Jan Geurts - Academia.edu (original) (raw)
Papers by Jan Geurts
Management of Periprosthetic Joint Infections (PJIs), 2017
Multiple difficulties occur during treatment of different orthopedic infections such as biofilm f... more Multiple difficulties occur during treatment of different orthopedic infections such as biofilm formation, osteonecrosis, destruction of bone matrix, and compromised soft tissues and vascularization. Biomaterials can be used to treat the infection and to solve the different treatment difficulties. These biomaterials can elicit local antibacterial therapy, which is necessary for optimal treatment of orthopedic infections. Furthermore, they can also be used as a bone defect filler after debridement surgery. Different types of biomaterials are developed: antibiotic-loaded collagen fleeces and ceramic or composite calcium-based bone graft substitutes as calcium sulfates, calcium phosphates, and hydroxyapatite. Another biomaterial used in treatment of these infections is bioactive glass. In this chapter, the properties of different biomaterials regarding treatment of infection are elucidated and the clinical results of these biomaterials in treatment of chronic osteomyelitis are discussed.
People interested in the research are advised to contact the author for the final version of the ... more People interested in the research are advised to contact the author for the final version of the publication, or visit the DOI to the publisher's website. • The final author version and the galley proof are versions of the publication after peer review. • The final published version features the final layout of the paper including the volume, issue and page numbers. Link to publication General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. • Users may download and print one copy of any publication from the public portal for the purpose of private study or research. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal. If the publication is distributed under the terms of Article 25fa of the Dutch Copyright Act, indicated by the "Taverne" license above, please follow below link for the End User Agreement:
Journal of Bone and Joint Infection, 2021
Introduction: Chronic osteomyelitis is a challenging condition in the orthopedic practice and tra... more Introduction: Chronic osteomyelitis is a challenging condition in the orthopedic practice and traditionally treated using local and systemic antibiotics in a two-stage surgical procedure. With the introduction of the antimicrobial biomaterial S53P4 bioactive glass (Bonalive ®), chronic osteomyelitis can be treated in a one-stage procedure. This study evaluated the mid-term clinical results of patients treated with S53P4 bioactive glass for long bone chronic osteomyelitis. Methods: In this prospective multi-center study, patients from two different university medical centers in the Netherlands were included. One-stage treatment consisted of debridement surgery, implantation of S53P4 bioactive glass, and treatment with culture-based systemic antibiotics. If required, wound closure by a plastic surgeon was performed. The primary outcome was the eradication of infection, and a secondary statistical analysis was performed on probable risk factors for treatment failure. Results: In total, 78 patients with chronic cavitary long bone osteomyelitis were included. Follow-up was at least 12 months (mean 46; standard deviation, SD, 20), and 69 patients were treated in a one-stage procedure. Overall infection eradication was 85 %, and 1-year infection-free survival was 89 %. Primary closure versus local/muscular flap coverage is the only risk factor for treatment failure. Conclusion: With 85 % eradication of infection, S53P4 bioactive glass is an effective biomaterial in the treatment of chronic osteomyelitis in a one-stage procedure. A major risk factor for treatment failure is the necessity for local/free muscle flap coverage. These results confirm earlier published data, and together with the fundamentally different antimicrobial pathways without antibiotic resistance, S53P4 bioactive glass is a recommendable biomaterial for chronic osteomyelitis treatment and might be beneficial over other biomaterials. 1 Introduction Chronic osteomyelitis is a bacterial infection of the bone and bone marrow and is one of the biggest clinical challenges in current orthopedic practice. It is predominantly posttraumatic and is often seen after orthopedic (open) fracture surgery but can also be caused by a hematogenous spread or direct postoperative colonization (Lazzarini et al., 2004; Lew and Waldvogel, 2004). Treatment of these infections is difficult because the infected bone and the surrounding tissues are often devitalized (i.e., dead bone sequesters) and poorly vascularized due to the (mostly) long-term present infection. In combination with risk factors as smoking, peripheral vascular disease, diabetes or malnutrition, patients often need multiple surgical procedures where the risks of reinfection
Journal of Orthopaedic Research, 2020
Chronic osteomyelitis has always been a therapeutic challenge for patient and surgeon due to the ... more Chronic osteomyelitis has always been a therapeutic challenge for patient and surgeon due to the specific problems related with bone infection and bacterial biofilm eradication. Other than being the cause of infection or facilitating spread or persistence of infection, biomaterials are also becoming a tool in the treatment of infection. Certain novel biomaterials have unique and ideal properties that render them perfectly suited to combat infection and are therefore used more and more in the treatment of chronic bone infections. In case of infection treatment, there is still debate whether these properties should be focused on bone regeneration and/or their antimicrobial properties. These properties will be of even greater importance with the challenge of emerging antimicrobial resistance. This review highlights indications for use and specific material properties of some commonly used contemporary biomaterials for this indication as well as clinical experience and a literature overview. This article is protected by copyright. All rights reserved.
