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Abstract
As imaging techniques are ever-evolving, this article aims to provide a brief overview of the various modalities including their limitations. The ability of imaging for evaluation of implant osseo-integration will be addressed and also the role of imaging in assessing septic and aseptic loosening, with a particular focus on adverse tissue reactions, will be discussed. Specific features when imaging the big joints such as shoulder, hip, knee and ankle joint will also be outlined.Overall, a lack of standardisation and validity was noted and despite the gross variety of imaging modalities, there is no technique covering all aspects required for evaluation of implant fixation and septic and aseptic loosening. Each imaging modality has a role, depending on the information required and anticipated. The choice of imaging technique should not be primarily based on medical considerations but also on availability, accessibility, expertise and costs. Plain radiographs alone have been recommended in cases of suspected peri-prosthetic joint infections, given the lack of evidence for additional imaging techniques in this context. For aseptic loosening, ultrasound and plain radiographs may serve as initial screening tools. Metal artefact reducing sequences (MARS) MRI are advancing cross-sectional imaging and are likely to promote their role in patient evaluation.We conclude that imaging is one essential part in the work-up of patients with total joint replacements, within a specific clinical context. Close teamwork between experienced radiologists and orthopaedic surgeons is required for optimal patient care. Cite this article: EFORT Open Rev 2017;2. DOI: 10.1302/2058-5241.2.160058. Originally published online at www.efortopenreviews.org.
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Färber J, Illiger S, Berger F, Gärtner B, von Müller L, Lohmann CH, Bauer K, Grabau C, Zibolka S, Schlüter D, Geginat G. Management of a cluster of Clostridium difficile infections among patients with osteoarticular infections. Antimicrob Resist Infect Control 2017; 6:22. [PMID: 28239451 PMCID: PMC5312516 DOI: 10.1186/s13756-017-0181-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Accepted: 02/08/2017] [Indexed: 01/25/2023] Open
Abstract
Background Here we describe a cluster of hospital-acquired Clostridium difficile infections (CDI) among 26 patients with osteoarticular infections. The aim of the study was to define the source of C. difficile and to evaluate the impact of general infection control measures and antibiotic stewardship on the incidence of CDI. Methods Epidemiological analysis included typing of C. difficile strains and analysis of possible patient to patient transmission. Infection control measures comprised strict isolation of CDI patients, additional hand washings, and intensified environmental cleaning with sporicidal disinfection. In addition an antibiotic stewardship program was implemented in order to prevent the use of CDI high risk antimicrobials such as fluoroquinolones, clindamycin, and cephalosporins. Results The majority of CDI (n = 15) were caused by C. difficile ribotype 027 (RT027). Most RT027 isolates (n = 9) showed high minimal inhibitory concentrations (MIC) for levofloxacin, clindamycin, and remarkably to rifampicin, which were all used for the treatment of osteoarticular infections. Epidemiological analysis, however, revealed no closer genetic relationship among the majority of RT027 isolates. The incidence of CDI was reduced only when a significant reduction in the use of fluoroquinolones (p = 0.006), third generation cephalosporins (p = 0.015), and clindamycin (p = 0.001) was achieved after implementation of an intensified antibiotic stewardship program which included a systematic review of all antibiotic prescriptions. Conclusion The successful reduction of the CDI incidence demonstrates the importance of antibiotic stewardship programs focused on patients treated for osteoarticular infections.
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Singh G, Deutloff N, Maertens N, Meyer H, Awiszus F, Feuerstein B, Roessner A, Lohmann CH. Articulating polymethylmethacrylate (PMMA) spacers may have an immunomodulating effect on synovial tissue. Bone Joint J 2017; 98-B:1062-8. [PMID: 27482018 DOI: 10.1302/0301-620x.98b8.36663] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Accepted: 04/01/2016] [Indexed: 11/05/2022]
Abstract
AIMS Tissue responses to debris formed by abrasion of polymethylmethacrylate (PMMA) spacers at two-stage revision arthroplasty for prosthetic joint infection are not well described. We hypothesised that PMMA debris induces immunomodulation in periprosthetic tissues. PATIENTS AND METHODS Samples of tissue were taken during 35 two-stage revision arthroplasties (nine total hip and 26 total knee arthroplasties) in patients whose mean age was 67 years (44 to 85). Fourier transform infrared microscopy was used to confirm the presence of PMMA particles. Histomorphometry was performed using Sudan Red and Haematoxylin-Eosin staining. CD-68, CD-20, CD-11(c), CD-3 and IL-17 antibodies were used to immunophenotype the inflammatory cells. All slides were scored semi-quantitatively using the modified Willert scoring system. RESULTS The mean CD-68 scores did not show any significant change during the six weeks between the stages. Perivascular and diffuse scores showed significant difference in CD-3, CD-20, CD-11(c) and IL-17. At the time of re-implantation, a shift in the pattern of the expression of dendritic cells towards a perivascular arrangement and towards the periphery of PMMA particles was observed. Positive microbiological cultures were found at the time of re-implantation in three patients. Five further revisions were required for other reasons. CONCLUSION Our results represent a biological reaction of the synovial tissues to spacers with a less diffuse expression of dendritic cells and an increased expression of perivascular lymphocytes. The use of spacers in two-stage revision for infection probably induces an immunomodulation of synovial tissues. Cite this article: Bone Joint J 2016;98-B:1062-8.
