人工股骨头置换术后骨质疏松病因分析

本文观察了１９９０年前施行并获２年民认上随访９９例人工股骨头置换术后患者，对术后假体柄周围骨反应，尤其是股骨大粗隆处骨质疏松的原因，以及骨反应与疼痛的关系进行了分析，认为骨反应与假体在髓腔内的稳定及应力分布有关，由于Ｍｏｏｒｅ型人工股骨头的柄较细，有颈托，负重后应力集中在股骨矩上，导致股骨上粗隆处应力明显减弱，发生废用性骨质疏松，股骨大粗隆质疏松还与使用骨水泥及大粗隆处切骨过多等因素有关，分析中发     

人工股骨头置换术后假体柄断裂的光弹性研究

关节假体柄部断裂在股骨头置换术后并非少见。本实验采用光弹性技术研究模拟人工股骨头假体应力分布，分析人工股骨头假体柄断裂的因素。通过实验研究及８例（９个部位）人工股骨头置换术后假体柄断裂的临床观察，确定其致柄断裂的因素为：①骨水泥的填充和股骨距的截取对假体的应力分布有直接影响；②人工股骨头假体装置不当，如假体内翻或外翻畸形位，均能形成柄部应力集中；③人工股骨头假体一旦出现松动，原装置的假体与股骨上段应力分布发生改变，易导致柄部疲劳断裂。研究资料与临床观察结果为人工股骨头置换术后预防假体柄断裂提供了科学依据     

股骨质量对人工髋关节转换之影响的三维有限元分析

目的 探讨股骨质量对非骨水泥型人工髋关节转换术后稳定性及应力变化的影响。论证三维有限元分析作为个体化假体选择临床前评价手段的可行性及价值。方法 采用三维有限元分析模型,对骨质正常骨与骨质疏松骨进行股骨应力、界面位移的计算,并与实验值比较。结果 正常骨的股骨应力比疏松骨的股骨应力大,非骨水泥有肩托假体（ＮＣＣ）能增加股骨矩处压应力,但同时大粗隆处应力减少。骨质量不同对应力改变的趋势没有影响。骨质量差     

股骨质量对人工髋关节置换之影响的三维有限元分析

目的　探讨股骨质量对非骨水泥型人工髋关节置换术后稳定性及应力变化的影响 ,论证三维有限元分析作为个体化假体选择临床前评价手段的可行性及价值。方法　采用三维有限元分析模型 ,对骨质正常骨与骨质疏松骨进行股骨应力、界面位移的计算 ,并与实验值比较。结果　正常骨的股骨应力比疏松骨的股骨应力大 ,非骨水泥有肩托假体 (NCC)能增加股骨矩处压应力 ,但同时大粗隆处应力减少。骨质量不同对应力改变的趋势没有影响。骨质量差者 ,界面位移大。三维有限元分析结果与生物力学实验结果比较接近。结论　三维有限元分析是目前被认为可以根据病人的股骨质量进行个体化假体选择的有前途的研究方法。骨质量是影响假体的初始稳定性及应力变化的因素     

基于偏髓分型应用骨水泥型长短柄假体置换治疗高龄偏髓Ⅰ型粗隆间骨折的有限元分析（英文）

[目的]探讨高龄偏髓Ⅰ型粗隆间骨折行骨水泥型股骨假体置换术后的股骨应力分布,并对比分析长、短假体柄置换后的应力分布差异。[方法]利用螺旋CT对志愿者的右侧股骨进行断层扫描获取图像数据,将图像数据经Mimics软件和建模软件处理后重建股骨三维模型。在此基础上,建立偏髓Ⅰ型粗隆间骨折长、短柄股骨假体及骨水泥套的三维实体模型,最后利用有限元分析软件建立长、短柄股骨假体治疗粗隆间骨折的三维有限元模型,并对该模型进行生物力学分析。[结果]长、短柄假体置换后股骨的应力分布没有发生明显改变,依然是由近端向远端逐渐增加,至内外侧中下1/3交界处达到峰值,再向末端又减小。短柄假体骨水泥-假体柄界面在末端内外侧虽形成应力集中区,且外侧峰值为15.3 MPa,但未超过骨水泥疲劳强度;而长柄假体在骨水泥-假体柄界面远端内外侧及内侧中段形成应力集中区,其峰值也均低于骨水泥疲劳强度。骨水泥重建的股骨距部位未见明显的应力集中区。[结论]骨水泥型长、短柄假体置换治疗高龄偏髓Ⅰ型粗隆间骨折不会引起股骨应力分布的明显改变。长柄假体的松动概率与短柄假体基本相当,但后者由于手术时间短、创伤小、并发症少,可能更适合治疗高龄偏髓Ⅰ型粗隆间骨折。     

