世纪性手术:全髋关节置换术

世纪性手术:全髋关节置换术 前言:该篇文献系去年年初翻译的柳叶刀(新英格兰)的经典文献 现拿出与大家共享 抛砖 引玉 恳请大家指点 这篇文献值得每一个想对髋关节置换深入学习的朋友好好阅读，虽然他没有讲手术技巧，也 没有讲手术指征，但是对历史的回顾和以询证医学的观点来发表自己的看法让大家能对 THR有更深入的了解。 The operation of the century: total hip replacement 世纪性手术:全髋关节置换术 Palaeopathologists have diagnosed osteoarthritis of the hip in ancient skeletons,1 and prevalence and distribution of the disease then seems no different from today.2 However, little more than 100 years ago, the first attempt was made to treat hip arthritis surgically. Interpositional arthroplasty, offered in the late 19th and early 20th centuries, entailed replacing various tissues—including fascia lata, skin, and even the submucosa of pig’s bladder— between the articulating surfaces of the hip. Interposition of a vitallium cup, which covered the reshaped femoral head, by Smith-Peterson in 1938 heralded a new era of arthroplasty.3 考古学家在古代尸体中就发现了髋关节骨性关节炎，其发病率和人群分布特征和现今一致。 但仅仅到100多年以前，才开始外科治疗髋关节关节炎。植入关节成形术起始于19世纪末 20世纪初，在髋关节表面使用了包括阔筋膜、皮肤甚至是猪膀胱的粘膜下层等各种替代物。 1938年Smith-Peterson在整形后的股骨头上植入金属杯，这开启了关节成形术的新纪元。 Wiles developed the first prosthetic total hip replacement in 1938,4 and this implant is regarded as the precedent of the modern genre. Subsequent attempts at reconstruction of destroyed arthritic joints are testimony to the ingenuity of surgeons of that time. These early endeavours were largely betrayed by poor design, inferior materials, and mechanical failure. Charnley revolutionised management of the arthritic hip with the introduction of low friction arthroplasty (figure 1).5 He made three major contributions to the evolution of total hip replacement: 1) the idea of low friction torque arthroplasty; 2) use of acrylic cement to fix components to living bone; and 3) introduction of high-density polyethylene as a bearing material. Reviewing fi rst-generation results of Charnley’s low friction arthroplasty, Berry and colleagues6 and Callaghan and co-workers7 reported 81% and 77% survivorship, respectively, at 25-year follow-up, with revision of any component as the endpoint. Similar data have been reported by other researchers.8–10 These findings lend support to Coventry’s observation in 1991 that “Total hip arthroplasty, indeed, might be the orthopaedic operation of the century”.11 1938年Wiles研究出第一个全髋置换假体，该假体被认为现代假体的先驱。随后为重建病变 严重的骨性关节炎关节进行的各种尝试无疑是当时外科医生智慧的体现。早期的失败大部分 归因于假体设计粗糙，材料本身的不足和力学的失败。Charnley研究出的低摩擦关节成形术 为治疗髋关节骨性关节炎带来***性的进展。其为髋关节置换术带来了3个方面的主要进展: 1)低摩擦关节的理念;2)使用丙烯酸骨水泥将假体固定于宿主骨;3)使用高密度聚乙烯作为 内衬材料。回顾第一代Charnley低摩擦关节的25年生存率，以任一假体翻修为随访终点， Berry和Callaghan分别报道81%和77%的假体生存率，其他研究者也得到了类似的临床结 果。正如Coventry1991年所言，全髋置换术确实是骨科创世纪的手术。 Fender and colleagues reviewed 5-year outcomes of 1198 patients who underwent Charnley’s low friction arthroplasty across one health region in England.12 They recorded a failure rate of nearly 9% and noted that although this proportion was higher than those published from specialist centres, it was probably more representative of the norm. The surgical technique in this series did not adhere uniformly to contemporary cementation philosophy. Failure mechanisms of early total hip replacement included fracture of the implant,13 aseptic loosening as a result of mechanical failure of the fixation interface,14 infection,15 polyethylene wear,16 and dislocation.17 Furthermore, high failure rates were reported in young patients. Fender回顾了英格兰同一卫生地区使用Charnley低摩擦关节的1198名患者，假体5年失败 率接近9%，他们认为虽然该失败率较其他研究中心高，但其可能更接近正常水平。由于不 同时代骨水泥理念不同，该研究中手术技术并不完全相同。THR早期失败原因包括假体骨 折，由于固定失败造成的无菌性松动，感染，聚乙烯杯磨损和关节脱位。此外，年轻患者失 败率较高。 Indications for total hip replacement were initially largely restricted to either elderly and infirm people or individuals with locomotor limitations associated with other comorbidities. However, today, an unacceptable compromise in quality of life constitutes a valid indication for total hip replacement, and patients seek so-called high-performance hips to deliver their expectations and aspirations. Developments in total hip arthroplasty have been directed at reduction of the rate of failure while longevity of the modern patient. Components must, therefore, provide durable fi xation in the face of high stresses, whereas bearing surfaces need to be resilient and show low wear. This Review describes developments of total hip arthroplasty designed to provide a stable and durable implant tailored to meet specific requirements of the individual patient. 由于患者老龄和虚弱的体质或合并其他疾病，早期THR的指征受到极大的限制。而现今， 生活质量受到不可接受的限制就是THR的有效指征，患者需要更好的“髋关节”来满足其 生活期望。虽然现代患者年龄较大，但手术失败率明显减少，这是THR进步的表现。关节 假体必须在高应力下更持久的固定，摩擦界面要有良好的弹性和更低的磨损。本问总结THR 设计上的进步是如何为每个患者提供更稳定、更持久的假体，从而满足他们的个体要求。 Cemented total hip replacement Glück, a German surgeon, was the first researcher to use cement “for a better fixation” of both components of an ivory total knee replacement in 1891.21 However, Charnley introduced and popularised use of polymethyl methacrylate bone cement for fixation of total hip prostheses in the late 1950s.22 Although cemented fixation includes both bone-cement and cement-implant interfaces, the bonecement surface is the one that provides the foundation for durable fixation. Cemented total hip replacement is highly technique-dependent because the surgeon manufactures the bone-cement-implant composite at the time of surgery. 骨水泥THR 1891年，德国外科医生Glück为了更好的固定全膝关节象牙假体，首次使用了骨水泥。 Charnley于19世纪50年代晚期推广使用聚甲基丙烯酸甲酯骨水泥固定全髋关节假体。尽管 骨水泥固定包括骨-骨水泥界面和骨水泥-假体界面，但骨-骨水泥界面才是假体持久固定的基 础。由于骨-骨水泥-假体复合物由外科医生在手术时制成，因此骨水泥THR是与手术技术 高度相关的手术。 