Bariatric Surgery Prior to Total Joint Arthroplasty, Does it Decrease the Risk of Obesity Related Perioperative Complications?

PURPOSE OF REVIEW: The purpose of this review paper is to provide an overview of the relationship between obesity, osteoarthritis, arthroplasty outcomes, and the potential use of bariatric surgery to improve these outcomes. RECENT FINDINGS: Unfortunately, the findings in the currently available literature evaluating the role of bariatric surgery prior to arthroplasty surgery largely rely on retrospective data and their results are somewhat conflicting. Future prospective studies are needed to further evaluate whether or not bariatric surgery prior to arthroplasty surgery may be of benefit for patients. Additional research is needed to identify other methods to minimize complications that obese patients are particularly prone to developing following arthroplasty surgery.

A comparison of the incidence of complications following total hip arthroplasty in patients with or without osteonecrosis.

Osteonecrosis (ON) is a common cause of hip arthritis requiring arthroplasty (THA). ON patients often have associated conditions that place them at a greater risk for complications. The aim of this study is to determine complication rates of ON versus other THA patients. Statewide hospital admissions for THA were identified (1995-2010). THA procedures and ON diagnosis were identified using ICD-9 codes. Logistic regression analysis was used to determine the role of ON as a predictor of complications. ON led to an increased risk of sepsis and readmission. There was no significant difference in mortality rate. This study demonstrates that patients with ON undergoing THA have increased rates of readmission and sepsis. These findings are helpful in allocating resources for treating this patient group.

Controlled Release of Vancomycin and Tigecycline from an Orthopaedic Implant Coating Prevents Staphylococcus aureus Infection in an Open Fracture Animal Model.

INTRODUCTION: Treatment of open fractures routinely involves multiple surgeries and delayed definitive fracture fixation because of concern for infection. If implants were made less susceptible to infection, a one-stage procedure with intramedullary nailing would be more feasible, which would reduce morbidity and improve outcomes. METHODS: In this study, a novel open fracture mouse model was developed using Staphylococcus aureus (S. aureus) and single-stage intramedullary fixation. The model was used to evaluate whether implants coated with a novel "smart" polymer coating containing vancomycin or tigecycline would be colonized by bacteria in an open fracture model infected with S. aureus. In vivo bioluminescence, ex vivo CFUs, and X-ray images were evaluated over a 42-day postoperative period. RESULTS: We found evidence of a markedly decreased bacterial burden with the local release of vancomycin and tigecycline from the PEG-PPS polymer compared to polymer alone. Vancomycin was released in a controlled fashion and maintained local drug concentrations above the minimum inhibition concentration for S. aureus for greater than 7 days postoperatively. Bacteria were reduced 139-fold from implants containing vancomycin and undetected from the bone and soft tissue. Tigecycline coatings led to a 5991-fold reduction in bacteria isolated from bone and soft tissue and 15-fold reduction on the implants compared to polymer alone. Antibiotic coatings also prevented osteomyelitis and implant loosening as observed on X-ray. CONCLUSION: Vancomycin and tigecycline can be encapsulated in a polymer coating and released over time to maintain therapeutic levels during the perioperative period. Our results suggest that antibiotic coatings can be used to prevent implant infection and osteomyelitis in the setting of open fracture. This novel open fracture mouse model can be used as a powerful in vivo preclinical tool to evaluate and optimize the treatment of open fractures before further studies in humans.

Current Animal Models of Postoperative Spine Infection and Potential Future Advances.

Implant related infection following spine surgery is a devastating complication for patients and can potentially lead to significant neurological compromise, disability, morbidity, and even mortality. This paper provides an overview of the existing animal models of postoperative spine infection and highlights the strengths and weaknesses of each model. In addition, there is discussion regarding potential modifications to these animal models to better evaluate preventative and treatment strategies for this challenging complication. Current models are effective in simulating surgical procedures but fail to evaluate infection longitudinally using multiple techniques. Potential future modifications to these models include using advanced imaging technologies to evaluate infection, use of bioluminescent bacterial species, and testing of novel treatment strategies against multiple bacterial strains. There is potential to establish a postoperative spine infection model using smaller animals, such as mice, as these would be a more cost-effective screening tool for potential therapeutic interventions.