SA Orthopaedic Journal, 2018
Aim: Chronic osteomyelitis is still a difficult problem to treat in the developed world, but even... more Aim: Chronic osteomyelitis is still a difficult problem to treat in the developed world, but even more so in low-and middle-income countries. Contemporary treatment options result in satisfying outcomes in a setting with abundant resources, but the question is whether these treatment options can be translated to other, less supported health care systems and if they obtain the same results. Methods: Eighteen patients with established chronic osteomyelitis (eight type III, ten type IV) were prospectively enrolled and treated in a one-stage procedure with radical debridement and dead space management using bioactive glass S53P4 granules, together with adjuvant antibiotic therapy. Results: Thirteen patients were assessed at 24 months. Infection control was achieved in five patients (38%). Eight patients (61.5%) had persistence or recurrence of infection. Loss to follow-up was substantial (five patients, 28%). Conclusion: Due to specific challenges treating chronic osteomyelitis in low-and middle-income countries, contemporary treatment options cannot be 'copy-pasted' with the same results in these settings.
Materials, 2019
Bioactive glass (BAG) granules (S53P4) have shown good clinical results in one-stage treatment of... more Bioactive glass (BAG) granules (S53P4) have shown good clinical results in one-stage treatment of osteomyelitis. During this treatment, a cortical window is created, and infected bone is debrided, which results in large defects that affect the mechanical properties of the bone. This study aimed to evaluate the role of BAG granules in load-bearing bone defect grafting. First, the influence of the geometry of the cortical window on the bone bending stiffness and estimated failure moments was evaluated using micro finite element analysis (µFE). This resulted in significant differences between the variations in width and length. In addition, µFE analysis showed that BAG granules contribute to bearing loads in simulated compression of a tibia with a defect grafted with BAG and a BAG and bone morsel mixture. These mixtures potentially can unload the cortical bone that is weakened by a large defect directly after the operation by up to approximately 25%, but only in case of optimal load tr...
Materials, 2019
This study was set up to evaluate the costs of a one-stage treatment of chronic osteomyelitis usi... more This study was set up to evaluate the costs of a one-stage treatment of chronic osteomyelitis using bioactive glass S53P4 versus a two-stage treatment using gentamicin-loaded PMMA beads. Furthermore, a cost-effectiveness analysis was performed from a hospital’s perspective together with the evaluation of clinical outcome. A treatment group (n = 25) receiving one-stage surgery with bioactive glass was retrospectively compared with a two-stage control group (n = 25). An assessment was made of all costs included from first outpatient visit until one year after treatment. Bootstrap simulation and sensitivity analyses were performed. The primary endpoint was cost-effectiveness with clinical outcome as the secondary endpoint. The base case analyses shows dominance of the one-stage treatment with bioactive glass S53P4 due to lower costs and a better clinical outcome. Sensitivity analyses confirm these findings. This study is the first in its kind to show one-stage treatment of chronic oste...
European Journal of Hybrid Imaging, 2019
Background: Magnetic resonance imaging (MRI) and 2-[18F]-fluoro-2-deoxy-Dglucose (FDG) positron e... more Background: Magnetic resonance imaging (MRI) and 2-[18F]-fluoro-2-deoxy-Dglucose (FDG) positron emission tomography paired with computed tomography (PET/CT) are two commonly used imaging modalities in the complicated diagnostic workup of osteomyelitis. Diagnosis using these modalities relies on, respectively, anatomical (MRI) and metabolic (PET) signs. With hybrid PET/MRI being recently available, our goal is to qualitatively compare hybrid FDG PET/MRI to FDG PET/CT in the diagnosis and operative planning of chronic osteomyelitis. Methods: Five patients with suspected chronic osteomyelitis in an extremity underwent an 18 F-FDG single-injection/dual-imaging protocol with hybrid PET/CT and hybrid PET/MR. Images and clinical features were evaluated using a standardized assessment method. Standardized uptake value (SUV) measurements were performed on all images. Concordant and discordant findings between PET/MRI and PET/CT were analysed. Results: The consensus diagnoses based on PET/MRI and PET/CT images were identical for all five patients. One discrepancy between PET/MRI and PET/CT was found in the assessment of the features in one patient. PET signal intensities and target-tobackground ratios were on average highest for PET/MRI. On PET/MRI, the location of infection based on FDG uptake could clearly be correlated with certain soft tissue structures (oedema, fluid collection, or muscle), which is paramount for surgical planning. Conclusions: In the presented cases, FDG PET/MRI led to the same diagnosis and provided at least the same diagnostic information as PET/CT. PET/MRI was able to provide additional soft-tissue information for the physician planning treatment. Because of this, we suggest that PET/MRI could be used for osteomyelitis diagnosis and treatment planning.
