Intermediate-term results after hybrid total hip arthroplasty for the treatment of dysplastic hips

BACKGROUND: In recent studies, good intermediate-term results have been reported after primary hybrid total hip arthroplasty (a cementless acetabular component with a cemented femoral stem) for the treatment of primary osteoarthritis. However, few studies have described the results of this technique in patients with developmental dysplasia of the hip. METHODS: One hundred primary hybrid total hip replacements were performed in ninety patients to treat degenerative arthritis of the hip secondary to developmental dysplasia. Seventy-one patients (eighty-one hips) were available for clinical and radiographic evaluation. The average duration of follow-up was 10.6 years. There were ten men and sixty-one women. Seventy hips were classified as type 1 (dysplasia); seven, as type 2 (low dislocation); and four, as type 3 (high dislocation), according to the classification system of Hartofilakidis et al. RESULTS: At the time of the final follow-up, the average Harris hip score was 86 points. Structural autograft was used in fifteen hips to supplement acetabular coverage. Within five years postoperatively, the acetabular component in six of the fifteen hips had an average of 4.5 mm of vertical migration and an average increase in vertical rotation of 3 degrees, but the position appeared to stabilize thereafter. Revisions were performed in two hips because of recurrent dislocation. No acetabular or femoral component was revised because of aseptic loosening. Osteolysis was identified around two acetabular components and two femoral components. The average rate of polyethylene wear was 0.09 mm per year. CONCLUSIONS: Hybrid total hip arthroplasty for the treatment of symptomatic degenerative arthritis secondary to developmental dysplasia provides favorable results at intermediate-term follow-up. With lower grades of dysplasia, the majority of patients can be treated effectively without a structural bone graft by placement of the cementless acetabular component at a medial or high position.     

The influence of technique on fixation of primary total hip arthroplasty in patients with rheumatoid arthritis

This is a prospective, consecutive study of 98 total hip arthroplasties implanted by 1 surgeon in 66 patients with rheumatoid arthritis. The mean follow-up time was 7.4 years (range, 2-13 years). All 98 acetabular components were uncemented titanium fiber metal-coated components fixed with multiple screws. Sixty-five hips had bulk or cancellous allograft for protrusio acetabuli. Following a prospective protocol based on patient age, 51 hips had an uncemented femoral component, and 47 hips had a cemented femoral component. Using the Harris Hip Score, 30 hips were rated as excellent; 44, good; 15, fair; and 9, poor. There were no early deep infections. One hybrid hip was removed for late metastatic infection at 7 years. Radiographic evaluation of 98 acetabular components showed 1 case of septic loosening, 2 cases of aseptic loosening (1 patient asymptomatic), and 1 case with severe wear and ischial osteolysis. None of the 47 cemented femoral components subsided, and osteolysis was seen in only 3 femora (7%). Of the 51 uncemented femoral components, subsidence occurred in 7 hips (14%), and osteolysis occurred in 15 hips (30%). Uncemented acetabular components have a high rate of success in patients with rheumatoid arthritis who have a total hip arthroplasty. There is a high rate of subsidence and osteolysis, however, with first-generation cementless femoral components.     

Porous-coated total hip arthroplasty in rheumatoid arthritis

Thirty-five porous-coated total hip arthroplasties were implanted in 25 patients with juvenile-onset or adult-onset rheumatoid arthritis and prospectively followed for a mean of 4.5 years (range, 3–6.5 years). Using the Harris hip rating, the mean hip score at the final follow-up evaluation was 91, and 86% of the hips had a good or excellent result. Thirty-one hips had no hip or thigh pain, while four had occasional slight pain. After surgery, 10 patients were employed and the remainder were ambulatory. There were no early or late deep infections. There was one reoperation for recurrent dislocation of the hip, but the components were not removed. Radiographic evaluation of the acetabular component showed that only one component had a complete radiolucent line in all three zones. Three femoral components had nonprogressive subsidence. At this intermediate-term follow-up period, porous-coated total hip arthroplasty is a promising technique that is likely to be successful in young patients with rheumatoid arthritis.     

