Ganz reinforcement ring for reconstruction of acetabular defects in revision total hip arthroplasty

BACKGROUND: In revision total hip arthroplasty, bone loss due to loosening and migration of the acetabular component makes fixation of a new implant difficult. The purpose of this study was to evaluate the clinical and radiographic outcomes of the use of the Ganz reinforcement ring with nonstructural allograft in the reconstruction of acetabular defects. METHODS: Sixty-one acetabular revisions performed with use of the Ganz reinforcement ring and nonstructural allograft, between 1989 and 1992, in fifty-seven patients with aseptic loosening met our selection criteria. Eleven hips in eleven patients were lost to follow-up, leaving fifty hips available for evaluation five years or more following surgery. According to the American Academy of Orthopaedic Surgeons classification, twenty-four acetabular defects were Type II, twenty-four were Type III, and two were Type IV. Clinical and radiographic evaluations were carried out at a mean of six and nine years after surgery. Twelve more patients were lost to follow-up before the most recent evaluation. RESULTS: The mean Merle d'Aubigné composite score increased significantly compared with the preoperative score (p < 0.001). There were seven failures: six cases of aseptic loosening and one case of septic arthritis. Graft incorporation and bone remodeling occurred in all hips but three in which the ring fixation had been inadequate at the time of surgery. The Kaplan-Meier survivorship rate, with use of revision or loosening of the component as the criterion of failure, was 81% at ten years. Inadequate fixation of the implant at the time of surgery was the only multivariate predictor of failure (p = 0.003). CONCLUSIONS: Patients treated with acetabular revision with a Ganz reinforcement ring had reconstitution of periacetabular bone stock as well as good clinical and radiographic results, provided that the ring had been fixed adequately at the time of surgery. This procedure may not be the preferred approach for reconstructing segmental defects of the medial wall or pelvic discontinuity.     

Radiological evaluation of allograft reconstruction in acetabulum with Ganz reinforcement ring in revision total hip replacement

Background  

In revision total hip replacement (THR), cages and rings are commonly used for the reconstruction of bone defects that are due to mechanical loosening of the acetabular cup and migration of the femoral head prosthesis. The purpose of this study was to evaluate the radiological results of the use of Ganz reinforcement rings with bone allografts in acetabular revision THR.     

Pitfalls in the use of acetabular reinforcement rings in total hip revision

Introduction: For the reconstruction of acetabular bone defects different types of acetabular reinforcement rings are being used. In clinical practice, these implants showed to some extent good long-term results. In the present work pitfalls and complications after the implantation of acetabular reinforcement rings as well as possible solutions are being discussed. Material and methods: In the first case recurrent dislocation was caused by the malposition of the acetabular component with an impingement of the protruding bone cement and the anterior edge of the acetabular ring as well as muscle insufficiency as a result of the shortening of the leg length. The second case revealed an impingement of the iliopsoas tendon due to a protruding acetabular reinforcement ring. During revision, bone cement was used to smoothen the protruding anterior edge of the acetabular reconstruction ring in order to obtain a relieved sliding of the tendon. Furthermore, we report on the case of a delayed neuropathy of the sciatic nerve after reconstruction of the acetabulum with an acetabular reinforcement ring. Results: Intraoperatively an impingement of the sciatic nerve at the protruding dorsal edge of the acetabular reinforcement ring and the surrounding scar tissue was found. In a further case an aseptic loosening of an acetabular reinforcement ring caused the formation of an excessive granuloma with a large intrapelvic portion. The granuloma led to persisting senso-motoric deficits of the femoral nerve. In summary, based on these clinical cases possible pitfalls, associated with the use of acetabular reinforcement rings, are shown. The mal-positioning and the intra-operative re-shaping of the implant by the surgeon are pointed out as the substantial factors for the occurrence of an impingement phenomenon and total hip instability. Furthermore, in case of an adequate orientation of the cemented polyethylene insert an improper position of the acetabular ring which results in protruding edges has to be considered as a cause of a prosthetic impingement. Conclusion: The cases presented emphasize the necessity of prevention of such pitfalls intra-operatively as well as accurate analysis of implant failures. Furthermore, they suggest explicit preoperative planning before deciding on the strategy of revision surgery of acetabular reinforcement rings.No benefits or funds were received for this work.     

