生物活性骨水泥的孔隙率与骨水泥全髋关节置换术后假体早期位移的相关性研究

[目的]比较全髋关节置换术后早期新型生物活性骨水泥即含锶羟基磷灰石骨水泥(Sr-HA)与传统的聚甲基丙烯酸甲酯骨水泥(PMMA)对假体固定的效果.[方法]从2008年5月～2009年12月在香港玛丽医院行全髋关节置换术的9例(10膝)患者随机分为观察组和对照组,分别使用Sr-HA骨水泥与PMMA骨水泥同定股骨柄,于术后1周、3个月、6个月及12个月随访使用放射立体照相测量分析技术(RSA)测量股骨柄相对于股骨的位移,记录Harris髋关节评分,并于实验室使用显微CT扫描测鼍两种骨水泥的孔隙率进行比较.[结果]所有患者手术经过顺利,无血管神经损伤、肺栓塞等并发症.RSA结果显示Sr-HA组有3例假体的下沉均超过1 mm,而PMMA组假体的下沉全部在1 mm以内.两组患者的Harris髋关节评分在术后均有明显改善.显微CT扫描结果显示Sr-HA骨水泥的孔隙率高于PMMA骨水泥,两者之间差异有统计学意义(P＜0.01).[结论]两组患者术后均无明显临床症状,含锶羟基磷灰石骨水泥相对较高的孔隙率可能是导致全髋关节置换术后早期假体位移的原因.     

加长柄人工股骨头置换术与PFNA内固定治疗高龄不稳定股骨粗隆间骨折的比较研究

目的比较加长柄人工股骨头置换术与股骨近端防旋髓内钉(PFNA)治疗高龄不稳定股骨粗隆间骨折的临床效果。方法回顾性比较分析自2013-06—2014-09诊治的65例高龄不稳定股骨粗隆间骨折,采用PFNA内固定治疗20例(PFNA组),采用加长柄人工股骨头置换术治疗45例(其中骨水泥组22例,生物型组23例)。比较3组手术时间、术中出血量、术后下地时间、并发症发生率,以及术后1、3、6、12个月髋关节功能Harris评分。结果 65例均获得随访9~18个月,平均12个月。3组手术时间差异有统计学意义(P0.05),PFNA组少于生物型组和骨水泥组,而生物型组少于骨水泥组。3组术中出血量差异有统计学意义(P0.05),PFNA组少于生物型组和骨水泥组,而骨水泥组少于生物型组。3组术后下地时间差异有统计学意义(P0.05),生物型组和骨水泥组明显早于PFNA组,而骨水泥组早于生物型组。生物型组和骨水泥组术后1、3、6个月髋关节功能Harris评分均优于PFNA组,但生物型组与骨水泥组比较差异无统计学意义(P0.05);术后12个月时3组髋关节功能Harris评分差异无统计学意义(P0.05)。结论对于身体状况较好、骨质稳定的高龄股骨粗隆间骨折,可首选PFNA髓内固定;对于伴有严重骨质疏松,不适合内固定治疗以及内固定失败,或预期置换后关节使用年限不长患者,加长柄人工股骨头置换术是安全、有效的手术方式。     

The effect of two different types of cement restrictors on the femoral cement mantle

Cement restriction and pressurisation are helpful technical points in achieving a good cement mantle in cemented hip replacement. In this prospective study, we compared 39 cases where a Hardinge polyethylene restrictor was used and 33 cases where a bone block restrictor was used during Charnley hip replacement. The preoperative radiographs were templated, calibrated holders for the cement restrictors were used intraoperatively, keeping the distal cement height within 2-3 cm from the tip of the femoral prosthesis. Postoperative radiographs were analysed. The Harris Hip scoring system was used for clinical assessment of results. The preoperative target of having a distal cement height of 2-3 cm was achieved in only 60.6% of the bone block group and 30.6% of the Hardinge group. The difference between the two groups is statistically significant (p = 0.001). Distal migration of the restrictors more than 3 cm from the tip of the femoral prosthesis was associated with a non-homogenous cement mantle in zones 3, 4 and 5 without affecting zones 1, 2, 6 and 7. The cement mantle was adequate when the distal cement mantle remained within 2-3 cm of the tip of the femoral prosthesis.     