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Lohmann CH, Hameister R, Singh G. Allergies in orthopaedic and trauma surgery. Orthop Traumatol Surg Res 2017; 103:S75-S81. [PMID: 28043850 DOI: 10.1016/j.otsr.2016.06.021] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Revised: 05/26/2016] [Accepted: 06/07/2016] [Indexed: 02/02/2023]
Abstract
Hypersensitivity reactions to implants in orthopaedic and trauma surgery are a rare but devastating complication. They are considered as a delayed-type of hypersensitivity reaction (type IV), characterized by an antigen activation of sensitized T-lymphocytes releasing various cytokines and may result in osteoclast activation and bone resorption. Potential haptens are originated from metal alloys or bone-cement. A meta-analysis has confirmed a higher probability of developing a metal hypersensitivity postoperatively and noted a greater risk of failed replacements compared to stable implants. Hypersensitivity to implants may present with a variety of symptoms such as pain, joint effusion, delayed wound/bone healing, persistent secretion, allergic dermatitis (localized or systemic), clicking noises, loss of joint function, instability and failure of the implant. Various diagnostic options have been offered, including patch testing, metal alloy patch testing, histology, lymphocyte transformation test (LTT), memory lymphocyte immunostimulation assay (MELISA), leukocyte migration inhibition test (LIF) and lymphocyte activation test (LAT). No significant differences between in vivo and in vitro methods have been found. Due to unconvincing evidence for screening methods, predictive tests are not recommended for routine performance. Infectious aetiology always needs to be excluded. As there is a lack of evidence on large-scale studies with regards to the optimal treatment option, management currently relies on individual case-by-case decisions. Several options for patients with (suspected) metal-related hypersensitivity exist and may include materials based on ceramic, titanium or oxinium or modified surfaces. Promising results have been reported, but long-term experience is lacking. More large-scaled studies are needed in this context. In patients with bone-cement hypersensitivity, the component suspected for hypersensitivity should be avoided. The development of (predictive) biomarkers is considered as a major contribution for the future.
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Sedlaczek J, Lohmann CH, Lotz EM, Hyzy SL, Boyan BD, Schwartz Z. Effects of low-frequency ultrasound treatment of titanium surface roughness on osteoblast phenotype and maturation. Clin Oral Implants Res 2016; 28:e151-e158. [PMID: 27596293 DOI: 10.1111/clr.12976] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/14/2016] [Indexed: 12/28/2022]
Abstract
OBJECTIVE Low-frequency ultrasound is widely used in the treatment of chronically infected wounds. To investigate its feasibility as a method for in situ restoration of metal implant surfaces in cases of peri-implantitis, we evaluated how low-frequency ultrasound affected surface properties of and response of human osteoblast-like MG63 cells to titanium (Ti). MATERIAL AND METHODS Three Ti surfaces [hydrophobic/smooth (pretreatment, PT); hydrophobic/rough (sandblasted/acid-etched, SLA); and hydrophilic/rough (SLA processed and stored hydrophilicity, mSLA)] were subjected to 25 kHz ultrasound for 10 min/cm2 . Substrate roughness, chemical composition, and wettability were analyzed before and after ultrasound application. Osteoblastic maturation of cells on sonicated disks was compared to cells on untreated disks. RESULTS Ultrasound treatment altered the topography of all surfaces. Contact angles were reduced, and chemical compositions were altered by ultrasound on PT and SLA surfaces. Cell response to sonicated PT was comparable to untreated PT. Alkaline phosphatase was increased on sonicated SLA compared to untreated SLA, whereas DNA, osteocalcin, BMP2, osteoprotegerin, and VEGF-A were unchanged. Cells produced less osteocalcin and BMP2 on sonicated mSLA than on untreated mSLA, but no other parameters were affected. CONCLUSIONS These results show that low-frequency ultrasound altered Ti surface properties. Osteoblasts were sensitive to the changes induced by ultrasound treatment. The data suggest that the effect is to delay differentiation, but it is unclear whether this delay will prevent osseointegration. These results suggest that low-frequency ultrasound may be useful for treating implant surfaces in situ leading to successful re-osseointegration of implants affected by peri-implantitis.
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Drynda A, Ren Q, Buchhorn GH, Lohmann CH. The induction of CXCR4 expression in human osteoblast-like cells (MG63) by CoCr particles is regulated by the PLC-DAG-PKC pathway. J Biomed Mater Res B Appl Biomater 2016; 105:2326-2332. [PMID: 27504737 DOI: 10.1002/jbm.b.33770] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2015] [Revised: 06/13/2016] [Accepted: 07/26/2016] [Indexed: 01/13/2023]
Abstract
BACKGROUND Osteolysis which leads to aseptic loosening of implants is a fundamental problem in joint replacement surgery (arthroplasty) and the leading cause for implant failure and revision surgery. Metal (CoCr) particles separated from implants by wear cause osteolysis and the failure of orthopedic implants, but the molecular mechanism is not clear. The chemokine receptor CXCR4 has been shown to play a pivotal role in periprosthetic osteolysis. The aim of this study was to determine which signal transduction pathway (PLC-DAG-PKC or MAPK/ERK) induces CXCR4 expression in osteoblast-like cells (MG63) cells. METHODS MG63 and Jurkat cells were stimulated with different amounts of particles (107 , 106 , and 105 ) for different time periods (30 min to 24 h), in the presence and absence of specific inhibitors (chelerythrine for the PLC-DAG-PKC pathway and PD98059 for the MAPK/ERK pathway). The expression of CXCR4-specific mRNA was determined by real-time polymerase chain reaction (PCR), and the PKC activity was measured by Western Blot using an antibody specific for PKC-related phosphorylation. RESULTS Real-time PCR data showed that CXCR4 mRNA expression in MG63 cells induced by CoCr particles was significantly diminished by the PKC-specific inhibitor chelerythrine. This effect was not observed with the MAPK/ERK inhibitor PD98059. The involvement of PKC was also confirmed by an intensified phosphorylation pattern after stimulation with CoCr particles. In Jurkat cells, none of the inhibitors exhibited any effect. CONCLUSION The induction of CXCR4-specific mRNA expression in MG63 cells after stimulation with CoCr particles is regulated by the PLC-DAG-PKC pathway and not by the MAPK/ERK pathway. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 2326-2332, 2017.
