Silver carboxylate-TiO2/polydimethyl siloxane is a safe and effective antimicrobial with significant wound care potential.

Introduction: With the rise in antibiotic resistance, new methodologies are needed to combat musculoskeletal infections. Silver is an antimicrobial that can be synthesized in different forms, but its pharmacokinetics are difficult to control. This study details the antibacterial efficacy and cellular cytotoxicity of a formulation consisting of silver carboxylate (AgCar) released through a titanium dioxide/polydimethylsiloxane matrix with a predictable release profile on Pseudomonas aeruginosa, Acinetobacterium baumannii, and human-derived primary osteoblasts. Methods: Through an Institutional Animal Care and Use Committee and IRB-approved protocol, AgCar was applied to live Yucatan porcine skin and histologically analyzed for skin penetration. Graphite Furnace Atomic Absorption Spectroscopy (GFAAS) was used to measure elution of AgCar. Dose-response curves were generated through optical density to assess potency. Finally, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was used to quantify the cellular cytotoxicity of the novel formulation. The results were subject to statistical analysis using analysis of variance and post hoc Tukey tests. Results: The silver carboxylate coating demonstrated deep penetration into the epithelium at the level of the deep pilosebaceous glands in animal models. GFAAS testing demonstrated the extended elution profile of silver carboxylate over 96 hours, while 100% silver with no titanium dioxide-polydimethylsiloxane matrix fully eluted within 48 hours. 10x silver carboxylate demonstrated superior antimicrobial activity to antibiotics and other silver formulations and showed minimal cytotoxicity compared with other silver formulations. Discussion/Clinical Relevance: Current antimicrobial therapies in wound care and surgical antisepsis, such as chlorhexidine gluconate, have pitfalls including poor skin penetration and short duration of efficacy. The broad antimicrobial activity, extended elution, and deep skin penetration of this AgCar formulation show great promise for surgical site infection and wound care treatment. Novel technology to fight the growing threat of microbial resistance should be at the forefront of orthopaedic surgical site infection prevention and treatment.

Prospectively Collected Comparison of Outcomes Between Surgically and Conservatively Treated Patients with Adolescent Idiopathic Scoliosis.

STUDY DESIGN: Retrospective review of a prospectively collected multicenter registry. OBJECTIVE: To evaluate health-related quality of life (HRQOL) measures in an operative cohort of patients (OP) and compare them with a matched nonoperative cohort (NON). SUMMARY OF BACKGROUND DATA: Historically, the surgical outcomes of adolescent idiopathic scoliosis (AIS) have been radiographically evaluated. However, the importance of HRQOL measures and their impact on surgical outcomes are increasingly being understood. METHODS: We identified 90 NON patients with curves in the operative range who were observed for at least 2 years. These patients were matched with an OP cohort of 689 patients. All patients completed the Scoliosis Research Society-22 (SRS-22) questionnaire at the initial evaluation and at a minimum of 2-year follow-up. Subgroup comparisons were based on curve type: primary thoracic (Th), primary thoracolumbar/lumbar (TL/L), and double major (DM) curves. RESULTS: The preoperative major curves in the Th, TL/L, and DM OP subgroups averaged 50.4°, 45.4°, and 51.5°, respectively, and 49.4°, 43.7°, and 48.9° in the NON cohort (P > 0.05). At 2 years postoperatively, the major curve in the Th, TL/L, and DM OP subgroups improved to 19.0°, 19.2°, and 19.3°, respectively, compared to the progression to 51.3°, 44.5°, and 49.7° in the NON group at 2-year follow-up (P < 0.05). The SRS-22 self-image, mental health, satisfaction, and total scores at the 2-year follow-up were significantly better in all OP subgroups (P < 0.001) but remained largely unchanged in the NON group. A significant percentage of patients (P < 0.001) in the OP cohort reported better SRS-22 scores at the 2-year follow-up in the self-image, mental health, and satisfaction domains than the NON group at 2 years. CONCLUSIONS: Surgically treated patients with AIS have improved HRQOL outcomes in several domains compared to age- and curve magnitude-matched nonoperatively treated patients at 2-year follow-up.

Nonsurgical Interventional Spine Pain Procedures: Outcomes and Complications.

¼: Nonsurgical interventional spine pain procedures provide an additional treatment option for lower back pain at the traditional bifurcation of conversative vs. operative management. ¼: Transforaminal epidural steroid injections, radiofrequency ablations, intrathecal drug delivery, and spinal cord stimulation were found to be effective and safe techniques when applied to their specific indication. ¼: Thermal annuloplasty and minimally invasive lumbar decompression showed mixed support. ¼: Discography, sacroiliac joint injections, and spinous process spacers lacked sufficient evidence to support efficacy. ¼: Medial branch blocks and facet joint injections were found to be useful diagnostic tools.

Silver Carboxylate-Eluting Titanium-Dioxide Polydimethylsiloxane Coating Inhibits Multi-Drug-Resistant Acinetobacterium baumannii and Vancomycin-Resistant Enterococcus faecalis Adherence and Proliferation on Orthopedic Trauma Fixation and Spinal Fusion Materials.

