Proximal cement fixation in total hip arthroplasty—first results with a new stem design

Stem loosening and stress-shielding are problems encountered in cemented hip arthroplasty. Could proximal stem fixation by partial cementing solve the problem? More physiological transmission of forces with only proximal cement fixation seems to be possible with this recent development (Z-stem, Option 3000, Mathys Orthopaedics, Bettlach, Switzerland). In a prospective clinical trial, this new implant was used for total hip arthroplasty in human patients. One hundred and thirty-three (133) total hip replacements in 123 patients were performed between April 1996 and January 2003. All of them were followed up regularly; 53 were analysed with the EBRA-FCA method (Einzel Bild Röntgen Analyse—femoral component analysis), whereas the rest were analysed using conventional follow-up X-rays. Eighty-six (86) patients with 95 hips could be examined in August 2004 to obtain mid-term results. At this stage, the mean follow-up time was 61 months (5.08 years), with a maximum of 100 months (8.33 years). Up to October 2004, nine cases needed a revision. The clinical data collected reported an average Harris Hip Score of 89.3 (good). The EBRA-FCA analysis reported a mean subsidence of less than 1.5 mm after the first two years, under the EBRA threshold of predicted loosening. At the latest follow-up (at an average of 61 months), there was an average stable subsidence of 2.4 mm in general. Eight (8) patients presented with subsidence of more than 5 mm. The results of the new implant seem to be encouraging. Finally, comparing our results to other fixation concepts will require longer follow-up periods.     

No increased stem subsidence after arthroplasty in young patients with femoral head osteonecrosis: 41 patients followed for 1-9 years

BACKGROUND: Poor bone stock in patients with osteonecrosis of the femoral head may be a reason for poor outcome after hip replacement. One way of studying bone quality is to measure implant migration. We thus investigated the clinical and radiographic results of cementless THR in younger patients with femoral head osteonecrosis. PATIENTS AND METHODS: We studied hips in 41 patients (mean age 48 (25-63) years) with a cementless hip arthroplasty after late stage osteonecrosis. Clinical evaluation was by the Harris hip score, the WOMAC score and the SF-36 score. Stem subsidence was measured with the Ein Bild Roentgen Analyse femoral component analysis (EBRA-FCA) at 3, 12, 24, 60, and 72 months after operation. The average duration of follow-up was 7(1-9) years, with less than 2 years for 2 patients. RESULTS: There was no revision of any hip. No radiographic or clinical stem loosening was seen. After 60 months, the cementless stems showed a median subsidence of -0.7 mm (95% CI: -0.9 to -0.2). No femoral osteolysis occurred. Femoral radiolucent lines, all < 1 mm, were seen in 10 hips. At the latest follow-up the Harris hip score was 83 (23-100) points. INTERPRETATION: Our findings for porous-coated stems in patients with femoral osteonecrosis indicate no greater risk of stem subsidence and rate of osteolysis after an average of 7 years follow-up. Thus, we continue to use uncemented stems in younger patients with femoral osteonecrosis. However, continued follow-up will be necessary to evaluate the long-term outcome.     

No increased stem subsidence after arthroplasty in young patients with femoral head osteonecrosis:41 patients followed for 1–9 years

Background?Poor bone stock in patients with osteonecrosis of the femoral head may be a reason for poor outcome after hip replacement. One way of studying bone quality is to measure implant migration. We thus investigated the clinical and radiographic results of cementless THR in younger patients with femoral head osteonecrosis.

Patients and methods?We studied hips in 41 patients (mean age 48 (25–63) years) with a cementless hip arthroplasty after late stage osteonecrosis. Clinical evaluation was by the Harris hip score, the WOMAC score and the SF-36 score. Stem subsidence was measured with the Ein Bild Roentgen Analyse femoral component analysis (EBRA-FCA) at 3, 12, 24, 60, and 72 months after operation. The average duration of follow-up was 7(1–9) years, with less than 2 years for 2 patients.

Results?There was no revision of any hip. No radiographic or clinical stem loosening was seen. After 60 months, the cementless stems showed a median subsidence of –0.7?mm (95% CI: –0.9 to –0.2). No femoral osteolysis occurred. Femoral radiolucent lines, all < 1?mm, were seen in 10 hips. At the latest follow-up the Harris hip score was 83 (23–100) points.