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Stärke C, Winkelmann U, Glüge S, Becker R, Lohmann CH, Winkelmann U. Interference screw fixation of free tendon grafts: significant time-dependent decrease of the initial contact forces. Knee Surg Sports Traumatol Arthrosc 2016; 24:2353-8. [PMID: 25429763 DOI: 10.1007/s00167-014-3442-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2014] [Accepted: 11/13/2014] [Indexed: 11/24/2022]
Abstract
PURPOSE Interference screw fixation of tendon grafts is a common practice in ACL surgery. Tissues like tendons and bone show a complex viscoelastic behaviour, which could affect the contact forces in interference screw fixation. These effects are not well investigated, especially over prolonged periods of time. The time-dependent behaviour of tendons was thus the subject of the study. It was our hypothesis that a substantial decrease of the contact forces will be observed. METHODS Using an artificial bone surrogate and pig tendons, the time-dependent behaviour of the contact force in a simulated interference screw fixation was investigated over a 12-h period. As the screwing in can have deleterious effects on tendons, two scenarios, screwing in (A) and pressing the screw against the tendon (B), were investigated. RESULTS The initial contact forces showed a magnitude of 1,299 N (A) and 2,156 N (B), respectively. A significant decrease to 530 N (A) and 461 N (B) after 12 h was observed (p < 0.001). However, more than 80 % of the relaxation occurred during the first hour. CONCLUSION Significant relaxation of the contact force in interference screw fixation of ACL grafts occurs, which has implications for research and clinical practice. The strength of ACL fixation methods should not be assessed immediately after assembly of the specimens and comparisons should be done only when the same time intervals from assembly to testing were used. Also, in clinical practice, the initial fixation strength will probably not be maintained. Therefore, a backup fixation might be advisable.
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Berth A, März V, Wissel H, Awiszus F, Amthauer H, Lohmann CH. SPECT/CT demonstrates the osseointegrative response of a stemless shoulder prosthesis. J Shoulder Elbow Surg 2016; 25:e96-103. [PMID: 26652693 DOI: 10.1016/j.jse.2015.09.009] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Revised: 09/07/2015] [Accepted: 09/15/2015] [Indexed: 02/01/2023]
Abstract
BACKGROUND This study evaluates bone remodeling processes in the proximal humerus induced by the implantation of a stemless shoulder prosthesis with regard to time of response and type and extent of bone turnover. METHODS Twenty-eight patients with primary osteoarthritis of the shoulder undergoing a stemless shoulder arthroplasty were prospectively evaluated. The local metabolic bone activity in 5 regions of interest (ROIs 1-5) around the implant and in 1 reference region (ROI ref.) in the humeral diaphysis was analyzed after the application of technetium Tc 99m DPD using single-photon emission computed tomography integrated with multidetector computed tomography (SPECT/CT). The study cohort was divided into 4 groups according to the timing of the most recent follow-up appointment to evaluate the primary osseointegrative response after surgery. The bone uptake values were expressed in target (ROIs 1-5) to nontarget (ROI ref.) ratios. RESULTS No difference within the 4 subgroups with respect to the time of local metabolic bone activity in the ROIs was found at 90 days after surgery. The highest initial metabolic activity and most temporal modifications were found in ROI 1, which was localized in the superior segment of the stem. CONCLUSIONS SPECT/CT data suggest that the primary osseointegration of a stemless shoulder prosthesis is almost completed 3 months after implantation. Variations in metabolic activity pattern in the ROIs during follow-up may be caused by different loading conditions of the bone.
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Chamaon K, Barber H, Awiszus F, Feuerstein B, Lohmann CH. Expression of CD11c in periprosthetic tissues from failed total hip arthroplasties. J Biomed Mater Res A 2015; 104:136-44. [PMID: 26255872 DOI: 10.1002/jbm.a.35549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2015] [Revised: 07/10/2015] [Accepted: 08/03/2015] [Indexed: 11/12/2022]
Abstract
In this work, we characterize integrin CD11c (αXß2) expression in periprosthetic tissues of 45 hip revisions. Tissues were retrieved from 23 ceramic-on-ultra-high molecular weight polyethylene (UHMWPE), 20 metal-on-UHMWPE, and 2 metal-on-metal total hip arthroplasties (THAs). Capsular tissue retrieved during primary THA from 19 patients served as controls. We identified a system to identify important immunohistochemical markers that are expressed in aseptic loosening. We focused on CD11c, CD68 and CD14. We observed that the CD11c molecule possesses four different cellular patterns in the periprosthetic tissues. Three of them are associated with the occurrence of UHMWPE abrasive material. Double staining with CD14 and CD68 was used for a more detailed analysis of the CD11c expressing cells. We observed that all forms of CD11c positive cells are CD68 positive however, only two forms of CD11c expressing cells are positive for CD14. Providing cellular diversity of CD11c expression in periprosthetic tissue, our results provide a contribution toward the further understanding of different cellular mechanisms to foreign body material.
