Viable adhered Staphylococcus aureus highly reduced on novel antimicrobial sutures using chlorhexidine and octenidine to avoid surgical site infection (SSI)

Background Surgical sutures can promote migration of bacteria and thus start infections. Antiseptic coating of sutures may inhibit proliferation of adhered bacteria and avoid such complications. Objectives This study investigated the inhibition of viable adhering bacteria on novel antimicrobially coated surgical sutures using chlorhexidine or octenidine, a critical factor for proliferation at the onset of local infections. The medical need, a rapid eradication of bacteria in wounds, can be fulfilled by a high antimicrobial efficacy during the first days after wound closure. Methods As a pretesting on antibacterial efficacy against relevant bacterial pathogens a zone of inhibition assay was conducted with middle ranged concentrated suture coatings (22 mu g/cm). For further investigation of adhering bacteria in detail the most clinically relevant Staphylococcus aureus (ATCC (R) 49230 (TM)) was used. Absorbable braided sutures were coated with chlorhexidine-laurate, chlorhexidine-palmitate, octenidine-laurate, and octenidine-palmitate. Each coating type resulted in 11, 22, or 33 mu g/cm drug content on sutures. Scanning electron microscopy (SEM) was performed once to inspect the coating quality and twice to investigate if bacteria have colonized on sutures. Adhesion experiments were assessed by exposing coated sutures to S. aureus suspensions for 3 h at 37 degrees C. Subsequently, sutures were sonicated and the number of viable bacteria released from the suture surface was determined. Furthermore, the number of viable planktonic bacteria was measured in suspensions containing antimicrobial sutures. Commercially available sutures without drugs (Vicryl (R), PGA Resorba (R), and Gunze PGA), as well as triclosan-containing Vicryl (R) Plus were used as control groups. Results Zone of inhibition assay documented a multispecies efficacy of novel coated sutures against tested bacterial strains, comparable to most relevant S. aureus over 48 hours. SEM pictures demonstrated uniform layers on coated sutures with higher roughness for palmitate coatings and sustaining integrity of coated sutures. Adherent S. aureus were found via SEM on all types of investigated sutures. The novel antimicrobial sutures showed significantly less viable adhered S. aureus bacteria (up to 6.1 log) compared to Vicryl (R) Plus (0.5 log). Within 11 mu g/cm drug-containing sutures, octenidine-palmitate (OL11) showed the highest number of viable adhered S. aureus (0.5 log), similar to Vicryl (R) Plus. Chlorhexidine-laurate (CL11) showed the lowest number of S. aureus on sutures (1.7 log), a 1.2 log greater reduction. In addition, planktonic S. aureus in suspensions were highly inhibited by CL11 (0.9 log) represents a 0.6 log greater reduction compared to Vicryl (R) Plus (0.3 log). Conclusions Novel antimicrobial sutures can potentially limit surgical site infections caused by multiple pathogenic bacterial species. Therefore, a potential inhibition of multispecies biofilm formation is assumed. In detail tested with S. aureus, the chlorhexidine-laurate coating (CL11) best meets the medical requirements for a fast bacterial eradication. This suture coating shows the lowest survival rate of adhering as well as planktonic bacteria, a high drug release during the first-clinically most relevant-48 hours, as well as biocompatibility. Thus, CL11 coatings should be recommended for prophylactic antimicrobial sutures as an optimal surgical supplement to reduce wound infections. However, animal and clinical investigations are important to prove safety and efficacy for future applications

Radiological tarsal bone morphology in adolescent age of congenital clubfeet treated with the Ponseti method

Background!#!Major abnormalities of tarsal bone shape after surgical clubfoot treatment are well known from the literature. The Ponseti method has gained widespread acceptance in primary treatment of congenital clubfeet. Despite the longtime experience, data regarding the development of tarsal bones after this treatment are still rare. The aim of the study was therefore to evaluate radiographic parameters describing tarsal bone shape of clubfeet after Ponseti treatment and compare them to age-matched healthy feet.!##!Methods!#!Twenty two consecutive severe clubfeet in 14 patients were investigated by repeated diagnostic ultrasound during the corrective process. Extent and temporal course of correction were documented with standardized X-rays after a mean follow-up of 12 years (between the ages of 10-14 years) and compared to a group of age-matched normal feet.!##!Results!#!Reliability testing for all X-ray parameters showed good to excellent results. In comparison to the control group, all parameters except the radius of the trochlea (RT) were significantly altered in clubfeet with highest differences shown for the anterior talar motion segment (ATM), talonavicular coverage (TNC) and the talometatarsal index (TMT-Index). Differentiation between minor and major deformities showed significant differences only for the front tarsal index (FTI).!##!Conclusions!#!Tarsal bone shape of clubfeet treated by the Ponseti method differs significantly from normal feet. One of the most pronounced and clinically relevant difference of the clubfoot talus compared to the normal talus is the markedly reduced anterior talar motion segment

Is it possible to define reference values for radiographic parameters evaluating juvenile flatfoot deformity? A case-control study