Journal of Bone and Joint Surgery, 2018
DOI to the publisher's website. • The final author version and the galley proof are versions of t... more DOI to the publisher's website. • The final author version and the galley proof are versions of the publication after peer review. • The final published version features the final layout of the paper including the volume, issue and page numbers. Link to publication General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. • Users may download and print one copy of any publication from the public portal for the purpose of private study or research. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal. If the publication is distributed under the terms of Article 25fa of the Dutch Copyright Act, indicated by the "Taverne" license above, please follow below link for the End User Agreement:
Journal of bone and joint infection, 2018
There is no generally established treatment algorithm for the management of surgical site infecti... more There is no generally established treatment algorithm for the management of surgical site infection (SSI) and non-union after instrumented spinal surgery. In contrast to infected hip- and knee- arthroplasties, the use of a local gentamicin impregnated carrier in spinal surgery has not been widely reported in literature. We studied 48 deep SSI and non-union patients after instrumented spine surgery, treated between 1999 and 2016. The minimum follow-up was 1.5 years. All infections were treated with a treatment-regimen consisting of systemic antibiotics and repetitive surgical debridement, supplemented with local gentamicin releasing carriers. We analysed the outcome of this treatment regimen with regard to healing of the infection, as well as patient- and surgery-characteristics of failed and successfully treated patients. 42 of the 48 (87.5%) patients showed successful resolution of the SSI without recurrence with a stable spine at the end of treatment. 36 patients' SSI were tre...
Advances in experimental medicine and biology, Jan 4, 2017
Osteomyelitis is an infectious process in bone that occasionally leads to bone destruction. Tradi... more Osteomyelitis is an infectious process in bone that occasionally leads to bone destruction. Traditionally, the surgical treatment procedure is performed in combination with systemic and local antibiotics as a two-stage procedure that uses autograft or allograft bone for filling of the cavitary defect. Bioactive glass (BAG-S53P4) is a bone substitute with proven antibacterial and bone bonding properties.One hundred and sixteen patients who had verified chronic osteomyelitis was treated using BAG-S53P4 as part of the treatment. Most of the patients had previously undergone numerous procedures, sometimes for decades. A register of patient data obtained from 11 centers from Finland, Italy, the Netherlands, Germany, Azerbaijan and Poland was set-up and continuously maintained at Helsinki University Central Hospital.The location of the osteomyelitis was mainly in the tibia followed by the femur and then the calcaneus. The median age of the patients was 48 years (15-87). The patients were ...
Frontiers in Bioengineering and Biotechnology, 2016
Background Bio-Active Glass (BAG) is a promising bone graft substitute for large bone defect reco... more Background Bio-Active Glass (BAG) is a promising bone graft substitute for large bone defect reconstruction because of its favourable osteoconductive, antibacterial and angiogenic properties. Potentially, it could also mechanically reinforce the defect, thus making it suitable for load-bearing defects. However, the mechanical properties of the reconstructive layer consisting of BAG/bone allograft mixtures are unknown. The goals of this study therefore were, first, to measure the mechanical properties of different BAG/bone graft mixtures and, second, to investigate to what extent such mixtures could reinforce distal tibial defects using micro-FE analysis and high-resolution CT scans. Materials and Methods Four different BAG/bone graft mixtures were impacted in a cylindrical holder, mechanically tested in confined compression and scanned with micro-CT. From these images, bone graft material and glass were segmented using two different threshold values. The interface between bone and BAG was modelled separately by dilating the glass phase. Micro-Finite-Element (FE) models of the composites were made using a Young9s modulus of 2.5 GPa for bone and 35 GPa for BAG. The Young9s modulus for the interface region was determined by fitting experimental and micro-FE results for the same specimens. (82 μm resolution) CT scans of a 9 mm region of the distal tibia of 3 subjects were used. Micro-FE models of this region were made to determine its stiffness in the original state, with a simulated cortical defect and after a mixture of BAG/bone was modelled in the defect. Results The confined compression tests showed a strong dependence of the modulus of the BAG/bone composite on the amount of BAG, ranging from 116.7 ± 18.2 to 654.2 ± 35.2 MPa. The micro-FE results could well reproduce these measured moduli, when using a stiffness of 25 MPa for the interface layer. The micro-FE analyses of the cortical defect demonstrated that the stiffness of the tibial segment would be reduced by 13 ± 3 % with the defect. Treatment with the BAG/bone composite could restore the stiffness to 101 ± 6 % of its original value. Discussion The experiments demonstrate that BAG/bone mixtures have a composition-dependent stiffness, in the range of that of trabecular bone, which can be well estimated from micro-FE analyses. Furthermore, the tibial micro-FE analyses demonstrate that these mixtures potentially can restore the stiffness of large bone defects at this site. Future development of the model may predict mechanical behaviour of BAG/bone mixtures patient specifically.