人工髋关节置换术中防治假体周围股骨劈裂

目的探讨人工髋关节置换术术中防治假体周围股骨劈裂的技巧和注意事项。方法回顾分析2009—2013年四川省广安市人民医院骨科完成人工髋关节置换术581例(其中股骨颈骨折171例,股骨头坏死患者357例,骨关节炎患者53例),其中全髋关节置换术421例(金属臼杯全部采用生物型固定,股骨柄假体生物型固定395例,骨水泥型固定26例),股骨头置换术160例(生物型固定83例,骨水泥型固定77例)。术中发生股骨劈裂11例,发生率1.9%。结果 581例患者493例获得1~5年随访,88例患者失访。Harris髋关节疗效系统评价优良率90.1%。发生股骨劈裂的11例(12髋)患者全部获得了1~5年随访,股骨劈裂骨折3~6个月全部愈合,未对患者造成不良影响。Harris髋关节疗效评分系统评价优良率90.9%。结论术中发生股骨劈裂情况几乎都发生在身材相对矮小、股骨髓腔相对狭小的患者,而假体柄远端劈裂者(MayoⅡ型)多几乎都发生在漏斗型髓腔(髓腔开口指数4.7)的患者和采用生物型固定锥形柄的患者。发生股骨劈裂与手术操作有关:扩髓时大转子部位去除骨质不够,髓腔狭小者直扩髓器扩髓不够,股骨柄假体型号大小及类型选择不合适,安装股骨柄假体时过紧未重新扩髓而暴力击入等。     

组合式螺柄人工股骨头的研制及临床应用

针对人工髋关节置换术后假体松动，下沉发生率比较高的特点，作者研制一种新型的人工股骨头，试图减少术后并发症的发生。设计出一种组合式螺纹柄结构的人工股骨头由头颈部和螺柄部组成，假体柄呈圆锥型表面有螺纹，能与髓腔充分接触以减少应力分布。     

股骨近段髓腔重建双动股骨头置换术

[目的]介绍股骨近段髓腔重建双动股骨头置换术治疗高龄骨质疏松股骨颈骨折的手术技术和初步临床效果。[方法] 2015年3月～2019年6月,对92例高龄骨质疏松性股骨颈骨折患者行双动股骨头置换术。经Harding入路显露股骨近端,PFNA主钉作为髓腔中置器,利用自体股骨头碎骨进行颗粒打压植骨,重建股骨近段髓腔,置入相适应的生物型假体柄,完成股骨柄假体置换的生物学固定。[结果] 92例患者均顺利手术,随访8～48个月,获得随访患者80例,3例因摔伤导致假体周围骨折松动,再次行内固定手术。77例患者均愈合良好,无松动,无感染,末次Harris评分(87.93±17.59)分,优良率为84.42%(65/77)。假体下沉2例,骨溶解1例,重度应力遮挡1例。[结论]利用取出的股骨头骨颗粒结合PFNA主钉再造股骨近段髓腔,压配成形,采用常规号生物柄假体完成髋关节置换,该方法对老年骨质疏松股骨颈骨折患者,安全有效,经济实用。     

组合式螺柄人工股骨头的研制及临床应用

针对人工髋关节置换术后假体松动、下沉发生率比较高的特点,作者研制一种新型的人工股骨头,试图减少术后并发症的发生。设计出一种组合式螺纹柄结构的人工股骨头由头颈部和螺柄部组成,假体柄呈圆锥型,表面有螺纹,能与髓腔充分接触以减少应力分布。柄部有2个骨槽,能防止假体柄旋转,头颈部和柄部通过头颈部的8个定位销子和柄部的8个定位孔相连,并用一枚螺丝固定。经生物力学试验,表明该人工关节满足强刚度要求,能形成牢固的生物学固定,松动、移位比较小,经10例手术证实,均无假体松动及下沉发生。作者认为该人工股骨头能减少松动、下沉的发生率,具有应用推广价值。     