髋臼翻修过程中固定螺钉安全区的解剖学研究

目的 探讨评估髋臼翻修过程中假体同定螺钉的安全区域,测试四象限系统的有效性.方法 2006年12月至2008年1月,制备11例(22髋)正常国人冷冻骨盆髋标本,剔除肌肉组织后每例标本固定在仰卧位置,安装假体前后拍摄X线片,测量髋臼旋转中心的位置变化.右侧半髋用于评估超大(Jumbo)髋臼假体和高中心髋臼假体同定螺钉的安全区.左侧半髋用于评估3种重建加强环固定螺钉的安全区(臼内区和臼外区).结果 超大髋臼假体前上象限和前下象限发生了神经或血管损伤.高中心髋臼时除了后上象限后半部和后下象限以外其余象限均发生了神经或血管损伤.Müller重建环在前上象限(臼内12(和臼外区)发生了神经或血管损伤.Ganz重建环在前上象限(臼内区和臼外区)和臼顶区发生了神经或血管损伤,Butch-Schneider重建网笼在前上象限(臼内区和臼外区)和坐骨同定钉(当出骨长度大于15 mm时)发生了神经或血管损伤.结论 应用Jumbo非骨水泥假体和重建环时可以参照初次全髋关节置换时叙述的安全区.高中心髋臼手术时,我们常用的阴象限方法需要改进,前上象限及后上象限前部和臼顶区为不安全区域.     

Low Revision Rates at More Than 10 Years for Dual-Mobility Cups Cemented Into Cages in Complex Revision Total Hip Arthroplasty

BackgroundInstability and aseptic loosening are the two main complications after revision total hip arthroplasty (rTHA). Dual-mobility (DM) cups were shown to counteract implant instability during rTHA. To our knowledge, no study evaluated the 10-year outcomes of rTHA using DM cups, cemented into a metal reinforcement ring, in cases of severe acetabular bone loss. We hypothesized that using a DM cup cemented into a metal ring is a reliable technique for rTHA at 10 years, with few revisions for acetabular loosening and/or instability.MethodsThis is a retrospective study of 77 rTHA cases with severe acetabular bone loss (Paprosky ≥ 2C) treated exclusively with a DM cup (NOVAE STICK; Serf, Décines-Charpieu, France) cemented into a cage (Kerboull cross, Burch-Schneider, or ARM rings). Clinical scores and radiological assessments were performed preoperatively and at the last follow-up. The main endpoints were revision surgery for aseptic loosening or recurring dislocation.ResultsWith a mean follow-up of 10.7 years [2.1-16.2], 3 patients were reoperated because of aseptic acetabular loosening (3.9%) at 9.6 years [7-12]. Seven patients (9.45%) dislocated their hip implant, only 1 suffered from chronic instability (1.3%). Cup survivorship was 96.1% at 10 years. No sign of progressive radiolucent lines were found and bone graft integration was satisfactory for 91% of the patients.ConclusionThe use of a DM cup cemented into a metal ring during rTHA with complex acetabular bone loss was associated with low revision rates for either acetabular loosening or chronic instability at 10 years.     

