The Role of Negative-Pressure Wound Therapy in Patients with Fracture-Related Infection:A Systematic Review and Critical Appraisal

INTRODUCTION: Fracture-related infection (FRI) is a severe musculoskeletal complication in orthopedic trauma surgery, causing challenges in bony and soft tissue management. Currently, negative-pressure wound therapy (NPWT) is often used as temporary coverage for traumatic and surgical wounds, also in cases of FRI. However, controversy exists about the impact of NPWT on the outcome in FRI, specifically on infection recurrence. Therefore, this systematic review qualitatively assesses the literature on the role of NPWT in the management of FRI. METHODS: A literature search of the PubMed, Embase, and Web of Science database was performed. Studies that reported on infection recurrence related to FRI management combined with NPWT were eligible for inclusion. Quality assessment was done using the PRISMA statement and the Newcastle-Ottawa Quality Assessment Scale. RESULTS: After screening and quality assessment of 775 unique identified records, eight articles could be included for qualitative synthesis. All eight studies reported on infection recurrence, which ranged from 2.8% to 34.9%. Six studies described wound healing time, varying from two to seven weeks. Four studies took repeated microbial swabs during subsequent vacuum dressing changes. One study reported newly detected pathogens in 23% of the included patients, and three studies did not find new pathogens. CONCLUSION: This review provides an assessment of current literature on the role of NPWT in the management of soft tissue defects in patients with FRI. Due to the lack of uniformity in included studies, conclusions should be drawn with caution. Currently, there is no clear scientific evidence to support the use of NPWT as definitive treatment in FRI. At this stage, we can only recommend early soft tissue coverage (within days) with a local or free flap. NPWT may be safe for a few days as temporarily soft tissue coverage until definitive soft tissue management could be performed. However, comparative studies between NPWT and early wound closure in FRI patients are needed

Human monoclonal antibodies against Staphylococcus aureus surface antigens recognize in vitro and in vivo biofilm

Implant-associated Staphylococcus aureus infections are difficult to treat because of biofilm formation. Bacteria in a biofilm are often insensitive to antibiotics and host immunity. Monoclonal antibodies (mAbs) could provide an alternative approach to improve the diagnosis and potential treatment of biofilm-related infections. Here, we show that mAbs targeting common surface components of S. aureus can recognize clinically relevant biofilm types. The mAbs were also shown to bind a collection of clinical isolates derived from different biofilm-associated infections (endocarditis, prosthetic joint, catheter). We identify two groups of antibodies: one group that uniquely binds S. aureus in biofilm state and one that recognizes S. aureus in both biofilm and planktonic state. Furthermore, we show that a mAb recognizing wall teichoic acid (clone 4497) specifically localizes to a subcutaneously implanted pre-colonized catheter in mice. In conclusion, we demonstrate the capacity of several human mAbs to detect S. aureus biofilms in vitro and in vivo

Prevention : T

Joint replacement is a successful surgical procedure that provides pain relief, restores joint function and improves the quality of life of patients. A minority of patients will experience complications like aseptic failure or prosthetic joint infection (PJI; Tande and Patel 2014)

An uncemented iso-elastic monoblock acetabular component : Preliminary results

Little is known about the clinical application of highly cross-linked polyethylene (HXLPE) blended with vitamin E. This study evaluates an uncemented iso-elastic monoblock cup with vitamin E blended HXLPE. 112 patients were followed up for 2. years. 95.5% completed the follow-up. The mean VAS score for patient satisfaction was 8.8 and the mean Harris Hip Score was 94.2. In 7 cases initial gaps behind the cup were observed, which disappeared completely during follow-up in 6 cases. The mean femoral head penetration rate was 0.055. mm/year. No adverse reactions or abnormal mechanical behavior was observed with the short term use of vitamin E blended HXLPE. This study shows the promising performance of this cup and confirms the potential of vitamin E blended HXLPE

Deformable titanium for acetabular revision surgery: a proof of concept

Abstract Custom-made triflange acetabular implants are increasingly used in complex revision surgery where supporting bone stock is diminished. In most cases these triflange cups induce stress-shielding. A new concept for the triflange is introduced that uses deformable porous titanium to redirect forces from the acetabular rim to the bone stock behind the implant and thereby reduces further stress-shielding. This concept is tested for deformability and primary stability. Three different designs of highly porous titanium cylinders were tested under compression to determine their mechanical properties. The most promising design was used to design five acetabular implants either by incorporating a deformable layer at the back of the implant or by adding a separate generic deformable mesh behind the implant. All implants were inserted into sawbones with acetabular defects followed by a cyclic compression test of 1800N for 1000 cycles. The design with a cell size of 4 mm and 0.2 mm strut thickness performed the best and was applied for the design of the acetabular implants. An immediate primary fixation was realized in all three implants with an incorporated deformable layer. One of the two implants with a separate deformable mesh needed fixation with screws. Cyclic tests revealed an average additional implant subsidence of 0.25 mm that occurred in the first 1000 cycles with minimal further subsidence thereafter. It is possible to realize primary implant fixation and stability in simulated large acetabular revision surgery using a deformable titanium layer behind the cup. Additional research is needed for further implementation of such implants in the clinic

The efficacy of intrawound vancomycin powder and povidone-iodine irrigation to prevent surgical site infections in complex instrumented spine surgery

