RESUMO
INTRODUCTION: In the staged management of tibial pilon fractures, overlap between definitive internal fixation and external fixation pin sites has been investigated as a risk factor for infection with equivocal conclusions. Our aim was to determine if overlap or proximity of definitive internal fixation to external fixation pin sites influences the risk of deep infection. PATIENTS AND METHODS: We reviewed 280 AO/OTA 43B or 43C type distal tibia fractures in 277 patients at two level-one trauma centers. Patients underwent staged management using early temporizing external fixation followed by definitive open reduction and plate fixation. Primary outcome was the association between pin site overlap and the development of deep infection. Secondary outcome was the relationship between development of deep infection and the distance from pin site to definitive fixation. RESULTS: The average duration between external fixation and definitive internal fixation was 14 days. 24% of fractures developed deep infection requiring surgical intervention. There was no association between pin site overlap and the development of deep infection (pâ¯=â¯0.18). There was no relationship between infection and the distance between proximal plate extent and pin site (pâ¯=â¯0.13). DISCUSSION: We identified no association between pin site overlap and the development of deep infection. We suggest that temporizing external fixation pins should be placed so as to obtain optimal stability of the construct with lesser emphasis on aiming to be absolutely outside the zone of future fixation. LEVEL OF EVIDENCE: Level III Therapeutic Retrospective Comparative study.
Assuntos
Traumatismos do Tornozelo/cirurgia , Fixadores Externos/microbiologia , Fixação de Fratura/métodos , Fraturas Expostas/cirurgia , Infecção da Ferida Cirúrgica/microbiologia , Fraturas da Tíbia/cirurgia , Cicatrização/fisiologia , Adulto , Traumatismos do Tornozelo/microbiologia , Traumatismos do Tornozelo/patologia , Pinos Ortopédicos/microbiologia , Desbridamento/métodos , Feminino , Fixação de Fratura/efeitos adversos , Fixação de Fratura/instrumentação , Fraturas Expostas/microbiologia , Fraturas Expostas/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Infecção da Ferida Cirúrgica/prevenção & controle , Fraturas da Tíbia/microbiologia , Fraturas da Tíbia/patologia , Resultado do TratamentoRESUMO
BACKGROUND: Unstable pelvic fractures are typically caused by high-impact trauma. Early stabilization is required to prevent further neurological or visceral injury, haemorrhage, reduce pain, infection and long-term deformity and disability. The aim was to review the optimal external fixation techniques and management for unstable pelvic fractures. METHODS: A total of 28 studies were identified from the initial database search. Seventeen studies met our inclusion criteria - eight prospective cohorts, four retrospective cohorts and five in vitro studies. This equated to 539 patients and 38 cadaveric (in vitro) models. RESULTS: Type B and double vertical fractures have less re-displacement (43.7% and 68.2% <5 mm, respectively) than Type C fractures (55.7% >15 mm) regardless of pin placement. Greater than 50% experience a complication with the most common being pin site infection (36%) and a trend towards increased infection with increasing pins was seen. Most can be managed with antibiotics alone (93%). A minimum time of 6-8 weeks in frame was required for definitive management of all fractures. CONCLUSION: This review supports the use of supra-acetabular pins over iliac crest pins to decrease re-displacement, the least number of pins for the shortest amount of time and the largest size pin where possible. Type B fractures will generally have a better outcome than Type C fractures. Definitive management in a frame should be at least 8 weeks. Further studies directly comparing iliac crest and supra-acetabular pin placement are recommended.
Assuntos
Pinos Ortopédicos/efeitos adversos , Fixadores Externos/efeitos adversos , Fixação de Fratura/métodos , Fraturas Ósseas/cirurgia , Ossos Pélvicos/lesões , Acetábulo/cirurgia , Fenômenos Biomecânicos/fisiologia , Pinos Ortopédicos/microbiologia , Cadáver , Fraturas Ósseas/classificação , Humanos , Ílio/cirurgia , Ensaios Clínicos Controlados não Aleatórios como Assunto , Estudos Observacionais como Assunto , Ossos Pélvicos/patologia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/microbiologia , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos RetrospectivosRESUMO
BACKGROUND: The aim of this study is to establish the bacterial epidemiology of chronic osteoarticular infections in adults, to study the susceptibility of the isolated strains to antibiotics and to demonstrate the influence of osteosynthesis material thereon. PATIENTS AND METHODS: This is a retrospective study of 78 months, from January 2006 to June 2012, providing bacteriological samples from patients with osteitis and osteoarthritis in the Mohammed V military teaching hospital of Rabat. Isolation and identification of bacteria were made by bacteriological classical techniques. The antimicrobial susceptibility testing of the isolates was performed by disk diffusion agar method, as recommended by the Committee of the susceptibility of the French Society for Microbiology (CA-SFM). RESULTS: We collected 234 cases, 53% (n = 124) of patients without osteosynthesis material (group A) and 47% (n = 110) patients with osteosynthesis material (group B).We isolated 371 bacteria which 51.49 (n = 191) in group A and 48.51% (n = 180) in group B. Gram-positive cocci were the most frequent (n = 234), followed by the Gram-negative bacilli (n = 114) and the Gram-positive bacilli (n = 19). Our study shows that the rate of resistance to antibiotics in strains obtained from patients with osteosynthesis material is higher compared to those obtained from patients without osteosynthesis material. CONCLUSIONS: Chronic OA infection in adults is difficult to diagnose and treat. Its good management must be multidisciplinary.