Die Hakendachschale in der Revision schwieriger gelockerter Hüftprothesenpfannen

The long-term results of acetabular revision after total hip arthroplasty (THA) with the use of a reinforcement ring with hook were evaluated. The study included 57 cases of surgery dating back 10 years or more. Of a total of 54 patients (57 operated hips), 18 patients (19 hips) died during the 10-year period and 2 patients (2 hips) were completely lost to follow-up. At the time of the revision surgery, the mean age of the remaining 34 patients (36 hips) was 62.5 years (range: 47-80). A THA revision was done in 25 cases and an acetabular revision only in 11 cases. The most common acetabular defect was a combined segmental and cavitary defect (n = 19), and in three cases there was pelvic discontinuity. Autologous or homologous cancellous bone grafts were used to fill acetabular cavities in 17 hip joints. Structured bone grafts, predominantly homologous bone, were used in ten cases for acetabular reconstruction. At a mean follow-up of 11.4 years (range: 10-14.5) three hip joints (8%) had undergone further revision. The revisions were done for aseptic loosening of the acetabular component in two cases and a septic loosening of both components in one case. Three further cases (8%) revealed signs of acetabular loosening. Two of these three patients were symptomatic but refused further revision surgery. In the 33 unrevised hip joints, a good or excellent clinical result with a d'Aubingé score of more than 14 points was found in 30 cases (92%). Osseous acetabular reconstruction with the use of a reinforcement ring leads to favorable results compared to other techniques. In the authors' opinion, this technique is preferable to those using oversized cups without osseous reconstruction of the acetabulum.     

应用非骨水泥髋臼或金属髋臼支架行髋关节翻修术的临床研究

目的 评估非骨水泥髋臼及金属髋臼支架加植骨修复髋臼骨缺损的效果.方法 我院自2001年9月至2008年9月应用髋臼翻修支架行髋关节翻修术22例(24髋).其中Lima非骨水泥人工翻修髋臼2例(2髋),Kerboull 支架2例(2髋),GAP 髋臼翻修支架18例(20髋).男性6例(6髋),女性16例(18髋).平均年龄62岁(34～79岁).感染性松动2例(2髋),无菌松动20例(22髋).平均随访时间48个月(18～84个月),对其进行临床和影像学评估.Harris评分术前平均为56分(44～75分).结果 末次随访时22例患者Harris评分平均为89分(78～94分).优良率为95.5%(21/22).三种髋臼翻修支架的外展角满意,髋臼旋转中心基本得到了重建.髋臼翻修支架及其聚氯乙烯臼无明显移位,假体周围无透亮线,髋臼植骨愈合良好.结论 应用非骨水泥髋臼或髋臼支架修复髋臼侧巨大骨缺损,重建了髋臼正常旋转中心、提供了翻修假体的初期稳定性、避免了所植骨在血管化时期的过度机械负重,是翻修髋臼巨大骨缺损的可靠方法.     

髋臼加强环联合同种异体骨植骨重建髋臼在髋关节翻修中的应用

目的总结髋臼加强环(Cage)联合同种异体骨植骨重建髋臼在髋关节翻修术中的应用及疗效。方法 2006年2月-2010年8月,对14例(14髋)行人工全髋关节翻修术的重度髋臼骨缺损患者采用Cage联合同种异体骨植骨重建髋臼。男6例,女8例;年龄45～76岁,平均59.2岁。初次置换至此次翻修术时间为5～12年,平均7.2年。翻修原因:感染8例,骨溶解及假体松动6例。术前髋关节功能Harris评分为(37.7±5.3)分。髋臼骨缺损按照美国骨科医师协会(AAOS)分型标准:Ⅲ型8例,Ⅳ型6例。结果术后切口均Ⅰ期愈合,无坐骨神经损伤、下肢深静脉血栓形成等并发症发生。患者均获随访,随访时间14～62个月,平均44个月。患者疼痛症状均明显缓解或消失。末次随访时髋关节Harris评分为(89.7±3.2)分,与术前比较差异有统计学意义(t=—44.40,P=0.04)。X线片示髋臼假体均无松动,植骨未见明显吸收,并逐渐与宿主骨融合。结论在髋关节翻修时,采用Cage联合同种异体骨植骨能有效修复髋臼骨缺损并重建髋臼,近期疗效满意,远期疗效尚需进一步随访观察。     