Technical considerations of cemented acetabular components: a 30-year evaluation

The effect of porosity reduction cementing techniques with respect to radiolucent lines in Zone 1 and failure in acetabular components was studied in 2,237 consecutive cemented acetabular components done between 1970 and 1998. The minimum followup was 2 years. Radiolucencies in Zone 1 on initial radiographs obtained postoperatively were tabulated for five groups of patients based on cementing techniques. The percentage of loose or revised cups was calculated for six groups based on type of prosthesis used. The lowest percentage of Zone 1 radiolucencies was in a group in which bowl mixing was used. The lowest failure rate was in the group that received Charnley prostheses in which simple first generation cement techniques were used. Porosity reduction techniques did not reduce the incidence of Zone 1 radiolucencies. For the acetabular side of a total hip replacement, the biology of the bone and the techniques of cement insertion that include a dry cancellous bone bed, perforation and removal of peripheral sclerotic areas, pressurization of the entire cement mantle in the socket at one time, and complete burying of the acetabular component within the boundary of the bony acetabulum are the essential factors, not porosity reduction in the cement.     

Assoziation zwischen Benzoylperoxidallergie, Vitiligo und Implantation einer zementierten Knieprothese

Allergies against bone cement or bone cement components have been well-described. We report on a 63-year-old patient who presented with progressive vitiligo all over the body after implantation of a cemented total knee replacement. A dermatological examination was performed and an allergy to benzoyl peroxide was found. A low-grade infection was diagnosed 5?months after implantation of the total knee replacement and the prosthesis was replaced with a cement spacer. After treating the infection of the knee replacement non-cemented arthrodesis of the knee was performed. In cases of new, unknown skin efflorescence, urticaria and periprosthetic loosening of cemented joint replacement, the differential diagnosis should include not only infections but also possible allergies against bone-cement and components such as benzoyl peroxide or metal components.     

Periprosthetic femoral fractures--a comparison between cemented and uncemented hemiarthroplasties

Over a 2-year period, 244 patients underwent hemiarthroplasty for a displaced intracapsular femoral neck fracture. Seventy patients had a cementless Austin-Moore prosthesis (AMP) inserted and 174 patients were treated using a cemented Thompson hemiarthroplasty. All the AMPs were inserted by or under the supervision of an orthopaedic consultant. Five patients (7%) from the AMP group sustained a periprosthetic femoral fracture. Two were iatrogenic and three occurred postoperatively after a simple fall. The fractures occurred proximally around the prosthesis (Johansson type I). Four required revision surgery. There were no periprosthetic femoral fractures in the Thompson group. When compared to the cemented Thompson hemiarthroplasties, the number of periprosthetic femoral fractures was significantly greater with the AMP. Patients in the AMP group were significantly older, although there was no significant difference in ASA grade between the two groups. There was no significant difference in age or gender between those who sustained a periprosthetic fracture and those who did not. These findings suggest that due to the increased risk of periprosthetic femoral fracture, cemented hemiarthroplasty is preferable. Furthermore, with modern cementing techniques, elderly frail patients appear to tolerate bone cement, which may serve to reinforce an osteoporotic proximal femur.     