Assuntos
Doenças Ósseas Infecciosas/microbiologia , Farmacorresistência Bacteriana , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Positivas/isolamento & purificação , Fixadores Internos/microbiologia , Osteíte/microbiologia , Osteoartrite/microbiologia , Adulto , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Doenças Ósseas Infecciosas/tratamento farmacológico , Doenças Ósseas Infecciosas/epidemiologia , Pinos Ortopédicos/microbiologia , Placas Ósseas/microbiologia , Parafusos Ósseos/microbiologia , Doença Crônica , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Humanos , Osteíte/tratamento farmacológico , Osteíte/epidemiologia , Osteoartrite/tratamento farmacológico , Osteoartrite/epidemiologia , Estudos RetrospectivosRESUMO
Current strategies in implant technology are directed to generate bioactive implants that are capable to activate the regenerative potential of the surrounding tissue. On the other hand, implant-related infections are a common problem in orthopaedic trauma patients. To meet both challenges, i.e. to generate a bone implant with regenerative and antimicrobial characteristics, we tested the use of copper coated nails for surgical fixation in a rabbit model. Copper acetate was galvanically deposited with a copper load of 1 µg/mm2 onto a porous oxide layer of Ti6Al4V nails, which were used for the fixation of a tibia fracture, inoculated with bacteria. After implantation of the nail the concentration of copper ions did not increase in blood which indicates that copper released from the implant was locally restricted to the fracture site. After four weeks, analyses of the extracted implants revealed a distinct antimicrobial effect of copper, because copper completely prevented both a weak adhesion and firm attachment of biofilm-forming bacteria on the titanium implant. To evaluate fracture healing, radiographic examination demonstrated an increased callus index in animals with copper coated nails. This result indicates a stimulated bone formation by releasing copper ions. We conclude that the use of implants with a defined load of copper ions enables both prevention of bacterial infection and the stimulation of regenerative processes.
Assuntos
Antibacterianos/uso terapêutico , Pinos Ortopédicos , Materiais Revestidos Biocompatíveis/uso terapêutico , Cobre/uso terapêutico , Osteogênese/efeitos dos fármacos , Fraturas da Tíbia/cirurgia , Titânio/uso terapêutico , Ligas , Animais , Antibacterianos/química , Pinos Ortopédicos/microbiologia , Materiais Revestidos Biocompatíveis/química , Cobre/química , Feminino , Consolidação da Fratura/efeitos dos fármacos , Coelhos , Infecções Estafilocócicas/complicações , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/efeitos dos fármacos , Fraturas da Tíbia/complicações , Fraturas da Tíbia/tratamento farmacológico , Fraturas da Tíbia/microbiologia , Titânio/químicaRESUMO
BACKGROUND: There has been a great increase in the use of navigation technology in joint arthroplasty. In most types of navigation-assisted surgery, several temporary navigation pins are placed in the patient. Goals of this study are (1) to identify complications and (2) risk factors associated with placement of these pins. METHODS: This is a retrospective cohort study of all navigation-assisted hip and knee arthroplasty performed a single institution over a 3-year period. Records were reviewed and outcome measures were tabulated in a database. Complications included in the database were pin site infection, deep prosthetic joint infection, neurologic injury, vascular injury, and fracture through a pin site. RESULTS: A total of 3136 pin sites in 839 patients were included in the study. Five pin site complications were reported with a complication rate of 0.16% per pin site and 0.60% per patient. The complications-per-procedure were slightly higher for unicondylar knee arthroplasty (0.64%) compared with patellofemoral arthroplasty (0%) and total hip arthroplasty (0.46%), but not statistically significant. There were three infections, one neuropraxia, and one suture abscess. No periprosthetic fractures through a pin site were reported. All complications were resolved with nonoperative treatment. The infections required oral antibiotics, and were associated with transcortical drilling in two cases and juxtacortical drilling in the third. CONCLUSION: Pins required for navigation-assisted arthroplasty have a low complication rate. Transcortical or juxtacortical drilling may be a risk factor for pin site infection; future studies should be directed at quantifying this effect.