Early complications after revision total hip arthroplasty with cemented dual-mobility socket and reinforcement ring

Encouraged by the success of dual-mobility sockets in achieving implant stability in primary hip replacement, surgeons have started to use the implant in revision hip arthroplasty. However, very little is known yet about the postoperative complication rate of this type of implant when fixation in a reinforcement ring is required. In our department, 37 dual-mobility sockets were cemented in a reinforcement ring for revision hip arthroplasty in 36 patients over a period of two years. The mean follow-up period was 16 months (range, 6-27 months). Indications for revision hip arthroplasty included, among others, recurrent dislocation (3 cases) and implant loosening (9 cases) with extensive bone loss. We observed two single re-dislocations (5.40%), one infection and one mechanical failure of the reinforcement ring; the literature mentions dislocation rates of 2.7 to 10.6% after revisions not specifically for recurrent dislocation. Revision hip arthoplasty combining dual-mobility sockets with reinforcement ring fixation thus had a relatively low early postoperative complication rate in this challenging group of patients. The design therefore seems to be a valid alternative to constrained implants, especially in high-risk revision cases. Despite the short follow-up period, cemented dual-mobility sockets seem to be a valuable option when reinforcement rings need to be used, with an acceptable dislocation rate in this challenging group of patients. But long-term survival studies are mandatory to evaluate stability and fixation longevity.     

Acetabular reconstruction using morcellised bone with ring support--medium-term results at three to nine years

Marked acetabular bone loss in revision hip arthroplasty is challenging. Reconstruction or reinforcement rings may be used in moderate or severe cases with morcellised bone graft to restore bone stock. We report a single surgeon series of 45 hips over a 5-year period. There were 6 complex primary and 39 revision hip arthroplasties with a mean follow-up of 85 months (range: 42-106). Mean age at surgery was 75.6 years (range: 31-95). Contour (Smith & Nephew) titanium acetabular rings were used in all cases. At time of assessment 12 patients had died; of the 30 alive patients (33 hips), 23 patients (26 hips) were available for clinical evaluation. Forty of 45 grafts healed uneventfully with good graft incorporation, 2 were radiologically loose and both were infected. No loosening occurred in the absence of infection. Based on this experience, we recommend this as a safe and effective technique with low complication rates.     

Mid-Term Results of Graft Augmentation Prosthesis II Cage and Impacted Allograft Bone in Revision Hip Arthroplasty

Background

Several techniques have been described for management of severe acetabular bone defects during revision hip surgery including reconstructive cages. The purpose of this study is to analyze the survival and the mid-term clinical and radiological outcome using the Graft Augmentation Prosthesis (GAP II cage) (Stryker Orthopaedics, Mahwah, NJ) in addition to impaction grafting for acetabular defects in revision hip surgery.

人工髋关节翻修旋转中心重建的临床研究

目的 探讨在人工髋关节翻修手术中,根据Harris窝及髋臼切迹的残存解剖标记,定位髋臼中心点,正确安装髋臼假体和重建髋关节旋转中心的可行性.方法 2007年4月至2009年6月,行28例髋关节翻修术.依据Paprosky分型:Ⅰ型3例,采用生物固定型髋臼假体;ⅡA和ⅡB型8例,采用打压颗粒骨植骨和大直径骨水泥型髋臼假体固定;ⅡC、ⅢA和ⅢB型17例,采用打压颗粒骨植骨和髋臼加强杯固定,其中5例有髋臼内壁穿透者采用结构性和颗粒性植骨.手术中在髋臼切迹连线的垂直平分线上方25～28mm、Harris窝窝内头侧接近原月状软骨面处,定位为原髋臼中心点,以该点为同心圆的圆心安装髋臼杯假体(Ⅰ型)或打压植骨造臼,按照俯倾角40°～45°、前倾角15°～20°安放髋臼加强杯(Ⅱ、Ⅲ型).手术前后摄双侧髋关节正位X线片,测量髋关节旋转中心至两侧泪滴连线的垂直距离和至泪滴的水平距离.分别与术前和健侧比较,评价髋关节旋转中心的重建效果.结果 髋关节旋转中心至两侧泪滴连线的垂直距离:术前为(32.64±4.51)mm,术后为(14.22±3.39)mm,差异有统计学意义(t=3.65,P＜0.05).髋关节旋转中心至泪滴的水平距离:术前为(25.13±3.46)mm,术后为(32.87±4.73)mm,差异有统计学意义(t=2.72,P＜0.05).结论 在髋关节翻修手术中,以残存的Harris窝和髋臼切迹为解剖标记,定位髋臼中心点,能够较准确地安装髋臼假体和有效重建髋关节旋转中心.