The cemented kinematic-II and the non-cemented porous-coated anatomic prostheses for total knee replacement. A prospective evaluation

One hundred and sixty consecutive total knee arthroplasties were performed in 143 patients: 110 procedures, with a cemented kinematic-II prosthesis and fifty procedures, with a non-cemented porous-coated anatomic prosthesis. Each patient was evaluated before the operation and six weeks and three, six, twelve, and twenty-four months postoperatively. At a minimum twenty-four-month follow-up, the average Hospital for Special Surgery knee-rating score for the patients who had a cemented kinematic-II prosthesis was 9 points higher than the average score for the patients who had a non-cemented anatomic implant (88 points and 79 points). At the same follow-up period, the maximum flexion of the knees that had a cemented kinematic-II prosthesis was greater than that of the knees that had a non-cemented anatomic prosthesis (106 degrees and 97 degrees). In addition, the rate of reoperation for the patients who had a cemented kinematic-II replacement was 4 per cent, compared with 12 per cent for the patients who had a non-cemented anatomic prosthesis. On the basis of this prospective, non-randomized clinical review of unselected patients, we concluded that the results with the cemented kinematic-II prosthesis were superior to those with the non-cemented anatomic prosthesis at a minimum twenty-four month follow-up; however, these superior results may be related to the use of cement or to differences in the designs of the prostheses, the ages of the patients, or the postoperative management of the two groups of patients.     

Periprosthetic femoral fractures treated with a modular distally cemented stem

PURPOSE: To assess the treatment outcome of revision hip arthroplasty for Vancouver type B3 periprosthetic femoral fractures using a modular distally cemented stem. METHODS: 22 men and 14 women (37 hips) aged 66 to 79 (mean, 70) years underwent revision hip arthroplasty for Vancouver type B3 periprosthetic femoral fractures. The indication for surgery was periprosthetic fracture with stem loosening and loss of proximal bone stock. The patients were referred from other hospitals after previous surgeries had failed: 8 with 3 previous surgeries, 19 with 2, and 9 with one. Using a transtrochanteric approach, the existing prosthesis was removed and a modular proximal femoral replacement stem was inserted, bypassing the area of proximal femoral fracture and bone loss. The stem was distally cemented. Patients were immobilised within 48 hours of surgery. RESULTS: Patients were followed up for a mean of 14 (range, 8-18) years. The mean Harris hip score improved from 29 (range, 5-40) to 78 (range, 56-88); 24 patients attained excellent or good scores (>80), 10 attained fair, and 2 attained poor scores. The mean healing time was 7 (range, 6-14) months; there was no non-union. Improvement in proximal bone stock was noted on serial radiographs. None of the stems had cement fracture or migration, requiring revision. Two (5%) of the patients had dislocations. CONCLUSION: Vancouver type B3 periprosthetic femoral fractures can be successfully treated with a distally cemented modular proximal femoral replacement prosthesis.     

Lymphocyte response to polymethylmethacrylate in loose total hip prostheses.

We investigated the lymphocyte-mediated immune response to polymethylmethacrylate bone cement in 26 patients who had revision surgery for aseptic loosening of cemented total hip arthroplasties, at a mean time of seven years after the first replacement. We studied eight patients with cemented total hip arthroplasties which were not loose as controls. Patch tests to polymethylmethacrylate bone cement were positive in 13 patients with loosening, and these patients had higher lymphoblast transformation values against polymethylmethacrylate bone cement patients with a negative skin reaction (p < 0.01) or those in the control group (p < 0.001). Specific monoclonal antibodies were used to assess the percentage of certain cells of the immune system according to their cluster of differentiation (CD). There was a higher number of total T and B lymphocytes (CD2 and CD22) and interleukin-2 receptor-positive lymphocytes (activated cells, CD25) in patients with loose prostheses. More CD25 lymphocytes were found in patients with positive patch tests. The activation of the lymphocyte-mediated immune response was not related to the presence or absence of aggressive granulomatous lesions at the cement-bone interface.     

Bone cement and the liver. A dose-related effect?

The serum liver enzyme levels of 40 consecutive patients before and after cemented hip replacement were compared with a control group having operation without use of cement. Serum gammaglutamyl transferase (SGGT) was abnormally raised, for more than four days, in 12 of the 40 patients (32%) in whom bone cement was used, compared with one of the 36 control patients. The changes in SGGT levels after operation correlated with the weight of cement used (r = 0.66, p less than 0.001), but there was return to normal levels in all patients. A temporary dose-related effect of bone cement on liver function is demonstrated.     