生物型假体人工髋关节置换术治疗高龄不稳定股骨粗隆间骨折的股骨距重建

目的探讨生物型假体人工髋关节置换术治疗高龄不稳定股骨粗隆间骨折的手术操作技巧和股骨距重建方法。方法对28例不稳定股骨粗隆间骨折采用生物柄在股骨近端髓腔内的填充作用进行股骨距压迫复位和重建的人工髋关节置换术治疗。手术均采用后外侧入路,在预定平面截断股骨颈,将股骨粗隆部骨折下移复位,利用二锥度生物柄股骨假体顺行击入实现股骨距压迫复位与固定。结果本组术后均获6～48个月(平均22.5个月)随访。28例术后均立即实现了髋臼及股骨柄的生物性压配与初始稳定,术后3个月X线片显示均获骨性固定。术后6个月髋关节Harris评分(90.5±5.3)分,末次随访维持在(93.3±3.1)分。结论对于高龄不稳定股骨粗隆间骨折,股骨颈截骨后股骨粗隆部骨折下移复位变成股骨颈骨折,通过二锥度股骨生物柄假体髓腔内顺行压迫复位与固定,可获得良好的股骨距重建与假体的初始稳定性,加长的股骨柄可增加股骨柄在髓腔内固定范围并可弥补股骨距对假体支撑力的不足。     

髓腔改变对股骨近端假体-骨界面应力的影响

目的 建立股骨近端假体-骨界面应力有限元分析模型.并对中国成年人股骨近端正常受力、翻修过程中扩髓条件下进行静态有限元分析.方法 运用逆向工程与有限元的理论.对CT图像采用了滤波、边界提取、二值化等方法进行处理,所得数据用CAD软件经过曲线重构、曲面重构、实体重构,加工出股骨应力模型.将不同载荷施加与假体-骨界面,改变股骨骨皮质的厚度、假体长度等参数,进行静态模拟应力分析.结果 建立起以国人股骨为基础的有效的假体-骨界面应力分布规律三维有限元模型.股骨的受力主要集中在小转子和大转子之间的股骨距分布区域,并且随着载荷的增加而递增;假体增粗至原来的120%时,股骨最大应力已经接近极限应力值.结论 构建的解剖型股骨假体-骨界面三维有限元模型,几何相似性好.模拟应力分析结果提示接受关节置换的患者应该尽量避免登山等接近加载量极限的活动;对于髓腔骨缺损严重的翻修患者提倡应用骨移植材料.谨慎采用增粗假体固定.     

Loss of bone mass after total hip replacement: preliminary data.

In a total of 37 females with cemented total hip replacement for monolateral coxarthrosis, of which 13 with prosthetic stem loosening, and 11 with monolateral coxarthrosis that is not prosthetized, bone mineral density (BMD) is determined by dual ray photonic absorbimetry selecting regions of interest (ROI) on the cortex of the femurs 4 cm under the lesser trochanter and on the ischium bilaterally. In females that are not prosthetized there are differences in bone mass between the two femurs and the ischium on both sides. In prosthetized patients BMD of the femur and of the ischium on the side operated on is significantly less than on the contralateral one (Student's "t" test: p < 0.001). In patients with stable prostheses, BMD of the femur operated on is greater than that in females with prosthetic stem loosening (Student's "t" test: p < 0.000). Based on a comparison between these two groups we did not observe any other significant differences in BMD among the ROI analyzed. BMD was correlated with the amount of time since surgery only in the ROIs in prosthetized femurs. The study confirms the significant bone resorption of the cortex in prosthetized femurs and documents analogously significant reduction in BMD in the ischium on the side operated on. Finally, it indicates that prosthetic stem loosening may be associated with loss of BMD in the femoral cortex which is significantly greater than that observed, during analogous periods of time in stable implants.     

Bone remodeling after impacted cancellous allograft in revision hip arthroplasty based on <Superscript>99m</Superscript>Tc-MDP bone scintigraphy

Introduction Impacted cancellous allograft for the femur reported by Gie et al. (1993) has resulted in a good outcome. Revascularization of the graft was proven with plain radiographs or in some cases, biopsy and autopsy. We have attempted to document the change in appearance of impacted cancellous allograft in the femur over time on scintigraphic scans.Materials and methods Bone scintigraphy was conducted following total hip arthroplasty of 20 hips without complication using impacted cancellous allograft. At 6 weeks, 1, 2 and 4 years postoperatively, uptake at 5 regions of interest around the femoral component sites was measured.Results At all 5 regions of interest, uptake was significantly decreased at 1 year postoperatively compared with that at 6 weeks postoperatively. At 2 and 4 years postoperatively, uptake was about 2-fold that of the normal femur in the greater trochanter, lesser trochanter, and stem tip and had decreased to almost the normal level at the lateral stem and medial stem.Conclusion In revision hip arthroplasty using impacted cancellous allograft, remodeling of the grafted bone of the femur was still incomplete, particularly at the greater trochanter, lesser trochanter, and stem tip even after 4 years postoperatively. It is felt that further time is required for remodeling.     