Acta orthopaedica, Jan 28, 2016
Background and purpose - A 2-stage revision is the most common treatment for late deep prosthesis... more Background and purpose - A 2-stage revision is the most common treatment for late deep prosthesis-related infections and in all cases of septic loosening. However, there is no consensus about the optimal interval between the 2 stages. Patients and methods - We retrospectively studied 120 deep infections of total hip (n = 95) and knee (n = 25) prostheses that had occurred over a period of 25 years. The mean follow-up time was 5 (2-20) years. All infections had been treated with extraction, 1 or more debridements with systemic antibiotics, and implantation of gentamicin-PMMA beads. There had been different time intervals between extraction and reimplantation: median 14 (11-47) days for short-term treatment with uninterrupted hospital stay, and 7 (3-22) months for long-term treatment with temporary discharge. We analyzed the outcome regarding resolution of the infection and clinical results. Results - 88% (105/120) of the infections healed, with no difference in healing rate between sh...
BioMed Research International, 2015
Nowadays, S53P4 bioactive glass is indicated as a bone graft substitute in various clinical appli... more Nowadays, S53P4 bioactive glass is indicated as a bone graft substitute in various clinical applications. This review provides an overview of the current published clinical results on indications such as craniofacial procedures, grafting of benign bone tumour defects, instrumental spondylodesis, and the treatment of osteomyelitis. Given the reported results that are based on examinations, such as clinical examinations by the surgeons, radiographs, CT, and MRI images, S53P4 bioactive glass may be beneficial in the various reported applications. Especially in craniofacial reconstructions like mastoid obliteration and orbital floor reconstructions, in grafting bone tumour defects, and in the treatment of osteomyelitis very promising results are obtained. Randomized clinical trials need to be performed in order to determine whether bioactive glass would be able to replace the current golden standard of autologous bone usage or with the use of antibiotic containing PMMA beads (in the cas...
Acta orthopaedica, Jan 12, 2015
Background and purpose - Aseptic loosening and infection are 2 of the most common causes of revis... more Background and purpose - Aseptic loosening and infection are 2 of the most common causes of revision of hip implants. Antibiotic prophylaxis reduces not only the rate of revision due to infection but also the rate of revision due to aseptic loosening. This suggests under-diagnosis of infections in patients with presumed aseptic loosening and indicates that current diagnostic tools are suboptimal. In a previous multicenter study on 176 patients undergoing revision of a total hip arthroplasty due to presumed aseptic loosening, optimized diagnostics revealed that 4-13% of the patients had a low-grade infection. These infections were not treated as such, and in the current follow-up study the effect on mid- to long-term implant survival was investigated. Patients and methods - Patients were sent a 2-part questionnaire. Part A requested information about possible re-revisions of their total hip arthroplasty. Part B consisted of 3 patient-related outcome measure questionnaires (EQ5D, Oxfo...
The Journal of Arthroplasty, 2016
Stress shielding remains a concern in total hip arthroplasty. The consequences of stress shieldin... more Stress shielding remains a concern in total hip arthroplasty. The consequences of stress shielding in hydroxyapatite-coated femoral component revisions were evaluated in a prospective cohort study. A total of 106 patients operated on by revision total hip arthroplasty were identified. Sixty-three patients were eligible for clinical and radiologic assessment of osseointegration, bone remodeling, and stress shielding. Five patients showed evidence of excessive stress shielding. One patient experienced a periprosthetic fracture. No adverse events occurred in the remaining patients with a low rate of thigh pain and reliable osseointegration. This is the only available study concerning mid- to long-term consequences of excessive stress shielding in hydroxyapatite-coated revision stems. We advocate surgeons using these stems to remain vigilant and be aware of possible stress shielding side effects.