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Dobrindt O, Amthauer H, Krueger A, Ruf J, Wissel H, Grosser OS, Seidensticker M, Lohmann CH. Hybrid SPECT/CT for the assessment of a painful hip after uncemented total hip arthroplasty. BMC Med Imaging 2015; 15:18. [PMID: 26033371 PMCID: PMC4459070 DOI: 10.1186/s12880-015-0056-1] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2014] [Accepted: 04/22/2015] [Indexed: 12/03/2022] Open
Abstract
Background The diagnosis of hip pain after total hip replacement (THR) represents a highly challenging question that is of increasing concern to orthopedic surgeons. This retrospective study assesses bone scintigraphy with Hybrid SPECT/CT for the diagnosis of painful THR in a selected cohort of patients. Methods Bone SPECT/CT datasets of 23 patients (mean age 68.9 years) with a painful hip after THR were evaluated. Selection of the patients required an inconclusive radiograph, normal serum levels of inflammatory parameters (CRP and ESR) or a negative aspiration of the hip joint prior to the examination. The standard of reference was established by an interdisciplinary adjudication-panel using all imaging data and clinical follow-up data (>12 month). Pathological and physiological uptake patterns were defined and applied. Results The cause of pain in this study group could be determined in 18 out of 23 cases. Reasons were aseptic loosening (n = 5), spine-related (n = 5), heterotopic ossification (n = 5), neuronal (n = 1), septic loosening (n = 1) and periprosthetic stress fracture (n = 1). In (n = 5) cases the cause of hip pain could not be identified. SPECT/CT imaging correctly identified the cause of pain in (n = 13) cases, in which the integrated CT-information led to the correct diagnosis in (n = 4) cases, mainly through superior anatomic correlation. Loosening was correctly assessed in all cases with a definite diagnosis. Conclusions SPECT/CT of THA reliably detects or rules out loosening and provides valuable information about heterotopic ossifications. Furthermore differential diagnoses may be detected with a whole-body scan and mechanical or osseous failure is covered by CT-imaging. SPECT/CT holds great potential for imaging-based assessment of painful prostheses.
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Bergschmidt P, Bader R, Ganzer D, Hauzeur C, Lohmann CH, Krüger A, Rüther W, Tigani D, Rani N, Esteve JL, Prats FL, Zorzi C, Madonna V, Rigotti S, Benazzo F, Rossi SMP, Mittelmeier W. Prospective multi-centre study on a composite ceramic femoral component in total knee arthroplasty: Five-year clinical and radiological outcomes. Knee 2015; 22:186-91. [PMID: 25805085 DOI: 10.1016/j.knee.2015.02.003] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Revised: 01/02/2015] [Accepted: 02/01/2015] [Indexed: 02/02/2023]
Abstract
BACKGROUND Enhanced wear resistance of ceramics in general and improved mechanical characteristics of composite ceramics in terms of strength and resistance meet the demands for application in TKA. The aim of this prospective international multi-centre study was to evaluate the 5-year clinical and radiological outcomes of an unconstrained TKA with a composite ceramic femoral component. METHODS A total of 107 patients (109 knees) underwent TKA with the MULTIGEN-PLUS Ceramic Knee at seven centres in three European countries. Clinical and radiological assessments were performed preoperatively and postoperatively at 3, 12, 24 and 60 months, using HSS, WOMAC, SF-36 and standardised radiographs. RESULTS Mean HSS and WOMAC increased significantly from 55.1±11.5 (21-83) and 48.1±16.6 (3-90) preoperatively to 85.6±9.6 (49-98) and 73.3±20.4 (17-100) at 60 months. Mean SF-36 showed significant improvements in patients' quality of life (49.1±17.6 (12-96) preoperatively versus 67.7±23.1 (12-100) at 60 months). Non-progressive radiolucent lines (<1 mm) were observed around the femoral component in four cases. Neither implant migration nor loosening were registered. Kaplan-Meier survivorship was 96.0% at 60 months (92.1-100%, CI 95%). CONCLUSIONS Five-year implant survival rate of the ceramic knee is comparable to other metallic and ceramic unconstrained TKA systems. Although the assessment of long-term implant survivorship is still pending, the ceramic implants represent a promising solution for patients with allergies against metallic components and furthermore for the general osteoarthritis population due to enhanced wear resistance.
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Lohmann CH, Singh G, Willert HG, Buchhorn GH. Metallic debris from metal-on-metal total hip arthroplasty regulates periprosthetic tissues. World J Orthop 2014; 5:660-666. [PMID: 25405095 PMCID: PMC4133474 DOI: 10.5312/wjo.v5.i5.660] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/28/2013] [Revised: 06/20/2014] [Accepted: 07/14/2014] [Indexed: 02/06/2023] Open
Abstract
The era of metal-on-metal (MoM) total hip arthroplasty has left the orthopaedic community with valuable insights and lessons on periprosthetic tissue reactions to metallic debris. Various terms have been used to describe the tissue reactions. Sometimes the nomenclature can be confusing. We present a review of the concepts introduced by Willert and Semlitsch in 1977, along with further developments made in the understanding of periprosthetic tissue reactions to metallic debris. We propose that periprosthetic tissue reactions be thought of as (1) gross (metallosis, necrosis, cyst formation and pseudotumour); (2) histological (macrophage-dominated, lymphocyte-dominated or mixed); and (3) molecular (expression of inflammatory mediators and cytokines such as interleukin-6 and tumor necrosis factor-alpha). Taper corrosion and modularity are discussed, along with future research directions to elucidate the antigen-presenting pathways and material-specific biomarkers which may allow early detection and intervention in a patient with adverse periprosthetic tissue reactions to metal wear debris.