Abstract：

Objective To discuss the feasibility of positioning the acetabular center,fixing acetabular implant correctly and reconstructing hip rotation center according to Harris fossa and the remaining anatomical markers of acetabular notch in revision hip arthroplasty.Methods Twenty-eight patients underwent revision hip arthroplasty from April 2007 to June 2009.Based on Paprosky type,3 cases with type Ⅰ were treated with biological fixed acetabular component;8 cases with ⅡA and ⅡB were reconstructed with using of morselized bone grafting and large diameter cemented acetabular prosthesis;17 cases with type ⅡC,ⅢA and ⅢB were treated with using of morselized bone grafting and fixation of acetabular reinforcement ring.Among them,5 patients with massive bone loss in acetabular wall were reconstructed with the use of the structural and morselized bone grafting.The center of the original acetabulum was believed to be in the lunate cartilage surface which was closed to Harris fossa.During the operation,the center was located in the site which was 25-28 mm above in line with perpendicular bisector of acetabular notch connecting line.The acetabular center was the point of positioning acetabular prosthesis (Ⅰ type) or making new acetabulum by impaction bone grafting.Acetabular reinforcement ring (Ⅱ,Ⅲ type) was fixed in accordance with proper transverse angle and anteversion angle.The vertical distance from hip rotation center to teardrop connection and the horizontal distance from hip rotation center to teardrop were measured on preoperative and postoperative radiograph.And the outcomes of reconstruction of rotation center were evaluated.Results The vertical distance was changed from (14.22±3.39) mm preoperatively to (32.64±4.51) mm postoperatively.The difference was statistically significant (t=3.65,P＜ 0.05).The horizontal distance was changed from (25.13±3.46)mm preoperatively to (32.87±4.73) mm postoperatively.The difference was statistically significant (t=2.72,P＜0.05).Conclusion Using residual Harris fossa and acetabular notch as the anatomical markers in revision hip arthroplasty,the restoration of the anatomical hip center has shown to be favorable.     

Bone graft incorporation after revision hip arthroplasty in patients with rheumatoid arthritis, seventy eight revisions using bone allografts with or without metal reinforcements

Purpose

The aim of the study was to assess bone graft incorporation after revision hip arthroplasty in patients with rheumatoid arthritis (RA).

Methods

We report an acetabular reconstruction using impacted, morselized, frozen, radiation sterilized bone allografts in 71 patients suffering from RA. There were sixty-six women and five men at a mean age of 57.5 years. Reconstruction was performed in 78 revision total hip arthroplasties (THAs) for aseptic loosening of acetabular component. The mean follow-up was five years and four months. In 38 cases, a revision was done with use of reinforcement devices.

Results

In four revised hips (10 %) without reinforcement implants, resorption of the allografts was noticed. All Mueller rings and 50 % of unscrews cages (Link, Howmedica) were revised because of aseptic loosening and bone graft resorption. In all of 17 hips with the Burch-Schneider cage, no measurable migration or bone allografts resorption occurred. There were no major general complications.