Background: Vancomycin-resistant Enterococcus faecalis and multi-drug-resistant (MDR) Acinetobacter baumannii are rising contributors to spinal fusion and fracture-associated infections (FAI), respectively. These MDR bacteria can form protective biofilms, complicating traditional antibiotic treatment. This study explores the effects of the antibiotic-independent antimicrobial silver carboxylate (AgCar)-doped coating on the adherence sand proliferation of these pathogens on orthopedic implant materials utilized in spinal fusion and orthopedic trauma fixation. Methods: Multi-drug-resistant Acinetobacter baumannii and vancomycin-resistant Enterococcus faecalis were inoculated on five common implant materials: cobalt chromium, titanium, titanium alloy, polyether ether ketone, and stainless steel. Dose response curves were generated to assess antimicrobial potency. Scanning electron microscopy and confocal laser scanning microscopy were utilized to characterize and quantify growth and adherence on each material. Results: The optimal AgCar concentration was a 95% titanium dioxide (TiO2)-5% polydimethylsiloxane (PDMS) matrix combined with 10 × silver carboxylate, which inhibited bacterial proliferation by 89.40% (p = 0.001) for MDR Acinetobacter baumannii and 84.02% (p = 0.001) for vancomycin-resistant Enterococcus faecalis compared with uncoated implants. A 95% TiO2-5% PDMS matrix combined with 10 × AgCar was equally effective at inhibiting bacterial proliferation across all implant materials for MDR Acinetobacter baumannii (p = 0.19) and vancomycin-resistant Enterococcus faecalis (p = 0.07). A 95% TiO2-5% PDMS matrix with 10 × AgCar is effective at decreasing bacterial adherence of both MDR Acinetobacter baumannii and vancomycin-resistant Enterococcus faecalis on implant materials. Conclusions: Application of this antibiotic-independent coating for surgery in which these implant materials might be used may prevent adherence, biofilm formation, spinal infections, and FAI by MDR Acinetobacter baumannii and vancomycin-resistant Enterococcus faecalis.

Silver as an Antibiotic-Independent Antimicrobial: Review of Current Formulations and Clinical Relevance.

Background: The increase of multi-drug-resistant organisms has revived the use of silver as an alternative antibiotic-independent antimicrobial. Although silver's multimodal mechanism of action provides low risk for bacterial resistance, high local and uncontrolled concentrations have shown toxicity. This has resulted in efforts to develop novel silver formulations that are safer and more predictable in their application. Optimization of silver as an antimicrobial is crucial given the growing resistance profile against antibiotics. This article reviews formulations of silver used as antimicrobials, focusing on the mechanisms of action, potential for toxicity, and clinical applications. Methods: A search of four electronic databases (PubMed, Embase, MEDLINE, and Cochrane Library) was conducted for relevant studies up to January 2022. Searches were conducted for the following types of silver: ionic, nanoparticles, colloidal, silver nitrate, silver sulfadiazine, silver oxide, silver carboxylate, and AQUACEL® (ConvaTec, Berkshire, UK). Sources were compiled based on title and abstract and screened for inclusion based on relevance and study design. Results: A review of the antimicrobial activity and uses of ionic silver, silver nanoparticles, colloidal silver, silver nitrate, silver sulfadiazine, silver oxide, Aquacel, and silver carboxylate was conducted. The mechanisms of action, clinical uses, and potential for toxicity were studied, and general trends between earlier and more advanced formulations noted. Conclusions: Early forms of silver have more limited utility because of their uncontrolled release of silver ions and potential for systemic toxicity. Multiple new formulations show promise; however, there is a need for more prospective in vivo studies to validate the clinical potential of these formulations.

Silver Carboxylate as an Antibiotic-Independent Antimicrobial: A Review of Current Formulations, in vitro Efficacy, and Clinical Relevance.

The increasing prevalence of multi-drug resistant pathogens has led to a renewed focus on the use of silver as an antibiotic-independent antimicrobial. Unfortunately, the use of many silver formulations may be limited by an uncontrolled release of silver with the potential for significant cytotoxic effects. Silver carboxylate (AgCar) has emerged as an alternative formulation of silver with the potential to mitigate these concerns while still displaying significant bactericidal activity. This article reviews the efficacy of silver carboxylate formulations as a promising novel antibiotic-independent antimicrobial. This study was conducted through a search of five electronic databases (PubMed, Embase, MEDLINE, Cochrane Library, and Web of Science) for relevant studies up to September 2022. Searches were conducted for types of "silver carboxylate" formulations. Sources were compiled based on title and abstract and screened for inclusion based on relevance and study design. A review of the antimicrobial activity and cytotoxicity of silver carboxylate was compiled based on this search. Current body of data suggests that silver carboxylate shows promise as an emerging antibiotic-independent antimicrobial, with significant bactericidal effects while minimizing cytotoxicity. Silver carboxylate addresses several of the limitations of more primitive formulations, including controlled dosing and fewer negative effects on eukaryotic cell lines. These factors are concentration-dependent and largely rely on the vehicle system used to deliver it. Although several silver carboxylate-based formulations like titanium dioxide/polydimethylsiloxane (TiO2/PDMS) matrix-eluting AgCar have shown promising results in vitro, and could potentially be utilized independently or in conjunction with current and future antimicrobial therapies, there is a need for further in vivo studies to validate their overall safety and efficacy profile.