Acetabular revision after failed total hip arthroplasty in patients with congenital hip dislocation and dysplasia. Results after a mean of 8.6 years

BACKGROUND: Revision of a total hip arthroplasty in a patient who has had congenital hip dysplasia or dislocation is often more difficult than a standard revision operation. The purpose of this study was to assess the efficacy and complications of use of a cementless hemispherical acetabular component for revision of an acetabular component of a failed total hip replacement in patients whose initial problem was arthritis secondary to congenital dislocation or dysplasia. The mean duration of follow-up was approximately eight years. METHODS: We reviewed a consecutive series of sixty-one hips in fifty-three patients who underwent a cementless acetabular revision with use of a hemispherical acetabular component, with or without concurrent femoral revision. Data were collected prospectively. The mean age of the patients at the time of the index operation was fifty-six years. A mean of 1.9 ipsilateral hip operations had been performed previously. Thirty-nine hips (64 percent) had a so-called high hip center prior to the index revision. With one exception, the uncemented acetabular component was fixed with screws. Fifty-one acetabular components were placed with so-called line-to-line fit, and ten were oversized by one to three millimeters. In thirty-eight hips, the femoral component was revised as well. Twenty-nine femora were reconstructed with use of a cemented device, and nine were revised with an uncemented patch-porous-coated femoral stem (a stem on which the porous coating appears in patches). RESULTS: Four patients (five hips) died prior to the five-year minimum follow-up interval. With the exception of one hip treated with resection arthroplasty because of deep infection, none of the hips in these deceased patients had been revised or had a loose component. One living patient (one hip) had a resection arthroplasty, and one additional patient (two hips) had both stable acetabular components rerevised at the time of femoral rerevision at another institution because of loosening and osteolysis. One patient refused to return for follow-up, but the components had not been revised. The remaining fifty-two hips in forty-six patients were followed for a mean of 8.6 years (range, 5.0 to 12.7 years). The mean Harris hip score was 80 points (range, 56 to 100 points) at the time of the latest follow-up. No acetabular component had been revised, although two had migrated. No other acetabular component was loose according to our radiographic criteria. Thus, the mechanical failure rate on the acetabular side was 3 percent (two of sixty-one) for the entire series and 4 percent (two of fifty-two) for the patients who had been followed for a mean of 8.6 years. On the femoral side, the mechanical failure rate was 3 percent (one of twenty-nine) for the cemented stems and six of nine for the uncemented patch-porous-coated stems. CONCLUSIONS: Of the approaches used in this difficult series of patients requiring revision, the hybrid arthroplasty (a cementless acetabular component and a cemented femoral component) yielded overall good results after an intermediate duration of follow-up.     

Precoated femoral component in primary hybrid total hip arthroplasty: results at a mean 10-year follow-up

This is a mid-term report at 10 years' mean follow-up of a study of a precoated femoral component used in primary hybrid total hip arthroplasty (THA). Of an original cohort of 98 hips undergoing THA performed by one surgeon, 75 hips in 65 patients (mean age, 67 years) were prospectively followed up for 7 to 12 years (mean, 10 years). All hips had the same porous coated acetabular component and a precoated femoral component (with an oval cross-section) implanted using Simplex bone cement (Howmedica, Rutherford, NJ). There was no femoral component loosening or revision. Two acetabular components in patients with rheumatoid arthritis and protrusio acetabulae had radiographic loosening; however, only 1 was symptomatic and was revised. Acetabular osteolysis was seen in 4 hips (5.3%), and minor femoral osteolysis was seen in 3 hips (4%). Used in this manner in this patient population, precoating is not detrimental to successful fixation at 10 years' mean follow-up of primary hybrid THA.     