Changes in bone density after cemented total knee arthroplasty: influence of stem design

Total knee arthroplasty has shown excellent survivorship in short-term and intermediate-term studies. With longer follow-up, however, aseptic loosening becomes an increasing cause of failure. Dual-energy x-ray absorptiometry scanning has shown that stress shielding occurs from altered mechanical loading. The purpose of this study is to determine if tibial stem design affects bone density in the longterm. Bone densities in the proximal tibia with and without cemented stems were compared at an average of 94 months after surgery. The bone quality under the Miller-Galante I prosthesis, which has 4 0.5-cm pegs, was compared with the bone quality under a Press-Fit Condylar prosthesis with a single 4-cm stem. Each group was also compared with the unoperated contralateral tibia. Results showed that there is a significantly reduced density of bone in the tibial metaphysis in the cemented stemmed group but not in the pegged group. There were no changes distally in the diaphyseal bone. This study supports the contention that the use of a cemented stem reduces proximal stresses and may result in proximal bone resorption. Although the use of a stem provides excellent resistance to lift-off and shear, it comes at a price. The proximal resorption may contribute to the persistence of tibial component loosening as a primary threat to survivorship. This bone loss may complicate revision surgery. Consideration should be given to using shorter tibial stems, less cement, or alternative designs that avoid long-stem fixation.     

The effect of irrigating solutions on the strength of the cement-bone interface.

Irrigating solutions are commonly used in the preparation of bony surfaces before total joint replacement components are cemented. Using an experimental cemented arthroplasty model, metal pseudo-prostheses were cemented to a cadaveric bone surface prepared with a specific irrigating solution. A tension load was then applied to the prosthesis until failure occurred at the cement-bone interface. A quantitative analysis of the effect of three commonly used irrigating solutions on the strength of the cement-bone interface is presented. Sixty trials were performed with normal saline, povidone iodine and hydrogen peroxide. Irrigation with hydrogen peroxide afforded statistically superior cement fixation in this arthroplasty model when compared with either normal saline or povidone iodine (P less than 0.01 Chi-squared test).     

Does bone quality predict loosening of cemented total hip replacements?

We matched 78 patients with a loose cemented Charnley Elite Plus total hip replacement (THR) by age, gender, race, prosthesis and time from surgery with 49 patients with a well-fixed stable hip replacement, to determine if poor bone quality predisposes to loosening. Clinical, radiological, biomechanical and bone mineral density indicators of bone quality were assessed. Patients with loose replacements had more pain, were more likely to have presented with atrophic arthritis and to have a history of fragility fracture, narrower femoral cortices and lower peri-prosthetic or lumbar spine bone mineral density (all t-test, p < 0.01). They also tended to be smokers (chi-squared test, p = 0.08). Vitamin-D deficiency was common, but not significantly different between the two groups (t-test, p = 0.31) In this series of cemented hip replacements performed between 1994 and 1998, aseptic loosening was associated with poor bone quality. Patients with a THR should be screened for osteoporosis and have regular radiological surveillance.     

股骨假体周围骨密度定量测定

目的 通过双能X线骨密度仪测定不同情况下股骨假体周围的骨密度变化情况,了解骨丢失与股骨假体松动的关系。方法 分为骨水泥固定的股骨假体组、非骨水泥固定的股骨假体组、股骨假体松动组共3个组,采用LUNAR DPXL-L型双能X线骨密度仅(Lunar Corp Wisconsin,USA)及Orthopaedies软件,分析时用Gruen’s 7区法。结果 骨水泥固定的股骨假体组骨丢失为15．1%～29．3%,非骨水泥固定的股骨假体组骨丢失为13．2％～27．9%,股骨假体松动组骨丢失为25．4％～43．4%,3组均是股骨近端骨丢失明显．骨丢失主要发生在术后8年以内。结论 骨水泥固定的股骨假体和非骨水泥固定的股骨假体周周骨密度降低一样,假体松动者假体周围骨丢失明显增加。股骨近端2个以上区域骨丢失大于35％或术后8年以后突然出现明显的骨丢失,考虑有股骨假体松动存在的可能性。     