Interpretation?Our findings for porous-coated stems in patients with femoral osteonecrosis indicate no greater risk of stem subsidence and rate of osteolysis after an average of 7 years follow-up. Thus, we continue to use uncemented stems in younger patients with femoral osteonecrosis. However, continued follow-up will be necessary to evaluate the long-term outcome.     

股骨大转子延长截骨在假体稳定股骨柄翻修中的应用

目的 评估大转子延长截骨在股骨假体固定稳定型全髋关节翻修术中应用的中期临床效果.方法 1998年1月至2005年6月对27例患者(27髋)采用大转子延长截骨对股骨柄和(或)骨水泥壳固定稳定的全髋关节翻修.临床随访评估包括Harris评分和WOMAC评分,术前Harris评分平均42.7分,WOMAC评分平均55.6分;影像学评估包括术后拍摄X线片,对比观察截骨块愈合时间、是否存在截骨延迟愈合或不愈合,截骨块是否发生移位以及假体是否下沉等.结果 共19例患者(19髋)获得随访,平均随访时间5.3年.无一例发生术中或术后骨折.术后Harris评分平均87.3分,WOMAC评分平均46.3分.所有患者大转子截骨块均于术后6个月内愈合.无股骨大转子截骨块向近端移位,3例发生股骨柄下沉,平均下沉3.4 mm,无钢丝断裂.结论 对于假体固定稳定型股骨柄翻修,采用股骨大转子延长截骨有利于手术操作和翻修假体的植入和固定,有利于截骨块的愈合,降低术中、术后并发症发生率,中期疗效显著.     

Design and first clinical results with the ZMR taper revision prosthesis

AIM: The purpose of this study was to survey and to evaluate the first clinical and radiological results with the cementless ZMR taper hip prosthesis. METHOD: The modular distal-tapered stem was designed with a roughened titanium surface and sharp splines to achieve secure distal fixation and rotational stability. 90 ZMR taper hip prostheses were implanted between October 1999 and July 2002. Out of these, 4 interventions were primary and 86 were revision procedures. In 43 cases a complete hip prosthesis revision and in 43 cases a stem revision was necessary. The mean age of the 90 patients (42 males, 48 females) was 67.1 years. The mean follow-up period was 7.6 months (3 to 25 months). RESULTS: The stem displayed an excellent distal fixation. The mean subsidence could be measured with 4.3 mm. Furthermore, most cases showed a particularly favourable remodelling of the proximal femoral bone stock. Complications associated with revision included intraoperatively 4 femur fractures, 3 femur fissures, 5 femur perforations, 2 trochanter fractures and postoperatively 19 dislocations, 5 superficial wound infections, 2 transient palsies, 1 pulmonary embolism, 1 stem rotation and 4 wound healing failures. Considering these complications 15 re-revisions were necessary and the ZMR taper hip prosthesis had to be exchanged in 3 cases. CONCLUSION: On the one hand the ZMR taper hip prosthesis proved its value, particularly with regard to the stem modularity, the excellent distal fixation in conjunction with the possibility of partial body weight bearing and the rapid bone remodelling of the femur. On the other hand an increased number of postoperative complications and re-revisions occurred. Further long-term studies seem to be essential.     

Long-term results with the BiCONTACT system--aspects to investigate and to learn from