Assuntos
Artroplastia de Quadril/efeitos adversos , Artroplastia do Joelho/efeitos adversos , Pinos Ortopédicos/efeitos adversos , Infecções Relacionadas à Prótese/etiologia , Cirurgia Assistida por Computador/efeitos adversos , Adulto , Idoso , Artroplastia de Quadril/métodos , Artroplastia do Joelho/métodos , Pinos Ortopédicos/microbiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infecções Relacionadas à Prótese/diagnóstico por imagem , Infecções Relacionadas à Prótese/terapia , Estudos Retrospectivos , Fatores de Risco , Cirurgia Assistida por Computador/métodosRESUMO
OBJECTIVE: To evaluate the in vivo anti-staphylococcal bactericidal activity of farnesol on Ti6Al4V surfaces. MATERIAL AND METHODS: An experimental model of infection in biomaterials was developed by inoculation of Staphylococcus aureus ATCC 29213 into the canal of both femurs of 15 Wistar rats. A Ti6Al4V pin impregnated with 30mM of farnesol was inserted into study femur, and a Ti6Al4V control was inserted into the control femur. To evaluate the bactericidal efficacy, a comparison was made between the median of the colony forming units recovered after inoculation in the study group and the control group for different times of euthanasia and inoculum size. RESULTS: The median expressed as Log10 CFU counts obtained with farnesol titanium pin was 4.26, and in control group, it was 4.86, which was statistically significant (P=.001) on applying the Student t test for related samples. The median reduction obtained in farnesol pins relative to the control was 74%. CONCLUSIONS: Treatment with farnesol 30mM on Ti6Al4V pins appears to decrease the rate of colonisation by Staphylococcus aureus.
Assuntos
Antibacterianos/administração & dosagem , Pinos Ortopédicos/efeitos adversos , Farneseno Álcool/administração & dosagem , Infecções Relacionadas à Prótese/prevenção & controle , Infecções Estafilocócicas/prevenção & controle , Staphylococcus aureus/isolamento & purificação , Titânio , Ligas , Animais , Antibacterianos/uso terapêutico , Pinos Ortopédicos/microbiologia , Contagem de Colônia Microbiana , Farneseno Álcool/uso terapêutico , Fêmur/microbiologia , Fêmur/cirurgia , Masculino , Infecções Relacionadas à Prótese/diagnóstico , Distribuição Aleatória , Ratos , Ratos Wistar , Infecções Estafilocócicas/diagnóstico , Infecções Estafilocócicas/etiologiaRESUMO
BACKGROUND: Despite improvement in operative techniques and antibiotic therapy, septic complications still occur in open fractures. We developed silver ion containing ceramic nano powder for implant coating to provide not only biocompatibility but also antibacterial activity to the orthopaedic implants. QUESTIONS/PURPOSES: We hypothesised silver ion doped calcium phosphate based ceramic nano-powder coated titanium nails may prevents bacterial colonisation and infection in open fractures as compared with uncoated nails. METHODS: 33 rabbits divided into three groups. In the first group uncoated, in the second group hydroxyapatite coated, and in the third group silver doped hydroxyapatite coated titanium nails were inserted left femurs of animals from knee regions with retrograde fashion. Before implantation of nails 50 µl solution containing 10(6)CFU/ml methicillin resistance Staphylococcus aureus (MRSA) injected intramedullary canal. Rabbits were monitored for 10 weeks. Blood was taken from rabbits before surgery and on 2nd, 6th and 10th weeks. Blood was analysed for biochemical parameters, blood count, C-reactive protein and silver levels. At the end of the 10 weeks animals were sacrificed and rods were extracted in a sterile fashion. Swab cultures were taken from intramedullary canal. Bacteria on titanium rods were counted. Liver, heart, spleen, kidney and central nervous tissues samples were taken for determining silver levels. Histopathological evaluation of bone surrounding implants was also performed. RESULTS: No significant difference was detected between the groups from hematologic, biochemical, and toxicological aspect. Microbiological results showed that less bacterial growth was detected with the use of silver doped ceramic coated implants compared to the other two groups (p=0.003). Accumulation of silver was not detected. No cellular inflammation was observed around the silver coated prostheses. No toxic effect of silver on bone cells was seen. CONCLUSION: Silver ion doped calcium phosphate based ceramic nano powder coating to orthopaedic implants may prevents bacterial colonisation and infection in open fractures compared with those for implants without any coating.