Use of constrained acetabular components for hip instability: an average 10-year follow-up study

The short-term efficacy of using constrained acetabular components for hip instability in the total hip arthroplasty construct has been documented. However, long-term concerns including late dislocation, loosening of components, and osteolysis have not been addressed. The authors evaluated, at an average 10.3-year follow-up, 101 tripolar constrained components (Stryker Howmedica Osteonics) used in the total hip arthroplasty construct. At final follow-up, 6 hips had dislocated or had failure of the constrained component, 5 of which were revised. In addition, 4 hips were revised for aseptic loosening of the acetabular component, 4 hips were revised for aseptic femoral loosening, and 1 hip was revised for acetabular osteolysis. Considering the complexity of the cases, this component has provided durable fixation and hip stability at this intermediate-term follow-up.     

双锥面螺旋臼固定治疗髋关节中心性脱位的中长期临床效果分析

目的 探讨使用双锥面螺旋臼假体固定髋关节中心性脱位病例的长期临床效果.方法 1998年5月至2006年9月北京大学人民医院关节病诊疗研究中心对31例髋关节中心性脱位患者的39侧髋关节行人工全髋关节置换术或翻修术,其中男性12例,女性19例.手术时平均年龄为57.6岁(30～82岁).引起髋关节中心性脱位的病因包括:类风湿关节炎3例6髋;股骨头坏死继发髋关节炎7例12髋,人工股骨头置换术后髋臼磨损11例11髋、髋臼假体松动10例10髋.术中髋臼部分均使用双锥面螺旋臼进行生物学固定.术前Harris评分平均为31.0分(14～61分).结果 所有病例均在术后6个月、1年时随访,2例3髋患者分别因肺癌、急性心肌梗死死亡.24例31髋获得随访,平均随访时间7.4年(5.0～11.5年).末次随访时Harris评分平均为84.7分(70～95分).1例股骨头坏死行双髋同时置换患者术后右髋出现感染,行关节取出骨水泥旷置术,但因内科疾病不稳定未再行翻修术.1例类风湿关节炎患者双髋关节分期手术,术后7年随访时左侧髋臼假体有内侧轻度移位,边缘有透亮线,但患者日常功能好,无疼痛.其余所有病例双锥面螺旋臼假体全部存留,患者日常生活功能良好,对手术效果满意.结论 髋关节中心性脱位使用双锥面螺旋臼的固定效果确切,平均超过7.4年的中长期随访结果显示效果良好.

Abstract：

Objective To discuss long-term clinical results of using Zweymüller cup to treat protrusio acetabuli. Methods From May 1998 to September 2006, 31 patients with 39 hips diagnosed protrusio acetabuli were treated with Zweymtüller cup in total hip arthroplasties or revisions. There were 12 men and 19 women with average age of 57.6 years (from 30 to 82 years). The reasons causing protrusio acetabuli were as followed: rheumatoid arthritis 3 cases 6 hips, osteoarthritis followed femoral head necrosis 7 cases 12 hips, acetabular wear after hemi-arthroplasty 11 cases 11 hips and acetabular component Results All cases were followed up 6 months and one year after operations. Two patients with 3 hips were died for lung cancer and acute myocardial infarction respectively. Twenty-four cases with 31 hips got recent follow-up with average 7. 4 years (from 5.0 to 11.5 years). The average Harris score improved from 31.0 (from 14 to 61) preoperatively to 84. 7(from 70 to 95) postoperatively. There was one infection in right hip after bilateral hip arthroplasty treating by removel prosthesis and cement spacer insert. But until now this patient still did not get revision for her internal medicine. One rheumatoid arthritis patient with two-stage bilateral hip arthroplasty was found slight internal migration and loosening line of left acetabular component,but the patient had no pain with good hip function. All other cases had good hip functions and were very fixations and perfect medium and long-term clinical results for over 7.4 years.     

