High osteolysis and revision rate with the hydroxyapatite-coated ABG hip prostheses65 hips in 56 young patients followed for 5–9 years

Background?There are few reports on the outcome of uncemented HA-coated cups in young patients.Patients?I evaluated the 7-year (5–9) results of HA-coated hip prosthesis (ABG, Stryker) in a consecutive series of 65 primary arthroplasties on 56 patients (mean age 44 years). 2 patients were lost to follow-up and 3 died.Results?The cumulative survival rate with revision for any reason as endpoint at 9 years was 98% (95% CI, 96–100) for the stem, 69% (61–77) for the acetabular metal backing, and 59% (50–67) for the polyethylene liner. 15 of 65 cups were revised on average 6 years after the primary operation and 3 more are planned. Revisions were done in 3 hips because of loosening and migration of the cup, and in 12 hips because of wear and progressive osteolysis around stable components. Only hips with migration had clinical symptoms. Visual inspection of polyethylene liners revealed wear of the articulation in all cases, loosening of the locking mechanism in 10 cases and nonarticular surface deformity in 7 hips. All original stems are in situ although femoral osteolysis was seen in 12 cases and 1 hip was reoperated because of periprosthetic traumatic fracture. Despite the high revision rate, the clinical improvement was good: the average pre- and postoperative Harris Hip Scores at the most recent follow-up were 41 and 90, respectively.Interpretation?While the results on the femoral side were good, the survival rates of the acetabular cups were poor and we stopped using ABG I hip prostheses.     

High osteolysis and revision rate with the hydroxyapatite-coated ABG hip prostheses: 65 hips in 56 young patients followed for 5-9 years

BACKGROUND: There are few reports on the outcome of uncemented HA-coated cups in young patients. PATIENTS: I evaluated the 7-year (5-9) results of HA-coated hip prosthesis (ABG, Stryker) in a consecutive series of 65 primary arthroplasties on 56 patients (mean age 44 years). 2 patients were lost to follow-up and 3 died. RESULTS: The cumulative survival rate with revision for any reason as endpoint at 9 years was 98% (95% CI, 96-100) for the stem, 69% (61-77) for the acetabular metal backing, and 59% (50-67) for the polyethylene liner. 15 of 65 cups were revised on average 6 years after the primary operation and 3 more are planned. Revisions were done in 3 hips because of loosening and migration of the cup, and in 12 hips because of wear and progressive osteolysis around stable components. Only hips with migration had clinical symptoms. Visual inspection of polyethylene liners revealed wear of the articulation in all cases, loosening of the locking mechanism in 10 cases and nonarticular surface deformity in 7 hips. All original stems are in situ although femoral osteolysis was seen in 12 cases and 1 hip was reoperated because of periprosthetic traumatic fracture. Despite the high revision rate, the clinical improvement was good: the average pre- and postoperative Harris Hip Scores at the most recent follow-up were 41 and 90, respectively. INTERPRETATION: While the results on the femoral side were good, the survival rates of the acetabular cups were poor and we stopped using ABG I hip prostheses.     

High revision rate of hydroxyapatite-coated ABG-I prosthesis

Background  

The aim of this study was to investigate the causes of the high revision rate of the hydroxyapatite-coated Anatomique Benoist Girard (ABG-I) prosthesis.     

Biocompatibility of hydroxyapatite-coated hip prostheses

Summary In three patients a mechanically well-fixed Mathys Ceros 80 (Ha) hydroxyapatite-coated acetabular component was revised 2, 5 and 13 months after total hip replacement due to component malposition. In each case there was a thin cellular connective tissue membrane between hydroxyapatite and bone, the main cell type being fibroblast with only occasional giant cells. Immunohistological analysis revealed some MHC locus II antigen positive cells that were identified as monocytes. No interleukin-2 receptor positive cells were found. Under clinical cyclic loading conditions there does not seem to be chemical fixation or bony ingrowth into the hydroxyapatite coated prosthesis component. In human lymphocyte cultures, hydroxyapatite (Interpore 200, particle diameters 15–40 m) did not cause an increase in lymphocyte DNA synthesis as assessed by the³H-thymidine incorporation method on culture days 1, 3 and 5. As analysed with lymphocyte activation markers, the hydroxyapatite-dependent expression of MHC locus II antigen was modest and differed significantly (P < 0.05) from that in culture medium only on day 3. Hydroxyapatite induced only a slight interleukin-2 receptor expression that did not differ from culture medium on days 1, 3 and 5. CD4 and CD8 positive lymphocytes as well as monocytes were not seen attached to hydroxyapatite particles during the culture days. Our findings suggest that hydroxyapatite is an immunologically inert implant material.This work was financially supported by Grants from The Finnish Orthopedics and Traumatology Research Foundation, The Juliana von Wendt Foundation, The Paulo Foundation, The Perklén Foundation, and The Juselius Foundation     