Antegrade femoral nailing: an anatomical determination of the correct entry point

Operative problems in the application of femoral locking nails are frequently related to an unfavourable entry point at the greater trochanter. Especially in more distally located fractures the nail is forced to follow the cortex abutted medullary canal. A wrong defined entry point either in the medio-lateral or dorso-ventral direction inevitably leads to tension between nail and femur. Forceful insertion in this situation may cause disastrous iatrogenic comminution at the fracture side or additional fractures at the proximal femur. To avoid tension between nail and femur the best suited entry point must be defined according to the natural medullary cavity.In 16 human cadaver femora, the natural medullary cavity was opened and after cleaning filled with a radio-opaque substance (barium sulphate). Twelve radiographs where taken from each bone starting with the anterior-posterior view and then turning the bone axially in steps of 15 degrees. From these radiographs, the ideal entry point at the greater trochanter was calculated.In 88% of the specimen the ideal entry point for a straight nail was found constantly at the medial border of the greater trochanter overlaying the tendinous insertion of the piriformis muscle. The axis of the medullary cavity was in average 2.1cm anterior to the dorsal border of the greater trochanter.In a second step the ideal entry point for bend nails was calculated. According to this calculation a bend nail with a radius of 100 cm needs an entry point 0.7 mm anterior to the dorsal edge of the greater trochanter. Overlaying the hook like shape of the posterior part of the trochanter.     

Cone prosthesis for the hip joint

The shape of the proximal segment of the femur must be taken into account when implanting femoral endoprostheses, especially those intended for cementless anchorage. Numerous femoral prostheses are available for the proximally broadly extending, "trumpet-shaped" morphology. However, the femur often has a narrow, more cylindrical configuration, as is frequently seen with dysplastic hip joints, but variants of the anatomical constitution or ethnic variants are also found. Conventional femoral prostheses with a proximal transverse oval or rectangular cross-section are often incorrectly positioned in those cases because they can fracture the narrow bones. In many instances, even a pathological anteversion attachment cannot be adequately corrected. The cone prosthesis is ideal for this morphology when pre-operative planning indicates good contact between the bone cortex and the middle third of the prosthetic stem. The tapered anchorage of the cone stem in the medullary cavity reamed to a cone shape promotes primary stability, which is a fundamental prerequisite for the osseointegration of a coarse blasted titanium implant. The sharp longitudinal ridges on the prosthetic stem, which tend to cut into the bone, ensure extensive rotational stability, which explains why thigh pain is not associated with the cone prosthesis. The cone prosthesis has proved its worth in 635 implants performed over 9 years, with highly satisfactory clinical and X-ray results. The surgical technique is relatively straightforward, and complications are rare. The patients' subjective satisfaction is particularly remarkable. The success of the operation lies in correct preoperative planning, which ensures that the morphology of the selected femur guarantees contact between the bone cortex and the middle third of the prosthetic stem.     

Osteolytic changes in the upper femoral shaft following porous-coated hip replacement

Ten uncemented total hip replacements were performed in 1975 using an implant in which the cobalt-chrome femoral stem was coated to give a porous surface. In all but one case a high-density polyethylene head was used. The radiological changes in the upper femoral shafts were assessed between three and nine years later. Seven showed extensive stress-relieving changes, loss of calcar, stress fractures at the root of the lesser trochanter with subsequent detachment, and osteoporosis followed by avulsion of the greater trochanter. In these seven patients the lower part of the stem appeared to be soundly embedded, although in only one was there evidence of bony incorporation. It is suggested that if the fixation of a fully coated implant of this sort remains sound, gross atrophy of the upper femoral shaft develops after five years. This atrophy, associated with an implant which can be removed only at the expense of further bone destruction, presents substantial problems if revision is needed.     