Although the chemical composition of bone cement has essentially remained the same over the years, the cementation technique has changed greatly. Early methods entailed limited, if any, preparation of the bone bed; cement was introduced antegrade; and little attempt was made at pressurisation beyond finger-packing. This technique resulted in poor penetration into cancellous bone, inadequate cement mantles, and lamination of the cement. Cement is a grout not a glue: fixation is achieved by mechanical inter lock rather than adhesion. Two groups of researchers23,24 have shown that increased pressurisation of cement enhanced penetration into bone interstices, which was associated with raised tensile and shear strengths at the bone-cement interface. Furthermore, in two separate reports, workers noted that cleaning the endosteal surface contributed to augmented cement intrusion into bone and enhanced the interface shear strength.25,26 Contemporary cementation techniques include cleaning of the endosteal bone with pulsed lavage, retrograde insertion, and sustained pressurisation to optimise micro-interlock. Proximal and distal centralisers facilitate reproducible creation of a complete, uniform, cement mantle.27 The benefits of contemporary cementing techniques have been shown in the Swedish hip register,28 and very good mid-to-long-term results have been published. 尽管骨水泥化学成分数十年来没有变化，但骨水泥技术得到了极大的改进。早期骨水泥技术 有限，没有骨床的准备，骨水泥通过手指顺行挤入，很少得到加压。结果骨水泥很少渗入松 质骨，骨水泥套形成不充分，骨水泥分层明显。该技术时，骨水泥是填充剂而非粘合剂，固 定是通过机械内交锁而非粘附形成。两组研究发现，增加骨水泥注入时压力能够促进骨水泥 渗入松质骨间隙，从而提高骨-骨水泥界面的抗张力和抗剪力强度。此外，两组独立研究发 现，清洗骨床(骨内膜表面)能够促进骨水泥侵入骨间隙从而提高界面的抗剪力强度。现代 骨水泥技术包括脉压冲洗骨内膜界面，逆行注入骨水泥，持续加压以促进骨水泥微交锁作用。 近端和远端的中置器促进形成完全、均匀的骨水泥套。瑞典髋关节登记系统显示，现代骨水 泥技术有着极好的中、长期临床疗效。 Design of the cemented stem embraces two broad ideas: a taper-slip or force-closed design, and a composite-beam or shape-closed design. The taper slip is a highly polished tapered stem designed to settle within the cement mantle and re-engage the taper. Optimisation of load distribution to surrounding bone and cement is achieved by conversion of shear stresses to radial-hoop stresses. By contrast, fixation of the composite beam relies on the shape of the implant and the composite fixation of stem to cement and cement to bone. In the Swedish hip register, 98% survivorship was reported for both the Spectron (Smith & Nephew, Memphis, TN, USA)—a shape-closed design— and the Exeter (Stryker, Newbury, UK)—a taper-slip design—at 9 and 7 years, respectively.19 Williams and colleagues reported 100% survivorship of the Exeter stem at 10-year follow-up, with aseptic loosening as the endpoint.30 After noting that good results over a lengthy follow-up period were needed to identify long-term complications, Wroblewski introduced a third taper from lateral to medial in the C-stem (DePuy, Leeds, UK) believing that it would improve loading and thus bone preservation in the calcar over time (figure 2). He reported 100% survivorship of the C-stem at 7-year follow-up, with aseptic loosening as the endpoint. 骨水泥型假体柄有两种设计理念，力学匹配型和形态匹配型。力学匹配型设计为高抛光的锥 形柄，允许假体柄在骨水泥套中下沉并再度获得稳定性。通过将剪切应力转化为环形放射状 的压应力，假体周围的骨质和骨水泥获得理想的应力分布。与之不同的是，形态匹配型柄的 固定依靠假体柄的形状以及假体-骨水泥和骨水泥-骨化合物的固定。瑞典髋关节登记系统显 示，7-9年随访时，无论是形态解剖型的Spectron柄(Smith & Nephew, Memphis, TN, USA) 还是锥度减小型的Exeter柄(Stryker, Newbury, UK)的假体生存率都达到了98%。Williams报 道，以无菌性松动为随访终点，10年随访期内Exter柄无一例失败。尽管注明需要长期随访 来鉴定长期并发症的发生率，Wroblewski推荐使用第三代锥形柄——C型柄(自外向内形 状)，其认为该柄可以改善应力分布，保存股骨距骨量。以无菌性松动为随访终点，7年随 访时C型柄无一例失败。 The above two fixation ideas demand an adequate and complete cement mantle. In France, the notion evolved of inserting the largest stem possible, by which the rectangular cross-section would provide rotational stability even in the absence of cement. This strategy resulted in the so-called French paradox, whereby good results were reported with oversized stems when the cement mantle was excessively thin or deficient 上述两种固定理念都需要适宜厚度和完整的骨水泥套。但法国学者认为，应该尽可能地选用 最大号股骨假体，即使是周边缺乏骨水泥套其矩形横截面可以提供旋转稳定性。虽然骨水泥 套过薄甚至缺失，这种过大号假体柄的临床疗效也很优越，这种被称为“法国式矛盾”。 Charnley was concerned at the fairly high rate of fracture of his first-generation stems. He recognised that this risk was the result of cantilever bending of a distally well-fixed stem.33 Changing the cross-sectional geometry and dimensions not only produced a much stiffer stem but also changed the design from a taper slip to a composite beam. This alteration introduced different failure mechanisms.34 Although the frequency of stem fracture was reduced, aseptic loosening rose, with an overall increase in rate of failure. Charnley发现第一代假体柄有较高的假体骨折率。其认为这是由于远端固定良好的假体，其 未牢固固定的部分发生弯曲，导致假体断裂。改变假体柄的几何横截面和大小不仅仅使假体 刚度增加同时也将锥度柄改成了混合式柄。这种设计的改变又导致了其他机械原因的失败。 尽管假体骨折率下降了，但松动率的增加导致整体的失败率增加。 Ideas should not be exported from one design to another. In the late 1970s, an Exeter stem was produced with a matt surface. This device had a threefold higher failure rate (10% at 8 years) than its otherwise identical highly polished predecessor.35 Similarly, the design of the Capital Hip (3M Healthcare, Loughborough, UK) was based on the Charnley range but the prescribed surgical technique produced a thin cement mantle. The stainless steel monobloc component worked reasonably well but the modular implant made of titanium was associated with early osteolysis and a high frequency of loosening.36 Even a small change in design can have a substantial effect on long-term outcome. 设计理念不能从一个方向转到另一个方向。在19世纪70年代晚期，Exeter柄被设计成亚光 假体，结果该假体与其他性质完全一致的抛光型假体相比，失败率增加了3倍(8年失败率 为10%)。同样，Capital髋关节假体(3M Healthcare, Loughborough, UK)的设计虽然基于 Charnley假体，但其要求手术时制造相对较薄的骨水泥套。尽管不锈钢整体型假体设计合理， 但由钛制成的组配型假体导致早期骨溶解以及较高的松动率。即使是很小的设计改变也可以 对假体的长期疗效产生重大的影响。 