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Drynda A, Singh G, Buchhorn GH, Awiszus F, Ruetschi M, Feuerstein B, Kliche S, Lohmann CH. Metallic wear debris may regulate CXCR4 expression in vitro and in vivo. J Biomed Mater Res A 2014; 103:1940-8. [PMID: 25205627 DOI: 10.1002/jbm.a.35330] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Revised: 08/25/2014] [Accepted: 09/05/2014] [Indexed: 11/05/2022]
Abstract
CXCR4, the chemokine receptor for CXCL12, also known as SDF-1 (stromal cell derived factor-1), has been shown to play a pivotal role in bone metastasis, inflammatory, and autoimmune conditions but has not been investigated in periprosthetic osteolysis. We co-cultured osteoblast-like cells with increasing concentrations of metallic (Co-35Ni-20Cr-10Mo and Co-28Cr-6Mo) and Co-ions simulating wear debris. Real-time polymerase chain reaction (RT-PCR) and Western blotting were used to quantify gene and protein expression of CXCR4. The expression of tumor necrosis factor-alpha (TNF-α) and the effects of AMD3100 (bicyclam) on both CXCR4 and TNF-α expression among these cells was investigated. RT-PCR showed an increase in CXCR4 mRNA (7.5-fold for MG63 and 4.0-fold for SaOs-2 cells) among cells co-cultured with metal alloy particles. Western blotting showed a time-dependent increase in protein expression of CXCR4. The attempted blockade of CXCR4 by its known competitive receptor agonist AMD3100 led to a significant inhibition TNF-α mRNA expression. Immunohistochemistry showed CXCR4 positivity among patients with failed metal-on-metal hip replacements and radiographic evidence of osteolysis. Our data collectively suggest that the CXCR4 chemokine is upregulated in a dose- and time-dependent manner in the presence of metallic wear debris.
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Krueger AP, Singh G, Beil FT, Feuerstein B, Ruether W, Lohmann CH. Ceramic femoral component fracture in total knee arthroplasty: an analysis using fractography, fourier-transform infrared microscopy, contact radiography and histology. J Arthroplasty 2014; 29:1001-4. [PMID: 24360338 DOI: 10.1016/j.arth.2013.11.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2013] [Revised: 10/21/2013] [Accepted: 11/02/2013] [Indexed: 02/01/2023] Open
Abstract
Ceramic components in total knee arthroplasty (TKA) are evolving. We analyze the first case of BIOLOX delta ceramic femoral component fracture. A longitudinal midline fracture in the patellar groove was present, with an intact cement mantle and no bony defects. Fractographic analysis with laser scanning microscopy and white light interferometry showed no evidence of arrest lines, hackles, wake hackles, material flaws, fatigue or crack propagation. Analysis of periprosthetic tissues with Fourier-transform infrared (FT-IR) microscopy, contact radiography, histology, and subsequent digestion and high-speed centrifugation did not show ceramic debris. A macrophage-dominated response was present around polyethylene debris. We conclude that ceramic femoral component failure in this case was related to a traumatic event. Further research is needed to determine the suitability of ceramic components in TKA.
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Singh G, Hameister R, Feuerstein B, Awiszus F, Meyer H, Lohmann CH. Low-frequency sonication may alter surface topography of endoprosthetic components and damage articular cartilage without eradicating biofilms completely. J Biomed Mater Res B Appl Biomater 2014; 102:1835-46. [DOI: 10.1002/jbm.b.33163] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Revised: 03/03/2014] [Accepted: 03/19/2014] [Indexed: 11/09/2022]
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Tat LC, Singh G, Jonathan SBY, Leng LS, Liang S, Awiszus F, Lohmann CH, De SD. Mediolateral subchondral tibial bone mineral density difference does not predict osteoarthritis progression. Orthopedics 2014; 37:e351-6. [PMID: 24762839 DOI: 10.3928/01477447-20140401-55] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2013] [Accepted: 11/08/2013] [Indexed: 02/03/2023]
Abstract
Data on the relationship between osteoporosis and osteoarthritis are conflicting. Most studies report "snapshot" prevalences, and there are few studies evaluating localized knee bone mineral density (BMD) measurements with respect to subsequent osteoarthritis progression. The authors hypothesize that increased mediolateral difference of the proximal tibial BMD may predict progression of knee osteoarthritis. In this study, 246 female volunteers were followed up prospectively over 2 years. Baseline BMD measurements of bilateral proximal (subchondral) tibiae were performed, and the mediolateral BMD ratio was calculated. Precision studies were performed on healthy volunteers to validate the technique. The patients were divided into osteoarthritis progressors and non-progressors based on Kellgren-Lawrence radiographic criteria at 2-year follow-up. Patients who were taking bisphosphonates or who had a history of inflammatory, infectious, or metabolic bone disease and previous hip and knee surgery were excluded. Demographic data, calcium supplementation, physical activity, baseline knee radiographs, and radiographs at 2-year follow-up were obtained. The study was adequately powered to detect an effect size of 0.4. There were 121 progressors and 125 non-progressors. Mean mediolateral BMD ratio was 1.02 among the progressors and 1.01 among the non-progressors (t=0.632, P=.528). Potential confounders were equally distributed among both groups. The data suggest that there is no link between proximal tibial BMD ratio and progression of knee osteoarthritis.