Management of Periprosthetic Joint Infections (PJIs), 2017
Multiple difficulties occur during treatment of different orthopedic infections such as biofilm f... more Multiple difficulties occur during treatment of different orthopedic infections such as biofilm formation, osteonecrosis, destruction of bone matrix, and compromised soft tissues and vascularization. Biomaterials can be used to treat the infection and to solve the different treatment difficulties. These biomaterials can elicit local antibacterial therapy, which is necessary for optimal treatment of orthopedic infections. Furthermore, they can also be used as a bone defect filler after debridement surgery. Different types of biomaterials are developed: antibiotic-loaded collagen fleeces and ceramic or composite calcium-based bone graft substitutes as calcium sulfates, calcium phosphates, and hydroxyapatite. Another biomaterial used in treatment of these infections is bioactive glass. In this chapter, the properties of different biomaterials regarding treatment of infection are elucidated and the clinical results of these biomaterials in treatment of chronic osteomyelitis are discussed.
People interested in the research are advised to contact the author for the final version of the ... more People interested in the research are advised to contact the author for the final version of the publication, or visit the DOI to the publisher's website. • The final author version and the galley proof are versions of the publication after peer review. • The final published version features the final layout of the paper including the volume, issue and page numbers. Link to publication General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. • Users may download and print one copy of any publication from the public portal for the purpose of private study or research. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal. If the publication is distributed under the terms of Article 25fa of the Dutch Copyright Act, indicated by the "Taverne" license above, please follow below link for the End User Agreement:
Journal of Bone and Joint Infection, 2021
Introduction: Chronic osteomyelitis is a challenging condition in the orthopedic practice and tra... more Introduction: Chronic osteomyelitis is a challenging condition in the orthopedic practice and traditionally treated using local and systemic antibiotics in a two-stage surgical procedure. With the introduction of the antimicrobial biomaterial S53P4 bioactive glass (Bonalive ®), chronic osteomyelitis can be treated in a one-stage procedure. This study evaluated the mid-term clinical results of patients treated with S53P4 bioactive glass for long bone chronic osteomyelitis. Methods: In this prospective multi-center study, patients from two different university medical centers in the Netherlands were included. One-stage treatment consisted of debridement surgery, implantation of S53P4 bioactive glass, and treatment with culture-based systemic antibiotics. If required, wound closure by a plastic surgeon was performed. The primary outcome was the eradication of infection, and a secondary statistical analysis was performed on probable risk factors for treatment failure. Results: In total, 78 patients with chronic cavitary long bone osteomyelitis were included. Follow-up was at least 12 months (mean 46; standard deviation, SD, 20), and 69 patients were treated in a one-stage procedure. Overall infection eradication was 85 %, and 1-year infection-free survival was 89 %. Primary closure versus local/muscular flap coverage is the only risk factor for treatment failure. Conclusion: With 85 % eradication of infection, S53P4 bioactive glass is an effective biomaterial in the treatment of chronic osteomyelitis in a one-stage procedure. A major risk factor for treatment failure is the necessity for local/free muscle flap coverage. These results confirm earlier published data, and together with the fundamentally different antimicrobial pathways without antibiotic resistance, S53P4 bioactive glass is a recommendable biomaterial for chronic osteomyelitis treatment and might be beneficial over other biomaterials. 1 Introduction Chronic osteomyelitis is a bacterial infection of the bone and bone marrow and is one of the biggest clinical challenges in current orthopedic practice. It is predominantly posttraumatic and is often seen after orthopedic (open) fracture surgery but can also be caused by a hematogenous spread or direct postoperative colonization (Lazzarini et al., 2004; Lew and Waldvogel, 2004). Treatment of these infections is difficult because the infected bone and the surrounding tissues are often devitalized (i.e., dead bone sequesters) and poorly vascularized due to the (mostly) long-term present infection. In combination with risk factors as smoking, peripheral vascular disease, diabetes or malnutrition, patients often need multiple surgical procedures where the risks of reinfection
Journal of Orthopaedic Research, 2020
Chronic osteomyelitis has always been a therapeutic challenge for patient and surgeon due to the ... more Chronic osteomyelitis has always been a therapeutic challenge for patient and surgeon due to the specific problems related with bone infection and bacterial biofilm eradication. Other than being the cause of infection or facilitating spread or persistence of infection, biomaterials are also becoming a tool in the treatment of infection. Certain novel biomaterials have unique and ideal properties that render them perfectly suited to combat infection and are therefore used more and more in the treatment of chronic bone infections. In case of infection treatment, there is still debate whether these properties should be focused on bone regeneration and/or their antimicrobial properties. These properties will be of even greater importance with the challenge of emerging antimicrobial resistance. This review highlights indications for use and specific material properties of some commonly used contemporary biomaterials for this indication as well as clinical experience and a literature overview. This article is protected by copyright. All rights reserved.