Improvement in cemented fixation of the acetabular component also entails cleaning and drying of the reamed acetabulum and sustained pressurisation of cement. The design of the polyethylene cemented cup has changed little over the decades, although addition of a flange has enhanced pressurisation. Havelin and colleagues,37 analysing the Norwegian arthroplasty register, noted that hydroxyapatite-coated uncemented cups did not perform better than the Charnley cup. Their data should be interpreted with some caution because quality of fixation of the different cementless cups varied greatly 髋臼假体固定方式的改进童谣包括清洗干燥研磨后的髋臼床和骨水泥的持续加压。虽然假体 边缘增加了假体翼以增强骨水泥加压，骨水泥型聚乙烯杯数十年来仅有轻度改进。Havelin 分析挪威关节登记系统数据后认为，与Charnley髋臼杯相比，羟基磷灰石喷涂的非骨水泥 髋臼杯的临床疗效并没有明显的改进。但必须意识到不同非骨水泥髋臼杯的固定质量变化很 大，这对结果会有一定的影响。 Encouraging long-term results of Charnley’s low friction arthroplasty have been reported.6,7 Refinements in stem design that exploit the visco-elastic properties of cement and enhanced cementation techniques have delivered good mid-term results with modern implants. Long-term follow-up of the Exeter device38 suggests that there is no reason why results should not be sustained over time. Recognising the bone-preserving potential of contemporary cemented tapered stems, Spitzer noted that “Cement should not be relegated as an inferior fixation option, but rather should be the fixation of choice in most patients undergoing total hip arthroplasty”. Charnley低摩擦关节的长期临床结果令人鼓舞，现代髋关节假体通过假体设计日趋精细，不 同粘弹性骨水泥，骨水泥技术的提高带来了良好的中期随访结果。Exeter髋关节长期随访结 果显示，其优良的临床效果毫无疑问会长期持续。由于认识到现代骨水泥型锥形柄的保存骨 质的潜力，Spitzer声明:“在髋关节置换术中，骨水泥固定不是一种较低劣的固定方式，而 是大多数患者的良好选择。” Uncemented total hip replacement Early failure of cemented stems implanted by first generation cementation techniques was frequent. These failures were associated with localised areas of bone destruction and resorption (osteolysis). Their cause was initially believed to be infection40 but was subsequently attributed to a local inflammatory response initiated by cement particles. In the 1970s, histological examination of tissue taken from these localised areas of osteolysis showed the presence of polymethyl methacrylate debris,41 and as a result, researchers assumed that premature loosening of cemented components was related to so-called cement disease.42–44 Because of this occurrence, several investigators thought that the future of total hip replacement should be directed towards development of prostheses that could be implanted without use of cement on either the femoral or the acetabular side. Thus, by removing the apparent cause of cement disease (polymethyl methacrylate debris), the primary mechanism of failure of cemented implants might be eliminated. 非骨水泥全髋置换术 以第一代骨水泥技术固定的骨水泥假体早期失败很常见。这些失败伴随着局部区域的骨破坏 和吸收(骨溶解)。最初骨溶解的原因认为是感染，但随后认为是由骨水泥颗粒产生的局部 炎症反应引起。19世纪70年代，局部骨溶解区域行组织活检显示聚乙烯颗粒的存在，结果， 研究者认为骨水泥假体的松动与“骨水泥病”有关。正因如此，需要研究认为THR的未来 应为研究不需要使用骨水泥的关节假体(无论是股骨侧还是髋臼侧)。通过祛除骨水泥病的 明确病因(聚乙烯颗粒)，骨水泥假体早期失败的机制将被消除。 Cementless femoral and acetabular components were designed to provide adequate initial stability and to encourage bone to osseointegrate onto or into the implant. Stems had to be made with either a porous coating of some description or, at the very least, a roughened surface that would allow intimate bony apposition to anchor the implant. Once the implant was biologically stabilised in bone, which could take several months, the femoral component would allow normal transmission of biomechanical forces across the joint 非骨水泥股骨和髋臼假体的设计目的为提供足够的初始固定和促进骨长入假体或长在假体 表面。假体柄有两种类型，一种为含有某些特殊物质多孔喷涂表面，另一种至少有一层粗糙 表面，这些表面能与骨面紧密接触以固定假体。虽然需要数月的时间，一旦假体与骨达到生 物学稳定，股骨假体能正常传导生物应力至关节。 Early designs of femoral porous-coated implants were cylindrical, with extensive coating of the length of the implant. As a result, good diaphyseal bone ingrowth took place, but unfortunately many of these designs were associated with a high rate of cortical atrophy, proximal stress-shielding, and bone loss. Furthermore, patients sometimes complained of thigh pain, presumably due to elastic mismatch between the rigid stem and the biologically flexible femur. 早期设计股骨多孔喷涂假体为全长广泛喷涂的圆柱形假体。其骨干端骨长入良好，但遗憾的 是很多该类假体常发生骨皮质萎缩，近端应力遮挡和骨丢失。并且，病人时常抱怨大腿疼痛， 这可能与刚性假体和生物弹性股骨见弹性模量不匹配有关。 In an attempt to provide enhanced physiological proximal loading of the femur, cementless femoral components were designed that were still cylindrical in shape distally but had a porous ingrowth surface located proximally, in the metaphyseal region. Researchers hoped that biological ingrowth in this area would enhance physiological loading and protect against proximal stress, shielding osteopenia of the femur.47 Some of the early stems did not have circumferential porous coating but rather had patches of this coating located anteriorly and posteriorly as well as medially or laterally. These designs, however, had a high frequency of failure, with large amounts of osteolysis recorded distally. The cause of this osteolysis was believed to be polyethylene particles, which gained access to the distal femur through channels between the areas of porous coating.48 This theory led to development of implants with circumferential proximal porous coating in an attempt to eliminate access channels for particulate debris. 为了增强股骨近端生物学应力，设计了远端圆柱形，干骺端局部多孔骨长入型非骨水泥股骨 假体。设计者希望干骺端的生物学骨长入能够增强局部生理负荷，防止近端应力遮挡和骨质 减少。早期某些假体并没有全周径喷涂多孔表面，而是仅喷涂前方和后方，或者仅喷涂内侧 和外侧。这些假体有很高的假体失败率，伴随假体远端大量骨溶解。该类骨溶解原因确认为 聚乙烯颗粒，其通过多孔表面之间的间隔到达股骨远端。该发现导致近端全周径多孔喷涂表 面假体的发展，试图消除允许颗粒碎屑移动的通道。 In addition to type and location of surface texturing, femoral components vary in shape and by material and mechanical properties. All uncemented femoral stem designs rely on metaphyseal fixation, metaphyseal-diaphyseal junction fixation, diaphyseal fixation, or a combination of the three. Although many stem designs are currently on the market, all fall into three broad designs: anatomic, tapered, or cylindrical. 