The BiCONTACT femoral stem for cementless fixation is being used without any technical modification after 15 years. The long-term results should be evaluated in this study. A consecutive series was continuously monitored in a prospective follow-up study. A survival analysis was performed, clinical results were rated according to the Harris score. There were 236 patients with 250 total hip replacements (THR); mean age at time of implantation was 58.2 years. Indications for THR included osteoarthritis (62.4%), dysplasia (16.8%), trauma (8.4%) and femoral-head necrosis (16.8%). Average time of follow-up evaluation was 8.9 years (range 7.4-10.7 years). At follow-up, 27 patients had died and two could not be located. Seven patients were revised--two for infection, one for recurrent dislocation, two for component undersizing with rapid subsidence, and one for aseptic loosening of a varus-malaligned stem; one radiologically well-fixed stem had been revised during acetabular revision. Survival estimate showed an overall survival rate of 97.1% after 11 years (confidence limits: 98.7% upper and 93.6% lower). Radiologically, tiny reactive lines (< 2 mm) were present in the distal zones of the femoral shaft, but no radiolucencies could be found in the proximal anchoring zone. Migration analysis with Ein-Bild-R?ntgen-analyse/femoral component analysis (EBRA/FCA) demonstrated a very small amount of migration: in 31.0%, the overall migration was between 0.5 and 1 mm after 120 months; 8.5% had an absolute amount of subsidence exceeding 2 mm after 120 months (one case more than 3 mm). Mean subsidence was 0.2 mm after 3 months and 6 months, 0.3 mm after 12 months, and reached 0.5 mm after 10 years. An initial small amount of subsidence could be detected in 45.1%, and 15.5% had a late onset of subsidence. Continuous sinking could be found in 12.7%, while 26.8% had irregular patterns of migration. Clinical results were somewhat compromised by a higher-than-average rate of cup loosening (uncoated threaded cup). The average Harris hip score at follow-up was 84.3 points. Interestingly, no femoral osteolysis could be detected, even in cases with severe acetabular osteolyses, indicating sealing of the stem interface by tight osseointegration of the proximally-coated stem.     

Assessment of early migration and clinical evaluation of a cemented femoral stem

A 2-year follow-up study was conducted on 46 patients to assess Harris Hip Scores (HHS) and early distal migration of the femoral stem after total hip arthroplasty using a fully cemented femoral stem. The mean age was 73.4 years. The Fullfix stem (Mathys A.G., Bettlach, Switzerland) is characterised by a mat polished surface and a flange aimed to compress the cement during the insertion process. Early distal migration was determined in 36 patients using the computer assisted EBRA-FCA method (Einzel-Bild-Roentgen-Analyse femoral component analysis). At 2 years, subsidence reached a mean value of 0.44 mm (95% CI: 0.19, 0.70), whereafter the stem appeared stable, i.e. distal migration reached a plateau. Females showed significantly higher migration than males (p < 0.01). EBRA-FCA proved to be an accurate method to measure early migration, with a standard deviation below 1 mm (0.56 mm in the interval 1-2 years). Harris Hip Scores (HHS) at 2 years follow-up averaged 89.6 (95% CI: 79.5, 99.8). As expected considering the small extent of migration, there was no correlation between subsidence and HHS (p = 0.5).     

Correlation between thigh pain and radiological findings with a proximally porous-coated stem

Thigh pain has been consistently reported with cementless hip arthroplasty. The correlation between thigh pain and radiological findings and the clinical significance of thigh pain have not been studied in any detail. We carried out a retrospective study to analyse the performance of a proximally porous-coated cementless femoral component. Ninety-eight total hip arthroplasties were followed up clinically and radiologically for an average of 33 months (range: 12 to 64) after operation. The clinical results were good or excellent in 85 cases (87%). Thirteen patients (13%) reported thigh pain at latest follow-up. Subsidence of the stem was recorded in 10 cases, cortical thickening occurred in 14 hips (14%), and 17 hips (17%) presented proximal osteopenia. Proximally, radiolucent lines were observed in 11 cases. Thigh pain correlated with radiolucent lines, femoral thickening, fibrous fixation and stem migration. Bone remodelling was noted to continue even five years after implantation. Our observations demonstrated bone ingrowth in the majority of the cases and a low incidence of thigh pain. The correlation between radiological changes and thigh pain suggests implant micromotion and migration in some hips. Patients with thigh pain, changes in the proximal femur and progressive subsidence need further clinical and radiological follow-up.     

