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Conventional radiography is regularly used to evaluate complications after total hip arthroplasty. In various recent consensus meetings, however, plain radiographs of a potentially infected hip joint have been judged as being only relevant to exclude diagnoses other than infection. Solid data on radiographic presentations of periprosthetic joint infection (PJI) are scarce. As a result, the prognostic value of radiological features in low-grade PJI remains uncertain. The present review article aims to present an overview of the available literature and to develop ideas on future perspectives to define the diagnostic possibilities of radiography in PJIs of the hip. The primary outcome of interest of this systematic review was the radiologic presentation of periprosthetic joint infections of the hip. As secondary outcome of interest served the sensitivity and specificity of the radiologic presentation of periprosthetic joint infections. Of the included articles, 26 were reviews, essays, or case reports and only 18 were clinical studies. Typical radiologic abnormalities of PJI were a periosteal reaction, a wide band of radiolucency at the cement-bone or metal-bone interface, patchy osteolysis, implant loosening, bone resorption around the implant, and transcortical sinus tracts. The frequency of their occurrence is still inadequately defined. A deeper understanding of the underlying causes and the relation between microorganisms to radiologic abnormalities can probably help clinicians in the future to diagnose a PJI. This is why further research shall focus on the radiographic features of PJI., (© 2024. The Author(s).)

Aims: Revision total hip arthroplasty in patients with Vancouver type B3 fractures with Paprosky type IIIA, IIIB, and IV femoral defects are difficult to treat. One option for Paprovsky type IIIB and IV defects involves modular cementless, tapered, revision femoral components in conjunction with distal interlocking screws. The aim of this study was to analyze the rate of reoperations and complications and union of the fracture, subsidence of the stem, mortality, and the clinical outcomes in these patients., Methods: A total of 46 femoral components in patients with Vancouver B3 fractures (23 with Paprosky type IIIA, 19 with type IIIB, and four with type IV defects) in 46 patients were revised with a transfemoral approach using a modular, tapered, cementless revision Revitan curved femoral component with distal cone-in-cone fixation and prospectively followed for a mean of 48.8 months (SD 23.9; 24 to 112). The mean age of the patients was 80.4 years (66 to 100). Additional distal interlocking was also used in 23 fractures in which distal cone-in-cone fixation in the isthmus was < 3 cm., Results: One patient (2.2%) died during the first postoperative year. After six months, 43 patients (93.5%) had osseous, and three had fibrous consolidation of the fracture and the bony flap, 42 (91.3%) had bony ingrowth and four had stable fibrous fixation of the stem. No patient had radiolucency around the interlocking screws and no screw broke. One patient had non-progressive subsidence and two had a dislocation. The mean Harris Hip Score increased from of 57.8 points (SD 7.9) three months postoperatively to 76.1 points (SD 10.7) 24 months postoperatively., Conclusion: The 2° tapered, fluted revision femoral component with distal cone-in-cone-fixation, combined with additional distal interlocking in patients with bony deficiency at the isthmus, led to reproducibly good results in patients with a Vancouver B3 fracture and Paprosky type IIIA, IIIB, and IV defects with regard to union of the fracture, subsidence or loosening of the stem, and clinical outcomes., Competing Interests: B. Fink reports royalties or licenses from Aesculap and payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing or educational events from Aesculap and Zimmer Biomet, all of which are unrelated to this study., (© 2024 The British Editorial Society of Bone & Joint Surgery.)

Introduction: In septic two-stage revision surgery, success depends on numerous factors. Key steps are the procedure of ex- and reimplantation and the choice of spacer in the interim phase. The latter is still a matter of debate. Recently, we showed the microbial non-inferiority of a spacer technique using prosthetic cemented implants with an individualized antibiotic mixture in the cement applying a mechanically inferior cementation method. The aim of the present study was to evaluate the clinical results of these spacers in view of either an endofemoral or a transfemoral procedure., Materials and Methods: Our collective consisted of 86 patients (45 endofemoral and 41 transfemoral procedures). The collective was analyzed with respect to complications, reinfection rate and clinical status at the end of the interim phase. Results of an endofemoral and transfemoral approach were compared., Results: With a median Staffelstein-Score of 60 (range 31-81) at the end of the interim phase, the first clinical results are promising. The reinfection-free rate after a median follow-up of 50 months was 90%. Spacer-related complications occurred in 8% of the total collective. Comparing the endo- and transfemoral procedure, there were no statistical differences in complications or regarding the clinical and infectiological outcome., Conclusions: In this study, we were able to show good clinical results for the presented spacer technique. With no relevant difference in outcome, the decision for an endofemoral or transfemoral technique can be based on technical deliberations. Further prospective comparative studies are necessary to show the clinical benefit of this procedure., (© 2023. The Author(s).)