Assuntos
Antibacterianos/farmacologia , Pinos Ortopédicos , Materiais Revestidos Biocompatíveis/farmacologia , Fraturas Expostas/patologia , Infecções Relacionadas à Prótese/patologia , Infecções Estafilocócicas/patologia , Animais , Pinos Ortopédicos/microbiologia , Fosfatos de Cálcio , Modelos Animais de Doenças , Masculino , Teste de Materiais , Nanopartículas Metálicas/microbiologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Nanomedicina , Coelhos , Prata , TitânioRESUMO
The local mechanical environment at a fracture is known to influence biological factors such as callus formation, immune cell recruitment and susceptibility to infection. Infection models incorporating a fracture are therefore required to evaluate prevention and treatment of infection after osteosynthesis. The aim of this study was to create humane, standardised and repeatable preclinical models of implant-related bone infection after osteosynthesis in the rabbit humerus. Custom-designed interlocked intramedullary nails and commercially available locking plates were subjected to biomechanical evaluation in cadaveric rabbit humeri; a 10-week in vivo healing study; a dose response study with Staphylococcus aureus over 4 weeks; and finally, a long-term infection of 10 weeks in the plate model.Outcome measures included biomechanical testing, radiography, histology, haematology and quantitative bacteriology. Both implants offered similar biomechanical stability in cadaveric bones, and when applied in the in vivo study, resulted in complete radiographic and histological healing and osteotomy closure within 10-weeks. As expected in the infection study, higher bacterial doses led to an increasing infection rate. In both infected groups, there was a complete lack of osteotomy closure at 4 weeks. C-reactive protein (CRP), lymphocyte: granulocyte ratio and weight loss were increased in infected animals receiving IM nails in comparison with non-inoculated equivalents, although this was less evident in the plate group. In the 10-week infection group, healing does not occur in the plated rabbits. We have successfully developed a rabbit model that is suitable for further studies, particularly those looking into preventative strategies for post-traumatic implant-related osteomyelitis.
Assuntos
Pinos Ortopédicos/microbiologia , Fixação Interna de Fraturas , Consolidação da Fratura/fisiologia , Fraturas Ósseas/cirurgia , Osteomielite/cirurgia , Infecções Estafilocócicas , Staphylococcus aureus , Animais , Modelos Animais de Doenças , Fixação Interna de Fraturas/métodos , CoelhosRESUMO
A new device for local delivery of antibiotics is presented, with potential use as a drug-eluting fixation pin for orthopedic applications. The implant consists of a stainless steel hollow tubular reservoir packed with the desired antibiotic. Release takes place through several orifices previously drilled in the reservoir wall, a process that does not compromise the mechanical properties required for the implant. Depending on the antibiotic chosen and the number of orifices, the release profile can be tailored from a rapid release of the load (ca. 20h) to a combination of rapid initial release and slower, sustained release for a longer period of time (ca. 200h). An excellent bactericidal action is obtained, with 4-log reductions achieved in as little as 2h, and total bacterial eradication in 8h using 6-pinholed implants filled with cefazolin.
Assuntos
Antibacterianos/administração & dosagem , Pinos Ortopédicos/microbiologia , Cefazolina/administração & dosagem , Infecções Relacionadas à Prótese/tratamento farmacológico , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/farmacologia , Pinos Ortopédicos/efeitos adversos , Cefazolina/química , Cefazolina/farmacologia , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacologia , Difusão , Composição de Medicamentos , Implantes de Medicamento , Liberação Controlada de Fármacos , Cinética , Fenômenos Mecânicos , Pós , Infecções Relacionadas à Prótese/microbiologia , Solubilidade , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/crescimento & desenvolvimento , AçoRESUMO
Pin site infection is a common complication after fracture fixation and bone lengthening, and daily pin site care is recommended. Weather is a strong environmental factor of infection, but few articles studied the issue of weather and pin site infection. We performed a prospective comparative study of 61 children with supracondylar humeral fractures treated by closed reduction and percutaneous pinning. The patients were divided into high-temperature season or low-temperature season by the months they received surgery. The patients within each season were further allocated to 2 groups by the different postoperative pin site care methods of daily care or noncare. The infection rate per patient was significantly higher in the high-temperature season compared to low-temperature season (45% versus 19%, P = 0.045). In the high-temperature season, the infection rate per patient was significantly higher in the daily care group versus the noncare group (70% versus 20%, P = 0.001). In the low-temperature season, the infection rate per patient was not significantly different in the daily care group versus the noncare group (10% versus 27.3%, P = 0.33). We recommend that careful monitoring of infection signs, rather than pin site cleaning, would be appropriate in the treatment of pediatric supracondylar humeral fractures, especially during the summer months.