非骨水泥长柄假体结合同种异体颗粒骨植骨在股骨翻修骨缺损重建中的应用

目的 回顾性分析股骨髓内同种异体颗粒骨打压植骨结合非骨水泥长柄假体在髋关节翻修术中股骨侧骨缺损修复应用的近期临床效果.方法 2003年7月至2009年6月对27例股骨侧骨缺损患者采用同种异体颗粒骨打压植骨,其中男性15例,女性12例,年龄47～78岁,平均67岁.失败原因:骨溶解、无菌性松动20例,全髋关节置换术后假体周围感染二期翻修7例.按Paprosky分型标准,Ⅱ型骨缺损3例,Ⅲ型骨缺损2l例,Ⅳ型骨缺损3例.术中均采用同种异体颗粒骨打压植骨、非骨水泥翻修柄植入.定期随访复查,包括临床、影像学评估,观察假体有无松动、下沉,植入骨活化替代情况以及假体周围骨折等并发症.Harris评分术前平均43分(37～62分).结果 23例患者获得随访,随访时间3～47个月,平均26.4个月.术后末次随访时.Harris评分平均83分(67～97分).术中2例发生股骨大转子骨折,无一例发生术后假体周围骨折等并发症.1例术后发生关节脱位,1例发生深静脉血栓,1例术后2周发生急性感染,经扩创、置管冲洗、抗感染治疗成功保留假体;发生异位骨化1例,Brooker Ⅰ级.影像学所有患者股骨柄中置,无内翻或外翻,随访期内无一例发生股骨柄移位(内翻或外翻角度变化>3°).23例患者显示至少Ⅰ区股骨髓内移植骨与周围骨或与股骨柄整合.4例发生股骨柄假体下沉,平均下沉3.3 mm(2～6 mm).结论 股骨侧翻修中,良好的股骨髓内同种异体颗粒骨打压植骨结合合适的非骨水泥延长柄股骨假体,可以修复关节置换术后各种原因所导致股骨骨缺损、重建股骨完整性,具有很好的近期临床疗效.但中远期临床效果尚待进一步观察.     

Langzeitergebnisse mit dem zementfreien CLS-Schaft von Spotorno

This retrospective study reviews 298 sequential cementless CLS Spotorno stems, which achieved their primary fixation and bony in- or ongrowth predominantly in the metaphyseal region. The minimum follow-up was 10 years and the average follow-up 11.7 years (range 10-14). The mean age at surgery was 55.2 years (range 32.2-68.9). Of the patients, 76.2% (227 stems) were followed up: 172 patients (57.7%) underwent clinical and radiological examination and 52 patients (55 stems, 18.5%) were interviewed by telephone. Of 298 stems, 13 (4.4%) had been replaced in the mean time, only 6 stems (2.0%) because of an aseptic loosening. The evaluation included both clinical (Merle d'Aubigne and Harris hip score) and radiographic parameters (plain X-rays). The mean Merle d'Aubigne score was 16.7 points, and the mean Harris hip score was 94.3 points. Radiolucent lines were detected in 33.7%; 5.8% showed enlargement within the last 3 years. Focal osteolyses were present in 30.8% of patients; 2.9% had progressed within the last 3 years. At follow-up, one patient presented with new clinical and radiological evidence of aseptic stem loosening. The current study showed an aseptic loosening of the CLS stem in 2.3%, a good osseointegration and good functional score results in more than 90%. The primary fixation and bony in- or ongrowth predominantly in the metaphyseal region seems to achieve good clinical results. Wear is the main reason for the osteolytic changes. Frequent clinical and radiological follow-up is important to detect bone reactions and loosening of the stem.     

Promising mid-term results of total hip arthroplasties using an uncemented lateral-flare hip prosthesis: a clinical and radiographic study

The clinical results after total hip replacements using noncemented stems have shown considerable variability over the years; the design and characteristics of the implant seemed to play a role in explaining this fact. The purpose of this paper is to report the clinical, radiographic and densitometry results of total hip arthroplasties using a stem designed for noncemented implantation and to engage and load the femur proximally. Fifty-eight consecutive patients (62 hips) followed for an average of 4.3 years (range 36-70 months) were clinically and radiographically followed up at three weeks, three months, six months, one year, and yearly thereafter. The average pre-operative Harris hip score was 49 increasing to 98 at the latest follow-up. There were no cases of aseptic or septic loosening. The average subsidence at three years was 0.45 mm (SD +/- 0.36 mm). Radiographically all hips were classified as stable, and evident changes compatible with new bone apposition were observed in 64% of the cases. The extended proximal geometry of the device seems to favour initial and secondary stability as reflected by the low subsidence values over time. The maintenance of periprosthetic bone stock and the absence of stress shielding can be explained by the predominantly proximal loading pattern of the stem.     