High survival rate of hydroxyapatite-coated hip prostheses: 100 consecutive hips followed for 10 years

We followed 100 consecutive primary total hip replacements with a proximal hydroxyapatite coating for 10 years. No patient was lost to follow-up. 29 patients (32 hips) died before the 10-year follow-up was done; none of their hips had been revised. Thigh pain on activity occurred in 3 hips. We found no radiographic signs of loosening of the femoral components. In course of time the location of dense bone around the femoral stem, which would suggest implant/bone stress transfer, moved distally in 51 of 67 stems after 10 years. No linear or distal osteolysis occurred around the stem. Revision of 1 stem was performed because of thigh pain, but it was found fixed to bone proximally, while 3 cups were revised because of acetabular osteolysis. The 10-year survival of the stem and cup, using revision or pending revision as endpoint, was 100% (95% CI: 99-100) and 97% (95% CI: 94-99), respectively.     

Rheumatoid arthritis and hydroxyapatite-coated hip prostheses: Five-year results

Medium- and long-term results from cemented total hip arthroplasty (THA) in patients with rheumatoid arthritis (RA) show a higher incidence of infection and aseptic loosening when compared to other diagnoses. Early results using uncemented prostheses are variable. Hydroxyapatite (HA) coatings are thought to improve early osseointegration in uncemented THA. In a prospective, international, multicenter clinical study, 32 RA patients who received 33 uncemented HA-coated prostheses were followed up for a minimum of 5 years. Medium-term clinical results are excellent. No infection or aseptic loosening has been recorded. Excellent osseointegration was observed radiographically. Bone remodeling was consistent with mainly proximal to midstem stress transfer. We conclude that uncemented, proximally HA-coated prostheses are a promising alternative to cemented prostheses for RA patients.     

全髋关节置换术中使用广泛性轻磷灰石涂膜人工股骨干的临床研究

目的探讨广泛性轻磷灰石涂膜人工股骨干用于全髋关节置换术进行中期效果的研究。方法从1998年至2004年，共37例患者在全髋关节置换术中使用了广泛性轻磷灰石涂膜人工股骨干，研究项目包括骨内生长、松脱及翻修手术的原因、其他并发症及广泛性轻磷灰石涂膜人工股骨干的存活率。结果平均手术年龄为62．6岁及平均术后随访为5年。在术后4年，1例（2．7％）人工股骨干因深层感染需要拆除，它当时已经是固定良好。在术后1．6年及6．3年，分别有2例（5．4％）出现无菌性松脱沉降需要做翻修术；另外有1例（2．7％）因有其他的临床问题没有翻重修术。3例松脱沉降的患者都在前14例中出现。这3例松脱患者，在x光检查中发现股骨干的尺码相对股骨较细小因而引致松脱。机械式的失败率为8．1％，81％的股骨干被分类为稳定而有骨内生长。如果端点为翻修手术及放射照片松脱，广泛性轻磷灰石涂膜人工股骨干的9年存活率分别为91．2％及93．9％。结论广泛性轻磷灰石涂膜人工股骨干的临床效果可以与广泛性多孔涂膜人工股骨干相媲美。但是，精通手术植入的技巧需要较长时间掌握。     

Treatment of femoral osteolysis with cementless total hip revision

Fifty-nine total hip revision arthroplasties using cementless femoral components were performed in patients with focal femoral osteolytic defects before surgery. Clinical and radiographic review was performed at 2 to 5 years of follow-up evaluation. Osteolytic defects were located by Gruen zones, evaluated on post-operative radiographs, and classified as stabilized, progressive, regressing, healed, or new. There were no clinical failures in this series of patients, and no femoral revisions have been necessary. Progression of the lytic defects after revision did not occur. No new defects developed. Of the 154 preoperative osteolytic defects identified, 27 stabilized, 65 regressed, and 62 healed. One goal of revision hip surgery is to prevent osteolytic lesions from progressing, and this was achieved in 100% of patients in this series. Another goal of revision surgery is restoration of bone stock. It appears that there is a slow, steady remodeling of the lytic lesion that occurs with a well-fixed porous ingrowth prosthesis. Although this series did not show any additional benefit from cancellous allografting, the grafting technique did not use specifically designed instrumentation. Therefore, the full potential of grafting may not have been realized. If severe osteolysis is present, then regression or healing of defects can be achieved by revision to a cementless femoral component with or without the addition of cancellous allograft.     