Total hip arthroplasty in patients with high dislocation: a concise follow-up, at a minimum of fifteen years, of previous reports

We report the updated results at a minimum of fifteen years after eighty-four consecutive total hip arthroplasties performed in sixty-seven female patients with high dislocation of the hip. Sixty-four arthroplasties were performed in forty-nine patients, between 1976 and 1994, with Charnley low-friction acetabular and femoral components inserted with cement; nineteen arthroplasties were performed in seventeen patients, between 1990 and 1994, with the hybrid technique (acetabular component inserted without cement and femoral component inserted with cement); and one arthroplasty was done in 1991, with cementless acetabular and femoral components. All patients were followed prospectively on the basis of clinical assessment according to the Merle D'Aubigné and Postel scoring system, as modified by Charnley, and with radiographic analysis. At the time of the latest follow-up, twenty-six hips (41%) in the low-friction arthroplasty series, ten hips (53%) in the hybrid series, and the one hip with the cementless components had been revised for various reasons. The primary reason for revision in the low-friction arthroplasty group was aseptic loosening of the components (twenty-four hips), whereas the predominant reason for the revisions in the hybrid series and in the hip with cementless components was progressive polyethylene liner wear (six hips). After the minimal follow-up of fifteen years, twenty-five low-friction hip replacements and eight hybrid-type hip replacements had remained intact for an average of twenty-one years (range, seventeen to thirty-two years) and sixteen years (range, fifteen to nineteen years), respectively. These findings may be used in comparisons of results with newer techniques and designs.     

Precoated femoral component in total hip arthroplasty. Results of 5- to 9-year followup.

One hundred nineteen consecutive primary hybrid total hip arthroplasties with a precoated femoral component were performed by one surgeon in 100 patients and followed up prospectively. Ninety-eight hips in 82 patients (mean age, 67 years) were evaluated clinically and radiographically at a mean of 6.5 years (range, 5-9 years). The hips were evaluated clinically using the Harris hip score, and radiographs were evaluated for femoral cement grade, loosening, and osteolysis. Ninety-five hips remained in place at the most recent followup. Two femoral components were revised for definite loosening, and one well fixed femoral component was removed because of late hematogenous infection. Excluding the three hips that were revised, the clinical result was excellent or good in 79 hips (83%), fair in 12 hips (13%), and poor in four hips (4%). All other femoral components were well fixed. There were defects of the cement mantles (C1 and C2) in 90 hips. No femoral component had a stem and cement radiolucent line. Focal femoral osteolysis was seen in only two hips. One acetabular component was removed at 5 years because of late hematogenous infection. One acetabular component had asymptomatic migration. The remaining 96 acetabular components were well fixed. Focal acetabular osteolysis was present in four hips. The mean linear polyethylene wear rate was 0.06 (+/- 0.05) mm per year. In contrast to other reports of early failure and osteolysis, the use of a precoated femoral component in this study did not adversely affect the fixation of hybrid total hip arthroplasty, with definite failure of only 2% (two of 98) of the femoral components.     

Total hip arthroplasty for congenital hip disease

BACKGROUND: It is generally agreed that the clinical and radiographic results of total hip replacement performed for degenerative arthritis secondary to congenital hip disease vary depending on the severity of the anatomical abnormality. In this study, we report the mid-term and long-term clinical and radiographic results of total hip arthroplasty performed for each of the three different types of congenital hip disease. METHODS: Between 1976 and 1994, the senior author performed 229 consecutive primary total hip arthroplasties in 168 patients with osteoarthritis secondary to congenital hip disease. Seventy-six hips were dysplastic, sixty-nine had a low dislocation, and eighty-four had a high dislocation. The Charnley low-friction technique was performed in 178 hips, and the so-called hybrid technique was performed in forty-six hips. Cementless arthroplasty was used in only five hips. RESULTS: After a minimum of seven years of follow-up, the rates of revision of the acetabular components were 15% in the dysplastic hips, 21% in the hips with a low dislocation, and 14% in those with a high dislocation. The rates of revision of the femoral components were 14%, 14%, and 16%, respectively. Survivorship analysis predicted an overall rate of prosthetic survival at fifteen years of 88.8% +/- 4.8% in the dysplastic hips, 73.9% +/- 7.2% in the hips with a low dislocation, and 76.4% +/- 8.1% in those with a high dislocation. CONCLUSIONS: An understanding of the anatomical abnormalities and the use of appropriate techniques and implants make total hip arthroplasty feasible for treatment of the three types of congenital hip disease. In patients with a low dislocation, the major technical problem is reconstruction of the natural acetabulum. In those with a high dislocation, the challenge is to place the acetabular component inside the reconstructed true acetabulum and to use an appropriate femoral implant in the hypoplastic narrow femoral diaphysis.     