除了假体表面结构类型的位置的变化以外，股骨假体随着其形状和材料力学特性不断改变。 非骨水泥股骨假体的固定方式分为干骺端固定、干骺端-骨干交界处固定，骨干处固定以及 联合固定。虽然目前市场有很多类型的假体柄，总的来说有三种，解剖型柄、锥形柄和圆柱 形柄。 Anatomic stems, as the name implies, incorporate an anteroposterior curve to match the natural bow of the patient’s femur. These devices were designed around the idea that a curved stem in a curved bone would provide good initial stability and thus subsequently increase bony ingrowth. Researchers hoped that the anatomic design would allow for enhanced physiological loading of the femur and thus reduce stress-shielding and distal thigh pain. Regrettably, however, this outcome was not the case and, indeed, data for most published studies on anatomically shaped stems indicate a higher frequency of thigh pain than with other traditional designs (tapered or cylindrical). 诚如其名，解剖型柄前后向曲度与患者股骨生理性曲度一致。该类柄设计理念认为生理曲度 柄固定于有生理曲度的股骨中能提供极好的初始稳定，随后能促进骨长入。设计者同时希望 解剖型设计能够增强股骨生物应力，从而减少应力遮挡和远端大腿疼痛。遗憾的是事实并非 如此，大部分文献显示与其他两种柄(锥形和圆柱形柄)相比，解剖柄的大腿疼痛发生率更 高。 Tapered stems use proximal cancellous bony ingrowth and three-point stem fi xation to obtain immediate stability. Clinical results of straight tapered stems with at least 10-year follow-up have been good, with stem survivorship reported between 92% and 100% (fi gure 3).51–53 Thigh pain, although occasionally encountered with tapered designs, was largely eliminated when compared with anatomic or cylindrical stems. 锥形柄采用近端松质骨长入和假体柄三点固定获得即使稳定性。直锥形柄的10年随访显示 良好的临床结果，假体生存率为92-100%。虽然锥形柄偶尔并发大腿疼痛，但与解剖柄和环 形柄相比其疼痛率明显减少。 Cylindrical stems need distal cortical support to gain immediate stabilisation. Moreover, distal fixation and osseointegration allow for a greater lever arm to resist torsional forces compared with proximally coated stems. To achieve distal fixation, the prosthesis must be canal-filling, generally needing an implant of large diameter. Stem stiffness depends on the elastic modulus of the material and is proportional to the fourth power of the diameter. Thus, increasing the stem diameter boosts stem stiff ness, a factor that has been linked to distal thigh pain and proximal stress-shielding. The frequency of thigh pain has been reported between 1?9% and 40%. The cause of this pain is related to large stem size, distal porous coating, and material composition.45,46 In a further attempt to lessen stem stiff ness, implants have been designed with coronal slots within the distal third of the stem and longitudinal grooves that can enhance stem strength without increasing the diameter. 环形柄需要远端骨皮质支持以获得即时稳定。以外，与近端喷涂假体柄相比，远端固定和骨 长入能够提供一个更长的力臂来对抗扭转剪力。为了获得远端固定，假体必须完全充填髓腔， 因此一般需要更大直径的假体。假体柄的刚度由制备材料的弹性模量决定且与直径的4次方 成正比。因此增加假体柄的直径会极大的提高假体刚度，而刚度又与远端大腿疼痛和近端应 力遮挡有关。大腿疼痛的发生率为1.9%到40%。大腿疼痛的发生与较大的假体型号，远端 多孔喷涂表面和假体材料组成有关。为了进一步减小假体刚度，在假体远端1/3设计了冠状 槽和纵向沟，这样可以增强假体柄的强度而不用增加其直径。 Although most fully porous-coated tapered stems are made of cobalt chrome, no difference has been recorded in survivorship of stems made of titanium. Titanium has a lower modulus of elasticity—closer to that of host bone—and is more biocompatible than cobalt chrome. On the other hand, titanium is notch-sensitive, which predisposes it to cracks if the stem is not well supported. 尽管大部分全涂层多孔锥形柄由钴镍合金制成，但其与钛金属假体生存率基本一致。钛金属 弹性模量较低，接近宿主骨的弹性模量，生物相容性较钴镍合金更好。此外，钛金属缺口敏 感性较高，在假体柄未得到良好支撑时容易碎裂。 Cementless acetabular cups were introduced to alleviate the difficulty with fixation failure of cemented polyethylene sockets. At 12–15 years, Charnley reported continuous radiolucent demarcation around cemented cups in 14% of patients.40 The failure rate was greatest in young patients, and Barrack and colleagues reported 44% loosening of cemented sockets at 12 years in individuals younger than 50 years.54 Cementless acetabular cups are hemispherical in shape and most are entirely porous-coated for bone ingrowth. Initial stability and fixation can be achieved by press-fit of the component; additional attachment can be provided by pegs, spikes, screws, or a threaded-cup design. Several research groups have noted early failure of the threaded-cup design. 为了减少骨水泥聚乙烯套固定的失败率，推荐使用非骨水泥髋臼杯。术后12-15年时， Charnley在14%患者中发现骨水泥髋臼杯周边存在连续的透亮线。年轻患者中假体失败率最 高，Barrack报道为小于50岁的患者中术后12年时44%发生骨水泥套松动。非骨水泥髋臼 杯为半球型，大部分全层喷涂多孔表面以促进骨长入。假体的初始稳定和固定通过压配式打 入假体获得，可以通过耙齿、钉齿、螺钉或者设计螺纹杯来获得额外的固定。很多研究发现 了螺纹杯假体的早期失败。 Press-fit components avoid the need for screw placement, which carries the added risks of neurovascular injury and fretting wear between screw and shell. Press-fit devices have shown good intermediate results.57 Components inserted with additional screw fixation have 96% survivorship at 10 years. 假体压配式固定避免了螺钉的使用，因为其会导致血管神经损伤以及螺钉和臼杯磨损的风 险。压配式固定假体中期随访结果良好，结合螺钉固定的假体10年生存率为96%。 Failures of cementless cups include accelerated polyethylene wear, malfunction of the locking mechanism of the polyethylene liner in the metal-backed shell,59–62 and extensive periacetabular osteolysis.63 Screw holes in the shell enable debris to access the periacetabular cancellous bone, a further extension of the effective joint space. Modifications to acetabular shells with polished internal surfaces and better locking mechanisms should reduce these complications. Many uncemented components have predominantly fibrous tissue at the fixation interface instead of bony ingrowth.64 Hydroxyapatite has been used to enhance bone ingrowth and stimulate bony gap closure. 非骨水泥型髋臼杯的失败原因包括聚乙烯磨损加速，金属杯中聚乙烯内衬锁定机制失效和广 泛的髋臼周边骨溶解。金属杯中的螺钉孔为碎屑进入髋臼周围松质骨提供了通道和更广的有 效关节容积。髋臼杯的改进包括臼杯内面高抛光和更好的锁定机制，这可以减少相关并发症。 很多非骨水泥假体的固定表面主要是纤维组织长入而非骨长入。