Safeness of Simplex-tobramycin bone cement in patients with renal dysfunction undergoing total hip replacement

PURPOSE: To compare the pharmacokinetic profile of tobramycin in blood, urine, and at the operative site following the use of Simplex-tobramycin bone cement in primary total hip replacement between patients with and without renal dysfunction. METHODS: Six patients with renal dysfunction underwent cemented primary total hip replacement for osteoarthritis. The elution characteristics of Simplex-tobramycin bone cement in the 6 patients with renal dysfunction were compared with 9 patients who had normal renal function. Blood, urine, and drainage fluid specimens were collected for 72 hours postoperatively. RESULTS: Very high concentrations of tobramycin were seen in the drainage fluid of the 2 groups. Mean serum tobramycin levels peaked at postoperative 3 hours, and declined rapidly to negligible levels at 72 hours in both groups. Mean urinary tobramycin concentrations peaked at postoperative 12 hours and declined rapidly until 48 hours in both groups. Urinary tobramycin was excreted significantly more slowly in renal dysfunction group in the first 12 hours, but not thereafter. Although serum creatinine levels of the renal dysfunction group were higher throughout the study period, the difference was not significant. Both groups achieved excellent local delivery of the antibiotic with minimal systemic concentrations. CONCLUSION: Simplex-tobramycin bone cement appears to be an effective and safe means to deliver antibiotic for patients with renal dysfunction who undergo total hip replacement.     

Total hip replacement with cemented, uncemented, and hybrid prostheses. A comparison of clinical and radiographic results at two to four years

One hundred and thirty-one patients who had 144 cemented or uncemented hip prostheses were followed prospectively for two to four years. A cemented or a hybrid prosthesis (consisting of a cemented femoral component and an uncemented acetabular component) was used in men older than seventy years, in women older than sixty years, and in younger patients in whom adequate initial fixation could not be obtained without cement. Uncemented, porous-surfaced implants were used in all other patients. The over-all clinical results were similar for the three groups. For the fifty-two hips that had a cemented prosthesis, the mean total Harris hip rating was 91 points and the score for pain, 42 points; for the twenty-seven hips that had a hybrid prosthesis, 90 and 43 points; and for the sixty-five hips that had an implant allowing ingrowth of bone in both the acetabulum and the femur, 95 and 43 points. Two prosthetic stems that were designed to allow ingrowth of bone had aseptic loosening; one was revised. Pain in the thigh, usually slight and not disabling, occurred at one year in 24 per cent of the patients in whom a femoral component allowing ingrowth had been used; the prevalence of pain then declined. The incidences of migration of the components and of radiolucent lines were greater in the acetabula that had a cemented component than in those that had a cup allowing ingrowth of bone.     

Failure of total hip arthroplasty with Boneloc bone cement

Early failure of Boneloc cemented total hip arthroplasty is well documented. However, information regarding the long term prognosis is scanty. The aim of this study was therefore to assess the long term failure rate of total hip replacement with Boneloc bone cement. Between January 1991 and March 1992, Boneloc bone cement (Polymers Recontructive A/S, Farum, Denmark) was used in 42 consecutive total hip replacements in 42 patients. The average age of the patients was 75 years. There were 25 women and 17 men. The diagnosis at operation was osteoarthritis in all cases. A cemented Muller Taperloc femoral stem was used with a cemented Muller acetabular cup (Biomet, Warsaw, USA). The follow-up time was 9 years. All patients underwent radiographic control the first postoperative year and annually after 1995. To date 21 patients have been revised for aseptic loosening at a mean of 5 years (range: one year to 8 years). Three other patients have definite radiographic evidence of loosening. The overall failure rate is therefore 24/42 = 57%. Our results confirm the previously reported poor results of Boneloc bone cement for hip arthroplasty and support the recommendation of indefinite follow-up for surviving prostheses. New prosthesis designs and new cements should have documentation, including laboratory tests and randomized clinical studies with radiostereometric evaluation. However, the ethical responsibility rests heavily on the shoulders of the clinician to make a correct analysis of the need for a new product before he begins to use it.     