Hybrid total hip arthroplasty using specifically-designed stems for patients with developmental dysplasia of the hip. A minimum five-year follow-up study

A 4-U hybrid total hip arthroplasty (THA) system was specifically designed for patients with developmental dysplasia of the hip (DDH). Straight stem with an appropriate offset and various size variations are advantages. We followed 128 hips in 124 patients, 13 men and 111 women, for a mean of 6.5 years (range, 5.0–7.5 years). Two acetabular and femoral components in two patients had been revised for infection, one acetabular component had been revised for recurrent dislocation, and one femoral component had been revised for periprosthetic femoral fracture. None of the acetabular or femoral components were revised for loosening or were found to be loose at follow-up. The Harris hip score increased from a preoperative average of 42 points to 88 points at the most recent follow-up. Primary THA using the 4-U system had a good mid-term result in patients with DDH. This system could be applied for all patients including those with the narrowest and deformed femurs.     

全髋翻修术后假体脱位的预防

目的：探讨采用后方关节囊重建方法对行后外侧入路全髋翻修术后假体脱位的防治作用。方法：本组45例（47髋）经后外侧入路行全髋翻修术的患者，男20例，女25例；平均年龄65岁（55-78岁）。术中将后方关节囊与外旋肌群分别重建固定于前上方原先切开的关节囊断端和大转子顶端的软组织处，回顾性分析术后假体脱位率及脱位的风险因素。股骨假体和髋臼假体均翻修29例（31髋），更换内衬5例（5髋），髋臼、股骨翻修的分别是10例（10髋）和1例（1髋）。第1次翻修的有29例（30髋），第2次翻修的有15例（16髋），第3次翻修的有1例（1髋）。X线评估包括翻修前后下肢长度，髋臼位相，股骨偏心距、前倾角和假体松动。临床功能评价采用Harris评分。结果：45例均获随访，平均随访时间2．7年，除1例感觉前方不稳外，无髋关节感染及脱位发生，该例X线片示髋臼假体过度前倾但无脱位发生。术后所有患者双下肢基本等长，髋臼外展角及前倾角、股骨偏心距和前倾角基本恢复至初次手术前水平。髋臼、股骨假体发生松动各1例。髋关节功能Harris评分由术前平均（49.13±15．53）分升至末次随访的平均（83．59±6.93）分（P〈0．05）。按Harris功能评分标准：优36髋，良5髋，可5髋，差1髋。结论：在假体安放正确、软组织张力恢复满意基础上，后方关节囊及外旋肌群重建有助于降低后外侧入路全髋翻修术后假体脱位的发生率。     

人工髋关节置换术后翻修病例分析

目的分析人工髋关节置换术后翻修的原因,评价全髋翻修术的临床效果。方法本组33例34髋。初次关节置换类型:全髋置换21例,双杯髋关节置换1例,人工股骨头置换11例。翻修原因:无菌性松动23例24髋,髋臼位置不良1例1髋,股骨头置换后髋臼磨损5例5髋,感染4例4髋。翻修距初次手术时间:1年以内5髋,1～2年1髋,5～10年18髋,10～13年10髋。翻修假体类型:非骨水泥型假体20髋,混合型假体7髋,骨水泥型假体7髋。结果平均随访3.5年。1例术后半年发生股骨柄松动进行再翻修,其余病例假体保留,优良率为82.4%。结论翻修的最常见原因为无菌性松动,人工股骨头置换时髋臼磨损也是翻修原因之一,对较年轻的股骨颈骨折患者,如行假体置换,最好采用全髋关节置换。翻修术采用非骨水泥型假体较好。     

Hybrid revision total hip arthroplasty: a 7-year follow-up study

The hybrid method for fixation of total hip arthroplasty (THA) has shown excellent results during the first decade in primary operations. To investigate its role in revision surgery, data on 48 revision THAs in 45 patients that met the inclusion criteria were gathered prospectively, using HGP cementless acetabular components and precoated cemented femoral components inserted with so-called second generation femoral cementing technique in each case. For the 48 hips during an average follow-up period of 7.4 years, no acetabular components was loose or had pelvic lysis. One acetabular component was revised for recurrent dislocation; 1 of 48 femoral components was revised for aseptic loosening and 1 for periprosthetic fracture. Three additional femoral stems (6%) were loose. In this small series, the hybrid concept for revision of failed nonseptic THAs has shown excellent results.     