应用羟基磷灰石涂层促进骨 长入以及刺激骨空隙闭合。 Long-term results for uncemented total hip arthroplasty are poor compared with its cemented counterpart.68 Medium-term data for patients younger than 50 years are inferior to those for people older than 60 years at time of surgery (figure 4). Data for uncemented stems are good.51,53,69–71 Acetabular component survival is poor: a high proportion of failures is due to polyethylene wear and osteolysis (figure 5). 与骨水泥假体相比，非骨水泥全髋置换长期结果较差。小于50岁年轻患者的中期随访结果 较大于60岁年老患者差。非骨水泥假体柄的生存率良好，而髋臼假体生存率较差，大部分 失败与聚乙烯磨损和骨溶解有关。 Implant stability and fixation are crucial for durability. Research is currently focused on creation of an osteogenic stimulus to enhance bone ongrowth or heal bony defects.72–74 Work in nanotechnology to investigate the effectiveness of incorporating biologically active proteins onto implants to enhance fixation is in its infancy, but if successful it could provide the implant coating of the future. 植入物的初始稳定性和固定对于假体的耐用度至关重要。。目前研究着重于刺激成骨以增强 骨长入和填补骨缺损。用纳米技术将骨生物活性蛋白整合入假体以增强固定效果上不成熟， 未来如果成功讲提供一种新的假体喷涂表面。 Bearing surface The issue of osteolysis has not been resolved by implantation of uncemented components. Lytic defects have been reported with both stable and loose uncemented prostheses.75 In the late 1970s, several researchers76,77 made important initial contributions to knowledge about the role of particles generated by joint prostheses in the pathogenesis of osteolysis and aseptic loosening. Further histological assessment of tissue from these defects indicated that osteolysis was related to the macrophage response to polyethylene debris.48,78–80 Fragments from polyethylene wear, rather than cement particles, were then recognised as the major limitation to conventional total hip arthroplasty. 磨损界面 骨溶解并未因非骨水泥假体的植入得以解决。在稳定的和松动的非骨水泥假体中均发现溶解 性骨缺损。19世纪70年代晚期，很多研究者都发现了由关节假体产生的磨损颗粒在骨溶解 和无菌性松动的发生上起到的作用。骨缺损区域的活检显示骨溶解与聚乙烯颗粒引起的巨噬 细胞反应有关。目前认为，传统THR的主要缺陷为聚乙烯臼产生的磨损颗粒，而非骨水泥 颗粒。 Polyethylene wear and debris formation result in synovitis, joint instability, osteolysis, and prosthesis loosening. Alternative bearing surfaces—such as metal on cross-linked polyethylene and hard-on-hard bearings (metal-on-metal or ceramic-on-ceramic)—have been assessed in an attempt to reduce wear and improve longevity of total hip arthroplasty procedures, especially in young, high-demand, active patients. The introduction of cross-linking of ultrahigh-molecular-weight polyethylene was intended to address the issue of wear and osteolysis by reducing the number of submicron particles generated. Gamma irradiation of polyethylene causes cross-linking, which greatly improves wear resistance compared with conventional polyethylene. Short-term clinical results for cross-linked ultrahigh-molecular-weight polyethylene suggest a reduction in wear versus conventional polyethylene 聚乙烯磨损颗粒导致滑膜炎、关节不稳定、骨溶解和假体松动。更换磨损界面，如金属-交 联聚乙烯和硬对硬界面(金属-金属或陶瓷-陶瓷)能够减少磨损，改善THR的长期有效性， 尤其是对于年轻，生活要求高，运动活跃的患者。推荐使用超高分子交联聚乙烯是为了减少 亚微米磨损颗粒的产生，从而减少磨损和骨溶解。行Gamma射线照射可以使聚乙烯发生交 联，这能极大的提高聚乙烯的耐受性。超高分子交联聚乙烯杯的短期临床结果显示与传统聚 乙烯相比其磨损颗粒产生明显减少。 Metal-on-metal bearing surfaces were first used widely in the 1960s.84–86 Poor materials and designs with equatorial (edge of head diameter) bearing combined with inferior fixation condemned these prostheses to early failure. However, long-term follow-up of implants with polar (central head) bearing showed good survival and little wear without the difficulties associated with polyethylene induced osteolysis.87 This finding led to a resurgence of interest in the in-vitro and in-vivo wear properties of metal-on-metal articulations.88–90 Metal bearing surfaces have low wear rates—in the region of 0?004 mm per year compared with 0?1 mm per year for polyethylene. Metal is not brittle, unlike ceramic, and components therefore do not have to be as thick as ceramic ones do. Thus, for a given acetabular shell size, a large head diameter can be used (fi gure 6), which provides enhanced joint stability and a large range of movement before the neck impinges on the socket. It also produces a fast sliding speed of the bearing, contributing to better lubrication. Metal-on-metal bearings are self-polishing, allowing for self-healing of surface scratches. Although these bearings have the potential for low wear rates, there is concern about generation of metal ions (both cobalt and chromium), which are detectable systemically.91–93 Although raised amounts of cobalt and chromium ions can be recorded in blood and urine, no long-term adverse biological effects have yet been reported. 金属-金属磨损界面最初广泛应用于10世纪60年代。早期粗糙的金属工艺，赤道型臼杯(股 骨头边缘直径)的设计不足以及固定技巧的缺陷常引起假体早期失败。但成功的两极型臼杯 (中心股骨头)假体长期随访显示良好的生存率和极小的磨损率，后者不会导致聚乙烯引发 的骨溶解反应。这些结果重新激起了研究金属-金属关节体内和体外磨损特性的研究。金属 磨损界面磨损率低，约0.004mm/年，而聚乙烯的磨损率为0.1mm/年。与陶瓷不同，金属脆 性不高，所以金属假体比陶瓷假体更薄。因此，同样的髋臼型号，金属假体可以使用更大的 股骨头匹配，这既增强了关节的稳定性，也减少了股骨颈-髋臼缘的撞击而允许更大的活动 范围。金属界面也允许关节滑液更快的流动，从而产生更好的润滑作用。金属-金属为自抛 光界面，表面划痕能够自我修复。尽管该磨损界面有更低的磨损率，但其产生的全身系统可 检测的金属离子(钴和铬金属离子)仍是引起广泛关注。尽管血液和尿液中钴、铬离子浓度 明显增高，但目前尚未发现长期副反应。 Alumina ceramics were introduced in the 1970s. They have a low coefficient of friction, superior wear rates,95 are scratch-resistant, have no potential for ion release, and the particulate debris is not very biologically active.96 However, ceramics do have the potential to fracture because of their brittle nature.97,98 Good short-term results have been reported99 for both alumina-on-alumina and alumina-on-polyethylene couplings. 氧化铝陶瓷假体应用于19世纪70年代，其摩擦系数低，磨损率较金属假体高，良好的耐摩 擦性，无金属离子释放，磨损颗粒生物活性不高，但由于其脆性陶瓷假体容易骨折，文献报 道陶瓷-陶瓷假体和陶瓷-聚乙烯假体短期临床疗效良好。 