Introduction: A common reason for painful shoulder arthroplasties and revision surgery is a low-grade periprosthetic joint infection (PJI). Diagnosing a low-grade infection is, however, a major diagnostic challenge. This applies even more to the shoulder, which differs from other large joints in terms of clinical features and microbiological spectrum. Aim of this study was to evaluate the diagnostic value of the synovial biopsy in the diagnostic workup of low-grade PJI of the shoulder., Materials and Methods: A retrospective evaluation was conducted on 56 patients receiving revision surgery on their shoulder arthroplasty. A standardized preoperative workup was performed comprising CRP value, leukocyte blood count, synovial fluid microbiological analyses and leukocyte count from joint aspiration, and five synovial biopsy samples for bacteriologic and histologic analysis obtained through an arthroscopic approach. During revision surgery, five samples of periprosthetic tissue were harvested for bacteriologic and histologic analyses. The MSIS-Criteria 2014 were used to evaluate the diagnostic results., Results: In total, 15 of 56 revised prostheses turned out as PJI (27%). When applying our diagnostic workup, we obtained a sensitivity of 67% with a specificity of 95%. When performing a subgroup analysis on those patients that had received diagnostic biopsy, a sensitivity of 100% and a specificity of 83% could be achieved. With a sensitivity and specificity of 90% and 83%, respectively, the biopsy is the single method with the highest diagnostic value., Conclusions: The sensitivity of only 67% of our standard workup emphasizes the difficulty to adequately diagnose low-grade infections after shoulder arthroplasty. The excellent specificity of 95% ensures, however, that non-infected prostheses are not incorrectly explanted. This study highlights that synovial biopsy has a high diagnostic value and should be done prior to complex revision surgeries to raise sensitivity in diagnosing a PJI., (© 2021. The Author(s).)

Background: The reconstruction of the individual anatomy is important in total hip replacement. The aim of the study was to compare two different kinds of stems with respect to the reconstruction of the individual anatomy of the hip., Methods: We compared the restoration of the anatomical parameters (horizontal and vertical offset, femoral neck-shaft angle (NSA) and leg length) of 100 unilateral CoreHip (CH) implantations with 100 unilateral implantations of a standard anatomical stem (Exception (E)). The CoreHip has three different NSAs and exhibits a constant femoral neck length for the different sizes. The Exception stem has a standard and lateralized version with two different NSAs and, in both versions, the femoral neck length increases proportionately with size. The anatomical parameters of the operated and healthy sides were measured and the differences between the two stems compared., Results: The horizontal (2.5 ± 2.8 mm (mean ± SD) for CH vs. 5.4 ± 4.1 mm for E, p < 0.001) and vertical offset (4.1 ± 3.5 mm for CH vs. 5.0 ± 3.8 mm, p = 0.024) and femoral neck-shaft-angle (1.7 ± 1.6 degrees for CH vs. 5.6 ± 3.4 degrees for E, p < 0.001) could be reconstructed significantly better with the CoreHip system. There was a tendency for the leg length (4.0 ± 3.9 mm for CH vs. 4.5 ± 3.8 mm; p = 0.11) to be better restored with the CoreHip., Conclusion: The reconstruction of the individual anatomy of the hip with an endoprosthesis could be realized significantly better with the stem that was designed with three different femoral neck-shaft angles and a constant femoral neck length over different sizes., (© 2022. The Author(s).)

Background: Unexpectedly positive bacterial cultures during prosthesis revision surgery still occur on occasion despite good preoperative diagnostics. In such cases a six-week antibiotic therapy without further surgical intervention is recommended. The aim of this study was to find out how successful this procedure is., Methods: In a study of 508 patients, who required revision surgery of total hip (THA, n = 231) or knee arthroplasties (TKA, n = 277) because of component loosening, biopsy was carried out before their surgery. The collected tissue samples (5) from the biopsy and the revision surgery procedure itself were analyzed according the criteria of the International Consensus Meeting (ICM). Tests revealed 11 patients (7 THA, 4 TKA) with unexpectedly positive bacterial cultures from tissue samples obtained during the revision surgery due to false negative preoperative diagnostic results. These 11 patients were treated with 6 weeks antibiotic therapy and examined with a follow-up of at least 2 years (42.2 ± 16.5 months)., Results: Five patients (2 TKA, 3 THA) became reinfected, resulting in a success rate of 54.5%., Conclusion: Antibiotic therapy alone of an unexpected positive intraoperative bacterial culture in prosthesis revision surgery seems to be less successful than previously assumed.