The ABG hydroxyapatite-coated hip prosthesis: one hundred consecutive operations with average 6-year follow-up

One hundred consecutive ABG (Anatomique Benoist Giraud, Howmedica) hydroxyapatite-coated hip arthroplasties in 97 patients were evaluated prospectively with a follow-up time of 4 to 10 years (mean, 6 years). Clinical results were excellent with an improvement in the Merle d'Aubigne score from 9 preoperatively to 17.4 at 5 years. Thigh pain was persistent in only 3%; it was mild in nature and controlled with simple analgesics. Kaplan-Meyer survivorship analysis was 100% for the femoral stem and 95% for the acetabular cup at 6 years. Of concern was the high polyethylene wear measured with an average of 0.24 mm/y (range, 0.05-0.76 mm/y).     

Hydroxyapatite and revision of femoral hip prostheses

Summary Implants coated with hydroxyapatite (HA) are of very special importance in revisions of total hip prostheses. As far as the fernur is concerned, the rapid bony reconstruction due to the osteoconductive properties which ensure in particular the filling of defects of bony contact guarantee excellent secondary stabilization of the implants, provided that the mechanical assembly secured at operation be stable. The results of a personal series of 46 patients confirm the efficacity of the HA coating by demonstrating the quality of bony reconstruction and the long-term stability of the implants with satisfactory clinical results.     

Risk factors for accelerated polyethylene wear and osteolysis in ABG I total hip arthroplasty

We analysed data from 155 revisions of identical cementless hip prostheses to determine the influence of patient-, implant- and surgery-related factors on the polyethylene wear rate and size of periprosthetic osteolysis (OL). This was calculated by logistic regression analysis. Factors associated with an increased/decreased wear rate included position of the cup relative to Kohler’s line, increase in abduction angle of the cup, traumatic and inflammatory arthritis as a primary diagnosis, and patient height. Severe acetabular bone defects were predicted by an increased wear rate (odds ratio, OR = 5.782 for wear rate above 200 mm³/y), and increased height of the patient (OR = 0.905 per each centimetre). Predictors of severe bone defects in the femur were the increased wear rate (OR = 3.479 for wear rate above 200 mm³/y) and placement of the cup outside of the true acetabulum (OR = 3.292). Variables related to surgical technique were the most predictive of polyethylene wear rate.     

Focal femoral osteolysis after revision hip replacement with a cannulated, hydroxyapatite-coated long-stemmed femoral component: a new route for particulate wear debris

We describe a case of symptomatic focal femoral osteolysis around a screw hole distal to the hydroxyapatite-coated portion of a cannulated femoral component in a revision hip replacement. No locking screw had been inserted into this, the most proximal of the three distal holes for locking screws. The presence of polyethylene wear debris in the tissue excised from the lesion suggested that it had passed through the cannulated portion of the stem and out of the proximal unfilled distal locking hole, initiating an osteolytic reaction in an otherwise well-fixed stem. This case highlights an important design characteristic of such cannulated, uncemented femoral components. We recommend that the proximal aperture of these cannulated stems be occluded at implantation.     

Rapid osteolysis after revision hip arthroplasty in Paget's disease

Rapid bone turnover in Paget's disease has been of concern to many surgeons performing hip arthroplasties. We present the case of a 71-year-old man with Paget's disease affecting the proximal femur. He had undergone total hip arthroplasty 14 years before. He sustained a fracture at the tip of the femoral component, which was managed with revision total hip arthroplasty. His postoperative course was complicated by rapid and profound osteolysis of the femur distal to the fracture site, secondary to disease activity. This case highlights the need for awareness of Paget's disease activity and this potential complication.     

Hydroxyapatite-coated hip prostheses:Difficulties with revision in 4 cases

The introduction of hydroxyapatite ceramic (HAC) coating on hip implants in 1985 (Furlong and Osborn 1991) was hailed as a major advancement for fixation of uncemented prostheses. A problem that is now becoming evident is the extraction of these securely fixed prostheses for purposes of revision. We report on 4 patients who have had HAC-coated prostheses implanted (2 as revision procedures and 2 at primary hip replacement) who had either continuing pain or a proven infection, so that it became necessary to carry out a revision hip arthroplasty. The prostheses were well-fixed and difficult to remove. A transfemoral, longitudinal osteotomy was used in 3 cases.     