BACKGROUND CONTEXT: Surgical site infections (SSIs) are notorious complications in spinal surgery and cause substantial patient morbidity. Intraoperative decontamination of the wound with povidone-iodine irrigation or vancomycin powder has gained attention lately, but the efficacy of either intervention is unclear. PURPOSE: To determine the efficacy of intrawound povidone-iodine or vancomycin in reducing the incidence of deep- and superficial SSIs in instrumented spinal surgery. STUDY DESIGN/SETTING: Retrospective cohort study. PATIENT SAMPLE: A retrospective chart review was performed including all consecutive adult patients undergoing open, posterior, instrumented spinal surgery at any level between January 2012 and August 2017. OUTCOME MEASURES: The presence of SSI was evaluated according to the criteria published by the Centers for Disease Control and Prevention. The SSIs were divided into deep SSIs (below the muscular fascia) and superficial SSIs (above the muscular fascia). METHODS: A retrospective cohort without intrawound treatment was compared with two separate, consecutive intervention groups. One intrawound group received 1.3g/L povidone-iodine irrigation and the other received 1-2 grams of intrawound vancomycin powder at the end of surgery. Incidence of SSIs, as well as demographic, surgical and patient-related variables were registered and compared between groups. In patients with SSI, additional microbiological data were collected. RESULTS: In total, 853 patients were included. In the control group (N=257), 25 (9.7%) patients developed a deep and 13 (5.1%) developed a superficial SSI. In the povidone-iodine group (N=217), 21 (9.7%) patients developed a deep and two (0.9%) developed a superficial SSI. Compared with the control group, there was no significant difference in the incidence of deep SSIs (risk ratio [RR]: 1.00, 95% CI 0.57–1.73), although the number of superficial SSIs was reduced significantly (RR 0.18, 95% CI 0.04–0.80). In the vancomycin group (N=379), 19 (5.0%) patients developed a deep and six (1.6%) developed a superficial SSI. Both deep (RR: 0.52, 95% CI 0.29–0.92) and superficial SSIs (RR: 0.31, 95% CI 0.12–0.81) were significantly reduced in the vancomycin group compared with the control group, even when correcting for several risk factors associated with SSIs in a multivariable logistic regression analysis. There were no significant differences in complications between the 3 groups. No gram-negative selection or vancomycin-resistance was seen in the vancomycin group. CONCLUSIONS: Intrawound application of vancomycin was associated with a significant reduction in both deep and superficial SSIs in instrumented spinal surgery. A 1.3g/L intrawound povidone-iodine solution did not show a reduction in deep SSIs, although a reduction of superficial SSIs was observed

Hyaluronic Acid-Based Hydrogel Coating Does Not Affect Bone Apposition at the Implant Surface in a Rabbit Model

BACKGROUND: Uncemented orthopaedic implants rely on the bone-implant interface to provide stability, therefore it is essential that a coating does not interfere with the bone-forming processes occurring at the implant interface. In addition, local application of high concentrations of antibiotics for prophylaxis or treatment of infection may be toxic for osteoblasts and could impair bone growth. QUESTIONS/PURPOSES: In this animal study, we investigated the effect of a commercially available hydrogel, either unloaded or loaded with 2% vancomycin. We asked, does unloaded hydrogel or hydrogel with vancomycin (1) interfere with bone apposition and timing of bone deposition near the implant surface; and (2) induce a local or systemic inflammatory reaction as determined by inflammation around the implant and hematologic parameters. METHODS: In 18 New Zealand White rabbits, an uncoated titanium rod (n = 6), a rod coated with unloaded hydrogel (n = 6), or a rod coated with 2% vancomycin-loaded hydrogel (n = 6) was implanted in the intramedullary canal of the left tibia. After 28 days, the bone volume fraction near the implant was measured with microCT analysis, inflammation was semiquantitatively scored on histologic sections, and timing of bone apposition was followed by semiquantitative scoring of fluorochrome incorporation on histologic sections. Two observers, blinded to the treatment, scored the sections and reconciled their scores if there was a disagreement. The hematologic inflammatory reaction was analyzed by measuring total and differential leukocyte counts and erythrocyte sedimentation rates in blood. With group sizes of six animals per group, we had 79% power to detect a difference of 25% in histologic scoring for infection and inflammation. RESULTS: No differences were found in the amount of bone apposition near the implant in the No Gel group (48.65% ± 14.95%) compared with the Gel group (59.97% ± 5.02%; mean difference [MD], 11.32%; 95% CI, -3.89% to 26.53%; p = 0.16) or for the Van2 group (56.12% ± 10.06%; MD, 7.46; 95% CI, -7.75 to 22.67; p = 0.40), with the numbers available. In addition, the scores for timing of bone apposition did not differ between the No Gel group (0.50 ± 0.55) compared with the Gel group (0.33 ± 0.52; MD, -0.17; 95% CI, -0.86 to 0.53; p = 0.78) or the Van2 group (0.83 ± 0.41; MD, 0.33; 95% CI, -0.36 to 1.03; p = 0.42). Furthermore, we detected no differences in the histopathology scores for inflammation in the No Gel group (2.33 ± 1.67) compared with the Gel group (3.17 ± 1.59; MD, 0.83; 95% CI, -0.59 to 2.26; p = 0.31) or to the Van2 group (2.5 ± 1.24; MD, 0.17; 95% CI, -1.26 to 1.59; p = 0.95). Moreover, no differences in total leukocyte count, erythrocyte sedimentation rate, and neutrophil, monocyte, eosinophil, basophil, and lymphocyte counts were present between the No Gel or Van2 groups compared with the Gel control group, with the numbers available. CONCLUSION: The hydrogel coated on titanium implants, unloaded or loaded with 2% vancomycin, had no effect on the volume or timing of bone apposition near the implant, and did not induce an inflammatory reaction in vivo, with the numbers available. CLINICAL RELEVANCE: Antibiotic-loaded hydrogel may prove to be a valuable option to protect orthopaedic implants from bacterial colonization. Future clinical safety studies will need to provide more evidence that this product does not impair bone formation near the implant and prove the safety of this product