SA Orthopaedic Journal, 2018
Aim: Chronic osteomyelitis is still a difficult problem to treat in the developed world, but even... more Aim: Chronic osteomyelitis is still a difficult problem to treat in the developed world, but even more so in low-and middle-income countries. Contemporary treatment options result in satisfying outcomes in a setting with abundant resources, but the question is whether these treatment options can be translated to other, less supported health care systems and if they obtain the same results. Methods: Eighteen patients with established chronic osteomyelitis (eight type III, ten type IV) were prospectively enrolled and treated in a one-stage procedure with radical debridement and dead space management using bioactive glass S53P4 granules, together with adjuvant antibiotic therapy. Results: Thirteen patients were assessed at 24 months. Infection control was achieved in five patients (38%). Eight patients (61.5%) had persistence or recurrence of infection. Loss to follow-up was substantial (five patients, 28%). Conclusion: Due to specific challenges treating chronic osteomyelitis in low-and middle-income countries, contemporary treatment options cannot be 'copy-pasted' with the same results in these settings.
Materials, 2019
Bioactive glass (BAG) granules (S53P4) have shown good clinical results in one-stage treatment of... more Bioactive glass (BAG) granules (S53P4) have shown good clinical results in one-stage treatment of osteomyelitis. During this treatment, a cortical window is created, and infected bone is debrided, which results in large defects that affect the mechanical properties of the bone. This study aimed to evaluate the role of BAG granules in load-bearing bone defect grafting. First, the influence of the geometry of the cortical window on the bone bending stiffness and estimated failure moments was evaluated using micro finite element analysis (µFE). This resulted in significant differences between the variations in width and length. In addition, µFE analysis showed that BAG granules contribute to bearing loads in simulated compression of a tibia with a defect grafted with BAG and a BAG and bone morsel mixture. These mixtures potentially can unload the cortical bone that is weakened by a large defect directly after the operation by up to approximately 25%, but only in case of optimal load tr...
Materials, 2019
This study was set up to evaluate the costs of a one-stage treatment of chronic osteomyelitis usi... more This study was set up to evaluate the costs of a one-stage treatment of chronic osteomyelitis using bioactive glass S53P4 versus a two-stage treatment using gentamicin-loaded PMMA beads. Furthermore, a cost-effectiveness analysis was performed from a hospital’s perspective together with the evaluation of clinical outcome. A treatment group (n = 25) receiving one-stage surgery with bioactive glass was retrospectively compared with a two-stage control group (n = 25). An assessment was made of all costs included from first outpatient visit until one year after treatment. Bootstrap simulation and sensitivity analyses were performed. The primary endpoint was cost-effectiveness with clinical outcome as the secondary endpoint. The base case analyses shows dominance of the one-stage treatment with bioactive glass S53P4 due to lower costs and a better clinical outcome. Sensitivity analyses confirm these findings. This study is the first in its kind to show one-stage treatment of chronic oste...
European Journal of Hybrid Imaging, 2019
Background: Magnetic resonance imaging (MRI) and 2-[18F]-fluoro-2-deoxy-Dglucose (FDG) positron e... more Background: Magnetic resonance imaging (MRI) and 2-[18F]-fluoro-2-deoxy-Dglucose (FDG) positron emission tomography paired with computed tomography (PET/CT) are two commonly used imaging modalities in the complicated diagnostic workup of osteomyelitis. Diagnosis using these modalities relies on, respectively, anatomical (MRI) and metabolic (PET) signs. With hybrid PET/MRI being recently available, our goal is to qualitatively compare hybrid FDG PET/MRI to FDG PET/CT in the diagnosis and operative planning of chronic osteomyelitis. Methods: Five patients with suspected chronic osteomyelitis in an extremity underwent an 18 F-FDG single-injection/dual-imaging protocol with hybrid PET/CT and hybrid PET/MR. Images and clinical features were evaluated using a standardized assessment method. Standardized uptake value (SUV) measurements were performed on all images. Concordant and discordant findings between PET/MRI and PET/CT were analysed. Results: The consensus diagnoses based on PET/MRI and PET/CT images were identical for all five patients. One discrepancy between PET/MRI and PET/CT was found in the assessment of the features in one patient. PET signal intensities and target-tobackground ratios were on average highest for PET/MRI. On PET/MRI, the location of infection based on FDG uptake could clearly be correlated with certain soft tissue structures (oedema, fluid collection, or muscle), which is paramount for surgical planning. Conclusions: In the presented cases, FDG PET/MRI led to the same diagnosis and provided at least the same diagnostic information as PET/CT. PET/MRI was able to provide additional soft-tissue information for the physician planning treatment. Because of this, we suggest that PET/MRI could be used for osteomyelitis diagnosis and treatment planning.