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Singh G, Tan JH, Sng BY, Awiszus F, Lohmann CH, Nathan SS. Restoring the anatomical tibial slope and limb axis may maximise post-operative flexion in posterior-stabilised total knee replacements. Bone Joint J 2013; 95-B:1354-8. [PMID: 24078531 DOI: 10.1302/0301-620x.95b10.31477] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The optimal management of the tibial slope in achieving a high flexion angle in posterior-stabilised (PS) total knee replacement (TKR) is not well understood, and most studies evaluating the posterior tibial slope have been conducted on cruciate-retaining TKRs. We analysed pre- and post-operative tibial slope differences, pre- and post-operative coronal knee alignment and post-operative maximum flexion angle in 167 patients undergoing 209 TKRs. The mean pre-operative posterior tibial slope was 8.6° (1.3° to 17°) and post-operatively it was 8.0° (0.1° to 16.7°). Multiple linear regression analysis showed that the absolute difference between pre- and post-operative tibial slope (p < 0.001), post-operative coronal alignment (p = 0.02) and pre-operative range of movement (p < 0.001) predicted post-operative flexion. The variance of change in tibial slope became larger as the post-operative maximum flexion angle decreased. The odds ratio of having a post-operative flexion angle < 100° was 17.6 if the slope change was > 2°. Our data suggest that recreation of the anatomical tibial slope appears to improve maximum flexion after posterior-stabilised TKR, provided coronal alignment has been restored.
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Becker R, Mauer C, Stärke C, Brosz M, Zantop T, Lohmann CH, Schulze M. Anteroposterior and rotational stability in fixed and mobile bearing unicondylar knee arthroplasty: a cadaveric study using the robotic force sensor system. Knee Surg Sports Traumatol Arthrosc 2013; 21:2427-32. [PMID: 22868351 DOI: 10.1007/s00167-012-2157-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/14/2012] [Accepted: 07/25/2012] [Indexed: 12/22/2022]
Abstract
PURPOSE Different bearing designs in unicondylar knee arthroplasty (UKA) have been developed in order to influence the rate of polyethylene wear. Increased anteroposterior translation and rotation after UKA has been hypothesized due to changes in joint surface geometry. The mobile bearing design was expected to show increased anteroposterior translation compared to the fixed bearing and biconcave bearing design. METHODS Six human cadaver knees were used for the tests. Anteroposterior and rotational knee stability was analysed in 0°, 30°, 60°, 90° and 120° of knee flexion using a robotic testing system (KR 125, KUKA Robots Augsburg, Germany). Three forces and moments were measured in a Cartesian coordinate system with a resolution of 1.0 N and 0.1 Nm. RESULTS There was no difference between the native knees and the knees after UKA in AP translation and rotation in all knee flexion angles. The factor knee flexion angle had a significant impact on the anterior translation when the type of bearing was neglected (p ≤ 0.015). CONCLUSION This study shows that the natural knee stability in AP translation and rotation can be preserved in UKA. The preserved knee stability in different planes after UKA underlines the advantage of UKA when surgery is required in osteoarthritic changes of the medial compartment.
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Lohmann CH, Meyer H, Nuechtern JV, Singh G, Junk-Jantsch S, Schmotzer H, Morlock MM, Pflüger G. Periprosthetic tissue metal content but not serum metal content predicts the type of tissue response in failed small-diameter metal-on-metal total hip arthroplasties. J Bone Joint Surg Am 2013; 95:1561-8. [PMID: 24005196 DOI: 10.2106/jbjs.l.01273] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
BACKGROUND Tissue responses to periprosthetic metal wear debris are complex and poorly understood. There are two predominant tissue responses: a nonspecific macrophage-mediated granulomatous response and lymphocyte-dominated response, which has immunological memory and is mediated by T cells. Delayed hypersensitivity-type responses may accelerate aseptic loosening of arthroplasty implants. We hypothesized that the metal content of periprosthetic tissue but not of serum would be predictive of the type of tissue response to metal wear debris. METHODS We examined twenty-eight total hip arthroplasty implant retrievals from twenty-seven patients who had undergone revision arthroplasty at one institution. Indications for revision were pain and/or osteolysis; one patient had recurrent dislocations. Tissue samples were analyzed microscopically and the metal (Co, Cr, and Ni) content was determined. Explanted prosthetic components were examined for linear wear. Intraoperatively, periprosthetic metallosis was observed in twelve cases and formation of a bursa (pseudotumor) was observed in thirteen. The acetabular cup was loose in eleven cases, the femoral stem was loose in five, and both components were loose in five. RESULTS The metal (Co, Cr, and Ni) content of the periprosthetic tissue ranged from 1.4 to 4604.0 μg/g. Histologically, macrophages containing metal particles as well as diffuse and perivascular lymphocytic infiltration were observed. Fibrin exudation was also visible. Tissues that displayed a predominantly lymphocytic response had a mean metal content of 222.2 ± 52.9 μg/g, whereas those that displayed a macrophage-dominated response had a metal content of 3.0 ± 0.9 μg/g; this difference was significant (p = 0.001). The mean serum metal content did not differ significantly between the two subgroups (60.7 ± 13.4 compared with 43.7 ± 3.8 μg/L, p = 0.105). CONCLUSIONS An association between periprosthetic tissue metal content and hypersensitivity appears likely but needs to be validated with larger-scale retrieval studies. CLINICAL RELEVANCE This study contributes to the understanding of tissue responses to metal wear debris after joint replacement and the factors that are predictive of a type-IV lymphocyte-dominated hypersensitivity reaction.