Aims: Biopsy of the periprosthetic tissue is an important diagnostic tool for prosthetic joint infection (PJI) as it enables the detection of the responsible microorganism with its sensitivity to antibiotics. We aimed to investigate how often the bacteria identified in the tissue analysis differed between samples obtained from preoperative biopsy and intraoperative revision surgery in cases of late PJI; and whether there was a therapeutic consequence., Methods: A total of 508 patients who required revision surgery of total hip arthroplasty (THA) (n = 231) or total knee arthroplasty (TKA) (n = 277) because of component loosening underwent biopsy before revision surgery. The tissue samples collected at biopsy and during revision surgery were analyzed according to the criteria of the Musculoskeletal Infection Society (MSIS)., Results: In total, 178 (113 THA, 65 TKA) were classified as infected. The biopsy procedure had a sensitivity of 93.8%, a specificity of 97.3%, a positive predictive value (PPV) of 94.9%, a negative predictive value (NPV) of 96.7%, and an accuracy of 96.1%. Of the 178 infected patients, 26 showed a difference in the detected bacteria from the biopsy and the revision surgery (14.6%). This difference required a change to antibiotic therapy in only two cases (1.1%)., Conclusion: Biopsy is a useful tool to diagnose PJI, but there may be a difference in the detected bacteria between the biopsy and revision surgery. However, this did not affect the choice of antibiotic therapy in most cases, rendering the clinical relevance of this phenomenon as low. Cite this article: Bone Joint J 2020;102-B(3):329-335.

Background: Preoperative diagnosis of periprosthetic joint infection (PJI) is important because of the therapeutic consequences. The aim of the present study is to investigate whether the serum C-reactive protein (CRP) level can be used as a screening tool for late PJI., Materials and Methods: A cohort of 390 patients with revision surgery of total hip prostheses (200) or total knee prostheses (190) was assessed for late PJI by determining CRP serum level and performing preoperative aspiration with cultivation and intraoperative tissue analyses with cultivation and histologic examination, using the Musculoskeletal Infection Society (MSIS) and International Consensus Meeting (ICM) criteria., Results: A total of 180 joints were rated as PJI (prevalence 46%). Of these, 42.8% (77) showed a CRP level below 10 mg/L and 28.3% (51) showed a normal CRP level of less than 5 mg/L. The 76.9% of the cases with slow-growing bacteria showed a CRP level below 10 mg/L, and 61.5% showed a normal CRP level., Conclusions: Serum CRP level should not be used as a screening tool to rule out late PJI., Level of Evidence: Level 2 (diagnostic study).

Introduction: Modular revision stems with a short distal component can prevent the bypassing of the femoral isthmus and hereby theoretically have advantages concerning risk of periprosthetic fractures, breakage of the junction and a technically easier revision procedure., Materials and Methods: Radiological evaluation of 202 stem revision operations with the modular curved revision stem "Revitan Curved" with a 2° taper was carried out after a mean follow-up period of 7.44 ± 2.09 years (3-13 years) to investigate whether short-stem combinations are effective in Paprosky 2 and 3A defects with respect to rate of subsidence and loosening., Results: Sixty of 62 endofemoral (96.8%) and 137 of 140 transfemoral implantations (97.9%) involved the short, 140 mm distal component. Significant subsidence was seen in 3.3% of cases following endofemoral implantation and in 2.1% of cases following transfemoral implantation. Neither aseptic loosening nor periprosthetic fracture were observed., Conclusion: The use of combinations of short modular components leads to reproducibly good outcomes in femoral revision with respect to subsidence and loosening.

Background: The treatment of periprosthetic infections of hip arthroplasties typically involves use of either a single- or two-stage (with implantation of a temporary spacer) revision surgery. In patients with severe acetabular bone deficiencies, either already present or after component removal, spacers cannot be safely implanted. In such hips where it is impossible to use spacers and yet a two-stage revision of the prosthetic stem is recommended, we have combined a two-stage revision of the stem with a single revision of the cup. To our knowledge, this approach has not been reported before., Questions/purposes: (1) What proportion of patients treated with single-stage acetabular reconstruction as part of a two-stage revision for an infected THA remain free from infection at 2 or more years? (2) What are the Harris hip scores after the first stage and at 2 years or more after the definitive reimplantation?, Methods: Between June 2009 and June 2014, we treated all patients undergoing surgical treatment for an infected THA using a single-stage acetabular revision as part of a two-stage THA exchange if the acetabular defect classification was Paprosky Types 2B, 2C, 3A, 3B, or pelvic discontinuity and a two-stage procedure was preferred for the femur. The procedure included removal of all components, joint débridement, definitive acetabular reconstruction (with a cage to bridge the defect, and a cemented socket), and a temporary cemented femoral component at the first stage; the second stage consisted of repeat joint and femoral débridement and exchange of the femoral component to a cementless device. During the period noted, 35 patients met those definitions and were treated with this approach. No patients were lost to followup before 2 years; mean followup was 42 months (range, 24-84 months). The clinical evaluation was performed with the Harris hip scores and resolution of infection was assessed by the absence of clinical signs of infection and a C-reactive protein level less than 10 mg/L. All patients were assessed before surgery, between stages, every 3 months during the first year after surgery, every 6 months during the second year postoperative, and at latest followup, and were retrospectively drawn from a longitudinally maintained institutional database., Results: Thirty-four of 35 patients (97.2%; 95% CI, 85.4%-99.5%) appeared free of infection by criteria of Masri et al. and Zimmerli et al. at latest followup. The Harris hip score was 61 ± 13 points after the first operation and 82 ± 16 points 2 years after the second operation., Conclusions: This technique is a promising treatment option for periprosthetic infections of the hip in which substantial acetabular defects exclude implantation of a normal spacer and a two-stage revision of the femoral component is favored., Level of Evidence: Level IV, therapeutic study.