Oxidised zirconium metal (Oxinium, Smith & Nephew) has been developed, which has the wear resistance of ceramic without the brittle fracture risk.100,101 Findings of clinical studies have yet to provide in-vivo confirmation of the laboratory wear rates achieved. 目前研制出氧化锆假体(Oxinium, Smith & Nephew)，其有陶瓷的耐磨性但没有脆性骨折的风 险。其实验室研究发现磨损率低的特性已经被临床研究体内试验结果证实。 Bone-conserving femoral implants Arthritis of the hip mainly affects articular surfaces of the joint and subchondral bone. Intuitively, resurfacing of the joint is the logical conservative surgical option. Resurfacing prostheses that were popular in the early 1970s had a large diameter head articulating with a cemented polyethylene acetabular component. The polyethylene was very thin, and this aspect—together with the high frictional torque generated by the large diameter head—produced catastrophic wear of the plastic, osteolysis, and implant failure. Early and mid-term failure rates of up to 33% were reported 股骨颈保留型假体 髋关节关节炎主要累计关节表面和软骨下骨。理论上关节表面置换为更合逻辑的手术选择。 流行于19世纪70年代早期的表面置换假体为金属大头与骨水泥型聚乙烯髋臼相关节。聚乙 烯臼很薄，同时金属大头产生很高的摩擦力矩，因此导致髋臼磨损明显增加，骨溶解以及假 体失败。早期和中期的失败率高达33% After recognising the possible bone-conserving benefits of resurfacing arthroplasty, researchers looked into reduction of wear generated at the articular couple. Contemporary metal-on-metal bearings produce very low wear and more than 300 000 have been inserted worldwide over the past 10 years. Exploiting this technology, McMinn showed that acceptable mid-term results could be achieved with metal-on-metal resurfacing and hybrid fixation (cementless cup and cemented femur).106 Treacy and colleagues107 reported 98% survivorship of the Birmingham device (Midland Medical Technologies, Birmingham, UK) at a minimum of 5 years’ follow-up, with revision of either component as the endpoint. 重新认识到关节表面置换术的骨量保存优势后，研究者通过改变关节假体匹配来减少磨损。 现代金属对金属假体界面磨损率极低，近10年来全世界已植入超过30万该种假体。随着假 体工艺的提高，McMinn发现无论是金属-金属假体还是杂交假体(非骨水泥臼杯配合骨水 泥股骨柄)的中期临床结果均令人满意。Treacy报道以任一假体翻修为随访终点，5年随访 期内Birmingham假体(Midland Medical Technologies, Birmingham, UK)假体生存率为98%。 Fracture of the femoral neck remains a major cause for concern. Shimmin and Back108 recorded a 1?46% rate of neck fracture in 3497 Birmingham hips inserted by 89 surgeons in Australia between 1999 and 2004. Factors predisposing to neck fracture included varus placement of the implant and notching of the femoral neck. Amstutz and co-workers109 noted a prevalence of femoral neck fracture of 0?83% in 600 metal-on-metal resurfacing arthroplasty procedures undertaken between 1996 and 2003. They identified failure to cover all reamed bone with the femoral component as the most important factor leading to fracture. 股骨颈骨折仍然是临床热点。Shimmin和Back报道1999-2004年，全澳大利亚89名骨科医 生宫植入3497例Birmingham髋关节假体，股骨颈骨折发生率为1.46%。股骨颈骨折的易感 因素为假体内翻位植入和股骨颈切迹。Amstutz报道1996-2003年60例金属-金属关节表面 置换术中，0.83%发生股骨颈骨折。他们认为假体未完全覆盖研磨股骨颈为股骨颈骨折最重 要的易感因素。 Refinement of implant design and tribological work to optimise the articular couple might further improve results of resurfacing arthroplasty (figure 7). Although this technique is a valuable addition to the surgeon’s repertoire in management of the young active patient with hip disease, early and mid-term results do not justify the unbridled enthusiasm with which the uncritical orthopaedic community has embraced this new technology. Narrowing of the femoral neck can arise, which Beaulé and co-workers110 believe probably indicates an as yet uncharacterised remodelling process that might place the hip at increased risk of fracture over time. Resurfacing is not suitable for all hips,111 and indications and limitations need to be recognised to reduce the number of technique-related failures. 通过假体设计的提高和假体配偶的最佳化来降低关节磨损，关节表面置换的临床疗效将进一 步提高。对于年轻活跃的患者，尽管该技术为手术医生提供了另一项有价值的手术方式，但 其早期和中期结果并不支持无保留的将该技术推荐给未达到的骨科医院。术后可能会出 现股骨颈变窄，Beaulé相信这种非特征性股骨重建提示随着时间的推移髋关节骨折的几率将 逐渐增加。表面置换并不适合所有髋关节，术前应考虑其指征和局限性，从而减少技术相关 的手术失败。 A high rate of failure has been reported with primary cemented total hip replacements in young active individuals.112,113 This finding has led many surgeons to investigate use of cementless fixation in this group of patients. However, fixation or cortical contact of the stem in the diaphysis is associated with distal off loading, which predisposes to stress-shielding and loss of proximal bone stock.114 Furthermore, ever younger cohorts of patients are presenting for total hip arthroplasty.115 These individuals are likely to need revision surgery, and the major challenge facing the surgeon will be loss of bone stock. These factors, together with the idea that minimally invasive surgery should spare both bone and soft tissue, have provided impetus for development of conservative hip implants. 年轻患者中初次骨水泥THR失败率较高，这促使很多外科医生选择非骨水泥假体治疗该类 患者。但股骨干干骺端的固定(骨皮质接触)常伴随远端应力卸载，这导致应力遮挡和近端 骨丢失。此外，更为年轻的患者也开始接受THR治疗，他们极有可能需要关节翻修术，翻 修时外科医生将面临骨缺损的挑战。这些方面与微创手术理念一致，都需要保存骨和软组织， 他们促进了传统髋关节假体的不断发展。 Although several different conservative implants are currently available, few clinical results have been published. The Thrust plate prosthesis was first implanted in 1978 and has subsequently evolved through three generations (figure 8).116 Buergi and colleagues117 reported the clinical and radiological outcome of 102 conservative total hip replacements in which the third generation of Thrust plate was used. Mean follow-up time was 58 months. Survivorship at 5 years was 98%, with revision for aseptic loosening as the endpoint. 尽管目前很多不同的传统型植入物仍在使用，但其临床效果稍有报道。1978年第一例Thrust plate假体应用于临床，随后发展至第三代。Buergi报道了第三代Thrust plate假体在102例 连续病例平均随访58月的临床和放射学结果，以无菌性松动关节翻修为终点，假体5年生 存率为98%。 