Conclusions

Acetabular reconstruction with use of morselized, frozen, radiation sterilized bone allografts and the Burch-Schneider cage can be highly successful in managing massive deficiency of acetabular bone stock in revision hip arthroplasty in RA patients.     

Acetabular bone reconstruction in revision arthroplasty: a comparison of freeze-dried, irradiated and chemically-treated allograft vitalised with autologous marrow versus frozen non-irradiated allograft

Deficiencies of acetabular bone stock at revision hip replacement were reconstructed with two different types of allograft using impaction bone grafting and a Burch-Schneider reinforcement ring. We compared a standard frozen non-irradiated bone bank allograft (group A) with a freeze-dried irradiated bone allograft, vitalised with autologous marrow (group B). We studied 78 patients (79 hips), of whom 87% (69 hips) had type III acetabular defects according to the American Academy of Orthopaedic Surgeons classification at a mean of 31.4 months (14 to 51) after surgery. At the latest follow-up, the mean Harris hip score was 69.9 points (13.5 to 97.1) in group A and 71.0 points (11.5 to 96.5) in group B. Each hip showed evidence of trabeculation and incorporation of the allograft with no acetabular loosening. These results suggest that the use of an acetabular reinforcement ring and a living composite of sterile allograft and autologous marrow appears to be a method of reconstructing acetabular deficiencies which gives comparable results to current forms of treatment.     

Mueller reinforcement rings in acetabular revision: outcome in 164 hips followed for 2-17 years

BACKGROUND: In revision hip arthroplasty, cages are commonly used for acetabular reconstruction in cases with loss of bone stock. It is important to follow this patient group closely, in order to better understand failure mechanisms and the chance of long-term success. PATIENTS AND METHODS: We followed our first 164 acetabular revisions with the Mueller reinforcement ring (ARR) in 164 patients, with an average follow-up period of 6 (2-17) years. Mean age at surgery was 69 (29-92) years. 39 patients died (39 hips) during follow-up, but only 3 patients (3 hips) were lost to follow-up. RESULTS: In the observation period, 13 of the hips had to undergo acetabular re-revision for aseptic and septic loosening. Overall survival at 5 years was 95% (CI: 89%-98%) and 90% (CI: 76%-95%) at 8 years using acetabular re-revision or implant removal for all reasons as endpoint. In addition, mechanical and clinical failure was seen in 2 cases. The mean Harris hip score was 70 points, whilst the Merle d'Aubigné score averaged 7 points. Radiolucent lines according to DeLee and Charnley were observed twice in zone I, 6 times in zone II and 14 times in zone III. INTERPRETATION: We found that mid- to long-term survival of the ARR is acceptable. However, failure of the implant due to allograft collapse/resorption or deep infection, and also poor clinical outcome, remain major concerns in acetabular revision arthroplasty. This should be recognized when advising patients.     

Acetabular revision with allograft bone. 103 revisions with 3 reconstruction alternatives, followed for 0.3-13 years.

We reviewed 103 consecutive acetabular revisions in 92 patients, for whom allograft bone and 1 of 3 alternative acetabular components had been used: Harris-Galante cup (HGC, 38 hips), Müller acetabular roof reinforcement ring (ARR, 39 hips), or Burch-Schneider antiprotrusio reinforcement cage (APC, 26 hips). The mean follow-up was 4.5 (0.3-13) years. 7 HGCs, 1 ARR, and 1 APC required revision because of aseptic loosening. Using the endpoint revision because of such loosening, the HGC gave 73% survival after 8 years, the ARR 89% after 13 years, and the APC 94% after 11 years. Using a worst-case criterion, survival was 69% for the HGC after 8 years, 84% for the ARR after 13 years, and 83% for the APC after 11 years. Radiographic incorporation of the allograft, no resorption of the allograft, use of a bulk allograft, male gender, and implantation of a reinforcement device were associated with a lower mechanical failure rate. Good durability of allograft bone in reconstructions of bone deficiencies in acetabular revision surgery can be expected when the implant can bridge the temporary period of mechanical weakness of the allograft. Therefore, in severe acetabular deficiencies, reinforcement devices with sufficiently stable fixation in the host bone should be preferred.     