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Hannemann F, Hartmann A, Schmitt J, Lützner J, Seidler A, Campbell P, Delaunay CP, Drexler H, Ettema HB, García-Cimbrelo E, Huberti H, Knahr K, Kunze J, Langton DJ, Lauer W, Learmonth I, Lohmann CH, Morlock M, Wimmer MA, Zagra L, Günther KP. European multidisciplinary consensus statement on the use and monitoring of metal-on-metal bearings for total hip replacement and hip resurfacing. Orthop Traumatol Surg Res 2013; 99:263-71. [PMID: 23507457 DOI: 10.1016/j.otsr.2013.01.005] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2012] [Revised: 01/21/2013] [Accepted: 01/25/2013] [Indexed: 02/02/2023]
Abstract
INTRODUCTION There is an ongoing debate about the optimal use of metal-on-metal (MoM) bearings in total hip replacement, since there are uncertainties about local and systemic adverse effects due to wear and corrosion of these bearings. Despite various national recommendations, efforts to achieve international harmonization of specific evidence-based recommendations for best practice are still lacking. HYPOTHESIS An international consensus study group should be able to develop recommendations on the use and monitoring of MoM bearings, preferably at the European level, through a multidisciplinary approach, by integrating the perspectives of various stakeholders. MATERIALS AND METHODS Twenty-one experts representing three stakeholder groups and eight countries participated in this European consensus study, which consisted of a consensus meeting, subsequent structured discussion, and consensus voting. RESULTS The current statement defines first of all benefits, local and systemic risks, as well as uncertain issues related to MoM bearings. Safety assessment after implantation of MoM comprises all patients. A closer follow-up is recommended for large head MoM (≥36mm) and resurfacing. In these implants basic follow-up should consist of x-rays and metal ion measurement of cobalt in whole blood, performed with GF-AAS or ICP-MS. Clinical and/or radiographic abnormality as well as elevated ion levels needs additional imaging (ultrasound, CT-scan and/or MARS-MRI). Cobalt values less than 2 μg/L are probably devoid of clinical concern, the threshold value for clinical concern is expected to be within the range of 2-7 μg/L. DISCUSSION This is the first multinational, interdisciplinary, and multiprofessional approach for developing a recommendation for the use and monitoring of MoM bearings in total hip replacement. The current recommendations are in partial agreement with previous statements regarding the extent of follow-up and imaging techniques. They however differ from previous communications regarding measurement of metal ions and especially the investigated medium, technique, and eventual threshold levels. LEVEL OF EVIDENCE Level V, expert opinion/agreement conference.
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Singh G, Meyer H, Ruetschi M, Chamaon K, Feuerstein B, Lohmann CH. Large-diameter metal-on-metal total hip arthroplasties: a page in orthopedic history? J Biomed Mater Res A 2013; 101:3320-6. [PMID: 23529961 DOI: 10.1002/jbm.a.34619] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2012] [Revised: 01/22/2013] [Accepted: 01/23/2013] [Indexed: 01/31/2023]
Abstract
Large-diameter metal-on-metal (MoM) bearings evolved from the success of hip resurfacing. These implants were used in revision surgery in cases with well-fixed acetabular cups but loose or failed femoral stems, to avoid cup revision. Early data showed low rates of dislocation and potentially low wear profiles due to better fluid film lubrication. The risk of impingement was also thought to be low due to the increased head-neck ratio. Subsequently large-diameter MoM heads gained popularity in primary hip replacement. Recent data has emerged on the unacceptably high revision rates among patients with large-diameter MoM total hip arthroplasties (THAs), high blood levels of metal ions, and adverse tissue reactions. The head-neck (cone-taper) modular interface probably represents the weak link in large metal heads that have been used on conventional tapers. Increased torque of the large head, micromotion, and instability at the cone-taper interface, synergistic interactions between corrosion and wear, edge loading, low clearance, and psoas impingement are the likely causes for early failure of these prostheses.
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Stärke C, Kopf S, Lippisch R, Lohmann CH, Becker R. Tensile forces on repaired medial meniscal root tears. Arthroscopy 2013; 29:205-12. [PMID: 23369475 DOI: 10.1016/j.arthro.2012.09.004] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2011] [Revised: 09/05/2012] [Accepted: 09/06/2012] [Indexed: 02/02/2023]
Abstract
PURPOSE The goals of this study were to measure the tensile forces acting on repaired medial meniscal root lesions and to investigate how they depend on femorotibial rotation, flexion, and compressive load. METHODS In 6 human cadaveric knees, the posterior medial meniscal root was completely detached and then repaired with a pullout suture. A force transducer was installed such that it measured tensile forces acting on the suture. The resultant tension at the posterior medial meniscal root was measured for flexion angles up to 120° at 2 levels of femorotibial compressive load (100 and 500 N) in neutral, internal, and external rotation of the knee. RESULTS Rotation had a highly significant effect on root tension (P < .001). Internal rotation of the femur increased the resultant tension, whereas external rotation decreased it. The tension at the meniscal root was related to the femorotibial load (P < .001). Although no significance was reached, a trend toward higher flexion angles causing more tension was observed. The highest mean tension of 60.1 ± 20.2 N was generated with internal rotation, a 500-N load, and 90° flexion. CONCLUSIONS Our study shows in a human in vitro model that motion and weight loading of the knee can generate considerable tensile forces in the posterior medial meniscal root. Internal rotation of the femur increases the resultant tension substantially, whereas external rotation has the opposite effect. CLINICAL RELEVANCE The data can potentially aid the surgeon in finding appropriate rehabilitation exercises after a medial meniscal root repair.