Introduction: Patients who have undergone hip or knee replacement surgery are exposed to a high risk of developing a post-operative venous thromboembolus and so have a need for an effective, medication-based, thrombosis prophylaxis. New orally active anticoagulants have been available for a few years now. These specific substances directly block either thrombin (e.g., dabigatran etexilate) or Factor Xa (e.g., apixaban). It is not clear whether there are any efficacy differences between these two substances because there have never been any head-to-head studies carried out., Materials and Methods: We have carried out a study comparing two new orally active anticoagulants dabigatran etexilate (Pradaxa ® ) and apixaban (Eliquis ® ) that were each given to two groups of 200 patients respectively, who had undergone elective hip or knee arthroplasty (100 each). Each patient was assessed for pre- and post-operative hemoglobin concentrations, post-operative blood loss, the number of transfused erythrocyte concentrates, the duration of wound secretion, clinical thromboembolic complications (deep vein thrombosis, pulmonary embolism, myocardial infarct), as well as gastrointestinal, intracranial or wound-related bleeding complications., Results: Dabigatran etexilate treatment led to a significant increase in the duration of wound secretion in both arthroplasty groups when compared to apixaban: wound secretion lasted 1.2 days longer on average in the dabigatran etexilate group than in the apixaban group (4.1 ± 2.1 vs. 2.9 ± 1.8 days). There were no significant differences observed between the two anticoagulant groups when comparing pre- and post-operative Hb values, post-operative blood loss and the other clinical parameters., Conclusions: Thus, it appears that the direct thrombin inhibitor, dabigatran etexilate, is associated with a longer period of wound secretion following the implantation of hip and knee endoprostheses than that associated with the Factor Xa inhibitor, apixaban.

Background: Papers concerning the treatment of periprosthetic infections and acute hematogenous infections often concern inhomogeneous treatment concepts or low numbers of patients; this results in inconsistent rates of treatment success., Methods: Thirty-nine patients with early periprosthetic infections and 28 patients with acute hematogenous infections were treated with a homogeneous concept and followed with a mean period of 41.8 (24-132) months in order to investigate the success rate and influencing factors. All patients were treated with open surgical debridement, a revision of all removable components and irrigation with an antiseptic solution (octinedine). All patients received a systemic vancomycin/rifampicin antibiotic therapy until the microorganism causing the infection could be identified; a specific antibiotic therapy then followed until the end of the sixth week., Results: This unified treatment regimen resulted in an overall success rate of 71.6%, an 82.1% success for early infections and 57.1% for acute hematogenous infections. Variables that influenced the recurrence of an infection were the timespan between revision and first appearance of symptoms (<2 days), the number of previous operations, the American Society of Anesthesiologists classification, and nicotine abuse., Conclusion: It appears that, in cases of early postoperative infection, a reproducibly high rate of success in retaining an implant can be achieved with this specific therapy regime if surgical intervention can be carried out within 2 days of first symptoms., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Background: The value of a transfemoral approach for removal of well-fixed infected hip arthroplasties in 2-stage revision is unclear, especially whether cerclages for closure of the flap in the first step lead to higher reinfection rates and whether reopening of the flap for reimplantation of a hip arthroplasty leads to a lower union rate of the bony flap., Methods: Seventy-six septic 2-stage revisions via a transfemoral approach with cerclages for closure of the flap in the first step and reopening of the flap for reimplantation were followed prospectively for a mean period of 51.2 ± 23.2 (24-118) months., Results: The union rate of the bony flap after reimplantation was 98.7%, and no recurrence of reinfection was recorded in 93.4% of all cases. Subsidence of the stem occurred at a rate of 6.6%, dislocation at a rate of 6.6%, and there was no aseptic loosening of the implants. The Harris Hip Score was 62.2 ± 12.6 points with the spacer and 86.6 ± 15.5 points 2 years after reimplantation. Nine fractures (11.8%) of the flap occurred during the operation because of osteolytic or osteoporotic weakness of the flap itself, but these all healed without further intervention., Conclusion: The transfemoral approach is a safe method for septic revision of well-fixed hip prostheses, and the use of cerclage wires for closing the osteotomy flap in the first stage does not appear to lead to a higher reinfection rate. Similarly, the reopening of the flap does not appear to decrease the union rate of the flap., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Background: The role of the synovial biopsy in the preoperative diagnosis of a periprosthetic joint infection (PJI) of the hip has not been clearly defined., Questions/purposes: We asked whether the value of a biopsy for a PJI is greater than that of aspiration and C-reactive protein (CRP)., Methods: Before revision in 100 hip endoprostheses, we obtained CRP values, aspirated the joint, and obtained five synovial biopsy samples for bacteriologic analysis and five for histologic analysis. Microbiologic and histologic analyses of the periprosthetic tissue during revision surgery were used to verify the results of the preoperative diagnostic methods. The minimum followup was 24 months (median 32; range, 24-47 months)., Results: Forty-five of the 100 prostheses were identified as infected. The biopsy, with a combination of the bacteriologic and histologic examinations, showed the greatest diagnostic value of all the diagnostic procedures and led to a sensitivity of 82% (95% CI, ± 11%), specificity of 98% (95% CI, ± 4%), positive predictive value of 97% (95% CI, ± 5%), negative predictive value of 87% (95% CI, ± 8.3%), and accuracy of 91%., Conclusions: The biopsy technique has a greater value than aspiration and CRP in the diagnosis of PJI of the hip (Masri et al. J Arthroplasty 22:72-78, 2007). In patients with a negative aspirate, but increased CRP or clinical signs of infection, we regard biopsy to be preferable to just repeating the aspiration., Level of Evidence: Level II prognostic study. See Guidelines for Authors for a complete description of levels of evidence.

