<0.05);两组间内侧髁内外径、髁间窝宽度及滑车沟宽度比较差异无显著性意义(P>0.05);③结果表明,中国人与美国人在膝关节形态学的多个参数存在差异,有必要针对中国人设计更为个体化的膝关节假体。     

股骨远端骨折两种固定方法对比研究

目的 对比应用逆行交锁髓内钉(GSH)和动力髁螺钉(DCS)内固定治疗股骨远端骨折的效果.方法 采用回顾性研究方法对我院自2000年8月～2004年10月治疗的54例股骨远端骨折病例进行对照研究,按A0分类:A1型17例,A2型14例,A3型11例,B1型2例,C1型6例,C2型3例,C3型1例.其中,DCS内固定30例,GSH固定24例.分组统计手术时间,出血量,骨折愈合时间,并发症,膝关节功能.结果 所有病例经5月～2年随访,平均9个月;骨折愈合时间为4.6月(4～9月).DCS固定组平均手术时间1.5小时(1～2.5小时).出血量105 ml(50～200 ml),骨折愈合时间平均4.7月(4～8月),并发症发生5例(发生率16.7%),根据Kolmert膝关节功能评分,优20例,良6例,可4例,优良率为86.6%.GSH固定组手术时间1.8小时(1.5～3.5小时).术中出血量平均120 ml(100～250 ml),平均骨折愈合时间5.1个月(4.5～9个月),并发症发生5例(发生率28%),根据Kolmert膝关节功能评分标准,优15例,良7例,可2例,优良率为91.7%.两组比较,结果无显著差异(P＞0.05) 结论 逆行带锁髓内钉(GSH)及动力髁螺钉(DCS)均是治疗股骨远端骨折的较好方法,但各有其最佳适应症.选择好适应症以及术者技术熟练有利于骨折愈合及关节功能恢复.     

Age‐ and site‐specific decline in insulin‐like growth factor‐I receptor expression is correlated with differential growth plate activity in the mouse hindlimb

The proximal and distal growth plates of the principal long bones do not contribute equally to longitudinal growth. Most forelimb elongation occurs at the shoulder and wrist, while most hindlimb growth occurs at the knee. This study examined whether insulin‐like growth factor‐I (IGF‐I), a potent growth regulator, could underlie this variation via differential receptor expression. The spatiotemporal distribution of the IGF‐I receptor (IGF‐IR) was mapped in hindlimb growth plates (overall and within regional zones) from immature mice using immunohistochemistry. Growth activity was assessed by size/morphology of the growth plate and proliferating cell nuclear antigen (PCNA) expression. Both IGF‐IR and PCNA staining declined considerably with age in the proximal femur and distal tibia (hip and ankle), but expression remained high in the more active distal femur and proximal tibia (knee) throughout growth. Growth plate size decreased with age in all sites, but the absolute and relative decline in IGF‐IR in the hips and ankles of older mice indicated a site‐specific loss of IGF‐I sensitivity in these less active regions. These results suggest that regulation of the IGF‐IR may at least partially mediate differential long bone growth, thereby providing a local mechanism for altering skeletal proportions absent modification of systemic hormone levels. Anat Rec, 2007. © 2007 Wiley‐Liss, Inc.     

Micropuncture studies on the filtration rate of single superficial and juxtamedullary glomeruli in the rat kidney

Summary Single nephron filtration rates of superficial and juxtamedullary nephrons were determined in high and low sodium rats. Single nephron GFR was calculated from TF/P inulin and tubular flow rate in superficial nephrons and single juxtamedullary GFR from corresponding data in long loops of Henle. In low sodium rats superficial nephron GFR was 23.5±6.4 (SD)×10^–6 ml/min×g KW, juxtamedullary nephron GFR was 58.2±13.6 and total kidney GFR (C _In) was 0.94±0.16 ml/min×g KW. Using these single nephron values, total kidney GFR and a total number of 30,000 glomeruli per kidney, the number of superficial and juxtamedullary glomeruli was calculated to be 23,267 and 6,733, respectively. During high sodium diet superficial nephron GFR increased to 38.1±11.3 and single juxtamedullary GFR decreased to 16.5±6.6, total kidney GFR increasing to 1.01±0.24. Calculation again revealed the same distribution of the two nephron types. End-proximal TF/P inulin in superficial nephrons was 2.36±0.36 in low sodium and 2.31±0.28 in high sodium rats. Loops of Henle TF/P inulin and intratubular flow rate were inversely related: the highest TF/P inulin values and lowest intratubular flow rates were found in the descending limb. These data quantify the distribution of superficial and juxtamedullary nephrons on a functional basis and suggest a mechanism by which the kidney adjusts sodium excretion by altering the contribution of each nephron type to total kidney GFR.Supported by the Deutsche Forschungsgemeinschaft and the U.S. Department of the Army, through its European Research Office.     

