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Antibacterial coating of implants in orthopaedics and trauma: a classification proposal in an evolving panorama.

Romanò CL, Scarponi S, Gallazzi E, Romanò D, Drago L - J Orthop Surg Res (2015)

Bottom Line: Passive surface finishing/modification (PSM): passive coatings that do not release bactericidal agents to the surrounding tissues, but are aimed at preventing or reducing bacterial adhesion through surface chemistry and/or structure modifications; 2.Active surface finishing/modification (ASM): active coatings that feature pharmacologically active pre-incorporated bactericidal agents; and 3.Classifying different technologies may be useful in order to better compare different solutions, to improve the design of validation tests and, hopefully, to improve and speed up the regulatory process in this rapidly evolving field.

View Article: PubMed Central - PubMed

Affiliation: Department of Reconstructive Surgery of Osteo-articular Infections C.R.I.O. Unit, IRCCS Galeazzi Orthopaedic Institute, Via R. Galeazzi 4, 20161, Milan, Italy. carlo.romano@grupposandonato.it.

ABSTRACT
Implanted biomaterials play a key role in current success of orthopedic and trauma surgery. However, implant-related infections remain among the leading reasons for failure with high economical and social associated costs. According to the current knowledge, probably the most critical pathogenic event in the development of implant-related infection is biofilm formation, which starts immediately after bacterial adhesion on an implant and effectively protects the microorganisms from the immune system and systemic antibiotics. A rationale, modern prevention of biomaterial-associated infections should then specifically focus on inhibition of both bacterial adhesion and biofilm formation. Nonetheless, currently available prophylactic measures, although partially effective in reducing surgical site infections, are not based on the pathogenesis of biofilm-related infections and unacceptable high rates of septic complications, especially in high-risk patients and procedures, are still reported.In the last decade, several studies have investigated the ability of implant surface modifications to minimize bacterial adhesion, inhibit biofilm formation, and provide effective bacterial killing to protect implanted biomaterials, even if there still is a great discrepancy between proposed and clinically implemented strategies and a lack of a common language to evaluate them.To move a step forward towards a more systematic approach in this promising but complicated field, here we provide a detailed overview and an original classification of the various technologies under study or already in the market. We may distinguish the following: 1. Passive surface finishing/modification (PSM): passive coatings that do not release bactericidal agents to the surrounding tissues, but are aimed at preventing or reducing bacterial adhesion through surface chemistry and/or structure modifications; 2. Active surface finishing/modification (ASM): active coatings that feature pharmacologically active pre-incorporated bactericidal agents; and 3. Local carriers or coatings (LCC): local antibacterial carriers or coatings, biodegradable or not, applied at the time of the surgical procedure, immediately prior or at the same time of the implant and around it. Classifying different technologies may be useful in order to better compare different solutions, to improve the design of validation tests and, hopefully, to improve and speed up the regulatory process in this rapidly evolving field.

No MeSH data available.


Related in: MedlinePlus

a Radiographic antero-posterior view of sequelae of a septic hip arthritis (S. aureus) in a 52-year-old female patient. b Teicoplanin 5 % loaded DAC® hydrogel is applied on the sanded titanium surface of a standard cementless hip prosthesis, both on the stem and c in the acetabulum component that may be press-fit inserted according to a normal procedure (arrow indicates some hydrogel squeezed out during cup insertion). d Control after 12 months shows optimal bone osteointegration (arrows). The patient is pain- and infection-free
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Fig2: a Radiographic antero-posterior view of sequelae of a septic hip arthritis (S. aureus) in a 52-year-old female patient. b Teicoplanin 5 % loaded DAC® hydrogel is applied on the sanded titanium surface of a standard cementless hip prosthesis, both on the stem and c in the acetabulum component that may be press-fit inserted according to a normal procedure (arrow indicates some hydrogel squeezed out during cup insertion). d Control after 12 months shows optimal bone osteointegration (arrows). The patient is pain- and infection-free

Mentions: Biocompatible hydrogels do represent a possible alternative solution, as they have demonstrated to be able to deliver local pharmacological agents and may be designed to meet the desired elution pattern [109]. Recently, a fast-resorbable hydrogel coating, that can be loaded intra-operatively with various antibacterials, has been introduced in the European market [110]. Based on the facts that bacterial colonization occurs within the very first hours after implant and that short-term systemic prophylaxis is equally effective as the long-term one to prevent PJIs [111], this novel coating technology introduced the “short-term local protection” of the implant. A short-term local delivery system may in fact meet the requirements needed to win the “run to the surface”, while limiting possible long-term unwanted side effects [112]. This novel fast-resorbable hydrogel coating, “Defensive Antibacterial Coating”, DAC® (Novagenit Srl, Mezzolombardo, Italy), composed of covalently linked hyaluronan and poly-D,L-lactide, (Fig. 1), is designed to undergo complete hydrolytic degradation in vivo within 48 to 72 h, being able to completely release a variety of different antibacterials, including glycopeptides, amynoglycosides, and fluoquinolones (Table 3), at concentrations ranging from 2 % to 10 %. The hydrogel showed a synergistic antibacterial activity with various antibiotics and antibiofilm agents in vitro [113], while in vivo it has been proven effective a rabbit model of highly contaminated implant both with [114] and without systemic prophylaxis [115]. An ongoing European multicenter clinical trial (Fig. 2) is currently investigating the safety and the efficacy of the device [116].Fig. 1


Antibacterial coating of implants in orthopaedics and trauma: a classification proposal in an evolving panorama.