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., Questions/purposes: We therefore determined: (1) the rate of infection control with one-stage revision of septic knee prostheses, (2) the clinical knee scores that can be achieved, (3) whether the duration of infection or the type of prosthesis influence the level of infection control, and (4) whether different types of prostheses influence the knee scores., Methods: We retrospectively reviewed prospectively collected data from 63 patients who underwent one-stage revisions of septic knee endoprostheses (six unicondylar, 37 primary total knee replacement prostheses, and 20 hinged knee endoprostheses) between 2004 and 2006. All were treated locally and systemically with microorganism-specific antibiotics. For this study we excluded patients with Methicillin-resistant Staphylococcus aureus and Methicillin-resistant Staphylococcus epidermidis or unknown microorganisms. The patients were examined for infection every 3 months and Oxford and Knee Society scores were assessed at the same time. The minimum followup was 24 months (mean followup, 36 months; range, 24-70 months)., Results: None of the patients with replacement unicondylar and primary total knee replacement prostheses had recurrence of infection. Three of the 20 patients with the hinged infected knee prostheses had recurrences; these three patients had chronic infections and had undergone two to three revision operations during at least a 5-year period. The likelihood of infection control was influenced by the duration of infection. The mean Knee Society knee score 24 months after surgery was 72 points (range, 20-98 points), the Knee Society function score was 71 points (range, 10-100 points), and the Oxford-12 knee score was 27 points (range, 13-44 points)., Conclusions: One-stage revision of septic knee prostheses achieved an infection control rate of 95% and higher knee scores than reported for two-stage revisions. Higher rates of recurrent infection appeared to be associated with long-term chronic infections of hinged prostheses.

Objectives: The purpose of the study was to test the hypothesis that stem revision in Vancouver Type B2 and B3 periprosthetic fractures using a transfemoral surgical approach and a modular, noncemented, tapered and fluted revision stem led to reproducibly good results with respect to fracture healing, stability of the prosthesis stem, dislocation, intraoperative fracture, and clinical outcome., Design: Prospective study., Setting: Orthopaedic specialized clinic and center for joint replacement., Patients: Twenty-two patients with periprosthetic fractures of Vancouver Type B2 and 10 of Type B3 were followed of at least 24 months., Main Outcome Measure: Fracture healing, stability of the prosthesis stem, complications, and clinical outcome., Results: All fractures healed with a mean time of 14.5 ± 5.2 weeks. No cases of subsidence of the stem were observed and, according to the classification of Engh et al concerning the biologic fixation of the stem, there was bony ingrowth fixation in 28 cases and stable fibrous fixation in four cases. One dislocation occurred and there were no cases of intraoperative fracture. The Harris hip score rose continually after the operations; from a score 3-months postoperatively of 59.2 ± 14.6 points, it rose to 81.6 ± 16.5 points after 24 months. According to the classification of Beals and Tower, all results were rated as excellent., Conclusions: The methods described here for stem revision lead to reproducibly good results in the treatment of periprosthetic hip fractures of Vancouver Types B2 and B3., Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Background: Although antibiotic-loaded spacers are commonly used to treat periprosthetic infections, it is unclear whether spacers continue to release bactericidal levels of antibiotic 6 weeks after implantation., Questions/purposes: We asked whether an antibiotic can be detected in the tissue surrounding the spacer 6 weeks after implantation and whether the concentration is higher than the minimal inhibition concentration (MIC) previously determined for pathogens that are responsible for most periprosthetic infections., Methods: We removed 14 spacers used in two-stage septic revisions of infected hip prostheses 6 weeks after the primary implantations and determined the concentration of the antibiotics in the membrane formed between the spacer and the neighboring bone on the acetabular and the femoral sides. In seven cases Copal cement with gentamicin and clindamycin were used, and in seven other cases vancomycin was added to the Copal cement. Concentrations of the spacer antibiotics in the neighboring tissue were determined by tandem mass spectroscopy., Results: All three antibiotics were detected in concentrations higher than their MIC. There were no differences between the groups regardless whether vancomycin was added to the cement, or whether the cement was applied with the acetabular cup spacer or with the stem spacer., Conclusions: We concluded that, using the spacer technique described in this study, 6 weeks after spacer implantation, the concentrations of antibiotic are sufficient to treat a periprosthetic infection.