Total hip arthroplasty with a collarless, tapered, fiber metal proximally coated femoral stem: minimum 5-year follow-up

The purpose of this study was to evaluate the midterm results, osteointegration potential, and implant-related complications of a cementless, collarless, proximally coated, distally tapered femoral hip prosthesis. The clinical and radiographic results for 129 hips in 116 patients after total hip arthroplasty with a Fiber Metal Taper (Zimmer, Inc ,Warsaw, Ind) femoral stem are reported. One hundred twenty-two (95%) hips were available for the minimum of 5 years clinical and radiographic follow-up. The mean duration of follow-up was 81 months (range, 60-104 months). The mean Harris hip score improved from 44 to 92 at the most recent follow-up. All femoral components were clinically stable with radiographic evidence of bone ingrowth. There has been no evidence of subsidence greater than 2 mm, no significant thigh pain, and no femoral revisions for any reason. Total hip arthroplasty with the Fiber Metal Taper stem demonstrates good clinical and radiographic results at midterm follow-up.     

非骨水泥长柄假体在髋关节翻修术中的应用

目的回顾性分析非骨水泥全涂层长柄假体在全髋关节翻修术中应用的临床疗效。方法对2006年1月至2011年1月四川大学华西医院收治的采用全涂层长柄假体全髋关节翻修术的53例患者（53髋）进行随访、分析。其中男26例,女27例;年龄49—78岁,平均62岁。股骨假体采用强生（Depuy）公司全涂层长度为165mm的直柄AML假体10例、全涂层165mm的Solution假体19例和203mm带弧度分左右侧的Solution假体24例。比较髋关节术前术后的Harris评分,x线片评价假体柄有无松动下沉及应力遮挡情况。结果53例患者均获随访,随访时间1．8～6．8年,平均4．7年。术前平均Harris评分为37分,最后随访时增加至86分。所有患者均在术后3个月后完全负重,原有髋关节疼痛缓解。在最后随访时,有45例股骨柄假体获得骨长人固定。并发症：术后脱位1例,手法复位后未再发生脱位,术后感染1例,假体柄明显下沉1例,后两例患者行再次翻修术,末次随访假体柄稳定。随访X线片显示多数患者骨质改建,密度增加,未发现假体周围有连续亮带及假体柄下沉的患者。结论复杂的股骨侧翻修手术,应尽可能选择非骨水泥长柄假体。特别是股骨干骺端骨质条件差,中段有骨缺损,近端不能获得牢固固定的病例。术中结合同种异体颗粒骨打压植骨处理股骨中上段中重度骨缺损,中期临床疗效良好,远期效果有待随访。     

Outcome after femoral revision using the restoration cone/conical femoral revision stem

Despite improvements in implant technology and surgical technique, failure of total hip arthroplasty (THA) remains a persistent problem. This article reports clinical outcomes at a mean follow-up of 42 months using the Restoration cone/conical modular femoral revision stem (Stryker, Newbury, United Kingdom). A prospective cohort study was performed of 46 consecutive patients who underwent revision THA between January 2004 and June 2007. Patients were reviewed pre- and postoperatively at regular intervals for clinical and radiological assessment. Forty-six patients (17 men, 29 women) with a mean age of 72 years (range, 44-93 years) were observed for a mean of 42 months (range, 28-66 months). Indications for surgery included aseptic loosening/osteolysis (38/46 [83%]), periprosthetic fracture (4/46 [9%]), and infection (4/46 [8%]). Median time from index procedure was 16 years (range, 1-26 years). No patient was lost to follow-up. Two patients (4%) with well-fixed asymptomatic stems died during follow-up. Three patients (7%) sustained an early postoperative dislocation. One patient sustained a periprosthetic fracture after a fall. This was treated by osteosynthesis, and stem revision was not required. Mean Oxford Hip Score improved from 42 points (range, 24-57 points) to 28 points (range, 18-51 points) at 3-month follow-up (P=.003). Median stem subsidence was 1.0 mm (standard error of the mean, ±1.7 mm; range, 0-7mm) at last follow-up. No patient developed loosening or osteolysis around the stem. The Restoration femoral revision system has favorable clinical and radiological outcomes at a mean follow-up of 42 months.     