Revision total hip arthroplasty: analysis of the predictive value of a radiographic classification system for assessment of bone stock loss

AIM: The aim of this study was to evaluate the predictive value of a radiographic classification system concerning implant and bone graft in revision total hip arthroplasty. This classification is used to assess bone stock loss prior to surgery, thus hypothetically enabling an adequate choice of the implant and bone graft required. METHOD: 33 consecutive patients with the diagnosis of aseptic failure of total hip arthroplasty were included in the study. The investigation was performed using the classification system according to Saleh et al. The predictive value was analyzed by comparing the radiographically based recommendation concerning implant and bone graft and the intraoperative procedure according to a blinded observer technique. The Spearman coefficient of correlation (r (s)) was used to establish levels of agreement among multiple ordinal variables. RESULTS: Analysis of correlation between preoperative radiological estimations and intraoperative conclusions concerning implant and bone graft revealed coefficients of correlation (r (s)) of 0.53 (p < 0.01) for the acetabular and of 0.63 (p < 0.01) for the femoral classification. CONCLUSION: Our results indicate that the Saleh classification does not provide sufficient information for preoperative assessment of the revision implant and bone graft required concerning the acetabular side, whereas planning of the operative procedure regarding the femoral implant seems to be possible. These ambivalent findings should be taken into account prior to revision total hip arthroplasty.     

Acetabular reinforcement rings and bone allografts in the reconstructive treatment of periprosthetic bone loss

Medium-term results in the treatment of acetabular bone loss using bulk and/or morselized bone allografts supported by acetabular reinforcement rings are reported. A total of 164 hips in 157 patients were treated by means of this reconstruction technique. The devices employed were Müller ARRR in 24 cases and Burch-Schneider APC in 140. Mean follow-up was 67 months (minimum 12, maximum 123). A total of 4 patients developed deep infection that was treated by resection-arthroplasty. Aseptic loosening of acetabular implant following extensive resorption of bone graft was observed in 5 cases: 3 of the cases underwent acetabular revision. Clinical results were evaluated based on the Harris Hip Score: mean values of 35 and 78 were assessed preoperatively and at follow-up, respectively. X-ray signs of incorporation of bone graft were observed in all cases that progressed successfully.     

Revision Total Hip Arthroplasty Using the Kerboull Acetabular Reinforcement Device and Structural Allograft for Severe Defects of the Acetabulum

Background

The purpose of this study is to review our experience with Kerboull reinforcement device combined with bulk allograft for management of severe acetabular defects.

Early results of revision acetabular cup using antiprotrusio reconstruction rings and allografts

Background:Hip arthroplasty is one of the most frequently performed orthopedic procedures with high scores of success while its most common complication is aseptic loosening of the acetabular component, which may result from host bone loss or even from pelvis discontinuity. The purpose of the study was to evaluate results in patients after revision acetabular arthroplasty with reconstruction rings and allografts.Results:The mean followup period of the patients was 7.2 years (range 3-19 years). A Kaplan–Meier analysis showed that a 3- and 10 year survival rate was 92.8% and 84.8% respectively, using further revision for any reason of the acetabular device as an end point. Eight patients revealed implant related complications. Four patients presented with ring loosening, one with a loose acetabular polyethylene cup, two hips demonstrated recurrent dislocations and one patient was with deep infection. Regarding the remaining 61 patients without re-revision surgery, the mean Harris hip score improved from 30.5 to 73.8 points.Conclusion:A modified, antiprotrusion cage provides an acceptable survival rate and radiological results, but complications could still be expected. It seems that the observed massive bone loss with pelvic discontinuity and an insufficient fixation of the cage to the ischium may result in implant loosening. Stable fixation of the ischial ring flange with screws is an essential condition to expect a good outcome.