Imaging and Laboratory Workup for Hand Infections.

Hand infections can lead to significant morbidity if not treated promptly. Most of these infections, such as abscesses, tenosynovitis, cellulitis, and necrotizing fasciitis, can be diagnosed clinically. Laboratory values, such as white blood cell count, erythrocyte sedimentation rate, C-reactive protein, and recently, procalcitonin and interleukin-6, are helpful in supporting the diagnosis and trending disease progression. Radiographs should be obtained in all cases of infection. Ultrasound is a dynamic study that can provide quick evaluation of deeper structures but is operator dependent. Computed tomographic and MRI studies are useful for evaluating deep space or bony infections and preoperative surgical planning.

Length of stay and 30-day readmissions after isolated humeral shaft fracture open reduction and internal fixation compared to intramedullary nailing.

INTRODUCTION: Open reduction with internal fixation (ORIF) and intramedullary nailing (IMN) have similar union rates for treating humerus shaft fractures, but IMN leads to increased incidence of shoulder impingement and reoperation. The difference in 30-day readmission rate and length of stay (LOS) between these procedures is unknown. The objective of the study was to compare 30-day unplanned readmissions and length of stay between humeral shaft fractures fixed with either ORIF or IMN. METHODS: The nationwide readmissions database (NRD) was queried for patients with humeral shaft fractures treated with ORIF or IMN between 2015-2016. IMN cases were propensity matched to ORIF cases based on demographic and co-morbid variables. Multivariable logistic regression determined if treatment modality was an independent risk factor for 30-day readmission or length of stay >3 days. RESULTS: There were 406 patients treated with IMN matched to 406 patients treated with ORIF. The 30-day readmission rate was 6.4% for IMN and 4.9% for ORIF (p = 0.45), and the median LOS was 3 days for each group (p = 0.45). Congestive heart failure (CHF)(OR=2.7, p = 0.04), depression (OR=3.3, p = 0.0008), and electrolyte abnormality (OR=3.6, p = 0.0003) were independent risk factors for readmission. Older age (OR=1.02, p = 0.03), CHF (OR=2.4, p = 0.03), electrolyte abnormality (OR=2.6, p = 0.0001), obesity (OR=2.8, p<0.0001), Medicaid (OR=2.1, p = 0.04), discharge to a facility (OR = 5.2, p<0.0001), discharge with home health services (OR=2.4, p = 0.0003), and open fracture (OR=2.3, p = 0.01) were independent risk factors for LOS >3 days. Procedure (ORIF vs. IMN) was not a predictor of 30-day readmission or LOS >3 days. CONCLUSION: Comorbid conditions are risk factors for 30-day readmission and increased LOS. Comorbidity, discharge disposition, and open fractures are risk factors for increased LOS. Treating humeral shaft fractures with either ORIF or IMN did not affect readmission or length of stay.

Current Concepts in Talar Neck Fracture Management.

PURPOSE OF THE REVIEW: Talar neck fractures are a rare but potentially devastating injury, which require a comprehensive understanding of the unique osteology, vasculature, and surrounding anatomy to recognize pathology and treat correctly. The purpose of this article is to describe both classic and current literature to better understand the evolution of talar neck fracture management. RECENT FINDINGS: Urgent reduction of displaced fractures and dislocations remains the standard of care to protect the soft tissue envelope and neurovascular structures. Delayed definitive fixation has proven to be safe. CT is the imaging modality of choice to fully identify the fracture pattern and associated injuries. Anatomic reduction and restoration of the peritalar articular surfaces are the pillars of talar neck fracture treatment. Dual incision approach with plate and screw fixation has become the modern surgical strategy of choice to accomplish these goals. Although complications such as osteonecrosis (ON) and posttraumatic arthritis (PTA) can still occur at high rates, treatment should be dictated by patient symptoms. Talar neck fractures pose treatment challenges with both initial injury and potential sequelae. Future research will determine whether modern treatment algorithms will decrease complication rate and improve patient outcome.

Predictors of the need for critical care after total joint arthroplasty: an update of our institutional risk stratification model.

Based on our previously published risk stratification model, 295 (19%) of a consecutive series of 1594 TJA patients were triaged to the ICU. However, only 67 patients (22%) required intensive care interventions. We identified 5 independent multivariate predictors (P < 0.001) including COPD, CAD, CHF (1 point each), EBL > 1000 mL, and intraoperative vasopressors (2 points each) to form the Penn Arthroplasty Risk Score (PARS). Patients with a score of 0 through 7 had a probability of requiring critical care of 7.0%, 13.2%, 23.5%, 38.1%, 55.4%, 71.4%, 83.4%, and 91.1% respectively. Based on these results, our previous risk stratification protocol is overly sensitive and non-specific. Any risk stratification algorithm for ICU admission should include intraoperative risk factors in order to be fully predictive.