Romanò CL, Scarponi S, Gallazzi E, Romanò D, Drago L - J Orthop Surg Res (2015)

a Radiographic antero-posterior view of sequelae of a septic hip arthritis (S. aureus) in a 52-year-old female patient. b Teicoplanin 5 % loaded DAC® hydrogel is applied on the sanded titanium surface of a standard cementless hip prosthesis, both on the stem and c in the acetabulum component that may be press-fit inserted according to a normal procedure (arrow indicates some hydrogel squeezed out during cup insertion). d Control after 12 months shows optimal bone osteointegration (arrows). The patient is pain- and infection-free
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4591707&req=5

Fig2: a Radiographic antero-posterior view of sequelae of a septic hip arthritis (S. aureus) in a 52-year-old female patient. b Teicoplanin 5 % loaded DAC® hydrogel is applied on the sanded titanium surface of a standard cementless hip prosthesis, both on the stem and c in the acetabulum component that may be press-fit inserted according to a normal procedure (arrow indicates some hydrogel squeezed out during cup insertion). d Control after 12 months shows optimal bone osteointegration (arrows). The patient is pain- and infection-free
Mentions: Biocompatible hydrogels do represent a possible alternative solution, as they have demonstrated to be able to deliver local pharmacological agents and may be designed to meet the desired elution pattern [109]. Recently, a fast-resorbable hydrogel coating, that can be loaded intra-operatively with various antibacterials, has been introduced in the European market [110]. Based on the facts that bacterial colonization occurs within the very first hours after implant and that short-term systemic prophylaxis is equally effective as the long-term one to prevent PJIs [111], this novel coating technology introduced the “short-term local protection” of the implant. A short-term local delivery system may in fact meet the requirements needed to win the “run to the surface”, while limiting possible long-term unwanted side effects [112]. This novel fast-resorbable hydrogel coating, “Defensive Antibacterial Coating”, DAC® (Novagenit Srl, Mezzolombardo, Italy), composed of covalently linked hyaluronan and poly-D,L-lactide, (Fig. 1), is designed to undergo complete hydrolytic degradation in vivo within 48 to 72 h, being able to completely release a variety of different antibacterials, including glycopeptides, amynoglycosides, and fluoquinolones (Table 3), at concentrations ranging from 2 % to 10 %. The hydrogel showed a synergistic antibacterial activity with various antibiotics and antibiofilm agents in vitro [113], while in vivo it has been proven effective a rabbit model of highly contaminated implant both with [114] and without systemic prophylaxis [115]. An ongoing European multicenter clinical trial (Fig. 2) is currently investigating the safety and the efficacy of the device [116].Fig. 1

Bottom Line: Passive surface finishing/modification (PSM): passive coatings that do not release bactericidal agents to the surrounding tissues, but are aimed at preventing or reducing bacterial adhesion through surface chemistry and/or structure modifications; 2.Active surface finishing/modification (ASM): active coatings that feature pharmacologically active pre-incorporated bactericidal agents; and 3.Classifying different technologies may be useful in order to better compare different solutions, to improve the design of validation tests and, hopefully, to improve and speed up the regulatory process in this rapidly evolving field.

View Article: PubMed Central - PubMed

Affiliation: Department of Reconstructive Surgery of Osteo-articular Infections C.R.I.O. Unit, IRCCS Galeazzi Orthopaedic Institute, Via R. Galeazzi 4, 20161, Milan, Italy. carlo.romano@grupposandonato.it.

ABSTRACT
Implanted biomaterials play a key role in current success of orthopedic and trauma surgery. However, implant-related infections remain among the leading reasons for failure with high economical and social associated costs. According to the current knowledge, probably the most critical pathogenic event in the development of implant-related infection is biofilm formation, which starts immediately after bacterial adhesion on an implant and effectively protects the microorganisms from the immune system and systemic antibiotics. A rationale, modern prevention of biomaterial-associated infections should then specifically focus on inhibition of both bacterial adhesion and biofilm formation. Nonetheless, currently available prophylactic measures, although partially effective in reducing surgical site infections, are not based on the pathogenesis of biofilm-related infections and unacceptable high rates of septic complications, especially in high-risk patients and procedures, are still reported.In the last decade, several studies have investigated the ability of implant surface modifications to minimize bacterial adhesion, inhibit biofilm formation, and provide effective bacterial killing to protect implanted biomaterials, even if there still is a great discrepancy between proposed and clinically implemented strategies and a lack of a common language to evaluate them.To move a step forward towards a more systematic approach in this promising but complicated field, here we provide a detailed overview and an original classification of the various technologies under study or already in the market. We may distinguish the following: 1. Passive surface finishing/modification (PSM): passive coatings that do not release bactericidal agents to the surrounding tissues, but are aimed at preventing or reducing bacterial adhesion through surface chemistry and/or structure modifications; 2. Active surface finishing/modification (ASM): active coatings that feature pharmacologically active pre-incorporated bactericidal agents; and 3. Local carriers or coatings (LCC): local antibacterial carriers or coatings, biodegradable or not, applied at the time of the surgical procedure, immediately prior or at the same time of the implant and around it. Classifying different technologies may be useful in order to better compare different solutions, to improve the design of validation tests and, hopefully, to improve and speed up the regulatory process in this rapidly evolving field.

No MeSH data available.


Related in: MedlinePlus