经皮微创植入锁定钢板治疗胫骨远端骨折

目的探讨应用胫骨远端锁定钢板经皮微创植入治疗胫骨远端骨折的疗效。方法自2010年1月~2012年12月应用小切口植入胫骨远端锁定钢板治疗32例胫骨远端骨折,男19例,女13例,年龄13~77岁,平均39.8岁。其中开放性骨折4例,闭合性骨折28例,均为新鲜骨折。结果 29例获得随访,随访时间6~15个月,平均11.7个月。所有骨折均愈合,平均愈合时间为13.6周,均无感染、骨不连、钢板松动等并发症。按照Mazur踝关节功能评分:优19例,良8例,可2例,优良率为93.1%。结论微创钢板内固定手术创伤小,固定可靠,骨折愈合率高,符合生物学固定原则。     

成人股骨骨髓腔影像解剖学及临床意义

目的 :为研制新型股骨髓内固定器提供解剖学依据。方法 :将 60支成人股骨干燥标本 ,拍摄标准的X线正侧位片 ,观察髓腔的形态 ,测量皮质骨的厚度 ,髓腔的横状径 ,矢状径 ,髓腔的轴线在不同节段与皮质骨内侧缘的切线形成的夹角等。结果 :正位片示髓腔呈“哑铃状” ,自上而下 ,横状径由大 (2 0 .0±0 .3 )mm变小 (11.1± 2 .4)mm ,再由小 (11.1± 2 .4)mm变最大 (3 2 .6± 5 .2 )mm。狭窄段横状径的直方图呈正态分布 ,均数为 (10 .7± 2 .0 )mm。侧位片示髓腔中上段的轴线与中下段的轴线所形成夹角为 (172 .2±2 .2 )° ,其夹角顶端距小转子下缘的实际长度为 (12 .8± 3 .0 )cm。结论 :①髓内钉不适合股骨中下段骨折的髓内固定。②组合式分叉防旋转的髓内钉适合股骨中下段的解剖学特点和力学要求。③顺行击钉 10～ 15cm处时 ,忌用暴力 ,减慢进入速度。     

一种平板流动腔重力灌流系统的力学分析

本文分析了一种采用重力灌流的平板流动腔灌流系统，并根据实验结果确定出相应的阻力系数，获得平板流动腔剪应力、雷诺数以及入口长度与流体重力灌流高度的关系。     

Ouabain decreases apparent potassium-conductance in proximal tubules of the amphibian kidney

According to a previous study from this laboratory, the electrochemical gradient for potassium across the peritubular cell membrane of proximal tubules in the isolated perfused frog kidney increases following the application of ouabain. In order to test, if this phenomenon were due to a decrease of potassium conductance, the effects of ouabain on cell membrane resistances and the sensitivity of the peritubular cell membrane potential difference (PD_pt) to step changes of peritubular potassium and bicarbonate concentration were studied. In the absence of ouabain, PD_pt averaged –60±3 mV (n=25). A step increase of peritubular potassium concentration from 3 to 18 mmol/l (pH 8.07) depolarises PD_pt (PD_k) by +24±2 mV (n=8). An increase of bicarbonate from 20 to 40 mmol/l (pH 8.07) hyperpolarises PD_pt (PD_b) by –2.8±0.4 mV (n=9). The resistance of the luminal and peritubular cell membranes in parallel (R _m) amounts to 45±9 k cm (tubule length) (n=4) and the voltage divider ratio (VDR) to 1.4±0.2 (n=7). The resistance of the cellular cable (cellular core,R _c) approaches 131±37 M/cm (n=4). Peritubular application of 0.1 mmol/l ouabain leads to a gradual decline of PD_pt (t _1/2 approx. 30 min), to an increase ofR _m, a decrease of PD_k and an increase of PD_b. VDR andR _c are not changed significantly. The data point to a functional link between the sodium/potassium ATPase and the potassium conductance of the peritubular cell membrane.