The Mayo conservative hip is a wedge-shaped device that tapers in both the sagittal and coronal planes. It is curved distally to provide a flat surface for contact with the lateral cortex (fi gure 9). Morrey and co-workers118 described 162 total hip replacements in which this prosthesis was used, with a mean follow-up of 6?2 years. Survival without mechanical loosening was 98?2% at both 5 and 10 years. Mayo假体在矢状位和冠状位均为楔状锥形柄，其远端曲线为假体与外侧骨皮质的紧密接触 提供了平坦的表面。Morrey研究了162例该种假体的临床疗效，平均随访6.2年，以机械性 松动为随访终点，5年和10年的假体生存率为98.2%。 Minimally invasive surgery There is a current trend towards minimally invasive surgery, either through one mini-incision or with a two-incision technique. The claim is that mini-incision procedures reduce pain, blood loss, rehabilitation time, and hospital stay.119 Single-incision surgery—using the same surgical approach as conventional procedures but with a skin incision of less than 10 cm—has been approved by the UK’s National Institute for Clinical Excellence (NICE)120 based on data from two randomised controlled trials.121,122 The two-incision technique is more controversial than single-incision surgery. Proponents claim it reduces soft-tissue trauma.119,123 Compared with the single-incision procedure, the two-incision technique needs more technical expertise, fluoroscopy in theatre, and is associated with a higher complication rate.124 NICE concluded that there was insufficient evidence for the two-incision procedure to be used without special arrangements. 微创手术 无论是一个小切口还是双切口技术，微创手术已是目前的潮流。据称小切口能够减少疼痛和 出血，缩短康复时间和住院天数。根据两组临床随机对照试验数据，英国国家临床优化研究 所(NICE)已经证实，单一小切口的手术路径与传统手术一致，但皮肤切口较传统切口缩 小10cm。双切口技术争议较多，拥护者认为其减少软组织损伤。与单一切口手术相比，双 切口技术需要更多手术经验、影像学配合，且并发症较多。NICE总结认为采用双切口技术 需要特殊培训。 Minimally invasive techniques reduce visualisation for implant positioning. Computer-assisted orthopaedic surgical strategies were developed to enhance placement of implants by conventional methods,126 but they are now used to improve outcome of minimally invasive surgery.127,128 Long-term follow-up is needed to show that the proven durability of total hip replacement is not being lost by compromised exposure. 微创技术导致植入假体时视野不足，计算机辅助系统可以弥补传统方法假体位置精确度不够 的缺陷，目前其用于改进微创手术的临床结果。仍需要长期随访结果确认减少暴露不会影响 THR的长期有效性。 Outcome assessment 30 years ago, the main indications for total hip replacement were pain, disability, or both. Outcome assessment was surgeon-based with hip scores. Charnley’s modification of the Merle d’ Aubigné and Postel score129 and the Harris hip score130 remain two of the most widely used methods. An inherent difficulty of most surgeon-based scoring systems for assessment of outcomes is that they are composite scores, which include clinical and radiological data together with patient-based subjective information. Scores allocated within a criterion are not proportional and cannot then be added together in a meaningful way. 疗效评估 30年，THR的主要指征为疼痛或/和功能障碍。以手术相关髋关节评分为疗效评估。Charnley 改进后的Merle d’Aubigné和Postel评分和Harris髋关节评分仍是目前应用最广泛的评分方 法。大多数评分系统的实行困难在于他们为复合评分，包括临床和放射学资料以及患者主观 信息。应用于各个标准的评分并不是相称的，难以将其以合理的方式整合在一起。 Survivorship analysis, first used in orthopaedics by Dobbs in 1980,131 is a powerful strategy for long-term assessment of replacement arthroplasty. It uses a defined endpoint (revision of implant, etc) and is useful to assess and compare survivorship of different types of implants. The Kaplan-Meier132 method is most frequently used to construct survival plots. Although revision is a reproducible endpoint, it can be affected by extraneous factors such as age or fitness for surgery. Even inclusion of other endpoints such as presence of severe pain, low functional scores, and radiographic evidence of loosening gives no information about patient’s satisfaction or health-related quality of life. There is sometimes substantial disagreement between doctors and patients about health status. 生存率分析，首先在1980年由Dobbs应用于骨科，对THR长期评估的有利手段。其依靠 自己定义随访终点(如假体翻修等等)，对比较不同类型假体生存率非常有效。一般使用 Kaplan-Meier法绘制生存率曲线。尽管翻修是一个可重复的随访终点，但其受到手术时患者 年龄和健康等多种因素的影响。即使加入如严重疼痛，低功能评分以及放射学显示松动等其 他随访终点，也不能为患者的满意度或健康相关生活质量提供信息。对于健康状况的评估患 者和医生常有分歧。 An unacceptable compromise in quality of life represents the main indication for total hip replacement in many individuals presenting today. Thus, only patient-based measures can be used to assess patient’s satisfaction with health-related quality of life postoperatively. 对于当今很多患者，生活质量下降到无法接受时就有了THR的指征。因此，只有以患者为 基础的评分才能评价患者术后与健康相关生活质量的满意度。 Traditionally, generic scales that measure general health status (eg, short form 12)134 and disease-specific scores that assess outcomes important to patients (eg, the Western Ontario and McMaster University osteoarthritis index)135 are used in clinical trials of total hip replacements. Furthermore, site-specific measures have been used as a primary endpoint after surgery. Thus, the Oxford hip score136 is a short, practical, valid, and reliable questionnaire that is sensitive to clinically important changes and is well accepted by patients 通常情况下，用于评价THR相关临床试验的评分标准包括衡量患者基本健康状况的评分(如 SF-12)和对病人预后有重要意义的疾病特异评分(如西安大略和麦克马斯特大学骨性关节 炎评分)。此外，以术后随访终点作为特定疾病的评估方法。因此牛津髋关节评分为一种简 短、实用性强，有效、可信的调查表，其对临床重要症状变化敏感度高并容易被患者接受。 These patient-based assessment methods provide a numerical endpoint that defines clinical outcome. However, they are not patient-specific and do not provide information about what is important to the individual and whether their preoperative expectations have been met. For example, a 65-year-old golfer who remains unable to complete 18 holes after a primary hip replacement might well regard the operation as a failure despite a hip score that would categorise him as good or excellent. Patient’s satisfaction can therefore be poor if expectations are not met. Conversely, a 25-year-old juvenile idiopathic arthritis patient confined to bed or chair whose surgery has restored domestic independence, with commensurate improvement in quality of life, would judge the surgery a great success, despite a very poor hip score. 