Background: Articulating spacers used in two-stage revision surgery of infected prostheses have the potential to abrade and subsequently induce third-body wear of the new prosthesis., Questions/purposes: We asked whether particulate material abraded from spacers could be detected in the synovial membrane 6 weeks after implantation when the spacers were removed for the second stage of the revision., Patients and Methods: Sixteen hip spacers (cemented prosthesis stem articulating with a cement cup) and four knee spacers (customized mobile cement spacers) were explanted 6 weeks after implantation and the synovial membranes were removed at the same time. The membranes were examined by xray fluorescence spectroscopy, xray diffraction for the presence of abraded particles originating from the spacer material, and analyzed in a semiquantitative manner by inductively coupled plasma mass spectrometry. Histologic analyses also were performed., Results: We found zirconium dioxide in substantial amounts in all samples, and in the specimens of the hip synovial lining, we detected particles that originated from the metal heads of the spacers. Histologically, zirconium oxide particles were seen in the synovial membrane of every spacer and bone cement particles in one knee and two hip spacers., Conclusions: The observations suggest cement spacers do abrade within 6 weeks. Given the presence of abrasion debris, we recommend total synovectomy and extensive lavage during the second-stage reimplantation surgery to minimize the number of abraded particles and any retained bacteria.

A prospective study of 15 patients was designed to examine whether the modular cementless revision stem (Revitan curved; Zimmer GmbH, Winterthur, Switzerland) is suitable for stem revisions with a defective isthmus when distal interlocking screws are also used for fixation. During a follow-up period of 35.4 +/- 11.4 months (24-70 months), there was one stem loosening with screw breakage in a case of a stem that was too thin. According to Engh et al, bony ingrowth fixation of the stem occurred in 12 cases and stable fibrous fixation in 2 cases. The Harris Hip Score rose continuously from 44.7 +/- 12.9 points preoperatively to 75 +/- 10 points at 24 months. This concept of additional stem fixation with distal interlocking screws represents a useful treatment option for revision arthroplasty in rare cases of a defective isthmus., (Copyright (c) 2010 Elsevier Inc. All rights reserved.)

Many concepts have been devised for the treatment of late periprosthetic infections of total hip prostheses. A two-stage revision with a temporary antibiotic-impregnated cement spacer and a cemented prosthesis appears to be the most preferred procedure although, in recent times, there seems to be a trend towards cementless implants and a shorter period of antibiotic treatment. Because of the differences in procedure, not only between studies but also within studies, it cannot be decided which period of parenteral antibiotic treatment and which spacer period is the most suitable. The fact that comparable rates of success can be achieved with different treatment regimens emphasises the importance of surgical removal of all foreign materials and the radical debridement of all infected and ischaemic tissues and the contribution of these crucial procedures to the successful treatment of late periprosthetic infections.

Unlabelled: Cementless two-stage revision of infected total hip prostheses lacks the possibility of local antibiotic protection of the implant at the time of reimplantation, which leads to the concern that this protocol may not sufficiently eradicate periprosthetic infection. Moreover, early implant loosening as much as 18% and stem subsidence as much as 30% have been reported. To determine whether a cementless revision could eradicate infection and achieve sufficient implant stability, we prospectively followed 36 patients with two-stage revisions for septic hip prostheses. We used a uniform protocol of a 6-week spacer interval, specific local and systemic antibiotic therapies, and cementless modular revision stems. The minimum followup was 24 months (mean, 35 months; range, 24-60 months). In one patient, the spacer was changed when the C-reactive protein value failed to normalize after 6 weeks, and the reimplantation was performed after an additional 6 weeks. No infections recurred. There was no implant loosening and a 94% bone-ingrowth fixation of stems. Subsidence occurred in two patients. The Harris hip score increased from a preoperative mean of 41 to 90 at 12 months after reimplantation and later. Using cementless prostheses in two-stage revisions of periprosthetic infections of the hip in combination with a specific local and systemic antibiotic therapy seems to eradicate infection and provide implant stability., Level of Evidence: Level IV, therapeutic study.

Introduction: A prospective study was designed to test the hypothesis that short-term results after hip revisions are in association with the surgical approach with lower clinical scores for the transfemoral approach., Materials and Methods: A total of 120 hip revision operations with the modular cementless revision stem "Revitan Curved" (Zimmer GmbH, Winterthur, Switzerland), of which 42 replacements involved an endofemoral (posterolateral) approach and 78 implantations a transfemoral approach, were followed up over a period of at least 24 months., Results: In the early post-operative stage, stems implanted transfemoral were associated with significantly lower Harris Hip Scores and a significantly more frequent appearance of Trendelenburg signs. The differences lessened at the end of the follow-up period. Within the group of transfemoral implantation, all six stems with a circular fixation zone measuring less than 3 cm had subsided and two of these had become loose; none of the stems with greater fixation zones exhibited these properties. In the case of the endofemoral implants, three stems exhibited sinking but there did not appear to be any relationship between this event and length of fixation zone., Conclusion: The surgical approach has an association with the short-time outcomes of hip revsions using cementless modular stems. Transfemoral implantation of the "Revitan curved" stem requires a fixation zone of at least 3 cm and a longer period of rehabilitation.