骨水泥型与非骨水泥型人工半髋关节置换术治疗高龄股骨颈骨折患者的对比研究

目的对比骨水泥型与非骨水泥非骨水泥型人工半髋关节置换术在高龄股骨颈骨折患者中的治疗效果。 方法前瞻性收集2014年1月至2018年12月期间行唐县人民医院收治的112例高龄股骨颈骨折患者为研究对象，采用随机数字表法将患者分为骨水泥组、非骨水泥组，每组各56例。骨水泥组患者给予骨水泥型人工半髋置换手术治疗，男26例，女30例，年龄（72±4）岁。非骨水泥组给予非骨水泥人工半髋关节置换术治疗，男31例，女25例，年龄（73±4）岁。对比两组患者围术期相关指标、手术效果、并发症发生率，并对两组患者术后进行为期3年的随访观察，对患者在随访期间的Harris髋关节功能评分、不良事件发生率等进行统计对比。 结果112例患者获得完整随访，随访时间（36±5）个月。两组患者手术时间、术中失血量、引流量等差异无统计学意义（P>0.05），而骨水泥组患者的住院时间[（14±3）d]、开始负重时间[（41±9）d]均低于非骨水泥组[（17±3）d、（46±10）d]（t=4.353，2.856，P<0.05）。骨水泥组手术优良率为87.50%（49/56），高于非骨水泥组71.43%（40/56）（χ²=4.432，P<0.05）。骨水泥组术后并发症发生率为7.14%（4/56），低于非骨水泥组的21.43%（12/56）（χ²=4.667，P<0.05）。骨水泥组患者的Harris评分在术后6个月[（82±14）分]、12个月[（86±8）分]、24个月[（91±7）分]、36个月[（95±4）分]均优于非骨水泥组[（76±11、81±9、87±8、91±6）分]。骨水泥组不良事件发生率为8.93%（5/56），低于非骨水泥组的23.21%（13/56）（χ²=4.236，P<0.05）。 结论相较于非骨水泥型人工半髋关节，骨水泥型人工半髋关节置换术对于高龄股骨颈骨折患者的手术效果更好，术后关节功能恢复好，值得临床推荐。     

THE EFFECT OF IRRIGATING SOLUTIONS ON THE STRENGTH OF THE CEMENT-BONE INTERFACE

Irrigating solutions are commonly used in the preparation of bony surfaces before total joint replacement components are cemented. Using an experimental cemented arthroplasty model, metal pseudoprostheses were cemented to a cadaveric bone surface prepared with a specific irrigating solution. A tension load was then applied to the prosthesis until failure occurred at the cement-bone interface. A quantitative analysis of the effect of three commonly used irrigating solutions on the strength of the cement-bone interface is presented. Sixty trials were performed with normal saline, povidone iodine and hydrogen peroxide. Irrigation with hydrogen peroxide afforded statistically superior cement fixation in this arthroplasty model when compared with either normal saline or povidone iodine (P < 0.01 Chi-squared test).     

Difficult implant retrieval: a case report

Artificial joint prostheses can be expected to fail eventually. The author describes the case of a woman whose cemented knee-joint hinge prosthesis failed and required revision. This prosthesis was designed so that the stem became thinner as it approached the bearing surfaces. As a result the implant could not be removed from the cement and the cement could not be removed without severe destruction of surrounding bone. Although this prosthesis is no longer being used, there may be patients having this implant who will require revision in the future. This paper warns surgeons that its removal will be extremely difficult and appropriate plans should be made preoperatively. The author concludes that no stemmed implant should be cemented in place if it cannot readily be removed from the cement.