骨水泥型长短柄假体置换治疗高龄粉碎性转子间骨折的三维有限元对比分析

目的 探讨高龄粉碎性转子间骨折行骨水泥型股骨假体置换术后的股骨应力分布,并对比分析长、短假体柄置换后的应力分布差异.方法 利用螺旋CT对志愿者的左侧股骨进行断层扫描获取图像数据,将图像数据经Mimics软件和Unigraphics建模软件处理后重建股骨三维模型.在此基础上,建立粉碎性转子间骨折、长、短柄股骨假体及骨水泥套的三维实体模型,最后利用有限元分析软件ABAQUS6.5建立长、短柄股骨假体治疗粉碎性转子间骨折的三维有限元模型,并对该模型进行生物力学分析.结果 长、短柄假体置换后股骨的应力分布没有发生明显改变,依然是由近端向远端逐渐增加,至内外侧中下1/3交界处达到峰值,再向末端又减小.短柄假体骨水泥-假体柄界面在未端内外侧形成应力集中区,且外侧峰值达21.3 MPa,超过了骨水泥疲劳强度;而长柄假体在骨水泥-假体柄界面远端内外侧及内侧中段形成应力集中区,但其峰值均低于骨水泥疲劳强度.骨水泥重建的股骨距部位未见明显的应力集中区.结论 骨水泥型长、短柄假体置换治疗高龄粉碎性转子间骨折不会引起股骨应力分布的明显改变.长柄假体的松动概率小于短柄假体,前者可能更适合治疗高龄粉碎性转子间骨折.     

Fatty marrow conversion of the proximal femoral metaphysis in transient bone marrow edema syndrome

Introduction In the proximal femoral metaphysis, hematopoietic marrow is predominant during the adult stage of life. The conversion of hematopoietic marrow to fatty marrow in the proximal femoral metaphysis has been suggested as an etiologic factor of ischemia in the pathogenesis of femoral head osteonecrosis. To determine whether the chronology of fatty marrow conversion of the proximal femoral metaphysis is related to transient bone marrow edema syndrome of the hip, a case control study was conducted on 10 patients with the disease.Materials and methods There were 8 men and 2 women with a mean age of 33 years (range 19–45 years). The 10 patients were matched with 20 controls for gender and age (5-year range). T1-weighted MRI scans of their hips were reviewed. Marrow of the greater trochanter becomes fatty before puberty, and thus, the greater trochanter can be used as a built-in control. The signal intensity of the proximal femoral metaphysis was compared to that of the greater trochanter.Results In all patients, the signal intensity of the proximal femoral metaphysis was isointense (fatty marrow) relative to that of the greater trochanter. In control subjects, the signal intensity was isointense in 8 (40%) and hypointense (hematopoietic marrow) in 12 (60%) (p<0.05).Conclusion The current study shows that the proximal femoral metaphysis is predominantly fatty in transient bone marrow edema syndrome. The conversion of hematopoietic to fatty marrow is known to correlate with decreases in intramedullary blood flow. Thus, the current study suggests that an ischemia of the proximal femur secondary to fatty marrow conversion of the proximal femoral metaphysis might be a cause of transient bone marrow edema syndrome of the hip.     

Bone tissue composition varies across anatomic sites in the proximal femur and the iliac crest

The extent to which bone tissue composition varies across anatomic sites in normal or pathologic tissue is largely unknown, although pathologic changes in bone tissue composition are typically assumed to occur throughout the skeleton. Our objective was to compare the composition of normal cortical and trabecular bone tissue across multiple anatomic sites. The composition of cadaveric bone tissue from three anatomic sites was analyzed using Fourier transform infrared imaging: iliac crest (IC), greater trochanter (GT), and subtrochanteric femur (ST). The mean mineral:matrix ratio was 20% greater in the subtrochanteric cortex than in the cortices of the iliac crest (p = 0.004) and the greater trochanter (p = 0.02). There were also trends toward 30% narrower crystallinity distributions in the subtrochanteric cortex than in the greater trochanter (p = 0.10) and 30% wider crystallinity distributions in the subtrochanteric trabeculae than in the greater trochanter (p = 0.054) and the iliac crest (p = 0.11). Thus, the average cortical tissue mineral content and the widths of the distributions of cortical crystal size/perfection differ at the subtrochanteric femur relative to the greater trochanter and the iliac crest. In particular, the cortex of the iliac crest has lower mineral content relative to that of the subtrochanteric femur and may have limited utility as a surrogate for subtrochanteric bone. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 30:700–706, 2012