The fate of revised uncemented acetabular components in patients with rheumatoid arthritis

The results of patients with rheumatoid arthritis who had revision hip arthroplasty have been studied infrequently. The purpose of this study was to review the authors' clinical and radiographic experiences and outcomes with revision hip arthroplasty. Revision total hip arthroplasties were done on 28 patients (30 hips). All hips had morselized bone grafting and four hips had bulk allografts for segmental defects. The mean age of the patients at the time of surgery was 50 years (range, 20-74 years). Patients were followed up for 4 to 15 years (mean, 7 years). At the latest followup, 14 hips (13 patients) of the 30 hips (47%) had good and excellent Harris hip score ratings. Mechanical failures included six hips (five patients) that had revision arthroplasty and two hips (two patients) that had resection arthroplasty. Six other hips (five patients) had poor Harris hip score ratings. The Kaplan-Meier survivorship curve for failure of the acetabular component revealed an 89% chance of survivorship curve for failure of the acetabular component revealed an 89% chance of survival at 60 months and a 44% chance of survival at 108 months. Based on the results of this study, revision hip arthroplasty for acetabular loosening with a cementless acetabular prosthesis has a low rate of success in patients with rheumatoid arthritis.     

Fixation and osteolysis in plasma-sprayed hemispherical cups with hybrid total hip arthroplasty

The optimal surface finish on cementless total hip arthroplasty is still a matter of debate. 145 hips in 130 patients with hybrid total hip arthroplasty using a hemispherical, titanium plasma-sprayed cup were followed for an average of 8.5 years. The average age was 63 years, and the average weight was 165 lb. Three hips were revised for polyethylene wear and synovitis/osteolysis. In all 3 cases, the acetabular component remained well fixed. Radiographically, 5 hips had femoral osteolysis, and 5 sockets had osteolysis in zone 2, with 4 in zone 1. There were no cases of progressive lucent lines, and no acetabular components were revised. Plasma-sprayed acetabular components remain durable up to 12 years. Moreover, in cases with wear particle overload and osteolysis, fixation was maintained at revision surgery.     

Tight fit technique in primary hybrid total hip arthroplasty for patients with hip dysplasia

This article presents the midterm results of hybrid total hip arthroplasty for patients with hip dysplasia by use of a tight fit technique for the femoral component. We followed up 113 hips in 99 patients for a mean of 11 years. All final femoral rasps used in this study overrasped by 0.5 to 1.0 mm for stem insertion, resulting in relatively thin cement mantles. Both components of one hip were removed because of infection. The other 5 acetabular components were revised for osteolysis, recurrent dislocation, or dislodgement of the polyethylene liner. No femoral component was revised for aseptic loosening. We conclude that the tight fit technique using a canal-filling stem may produce good long-term results for patients with hip dysplasia.     

Long-term follow-up of cemented total hip arthroplasty in rheumatoid arthritis

Seventy-five primary cemented total hip arthroplasties (THAs) were performed in 53 patients with rheumatoid arthritis and juvenile rheumatoid arthritis. All patients were followed for an average of 7.4 years, unless their prosthetic hips failed before that time. Clinical evaluation was based on a 10-point maximum rating scale, and ratings for pain, walking, function, and activity improved from preoperative values to the most recent follow-up examination. Revision THA was performed for aseptic acetabular loosening in four hips, and femoral loosening in one hip. Sepsis occurred in another four hips. Complications of wound healing occurred in 14 hips. Roentgenographic evidence of loosening was seen in six acetabular components, in three femoral components, and in the femoral and acetabular component of one hip; none of these hips have as yet required revision THA. The Kaplan-Meier survivorship analysis revealed a 93% survival probability at seven years, which fell to 77% at 12 years in these patients. A trend was that younger, larger patients had increased failure and component loosening rates. Cemented primary THA has been a satisfactory operation in the rheumatoid patient. The relatively high rate of wound healing problems and sepsis may be due to the systemic immune nature of rheumatoid arthritis; however, 25% of these prosthetic hips either failed or are at risk for future failure. Thus, improved techniques are still necessary to increase the long-term success of THA in the rheumatoid patient.     