Clinical and radiological outcome of hydroxyapatite-coated femoral stem in revision hip arthroplasty

We used a proximally hydroxyapatite-coated femoral stem in revision arthroplasty of 48 cases with aseptic loosening and Paprosky defect class 1 or 2. We reviewed the outcome after 6.1 (4–9.3) years. The clinical outcome was good, with a mean postoperative HHS of 90 (51–100) points. There were five reoperations all on the acetabular side and none for the femoral stem. At follow-up, we observed cancellous sclerosis radiographically in 19 cases—especially in non-tightly fitted stems and mainly in Gruen zones 2 and 6. In 13 cases, cortical thickening was seen, mainly in Gruen zones 3 and 5 and especially in tightly fitted stems. These bony changes were significant and not related to any clinical parameter. They started to appear from 6 months onward, with increasing frequency with longer follow-up. We find that the standard Mallory–Head hydroxyapatite-coated femoral stem is suitable for revision in cases with lower-class femoral defects.

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Résumé Nous avons utilisé une tige fémorale enduite dhydroxyapatite proximale dans larthroplastie de révision de 48 cas avec descellement aseptique et défauts osseux de classe 1 ou 2 selon Paprosky. Nous avons examiné le résultat après 6,1 (4–9,3) années. Le résultat clinique était bon avec un score HHS postopératoire moyen de 90 (51–100) points. Il y avait cinq réopérations, toujours pour des problèmes acétabulaires et jamais pour des problèmes de tige fémorale. Àu dernier recul nous avons observé radiologiquement des densifications spongieuses dans 19 cas—surtout pour des tiges imparfaitement ajustées et principalement dans les zones 2 et 6 de Gruen. Dans 13 cas un épaississement cortical a été noté, principalement dans les zones 3 et 5 et surtout pour les prothèses bien ajustées. Ces différences osseuses étaient significatives, sans rapport avec aucun paramètre clinique. Elles ont commencé à paraître à 6 mois avec une fréquence croissante au cours du suivi. Nous trouvons que la tête-Mallory standard–tige fémorale enduite dhydroxyapatite est convenable pour les révisions avec défauts osseux fémoraux de bas grade.

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Study performed at the Rijnland Hospital, Leiderdorp, The Netherlands     

High rate of infection control with one-stage revision of septic knee prostheses excluding MRSA and MRSE

Background  

The rate of infection control for one-stage revision of infected knee arthroplasties is unclear as are the factors influencing infection control. Such factors include duration of infection and the type of infected prosthesis.     

Acetabular augmentation in primary and revision total hip arthroplasty with cementless prostheses

Twenty-four consecutive cementless hip arthroplasties (13 autografts and 11 allografts) have been done in which large bone grafts were used to augment major acetabular deficiencies and have been followed for a minimum of 24 months with a mean of 34 and a maximum follow-up period of 55 months. The autograft augmentations were uniformly successful. Two fixation failures occurred in the allograft group. Considering the extreme deficiency in the acetabulae encountered and the absence of sufficient autograft material in this group of patients, the use of frozen allografts (although less successful in this series) seems justified. Graft resorption as determined by direct roentgenographic measurements was less than might be expected but may be a manifestation of the short-term follow-up period. Resorption, however, was greater in the allograft group and, when marked, was associated with fixation failure.     

The use of a hydroxyapatite-coated primary stem in revision total hip arthroplasty

Proximal ingrowth of femoral components in total hip arthroplasty (THA) is desirable because it minimizes proximal stress shielding associated with distal ingrowth stems and maximizes bone stock. This is a retrospective evaluation of initial results of revision THA using a proximally hydroxyapatite-coated femoral stem nominally designed for primary use. Patients requiring femoral stem revision were included if they had sufficient femoral bone stock to support a proximally fixed prosthesis (n = 33). This represents 53% of the femoral revisions performed during the period of the study. The average follow-up was 5 years (range 48-88 months). The mean Harris hip and Oxford hip scores were 86.5 and 25.2, respectively. Radiographically, 100% of the stems demonstrated bone ingrowth fixation. These results are superior to previous reports of primary cementless stems for revision THA. The use of a cementless nonmodular implant provides a viable option in some patients undergoing revision THA.     

Autotransfusion in revision total hip arthroplasties using uncemented prostheses

During the period from March 1983 to April 1987, autotransfusion was used in 64 patients treated with cementless revision total hip arthroplasties. An average of 3.9 units of intraoperative blood was salvaged, using a semicontinuous system; 6.5 units were salvaged in patients requiring segmental grafting of the acetabulum and femur. Patients not requiring segmental grafting had only 2.1 units salvaged. The use of homologous banked blood in patients without stored autologous units available was almost three times that of patients with autologous blood. Autotransfusion in the form of autologous transfusions and intraoperative blood salvage accounted for 72% of the total blood requirements. The cell saver is most cost-effective in patients with femur and acetabular bone loss requiring segmental grafting. An autologous transfusion program is important in all patients in whom blood transfusions are expected.