Journal of Bone and Joint Surgery, 2018
DOI to the publisher's website. • The final author version and the galley proof are versions of t... more DOI to the publisher's website. • The final author version and the galley proof are versions of the publication after peer review. • The final published version features the final layout of the paper including the volume, issue and page numbers. Link to publication General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. • Users may download and print one copy of any publication from the public portal for the purpose of private study or research. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal. If the publication is distributed under the terms of Article 25fa of the Dutch Copyright Act, indicated by the "Taverne" license above, please follow below link for the End User Agreement:
Journal of bone and joint infection, 2018
There is no generally established treatment algorithm for the management of surgical site infecti... more There is no generally established treatment algorithm for the management of surgical site infection (SSI) and non-union after instrumented spinal surgery. In contrast to infected hip- and knee- arthroplasties, the use of a local gentamicin impregnated carrier in spinal surgery has not been widely reported in literature. We studied 48 deep SSI and non-union patients after instrumented spine surgery, treated between 1999 and 2016. The minimum follow-up was 1.5 years. All infections were treated with a treatment-regimen consisting of systemic antibiotics and repetitive surgical debridement, supplemented with local gentamicin releasing carriers. We analysed the outcome of this treatment regimen with regard to healing of the infection, as well as patient- and surgery-characteristics of failed and successfully treated patients. 42 of the 48 (87.5%) patients showed successful resolution of the SSI without recurrence with a stable spine at the end of treatment. 36 patients' SSI were tre...
Advances in experimental medicine and biology, Jan 4, 2017
Osteomyelitis is an infectious process in bone that occasionally leads to bone destruction. Tradi... more Osteomyelitis is an infectious process in bone that occasionally leads to bone destruction. Traditionally, the surgical treatment procedure is performed in combination with systemic and local antibiotics as a two-stage procedure that uses autograft or allograft bone for filling of the cavitary defect. Bioactive glass (BAG-S53P4) is a bone substitute with proven antibacterial and bone bonding properties.One hundred and sixteen patients who had verified chronic osteomyelitis was treated using BAG-S53P4 as part of the treatment. Most of the patients had previously undergone numerous procedures, sometimes for decades. A register of patient data obtained from 11 centers from Finland, Italy, the Netherlands, Germany, Azerbaijan and Poland was set-up and continuously maintained at Helsinki University Central Hospital.The location of the osteomyelitis was mainly in the tibia followed by the femur and then the calcaneus. The median age of the patients was 48 years (15-87). The patients were ...
Frontiers in Bioengineering and Biotechnology, 2016
Background Bio-Active Glass (BAG) is a promising bone graft substitute for large bone defect reco... more Background Bio-Active Glass (BAG) is a promising bone graft substitute for large bone defect reconstruction because of its favourable osteoconductive, antibacterial and angiogenic properties. Potentially, it could also mechanically reinforce the defect, thus making it suitable for load-bearing defects. However, the mechanical properties of the reconstructive layer consisting of BAG/bone allograft mixtures are unknown. The goals of this study therefore were, first, to measure the mechanical properties of different BAG/bone graft mixtures and, second, to investigate to what extent such mixtures could reinforce distal tibial defects using micro-FE analysis and high-resolution CT scans. Materials and Methods Four different BAG/bone graft mixtures were impacted in a cylindrical holder, mechanically tested in confined compression and scanned with micro-CT. From these images, bone graft material and glass were segmented using two different threshold values. The interface between bone and BAG was modelled separately by dilating the glass phase. Micro-Finite-Element (FE) models of the composites were made using a Young9s modulus of 2.5 GPa for bone and 35 GPa for BAG. The Young9s modulus for the interface region was determined by fitting experimental and micro-FE results for the same specimens. (82 μm resolution) CT scans of a 9 mm region of the distal tibia of 3 subjects were used. Micro-FE models of this region were made to determine its stiffness in the original state, with a simulated cortical defect and after a mixture of BAG/bone was modelled in the defect. Results The confined compression tests showed a strong dependence of the modulus of the BAG/bone composite on the amount of BAG, ranging from 116.7 ± 18.2 to 654.2 ± 35.2 MPa. The micro-FE results could well reproduce these measured moduli, when using a stiffness of 25 MPa for the interface layer. The micro-FE analyses of the cortical defect demonstrated that the stiffness of the tibial segment would be reduced by 13 ± 3 % with the defect. Treatment with the BAG/bone composite could restore the stiffness to 101 ± 6 % of its original value. Discussion The experiments demonstrate that BAG/bone mixtures have a composition-dependent stiffness, in the range of that of trabecular bone, which can be well estimated from micro-FE analyses. Furthermore, the tibial micro-FE analyses demonstrate that these mixtures potentially can restore the stiffness of large bone defects at this site. Future development of the model may predict mechanical behaviour of BAG/bone mixtures patient specifically.