Assuntos
Pinos Ortopédicos/microbiologia , Fixação de Fratura/efeitos adversos , Fraturas do Úmero/fisiopatologia , Infecções/fisiopatologia , Criança , Pré-Escolar , Feminino , Humanos , Fraturas do Úmero/complicações , Fraturas do Úmero/microbiologia , Infecções/etiologia , Infecções/microbiologia , Masculino , Cuidados Pós-Operatórios , Estações do Ano , Temperatura , Resultado do TratamentoRESUMO
Antibiotic prophylaxis is standard for patients undergoing surgical procedures, yet despite the wide use of antibiotics, breakthrough infections still occur. In the setting of total joint arthroplasty, such infections can be devastating. Recent findings have shown that synovial fluid causes marked staphylococcal aggregation, which can confer antibiotic insensitivity. We therefore asked in this study whether clinical samples of synovial fluid that contain preoperative prophylactic antibiotics can successfully eradicate a bacterial challenge by pertinent bacterial species. This study demonstrates that preoperative prophylaxis with cefazolin results in high antibiotic levels. Furthermore, we show that even with antibiotic concentrations that far exceed the expected bactericidal levels, Staphylococcus aureus bacteria added to the synovial fluid samples are not eradicated and are able to colonize model implant surfaces, i.e., titanium pins. Based on these studies, we suggest that current prophylactic antibiotic choices, despite high penetration into the synovial fluid, may need to be reexamined.
Assuntos
Antibacterianos/farmacologia , Antibioticoprofilaxia , Biofilmes/efeitos dos fármacos , Cefazolina/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Líquido Sinovial/microbiologia , Ligas , Aderência Bacteriana , Pinos Ortopédicos/microbiologia , Farmacorresistência Bacteriana , Humanos , Testes de Sensibilidade Microbiana , TitânioRESUMO
One of the major problems in orthopedic surgery is infection associated with implantation. The treatment is a very difficult and long-term process. A solution to this issue can be the use of implants which additionally constitute an antibiotic carrier preventing the development of an infection. Prototypes of biodegradable intramedullary nails made of three different composites with a poly(L-lactide) matrix were designed. The nails served as gentamicin sulfate (GS) carrier - an antibiotic commonly used in the treatment of osteomyelitis. The matrix was reinforced with carbon fibers (CF), alginate fibers (Alg) and magnesium alloy wires (Mg), as well as modified with bioactive particles of tricalcium phosphate (TCP) in various systems. In this way, novel, multi-phase and multifunctional degradable intramedullary nails were obtained. The tests demonstrated strong dependence between the type of the modifying phase introduced into the composite, and the rate of drug release. Introduction of gentamicin into the nail structure strengthened and prolonged antibacterial activity of the nails.
Assuntos
Antibacterianos/química , Materiais Biocompatíveis/química , Pinos Ortopédicos , Gentamicinas/química , Poliésteres/química , Alginatos/química , Ligas/química , Antibacterianos/administração & dosagem , Antibacterianos/farmacologia , Pinos Ortopédicos/microbiologia , Fosfatos de Cálcio/química , Gentamicinas/administração & dosagem , Gentamicinas/farmacologia , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Humanos , Microscopia Eletrônica de Varredura , Osteomielite/tratamento farmacológico , Osteomielite/prevenção & controle , Próteses e Implantes , Staphylococcus/efeitos dos fármacosRESUMO
Orthopedic injuries constitute the majority of wounds sustained by U.S. soldiers in recent conflicts. The risk of infection is considerable with fracture fixation devices. In this pilot study, we examined the use of unique bactericidal micron-thin sol-gel films on fracture fixation devices and their ability to prevent and eradicate infections. External fixation was studied with micron-thin sol-gel coated percutaneous pins releasing triclosan and inserted medially into rabbit tibiae. A total of 11 rabbits received percutaneous pins that were either uncoated or sol-gel/triclosan coated. Internal fracture fixation was also studied using sol-gel coated intramedullary (IM) nails releasing vancomycin in the intramedullary tibiae. Six sheep received IM nails that were coated with a sol-gel film that either contained vancomycin or did not contain vancomycin. All animals were challenged with Staphylococcus aureus around the implant. Animals were euthanized at 1 month postoperative. Rabbits receiving triclosan/sol-gel coated percutaneous pins did not show signs of infection. Uncoated percutaneous pins had a significantly higher infection rate. In the sheep study, there were no radiographic signs of osteomyelitis with vancomycin/sol-gel coated IM nails, in contrast to the observations in the control cohort. Hence, the nanostructured sol-gel controlled release technology offers the promise of a reliable and continuous delivery system of bactericidals from orthopedic devices to prevent and treat infection.