髓内打压植骨结合广泛多孔涂层长柄假体在股骨侧严重骨缺损（PaproskymA型）翻修术中的应用

目的 探讨股骨侧严重骨缺损（Paprosky ⅢA型）翻修中应用髓内打压植骨结合广泛多孔涂层长柄假体的临床疗效.方法 2006年3月～2010年9月,对38例（38髋）Paprosky ⅢA型股骨骨缺损患者行翻修重建,其中男24例,女14例,平均年龄62岁.翻修原因：骨溶解、无菌性松动29例,全髋关节置换术（THA）术后感染二期翻修6例,假体周围骨折3例（Vancouver B3型）.股骨侧干骺端骨缺损采用同种异体颗粒骨髓腔内打压植骨进行修复,股骨柄采用全涂层长柄假体（7～10英寸）.术后定期随访,髋关节功能评价采用Harris评分,影像学采用X线片及CT观察：假体柄有无松动下沉、股骨近端应力遮挡情况、植入的异体颗粒骨与宿主骨整合情况.结果 38例均获得随访,平均随访53.4个月（23～62个月）,Harris评分由术前平均42分（32～47分）,提高至末次随访时平均86分（69～95分）.无患者发生脱位、假体周围骨折.1例术后感染,行再次二期翻修;1例假体柄在术后6个月内下沉4.24 cm,再次翻修时选择更粗的假体柄,末次随访时假体柄稳定;其余所有患者假体柄均牢固固定.3例出现轻-中度应力遮挡.15例近端皮质骨密度及厚度有增加,厚度平均增加约1.8 mm（0.7～3.5 mm）,植入骨与宿主骨逐渐整合并增加了骨缺损区的骨质储备.结论严重骨缺损（Paprosky ⅢA型）的股骨翻修中,采用髓内颗粒骨打压植骨可以很好的修复股骨中上段骨缺损,重建股骨干骺端.依靠广泛多孔涂层长柄假体在远端的牢固压配固定,结合股骨干骺端髓内紧密打压植骨,使假体柄在股骨中上段及远端均能获得较好的初始稳定性,近期临床和影像学结果满意,远期疗效有待观察.     

Comparison of hydroxyapatite-coated and non-hydroxyapatite-coated noncemented total hip arthroplasty in same patients

The comparison between standard blasted and hydroxyapatite (HA)-coated cementless femoral stems (CLS stem) was made in the same patients who have bilateral late-stage osteonecrosis. Clinical and radiographic evaluations were performed in 20 patients (among 29 patients) with the minimum follow-up of 10 years (range, 123-168 months). Endosteal bone formation was found in all patients of both stems, and no radiolucent line was observed. The mean of initial stem subsidence was 1.27 +/- 0.95 mm with the standard stem and 0.59 +/- 0.56 mm with the HA-coated stem. Other results, such as hip score, endosteal bone formation, cortical hypertrophy, osteolysis, and heterotopic ossification showed no statistical differences. These have suggested that the fixation obtained by the cementless stem with a corundum-blasted surface is stable enough to get excellent clinical and radiographic results without the HA coating.     

生物型组配式锥形柄行全髋关节翻修术的中远期疗效

目的探讨应用生物型组配式锥形柄行全髋关节翻修术的中、远期疗效。 方法收集苏州大学附属第一医院2000年5月至2011年5月因假体无菌性松动、股骨侧骨缺损而采用生物型组配式锥形柄行全髋关节翻修手术的患者,排除肿瘤、假体感染及随访时间<5年的患者,共收录37例(39髋),其中采用利马股骨翻修柄19例(21髋),林克(LINK)MP翻修柄18例(18髋)。初次置换至翻修时间为4～15年,平均(10±4)年,均为首次翻修。股骨侧骨缺损分型按Paprosky标准：Ⅲa型28髋,Ⅲb型11髋。摩擦界面均使用陶瓷－陶瓷界面。Harris评分比较采用t检验,骨缺损程度分型组间差异采用卡方检验。 结果全部病例随访6～16年,其中11例随访6～10年,26例随访超过10年,平均(11.6±2.3)年。两种假体翻修时股骨缺损程度未见明显差异(χ²＝0.434; P>0.05)。术前平均Harris髋关节评分为(43±10)分,末次随访为(90±3)分(t＝32.334,P<0.05),两种翻修假体的临床疗效差异无统计学意义(t＝0.881,P>0.05)。X线随访显示翻修柄骨性稳定者38髋(97.4%),纤维稳定者1髋(2.6%)。假体平均下沉(2.1±2.3) mm(0～10 mm)。随访期间无1例因假体松动或其他原因需行再次翻修。 结论采用生物型组配式锥形柄假体行伴有Paprosky Ⅲa和Ⅲb型骨缺损的股骨侧假体翻修,可获得理想的初始稳定和永久生物学固定,中、远期随访疗效满意。     