Acta orthopaedica, Jan 28, 2016
Background and purpose - A 2-stage revision is the most common treatment for late deep prosthesis... more Background and purpose - A 2-stage revision is the most common treatment for late deep prosthesis-related infections and in all cases of septic loosening. However, there is no consensus about the optimal interval between the 2 stages. Patients and methods - We retrospectively studied 120 deep infections of total hip (n = 95) and knee (n = 25) prostheses that had occurred over a period of 25 years. The mean follow-up time was 5 (2-20) years. All infections had been treated with extraction, 1 or more debridements with systemic antibiotics, and implantation of gentamicin-PMMA beads. There had been different time intervals between extraction and reimplantation: median 14 (11-47) days for short-term treatment with uninterrupted hospital stay, and 7 (3-22) months for long-term treatment with temporary discharge. We analyzed the outcome regarding resolution of the infection and clinical results. Results - 88% (105/120) of the infections healed, with no difference in healing rate between sh...
BioMed Research International, 2015
Nowadays, S53P4 bioactive glass is indicated as a bone graft substitute in various clinical appli... more Nowadays, S53P4 bioactive glass is indicated as a bone graft substitute in various clinical applications. This review provides an overview of the current published clinical results on indications such as craniofacial procedures, grafting of benign bone tumour defects, instrumental spondylodesis, and the treatment of osteomyelitis. Given the reported results that are based on examinations, such as clinical examinations by the surgeons, radiographs, CT, and MRI images, S53P4 bioactive glass may be beneficial in the various reported applications. Especially in craniofacial reconstructions like mastoid obliteration and orbital floor reconstructions, in grafting bone tumour defects, and in the treatment of osteomyelitis very promising results are obtained. Randomized clinical trials need to be performed in order to determine whether bioactive glass would be able to replace the current golden standard of autologous bone usage or with the use of antibiotic containing PMMA beads (in the cas...
Acta orthopaedica, Jan 12, 2015
Background and purpose - Aseptic loosening and infection are 2 of the most common causes of revis... more Background and purpose - Aseptic loosening and infection are 2 of the most common causes of revision of hip implants. Antibiotic prophylaxis reduces not only the rate of revision due to infection but also the rate of revision due to aseptic loosening. This suggests under-diagnosis of infections in patients with presumed aseptic loosening and indicates that current diagnostic tools are suboptimal. In a previous multicenter study on 176 patients undergoing revision of a total hip arthroplasty due to presumed aseptic loosening, optimized diagnostics revealed that 4-13% of the patients had a low-grade infection. These infections were not treated as such, and in the current follow-up study the effect on mid- to long-term implant survival was investigated. Patients and methods - Patients were sent a 2-part questionnaire. Part A requested information about possible re-revisions of their total hip arthroplasty. Part B consisted of 3 patient-related outcome measure questionnaires (EQ5D, Oxfo...
The Journal of Arthroplasty, 2016
Stress shielding remains a concern in total hip arthroplasty. The consequences of stress shieldin... more Stress shielding remains a concern in total hip arthroplasty. The consequences of stress shielding in hydroxyapatite-coated femoral component revisions were evaluated in a prospective cohort study. A total of 106 patients operated on by revision total hip arthroplasty were identified. Sixty-three patients were eligible for clinical and radiologic assessment of osseointegration, bone remodeling, and stress shielding. Five patients showed evidence of excessive stress shielding. One patient experienced a periprosthetic fracture. No adverse events occurred in the remaining patients with a low rate of thigh pain and reliable osseointegration. This is the only available study concerning mid- to long-term consequences of excessive stress shielding in hydroxyapatite-coated revision stems. We advocate surgeons using these stems to remain vigilant and be aware of possible stress shielding side effects.