Objective: Revision of loose cups of total hip arthroplasties. Implantation and solid fixation of a cementless press-fit cup to restore painless joint function., Indications: Loose cups of total hip arthroplasties. Reimplantation of a prosthetic cup after removal of an infected total hip arthroplasty., Contraindications: Bone defects of the acetabulum precluding a press-fit fixation (at least three-surface fixation) of the cup. Persistent infection., Surgical Technique: Exposure of the acetabulum using a standard approach. Removal of the loose cup. Cleaning of the ground with a spoon. Reaming of a new, deeper center of rotation in the acetabulum using a small reamer. Stepwise reaming of the acetabulum using increasing reamer sizes without pressure until sufficient bone contact at the rim is reached (at least three-surface fixation). Hammering in of a thin-walled cementless press-fit cup (e.g., AllofitStrade mark) of the next size as compared to the reamer chosen last to reach a 4-mm press-fit fixation. Additional screwing in of two to three cancellous screws into the os ilium., Postoperative Management: Thrombosis prophylaxis, physiotherapy, gait training with partial loading of the limb at 10 kg for a period of 6 weeks. Then increased loading by 10 kg per week., Results: 52 cup exchanges using an AllofitStrade mark cup were clinically and radiologically analyzed over an average period of 35.8 +/- 8.8 months (26-53 months). The Harris Hip Score increased from a preoperative value of 46.4 to 87.3 points 2 years postoperatively. Two cups showed migration and one hip dislocated. Loosening has not been observed so far.

The transfemoral approach in its traditional form, using a nonmodular Wagner self-locking revision stem, has the disadvantages of a less predictable union rate of the bony flap and a high rate of stem subsidence. To investigate whether this situation can be improved by using a modified transfemoral approach and modular curved cementless revision stems, we prospectively analyzed 68 hip revisions and followed them clinically and radiographically for a minimum of 24 months (mean +/- standard deviation, 32.4 +/- 11.2 months). One year after the operation, the osteotomy showed bony consolidation in all but one case (98.5%). We noted subsidence in six cases (8.8%) and two of these stems became loose. In all of these cases, the circular fixation zone of the stem in the isthmus of the femur was less than 3 cm. The Harris hip score improved continuously from 41.4 +/- 14.5 points preoperatively to 85.9 +/- 14.6 points 24 months postoperatively. The modified transfemoral approach in combination with a curved, modular revision stem showed reproducibly good results concerning union of the bony flap and subsidence of the stem if the fixation zone was not less than 3 cm.

The aim of this investigation was to analyze the midterm results obtained with the metaphyseal fixation principle of the thrust plate prosthesis (TPP). Survival of 214 implants in 204 patients was analyzed. Clinical (Harris hip score) and radiologic examinations were carried out on 157 of 190 TPP with a postimplantation follow-up period of at least 5 years. Failure rate was 7.0% (9 aseptic and 6 septic loosening). Harris hip score increased from 36.9 +/- 13.5 points preoperatively to 91.2 +/- 13.1 points at follow-up. Eleven TPPs showed radiolucent lines not indicating prosthetic loosening. Thrust plate prosthesis is not an alternative to stemmed endoprostheses. It may be rarely indicated in very young patients where, because of their age, several revision operations can be expected.

Objective: Removal of a loose or fractured stem in total hip arthroplasty. Implantation and secure fixation of a modular uncemented revision stem to restore painless joint function., Indications: Loose and/or broken prosthetic stem. Risk of intraoperative fracture or perforation of the femur when stem revision becomes unavoidable. Periprosthetic fracture., Contraindications: Loose prosthetic stems that can be revised without the risk of perforation or fracture of the femur. Interprosthetic femoral fractures between the ends of hip and knee prosthetic stems that require total replacement of the femur., Surgical Technique: Exposure of the femur anterior to the lateral lip of the linea aspera in the lateral intermuscular septum. 3.2-mm drill holes are made at the anterior and posterior ends of the planned bone flap. Osteotomy of the femur anterior to the junction of the vastus lateralis and the gluteus medius muscles. Posterior osteotomy as well as distal transverse osteotomy between the drill holes and distal anterior osteotomy. The anterior osteotomy is performed using a chisel passed under the vastus lateralis from distal to proximal at the anterior aspect. The osteotomized lateral femoral bone flap with muscle attachment is folded back. Implantation of a modular uncemented revision stem and fixation of the bone flap with double cerclage., Postoperative Management: Thrombosis prophylaxis, physiotherapy, gait training with partial loading of the limb at 10 kg for a period of 6 weeks with hip flexion limited to 70 degrees. Then, free range of movement and increased loading by 10 kg per week., Results: 74 modular uncemented revision stems were implanted in transfemoral technique and the outcomes clinically and radiologically analyzed over an average follow-up period of 20.2 +/- 12.1 months (10-43 months). The Harris Hip Score increased from a preoperative value of 42.21 to 85.97 points after 2 years. Subsidence was observed for four stems and early loosening for two stems. The press-fit anchorage of these latter two stems was < 3 cm.