The prediction of failure of the stem in THR by measurement of early migration using EBRA-FCA. Einzel-Bild-Roentgen-Analyse-femoral component analysis

We report the ten-year results for three designs of stem in 240 total hip replacements, for which subsidence had been measured on plain radiographs at regular intervals. Accurate migration patterns could be determined by the method of Einzel-Bild-Roentgen-Analyse-femoral component analysis (EBRA-FCA) for 158 hips (66%). Of these, 108 stems (68%) remained stable throughout, and five (3%) started to migrate after a median of 54 months. Initial migration of at least 1 mm was seen in 45 stems (29%) during the first two years, but these then became stable. We revised 17 stems for aseptic loosening, and 12 for other reasons. Revision for aseptic loosening could be predicted by EBRA-FCA with a sensitivity of 69%, a specificity of 80%, and an accuracy of 79% by the use of a threshold of subsidence of 1.5 mm during the first two years. Similar observations over a five-year period allowed the long-term outcome to be predicted with an accuracy of 91%. We discuss the importance of four different patterns of subsidence and confirm that the early measurement of migration by a reasonably accurate method can help to predict long-term outcome. Such methods should be used to evaluate new and modified designs of prosthesis.     

Femoral revision surgery with impaction bone grafting: 31 hips followed prospectively for ten to 15 years

The purpose of this prospective study was to evaluate the long-term clinical and radiological outcomes of revision of the femoral component of a total hip replacement using impaction bone grafting. Femoral revision with an impacted allograft was performed on 29 patients (31?hips). In all, 21 hips (68%) had grade III or IV femoral defects according to the Endo-Klinik classification. A total of 11 patients (12 hips) died before the ten-year follow-up period. Of the remaining patients, 18 patients (19 hips) were followed for 10 to 15 years; three further patients died during this time. None of the 31 stems underwent further revision of their stem. However, four stems showed extensive subsidence (> 15 mm). One of these patients had a femoral fracture that required fixation. Three other patients had a femoral fracture, two of which required fixation and the other was treated conservatively. Patients with a femoral fracture and/or severe subsidence had significantly more grade IV defects (six of seven hips; p = 0.004). One patient needed a closed reduction for dislocation. Impaction allografting in revision hip surgery gives good long-term results for femora with grades I, II and III Endo-Klinik-classified defects. Extensive subsidence and femoral fractures were seen mainly in patients with grade IV damaged femora.     

Survivorship and Radiological Analysis of a Monoblock,Hydroxyapatite-Coated Titanium Stem in Revision Hip Arthroplasty

BackgroundWe evaluated the survivorship, incidence of complications, radiological subsidence, proximal stress shielding, and patient-reported outcomes of a conservative, monoblock, hydroxyapatite-coated femoral stem.MethodsThis retrospective cohort study reports on 254 revision hip arthroplasties between January 2006 and June 2016. The mean age of patients was 71 years. The mean length of follow-up was 62 months (range 12-152).ResultsThere were 13 stem re-revisions: infection (4), periprosthetic fracture (4), aseptic stem loosening (3), stem fracture (1), and extended trochanteric osteotomy nonunion (1). Kaplan-Meier aseptic stem survivorship was 97.33% (confidence interval 94-100) at 6 years. There were 29 intraoperative fractures. There were 6 cases of subsidence greater than 10 mm; however, none required revision. Ninety-six percent of cases showed no proximal stress shielding. Thigh pain was reported in 3% of cases.ConclusionThis study confirms that this stem provides good survivorship at 6 years, acceptable complication rates, adequate proximal bone loading, low incidences of thigh pain, and reliable clinical performance in revision hip arthroplasty.Key MessageA monoblock, fully hydroxyapatite-coated titanium stem is reliable in revision arthroplasty with mild-moderate femur deficiencies.