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Meyer H, Mueller T, Goldau G, Chamaon K, Ruetschi M, Lohmann CH. Corrosion at the cone/taper interface leads to failure of large-diameter metal-on-metal total hip arthroplasties. Clin Orthop Relat Res 2012; 470:3101-8. [PMID: 22864616 PMCID: PMC3462871 DOI: 10.1007/s11999-012-2502-5] [Citation(s) in RCA: 130] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND Metal-on-metal (MoM) THAs have reduced wear rates compared with metal-on-polyethylene. However, elevated serum metal ion levels and pseudotumors have been reported in large MoM articulations. QUESTIONS/PURPOSES We therefore determined (1) if corrosion occurred at the cone/taper interface leading to instability in patients with large-diameter THAs; (2) how patients presented clinically and radiographically; (3) if adverse periprosthetic tissue reactions occurred; (4) whether metal was released from the implants into the periprosthetic tissues; and (5) if head size correlated with metal release. METHODS We reviewed 114 patients who had revisions of large-diameter head MoM articulations. Mean time of implantation was 46 months. To identify adverse reactions and particle load, tissues were stained by hematoxylin and eosin and CD3/CD20/CD68 antibodies. Periprosthetic tissues were analyzed for metal content and distribution in different regions. Electrochemical reactions between the stem and adapter were investigated by a minicell electrode. RESULTS Electrochemical studies on the stem and the head adapter showed a risk for galvanic corrosion. Ninety-four percent of patients had instability at the cone/taper interface. All patients presented with early clinical symptoms; 59 patients had radiographic signs of loosening. One hundred four patients had foreign body reactions and necrosis. The largest amounts of metal released were titanium or iron. We found no correlation between head size and metal ion release. CONCLUSIONS These findings suggest that in modular cone/taper connections, friction of the MoM articulations may cause failure of the cone/taper interface leading to galvanic corrosion and loosening. It is unclear whether the design of this MoM system provides sufficient stability at the taper.
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Dobrindt O, Hoffmeyer B, Ruf J, Seidensticker M, Steffen IG, Fischbach F, Zarva A, Wieners G, Ulrich G, Lohmann CH, Amthauer H. Estimation of return-to-sports-time for athletes with stress fracture - an approach combining risk level of fracture site with severity based on imaging. BMC Musculoskelet Disord 2012; 13:139. [PMID: 22866765 PMCID: PMC3485631 DOI: 10.1186/1471-2474-13-139] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2012] [Accepted: 07/30/2012] [Indexed: 12/11/2022] Open
Abstract
Background The aim was to compare the return-to-sports-time (RTST) following stress fractures on the basis of site and severity of injury. This retrospective study was set up at a single institution. Diagnosis was confirmed by an interdisciplinary adjudication panel and images were rated in a blinded-read setting. Methods 52 athletes (female, n = 30; male, n = 22; mean age, 22.8 years) with stress fracture (SFX) who had undergone at least one examination, either MRI or bone scintigraphy, were included. Magnetic resonance images (MRI) and/or bone scintigraphy (BS) of SFX were classified as either low- or high-grade SFX, according to existing grading systems. For MRI, high-grade SFX was defined as visibility of a fracture line or bone marrow edema in T1-, T2-weighted and short tau inversion recovery (STIR) sequences, with low-grade SFX showing no fracture line and bone marrow edema only in STIR and/or T2-weighted sequences. In BS images, a mild and poorly defined focal tracer uptake represented a low-grade lesion, whereas an intense and sharply marginated uptake marked a high-grade SFX. In addition, all injuries were categorized by location as high- or low-risk stress fractures. RTST was obtained from the clinical records. All patients were treated according to a non-weight-bearing treatment plan and comprehensive follow-up data was complete until full recovery. Two-sided Wilcoxon’s rank sum test was used for group comparisons. Results High-risk SFX had a mean RTST of 132 days (d) [IQR 64d – 132d] compared to 119d [IQR 50d – 110d] for low-risk sites (p = 0.19). RTST was significantly longer (p = 0.01) in high-grade lesions [mean, 143d; IQR 66d – 134d] than in low-grade [mean, 95d; IQR 42d – 94d]. Analysis of high-risk SFX showed no difference in RTST (p = 0.45) between high- and low-grade [mean, 131d; IQR 72d – 123d vs. mean, 135d; IQR 63d – 132d]. In contrast, the difference was significant for low-risk SFX (p = 0.005) [low-grade; mean, 61d; IQR 35d – 78d vs. high-grade; mean, 153d; IQR 64d – 164d]. Conclusion For SFX at low-risk sites, the significant difference in RTST between low- and high-grade lesions allows more accurate estimation of RTST by this approach. Both location of the injury and severity determined by imaging should therefore be considered for prediction of RTST.
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Meyer H, Krüger A, Roessner A, Lohmann CH. [Allergic reactions as differential diagnosis for periprosthetic infection]. DER ORTHOPADE 2012; 41:26-31. [PMID: 22273704 DOI: 10.1007/s00132-011-1838-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Metallic orthopedic devices are composed of elements known to be skin sensitizers in the general population and metal-on-metal hip prostheses in particular have the theoretical advantage of producing less abrasive wear than metal-on-polyethylene prostheses. However, there is concern about the possibility of hypersensitivity reactions with typical elicitors, such as nickel, chromium or cobalt. These materials are also used for total knee arthroplasty (TKA) and may elicit an immune response the role of which is still unclear in the outcome of arthroplasty. The immune response is dominated by perivascular T and B lymphocyte tissue infiltration around the hip replacement. The infiltrates are mostly surrounded by so-called high endothelial venules. This reaction is associated with periprosthetic osteolysis and aseptic loosening of the prostheses. The differentiation of hypersensitivity and low-grade infection is initially a diagnosis by exclusion using aspiration cultures. The final diagnosis is only resolved by histological investigation of synovial tissue. A close cooperation between orthopedic surgeons, pathologists and microbiologists is necessary to diagnose specific cellular differences in hypersensitivity and infection in tissue investigations.
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