Assuntos
Antibacterianos/administração & dosagem , Anti-Infecciosos Locais/administração & dosagem , Pinos Ortopédicos/microbiologia , Nanoestruturas/uso terapêutico , Infecções Relacionadas à Prótese/prevenção & controle , Infecções Estafilocócicas/prevenção & controle , Animais , Sistemas de Liberação de Medicamentos , Feminino , Géis , Masculino , Projetos Piloto , Coelhos , Ovinos , Triclosan/administração & dosagem , Vancomicina/administração & dosagemRESUMO
The purpose of the present study was to fabricate fibroblast growth factor (FGF)-2-apatite composite layers on titanium (Ti) pins in one step at 25 °C using a supersaturated calcium phosphate (CaP) solution, and to evaluate the physicochemical characteristics and biological effects of the coated Ti pins compared with coated Ti pins fabricated at 37 °C. Ti pins were immersed in a supersaturated CaP solution containing 0.5, 1.0, or 2.0 µg/mL FGF-2 at 25 °C for 24 h (25F0.5, 25F1.0, and 25F2.0) or containing 4.0 µg/mL FGF-2 at 37 °C for 48 h (37F4.0). Except for the 25F0.5, the chemical compositions and the mitogenic activity levels of FGF-2 of the composite layers formed by these two methods were similar, except for the Ca/P molar ratio, which was markedly smaller at 25 °C (1.55-1.56±0.01-0.02, p=0.0008-0.0045) than at 37 °C (1.67±0.11). Thus, either the apatite was less mature or the amount of amorphous calcium phosphate was higher in the composite layer formed at 25 °C. In vivo, the pin tract infection rate by visual inspection for 37F4.0 (45%) was lower than that for 25F1.0 (80%, p=0.0213), and the rate of osteomyelitis for 37F4.0 (35%) was lower than that for 25F0.5 (75%, p=0.0341). The extraction torque for 37F4.0 (0.276±0.117 Nm) was higher than that for 25F0.5 (0.192±0.117 Nm, p=0.0142) and that for 25F1.0 (0.176±0.133 Nm, p=0.0079). The invasion rate of S. aureus for 37F4.0 (35%) was lower than that for 25F0.5 (75%, p=0.0110). On the whole, the FGF-2-apatite composite layer formed at 25 °C tended to be less effective at improving fixation strength in the bone-pin interface and resisting pin tract infections. These results suggest that the chemistry of the calcium phosphate matrix that embeds FGF-2, in addition to FGF-2 content and activity, has a significant impact on composite infection resistance and fixation strength.
Assuntos
Apatitas/química , Fosfatos de Cálcio/química , Materiais Revestidos Biocompatíveis/química , Fator 2 de Crescimento de Fibroblastos/química , Animais , Pinos Ortopédicos/efeitos adversos , Pinos Ortopédicos/microbiologia , Osso e Ossos/patologia , Materiais Revestidos Biocompatíveis/metabolismo , Escherichia coli/isolamento & purificação , Fator 2 de Crescimento de Fibroblastos/metabolismo , Inflamação/etiologia , Masculino , Camundongos , Células NIH 3T3 , Osteomielite/metabolismo , Osteomielite/microbiologia , Osteomielite/patologia , Coelhos , Staphylococcus aureus/isolamento & purificação , Titânio/químicaRESUMO
Biofilm formation represents a unique mechanism by which Staphylococcus aureus and other microorganisms avoid antimicrobial clearance and establish chronic infections. Treatment of these infections can be challenging, because the bacteria in the biofilm state are often resistant to therapies that are effective against planktonic bacteria of the same species. Effective animal models for the study of biofilm infections and novel therapeutics are needed. In addition, there is substantial interest in the use of noninvasive, in vivo data collection techniques to decrease the animal numbers required for the execution of infectious disease studies. To ad- dress these needs, we evaluated 3 murine models of implant-associated biofilm infection by using in vivo bioluminescent imaging techniques. The goal of these studies was to identify the model that was most amenable to development of sustained infections that could be imaged repeatedly in vivo by using bioluminescent technology. We found that the subcutaneous mesh and tibial intramedullary pin models both maintained consistent levels of bioluminescence for as long as 35 d after infection, with no implant loss experienced in either model. In contrast, a subcutaneous catheter model demonstrated significant incidence of incisional ab- scessation and implant loss by day 20 after infection. The correlation of bioluminescent measurements and bacterial enumeration was strongest with the subcutaneous mesh model. Among the 3 models we evaluated, the subcutaneous mesh model is the most appropriate animal model for prolonged study of biofilm infections by using bioluminescent imaging.