Second-generation cementless total hip arthroplasty. Eight to eleven-year results.

BACKGROUND: Second-generation cementless femoral components were designed to provide more reliable ingrowth and to limit distal osteolysis by incorporating circumferential proximal ingrowth surfaces. We examined the eight to eleven-year results of total hip arthroplasty with a cementless, anatomically designed femoral component and a cementless hemispheric acetabular component. METHODS: Ninety-two consecutive primary total hip arthroplasties with implantation of a femoral component with a circumferential proximal porous coating (Anatomic Hip) and a cementless hemispheric porous-coated acetabular component (Harris-Galante II) were performed in eighty-five patients. These patients were prospectively followed clinically and radiographically. Six patients (seven hips) died and five patients (seven hips) were lost to follow-up, leaving seventy-four patients (seventy-eight hips) who had been followed for a mean of ten years (range, eight to eleven years). The mean age at the time of the arthroplasty was fifty-two years. RESULTS: The mean preoperative Harris hip score of 51 points improved to 94 points at the time of final follow-up; 86% of the hips had a good or excellent result. Thigh pain was reported as mild to severe after seven hip arthroplasties. No femoral component was revised for any reason, and none were loose radiographically at the time of the last follow-up. Two hips underwent acetabular revision (one because of dislocation and one because of loosening). Kaplan-Meier survivorship analysis was performed with revision or loosening of any component as the end point. The ten-year survival rate was 96.4% +/- 2.1% for the total hip prosthesis, 100% for the femoral component, and 96.4% +/- 2.1% for the acetabular component. Radiolucencies adjacent to the nonporous portion of the femoral component were seen in sixty-eight (93%) of the -seventy-three hips with complete radiographic follow-up. Femoral osteolysis proximal to the lesser trochanter was noted in four hips (5%). No osteolysis was identified distal to the lesser trochanter. Periacetabular osteolysis was identified in twelve hips (16%). Five patients underwent exchange of the acetabular liner because of polyethylene wear. CONCLUSIONS: This second-generation cementless, anatomically designed femoral component provided excellent clinical and radiographic results with a 100% survival rate at ten years. The circumferential porous coating of this implant improved ingrowth and prevented distal osteolysis at a mean of ten years after the arthroplasty.     

Poor outcome of 44 cemented total hip arthroplasties with alumina ceramic heads: clinical evaluation and retrieval analysis after 10-16 years.

We evaluated the long-term results of cemented total hip arthroplasty with alumina ceramic heads in 39 patients (44 hips) from 1981 to 1985. The study comprised 8 men (8 hips) and 31 women (36 hips). Their mean age was 54 (37-76) years and mean weight 52 (34-93) kg. The preoperative diagnoses were osteoarthrosis in 34 patients (38 hips), rheumatoid arthritis in 3 (4 hips) and idiopathic osteonecrosis of the femoral head in 2 (2 hips). The mean duration of follow-up was 13 (10-16) years. At this time, 6 cases had been revised because of aseptic loosening (5 hips showed loosening of both components and 1 acetabular loosening alone). Kaplan-Meier survivorship analysis with radiographic loosening as end-point showed 10-year survival rates of 75% for the acetabular component and 86% for the femoral. The mean linear wear rate of polyethylene was 0.10 mm/year radiographically--i.e., about the same as reported for many metal to polyethylene bearings. 5 alumina ceramic heads were retrieved and showed excellent surface roughness and roundness without scratches. However, debris stuck to the gaps was detected. The debris may act as third-bodies and affect polyethylene wear.