Background!#!Numerous radiographic parameters are described to evaluate juvenile flexible flatfeet. Reference values for these measurements are based on few studies. The purpose of this study was to determine boundary values among the most widely used radiographic measurements to evaluate juvenile flatfeet.!##!Methods!#!Twenty-two patients with normal hind-, midfoot configuration (group A: control group; 22 ft, mean age: 12,1 years) and 19 patients with flatfoot deformity (group B: study group; 22 ft, mean age: 12,4 years) were retrospectively analyzed. Nine radiographic parameters were measured (Talocalcaneal-angles, Calcaneal-pitch-angle, Costa-Bartani-angle, Talo-metatarsal-I-angles, Talo-first-metatarsal-base-angle, Talo-navicular-coverage, Calcaneus-fifth-metatarsal-angle). ROC curve analysis was used to calculate optimal differentiating thresholds of each parameter.!##!Results!#!Four out of nine parameters (TC-dp, TC-lat, Calc-MTV, Calc-P) were not statistically different between the groups and their ability to distinct between normal foot and flatfoot was low (AUC values = 0,660 - 0,819). Calculation of reference values for these parameters was not performed due to threshold ranges between the groups of > 10°. Reference values could be defined only for three parameters: TMTInd >(-)31°, TMTIB >(-)7,5°, TMT-lat > (-)13,5°. The TMTInd was shown to be a very reliable and valid combination of two measurements (TMTIB and TMT-lat) in the differentiation of normal feet and flatfeet (AUC = 0,998).!##!Conclusion!#!The calculation of reference values for established radiographic parameters used to evaluate juvenile flatfeet is difficult for most parameters. The TMTInd as a combination of TMTIB and TMT-lat has been shown to be reliable and valuable to distinct normal feet from flatfeet

A biocompatible sol–gel derived titania coating for medical implants with antibacterial modification by copper integration

Abstract Implant-associated infections are dangerous complications and may cause dramatic illness with hematogeneous spread of bacteria and secondary infections. Since treatment of these infections remains most challenging and commonly requires implant removal, prevention is of utmost importance. In the present work a titania-sol was equipped with a copper salt resulting after calcination in a titania coating (TiO2) with antibacterial properties combined with good cytocompatibility. In vitro tests with bacteria as well as tissue cells were carried out under corresponding conditions. Mouse fibroblasts and different staphylococcal strains were used for growth inhibition assays with serial dilutions of CuCl2. Cultivation on the surface of bare Ti6Al4V, TiO2-coated and copper-filled TiO2-coated Ti6Al4V samples was performed with both bacteria and tissue cells. Bacterial and cellular proliferation and mitochondrial activity were hereby determined. Coating of Ti6Al4V with pure TiO2 significantly improved cytocompatibility compared to the uncoated alloy. In the growth inhibition assays, fibroblasts tolerated higher concentrations of copper ions than did bacteria. Nevertheless, copper integration reduced fibroblast proliferation and mitochondrial activity on the surface coating. On the other hand, integration of copper into the TiO2-coating significantly reduced adhesion of viable bacteria resulting in a promising combination of cytocompatibility and antibacterial properties. Additionally, significant bacterial growth inhibition by antibacterial amounts of copper was also demonstrated in the supernatant. In conclusion, the copper-loaded TiO2-coatings for medical implants may be a promising approach to reduce the rate of implant-associated infections

Distribution patterns of foot and ankle tumors: a university tumor institute experience

Abstract Background Bone and soft tissue masses of the foot and ankle are not particularly rare but true neoplasia has to be strictly differentiated from pseudotumorous lesions. Diagnosis is often delayed as diagnostic errors are more common than in other regions. Awareness for this localization of musculoskeletal tumors is not very high and neoplasia is often not considered. The purpose of this study is to provide detailed information on the incidence and distribution patterns of foot and ankle tumors of a university tumor institute and propose a simple definition to facilitate comparison of future investigations. Methods As part of a retrospective, single-centre study, the data of patients that were treated for foot and ankle tumors between June 1997 and December 2015 in a musculoskeletal tumor centre were analyzed regarding epidemiologic information, entity and localization. Included were all cases with a true tumor of the foot and ankle. Exclusion criteria were incomplete information on the patient or entity (e.g. histopathological diagnosis) and all pseudotumoral lesions. Results Out of 7487 musculoskeletal tumors, 413 cases (5,52%) of tumors of the foot and ankle in 409 patients were included (215 male and 198 female patients). The average age of the affected patients was 36 ± 18y (min.3y, max.92y). Two hundred sixty-six tumors involved the bone (64%), among them 231 (87%) benign and 35 (13%) malignant. There were 147 soft tissue tumors (36%), 104 (71%) were benign, 43 (29%) malignant. The most common benign osseous tumor lesions included simple bone cysts, enchondroma and osteochondroma. By far the most common malignant bone tumor was chondrosarcoma. Common benign soft tissue tumors included pigmented villo-nodular synovitis, superifcial fibromatosis and schwannoma whereas the most common malignant members were synovial sarcoma and myxofibrosarcoma. Regarding anatomical localization, the hindfoot was affected most often. Conclusions Knowledge of incidence and distribution patterns of foot and ankle tumors will help to correctly assess unclear masses and initiate the right steps in further diagnostics and treatment. Unawareness can lead to delayed diagnosis and inadequate treatment with serious consequences for the affected patient