Assuntos
Biofilmes , Infecções Relacionadas a Cateter/microbiologia , Imagem Óptica , Infecções Relacionadas à Prótese/microbiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/crescimento & desenvolvimento , Animais , Carga Bacteriana , Pinos Ortopédicos/microbiologia , Infecções Relacionadas a Cateter/patologia , Cateteres de Demora/microbiologia , Modelos Animais de Doenças , Feminino , Luciferases Bacterianas/biossíntese , Luciferases Bacterianas/genética , Medições Luminescentes , Camundongos , Camundongos Endogâmicos ICR , Infecções Relacionadas à Prótese/patologia , Infecções Estafilocócicas/patologia , Staphylococcus aureus/genética , Staphylococcus aureus/metabolismo , Telas Cirúrgicas/microbiologia , Fatores de TempoRESUMO
BACKGROUND: Implant infection is one of the most severe complications within the field of orthopaedic surgery, associated with an enormous burden for the healthcare system. During the last decades, attempts have been made to lower the incidence of implant-related infections. In the case of cemented prostheses, the use of antibiotic-containing bone cement can be effective. However, in the case of non-cemented prostheses, osteosynthesis and spinal surgery, local antibacterial prophylaxis is not a standard procedure. For the development of implant coatings with antibacterial properties, there is a need for a reliable animal model to evaluate the preventive capacity of such coatings during a specific period of time. Existing animal models generally present a limited follow-up, with a limited number of outcome parameters and relatively large animal numbers in multiple groups. METHODS: To represent an early post-operative implant infection, we established an acute tibial intramedullary nail infection model in rabbits by contamination of the tibial nail with 3.8 × 105 colony forming units of Staphylococcus aureus. Clinical, haematological and radiological parameters for infection were weekly assessed during a 6-week follow-up with post-mortem bacteriological and histological analyses. RESULTS: S. aureus implant infection was confirmed by the above parameters. A saline control group did not develop osteomyelitis. By combining the clinical, haematological, radiological, bacteriological and histological data collected during the experimental follow-up, we were able to differentiate between the control and the infected condition and assess the severity of the infection at sequential timepoints in a parameter-dependent fashion. CONCLUSION: We herein present an acute early post-operative rabbit implant infection model which, in contrast to previously published models, combines improved in-time insight into the development of an implant osteomyelitis with a relatively low amount of animals.
Assuntos
Pinos Ortopédicos/microbiologia , Modelos Animais de Doenças , Osteomielite/microbiologia , Infecções Relacionadas à Prótese/microbiologia , Infecções Estafilocócicas/diagnóstico , Doença Aguda , Animais , Contagem de Colônia Microbiana , Contaminação de Equipamentos , Feminino , Osteomielite/sangue , Osteomielite/diagnóstico , Exame Físico/métodos , Infecções Relacionadas à Prótese/sangue , Infecções Relacionadas à Prótese/diagnóstico , Coelhos , Infecções Estafilocócicas/sangue , Staphylococcus aureus/isolamento & purificação , Tíbia/microbiologia , Tíbia/cirurgia , Microtomografia por Raio-X/métodosRESUMO
PURPOSE: In contrast to a large amount of epidemiological data regarding the incidence of implant infections after fracture management, surprisingly few have been published concerning the success of their treatment. METHODS: This was a single-centre cohort study at Geneva University Hospitals from 2000 to 2012 investigating the remission rates of orthopaedic implant infections after fracture repair and associated variables. RESULTS: A total of 139 episodes were included: There were 51 women (37%) and 28 immunosuppressed (20%) patients with a median age and American Society of Anaesthesiologists (ASA) score of 51 years and 2 points, respectively. The infected implants were plates (n = 75, 54 %), nails (24, 17%), wires (20), screws (10), cerclage cables or wires (3), hip screws (4) or material for spondylodesis (3). A pathogen was identified in 135 (97%) cases, including Staphylococcus aureus (73, 52%), coagulase-negative staphylococci (20), streptococci (7) and 19 Gram-negative rods. All patients underwent antibiotic treatment, and 128 (92%) remained in remission at a median follow-up time of 2.6 years (range one to 13 years). In multivariate logistic regression analysis, the plate infections were significantly associated with lower remission rates [65/75, 87%, odds ratio (OR) 0.1, 95% confidence interval (CI) 0.01-0.90]. No associations were found for gender, age, immune status, ASA score, additional surgical interventions (OR 0.4, 95% CI 0.1-4.1) or duration of antibiotic treatment (OR 1.0, 95% CI 0.98-1.01). CONCLUSIONS: Among all infected and removed orthopaedic implants, plates were associated with slightly lower remission rates, while the overall treatment success exceeded 90%. The duration of antibiotic therapy did not alter the outcome.