这些以病人为基础的评估方法有多个决定临床结果的随访终点，但他们都特异性不高，且从 中无法得知每个患者要解决的重点，也无法知道患者术前期望是否得到满足。比如说，一名 65岁高尔夫爱好者，THR术后尽管髋关节评分显示良好或优秀，但由于他仍然无法完成18 洞的比赛，因此他仍然认为手术是失败的。患者术前期望未达到会导致手术满意度低。相反， 若一个25岁年轻患者术前因特发性关节炎只能在床上或轮椅上活动，而手术后能够恢复日 常生活自理，这极大地提高了其生活质量，因此即使髋关节评分很低，但其认为手术获得了 极大的成功。 The personal impact health assessment questionnaire137 was developed to assess the individual effect of disability in patients with rheumatoid arthritis. A similar personalised scoring system is being developed and validated for people with osteoarthritis.138 Wright and colleagues139 have used a somewhat cumbersome patient-generated questionnaire that identifies the main concerns of the individual and how these are affected by surgery. Methods to assess personal effect on disability will not only expose any adverse events or failures associated with surgery but also identify whether realistic expectations discussed preoperatively have been achieved postoperatively. These procedures truly indicate the patient’s assessment of outcome. 个人影响健康评估问卷用于评估类风湿关节炎患者的残疾程度。目前针对骨性关节炎患者已 经研制出一份与之类似并行之有效的个人评分系统。Wright使用一种相对繁琐的患者自答问 卷来查明每个患者手术的主要问题和手术对其的影响。评估个人残疾程度的各种方法不仅能 调查出手术的不利因素或禁忌症，也能鉴定术后患者是否达到了其术前的真实期望。 Discussion Biological resurfacing of the hip joint with engineered tissue is at present no more than a theoretical possibility. Total hip replacement will therefore remain the treatment of choice for arthritis of the hip for the foreseeable future. Both cemented and cementless implants can provide good fixation with favourable long-term results. Today, uncemented prostheses are preferred globally, although this choice is not evidence based and might be less cost effective than cemented implants. 讨论 目前利用组织工程行髋关节生物学表面置换已经不再是理论可能。但可预见的未来中THR 仍然是髋关节关节炎的治疗方法。骨水泥和非骨水泥假体都能提供良好的固定和令人满意的 长期临床效果。尽管非骨水泥假体未得到询证医学支持，价格-效益比也不如骨水泥假体， 但目前全球仍优先选择非骨水泥假体。 Ultrahigh-molecular-weight polyethylene has been the most widely used material for the acetabular bearing. Wear of the polyethylene counterface results in osteolysis and impingement, both of which culminate in aseptic loosening. Harris140 has described the unravelling of the biological process and the prevention of osteolysis. While this optimism is perhaps somewhat premature, durable low-wear articular couples are available today that permit use of large heads to deliver both mobility and stability. Moreover, new drugs are being developed that will prevent osteolysis and loss of bone. As noted, new materials such as Oxinium provide enhanced wear resistance and durability of the articulation. Lappalainen and Santavirta141 have predicted that novel coatings will further improve the longevity of total hip replacements. 绝大多数髋臼假体以超高分子聚乙烯为假体材料。聚乙烯界面磨损导致骨溶解和撞击综合 症，最终发展为无菌性松动。Harris阐明了骨溶解的生理进程和预防措施。尽管最佳选择尚 未出现，但使用大头以提高活动性和稳定性的持久型低摩擦关节目前已得以应用。此外，正 在研发预防骨溶解和骨丢失的各种新药。比如Oxinium研发的增强耐磨性和持久性的新型 关节材料也在不断研发。Lappalainen和Santavirta预计新出现的涂层材料讲进一步提高THR 的生存寿命。 The idea behind minimally invasive surgery embraces both soft-tissue sparing and bone conservation. Conservative femoral implants take less bone at surgery and preserve bone in the long term by providing more physiological loading of the proximal femur. The ability to revise these prostheses to primary standard stems introduces an additional option in the revision programme for the young patient. Furthermore, short stems are easy to insert with minimally invasive surgery, with reduced soft-tissue damage and accelerated rehabilitation. Despite reports of “catastrophic complications of minimally invasive hip surgery”,142 Berry has noted that “It remains difficult to escape the commonsense logic that less invasive operative methods can provide benefits for patients”.143 Short-term gains delivered by this strategy will hopefully not be achieved at the expense of long-term survivorship. 微创手术理念包括减少软组织损伤和保存骨量。保留股骨颈型假体手术时骨量丢失更少，保 留的股骨颈能长期为近端股骨提供更多的生理负荷。年轻患者中将该类假体翻修为以往标准 假体干需采用额外的手术方式。此外，短柄假体更容易在微创手术时插入股骨，从而减少软 组织损伤，加速功能康复。尽管微创髋关节置换术的灾难性并发症偶有报道，Berry发现微 创手术能够为患者带来益处已经达到共识。希望该理念带来的短期收益不是以假体长期生存 率的下降为代价。 Computer-assisted orthopaedic surgery produces better component orientation than the best unaided efforts of the skilled hip surgeon. This technique could reduce the rate of complications (dislocation) and enhance long-term survivorship. Advanced technology has made computer-assisted surgery user friendly.144 Although prospective randomised trials are needed, the reproducible improvement in component orientation that has been shown is likely to lead to widespread use of computer assistance. Patients’ benefit and the unwanted attentions of litigation lawyers are also likely to increase use of computer-assisted surgery in the foreseeable future 即使与经验丰富的髋关节手术医生的传统手术方式相比，计算机辅助手术能够提供更好的假 体定位。该技术能能减少并发症(脱位)以及增加假体长期生存率。技术的改进更能促进计 算机辅助手术的术者互相帮助。尽管需要前瞻性随机研究，易重复的精确假体定位很有可能 推动计算机辅助技术更为广泛的应用。在不久的将来，为了患者的利益和避免律师不必要的 法律起诉，计算机辅助手术将进一步增加。 Patients’expectations after total hip replacement have changed. Today, quality of life issues, which sometimes include high-activity recreational interests, define their aspirations. Modern technology can deliver high-performance hips to accommodate these expectations—but at a cost. Ultimately, health economics will dictate what is both affordable and cost effective in any health-care system 目前患者对THR的期望值有所改变。生活质量问题，有时包括对高活动量的业务爱好的要 求，确定了他们对手术的渴望。现代技术可以提供高质量的髋关节来满足他们的需要，但代 价昂贵。最终，任何卫生保健系统都会详细研究卫生经济学来决定什么是能够负担的，也是 符合成本效益。