The nature of the treatment of periprosthetic fractures depends on the localisation, the stability of the prosthesis and the condition of the bone. The Vancouver fracture classification has proved to be of value in determining specific modes of treatment. The current review analyses the different therapeutic options resulting in a concept of fracture-specific treatment. In this report we propose an extended version of this classification in which periprosthetic fractures associated with endoprostheses anchored in the epiphysis or metaphysis, as well as interprosthetic fractures, are taken into consideration.

Introduction: Survivorship analysis was performed on 479 Link V-type threaded cups and on 110 modified V-type Bad Bramstedt cups (a modification of the Link V-type cup since 1993 with a smaller primary coil) to evaluate the effect of the modifications., Materials and Methods: Indication for hip arthroplasty with a Link V-type cup was an inflammatory arthritis in 310 patients, osteoarthritis in 138 patients and dysplastic hip joints in 31 patients. The average follow-up was 8.6+/-3.2 (range 3.0-15.2) years. The 110 modified V-type Bad Bramstedt cups had a mean follow-up period of 4.5+/-0.7 (range 3.0-5.9) years, including 49 with inflammatory arthritis, 49 with osteoarthritis and 12 with dysplastic hip joints. To evaluate the migration rate and radiolucent lines, radiographical examination according to the method of Nunn et al. and Delee and Charnley was performed on 264 Link V-type cups with a mean follow-up period of 8.2+/-2.7 years and 59 modified V-type Bad Bramstedt cups with a mean follow-up period of 4.6+/-0.7 years. Relevant parameters influencing cup migration were analysed., Results: The cumulative survival rate of the former Link V-type acetabular cup was 94.5% after 5 years, 88.1% after 10 years and 70.2% after 15 years. The Bad Bramstedt cup showed a 5-year survivorship rate of 97.9%. Migration of more than 3 mm or tilting of the cup greater than 5 degrees was found in 73% of the former type and in 39% of the modified cup. Radiolucent lines greater than 2 mm and detectable in two zones appeared in 6.4% of the former Link V-type and in 1.7% of the Bad Bramstedt cup design. Among the influencing factors analysed, length of follow-up and primary cup positioning showed a significant correlation to cup migration., Conclusion: The modification of the Link V-type cup showed no satisfactory improvement in cup migration. Therefore, both threaded cups were abandoned in favour of cementless press-fit cups.

Background: The thrust plate prosthesis (TPP) is an implant with a metaphyseal fixation at the proximal femur that transmits the load forces of the hip onto the femoral neck. The osseous incorporation of the TPP and the adaptation of the bone to this force transmission depend on the bone quality, which is reduced to minor vitality and stability in patients with osteonecrosis of the femoral head. Depending on the etiology of the femoral head necrosis, the TPP might lead to early failures., Methods: In a prospective study, 63 patients with 72 cementless TPP due to femoral head osteonecrosis were examined. A clinical and radiological evaluation was performed preoperatively, 3 and 6 months postoperatively, and every year thereafter. The average follow-up period was 4.8+/-1.3 years with a minimum of 3 years. The pathogenesis of femoral head necrosis included alcoholism (n=19), subsequent to renal transplantation (n=11), during cortisone therapy of other dyscrasia (n=9), preceding a polychemotherapy (n=4), diabetes (n=3), sickle cell anemia (n=1), and idiopathic osteonecrosis (n=25)., Results: The Harris Hip Score increased continuously from 50.0 points beyond 79.8 points after 3 months to 86.8 points within the 1st year, and subsequently remained stable at this level. Revision was necessary in six cases (8.3%). Of these, three had an aseptic loosening of the implant: 2 cases with renal transplantation and 1 of alcoholism with an extension of the necrotic area to the seating of the TPP. The other three patients showed septic implant loosenings: 2 cases with renal transplantation and 1 of alcoholism. Radiolucent lines were found in 9 cases (12.5%), mostly in zones 1 and 2 underneath the TPP. Of these, 1 with an idiopathic osteonecrosis was assessed to be radiologically loosened. The overall failure rate was 9.7%, with a proportion of 36.4% in patients with renal transplantation. Excluding this specific patient group, the failure rate was 4.9%., Conclusions: Femoral head necrosis following renal transplantation and extension of the necrotic area into the femoral neck are contraindications for TPP. Excluding these patients, the TPP shows comparable mid-term results to cementless stemmed prostheses and supplies advantages especially for younger patients, because of its metaphyseal, bone-preserving fixation. However, evaluation of the clinical impact of the TPP in comparison with other cementless femoral stem systems requires long-term examinations in the future.