Assuntos
Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/epidemiologia , Fixação Interna de Fraturas/instrumentação , Fraturas Ósseas/cirurgia , Fixadores Internos/microbiologia , Infecção da Ferida Cirúrgica/epidemiologia , Infecção da Ferida Cirúrgica/terapia , Adulto , Idoso , Antibacterianos/uso terapêutico , Pinos Ortopédicos/efeitos adversos , Pinos Ortopédicos/microbiologia , Placas Ósseas/efeitos adversos , Placas Ósseas/microbiologia , Parafusos Ósseos/efeitos adversos , Parafusos Ósseos/microbiologia , Fios Ortopédicos/efeitos adversos , Fios Ortopédicos/microbiologia , Estudos de Coortes , Feminino , Seguimentos , Fixação Interna de Fraturas/métodos , Humanos , Incidência , Fixadores Internos/efeitos adversos , Masculino , Pessoa de Meia-Idade , Indução de Remissão , Reoperação , Estudos Retrospectivos , Infecção da Ferida Cirúrgica/microbiologia , Resultado do TratamentoRESUMO
Biomaterials-associated infection incidence represents an increasing clinical challenge as more people gain access to medical device technologies worldwide and microbial resistance to current approaches mounts. Few reported antimicrobial approaches to implanted biomaterials ever get commercialized for physician use and patient benefit. This is not for lack of ideas since many thousands of claims to new approaches to antimicrobial efficacy are reported. Lack of translation of reported ideas into medical products approved for use, results from conflicting goals and purposes between the various participants involved in conception, validation, development, commercialization, safety and regulatory oversight, insurance reimbursement, and legal aspects of medical device innovation. The scientific causes, problems and impressive costs of the limiting clinical options for combating biomaterials-associated infection are well recognized. Demands for improved antimicrobial technologies constantly appear. Yet, the actual human, ethical and social costs and consequences of their occurrence are less articulated. Here, we describe several clinical cases of biomaterials-associated infections to illustrate the often-missing human elements of these infections. We identify the current societal forces at play in translating antimicrobial research concepts into clinical implant use and their often-orthogonal constituencies, missions and policies. We assert that in the current complex environment between researchers, funding agencies, physicians, patients, providers, producers, payers, regulatory agencies and litigators, opportunities for translatable successes are minimized under the various risks assumed in the translation process. This argues for an alternative approach to more effectively introduce new biomaterials and device technologies that can address the clinical issues by providing patients and medical practitioners new options for desperate clinical conditions ineffectively addressed by biomedical innovation.
Assuntos
Antibacterianos/uso terapêutico , Materiais Biocompatíveis/efeitos adversos , Próteses e Implantes/efeitos adversos , Infecções Relacionadas à Prótese/tratamento farmacológico , Infecções Relacionadas à Prótese/etiologia , Adolescente , Idoso , Ruptura Aórtica/complicações , Ruptura Aórtica/cirurgia , Artroplastia de Quadril/efeitos adversos , Prótese Vascular/efeitos adversos , Prótese Vascular/microbiologia , Pinos Ortopédicos/microbiologia , Endocardite/tratamento farmacológico , Endocardite/etiologia , Endocardite/microbiologia , Feminino , Fraturas Ósseas/complicações , Fraturas Ósseas/microbiologia , Próteses Valvulares Cardíacas/efeitos adversos , Próteses Valvulares Cardíacas/microbiologia , Prótese de Quadril/efeitos adversos , Prótese de Quadril/microbiologia , Humanos , Laringe Artificial/efeitos adversos , Laringe Artificial/microbiologia , Traumatismos da Perna/complicações , Traumatismos da Perna/microbiologia , Masculino , Pessoa de Meia-Idade , Próteses e Implantes/microbiologia , Infecções Relacionadas à Prótese/microbiologiaRESUMO
PURPOSE. To evaluate the efficacy of antibiotic-coated pins for prevention of pin tract infection in a rabbit model. METHODS. 10 rabbits were divided into 2 groups. A unilateral external fixator was applied to the tibia with 4 self-taping 1.8-mm pins. In the test group, pins were coated with hydroxyapatite and antibiotic. In the control group, pins were not coated. All pins were then placed in Staphylococcus aureus- containing media. At postoperative day 5, all 40 pin sites were subcutaneously inoculated with S aureus. The sites were clinically examined for signs of pin tract infection. Nine days later, a piece of soft tissue around the pin site was harvested for microbiologic examination. RESULTS. In the test group, all except one pin sites appeared clean and without clinical infection, and the culture media remained clear. In the control group, all pin sites showed evidence of clinical infection and yielded positive cultures, and the culture media became dark indicating growth of S aureus. CONCLUSION. Antibiotic-coated pins were effective in preventing pin tract infection.