Symposium: Papers Presented at the 2009 Meeting of the Musculoskeletal Infection Society 17 articles
Clinical characteristics and control of the infection of patients with culture-negative (CN) prosthetic joint infection (PJI) have not been well assessed. Prior use of antimicrobial therapy has been speculated but not proven as a risk factor for CNPJI.
Open orthopaedic wounds are ideal sites for infection. Preventing infection in these wounds is critical for reducing patient morbidity and mortality, controlling antimicrobial resistance and lowering the cost of treatment. Localized drug delivery has the potential to overcome the challenges associated with traditional systemic dosing. A degradable, biocompatible polymer sponge (chitosan) that can be loaded with clinician-selected antibiotics at the point of care would provide the patient and clinician with a desirable, adjunctive preventive modality.
Bone grafts are frequently used to supplement bone stock and to establish structural stability. However, graft-associated infection represents a challenging complication leading to increased patient morbidity and healthcare costs.
Deep infection remains one of the most devastating and costly complications after total knee arthroplasty (TKA). The risk of deep infection after revision TKA is reportedly greater than that for primary TKA; however, we do not know the exact incidence of infection after revision TKA.
Outcomes of Revision Total Knee Arthroplasty After Methicillin-resistant Staphylococcus aureus Infection
The incidence of infection by methicillin-resistant Staphylococcus aureus (MRSA) in total knee arthroplasty (TKA) is becoming a more frequent concern, as increased morbidity following TKA has been reported for infections by resistant organisms. This study investigates whether MRSA infections are associated with decreased functional scores.
We have previously described a unique gene expression signature exhibited by synovial fluid leukocytes in response to bacterial infection, identifying a number of potential biomarkers for infection. However, the diagnostic performance of these potential biomarkers in an immunoassay format is unknown.
Two-stage Exchange Knee Arthroplasty: Does Resistance of the Infecting Organism Influence the Outcome?
Periprosthetic joint infection after TKA is a challenging complication. Two-stage exchange arthroplasty is the accepted standard of care, but reported failure rates are increasing. It has been suggested this is due to the increased prevalence of methicillin-resistant infections.
Due to the historically poor infection control rates with débridement and component retention for acute periprosthetic infections we developed a new approach for treating acute periprosthetic total joint infections: initial débridement with prosthesis retention and placement of antibiotic-impregnated cement beads followed by a second débridement within 7 days, at which time the beads are removed and new modular parts inserted. Intravenous antibiotics were used for 6 weeks followed by oral antibiotics. Depending on the clinical situation, antibiotics are discontinued or in selected patients continued indefinitely.
Infections following hip and knee replacements can compromise the function and durability of arthroplasty. When these infections occur during the immediate postoperative period, irrigation and débridement can be attempted to salvage the implant. Prior studies have reported varying results likely due to lack of consistent inclusion criteria, variations in surgical technique, and lack of uniform treatment protocols.
An Approach for Determining Antibiotic Loading for a Physician-directed Antibiotic-loaded PMMA Bone Cement Formulation
When a physician-directed antibiotic-loaded polymethylmethacrylate (PMMA) bone cement (ALBC) formulation is used in total hip arthroplasties (THAs) and total knee arthroplasties (TKAs), current practice in the United States involves arbitrary choice of the antibiotic loading (herein defined as the ratio of the mass of the antibiotic added to the mass of the cement powder). We suggest there is a need to develop a rational method for determining this loading.
The literature contains variable reports on the causative organisms of osteomyelitis and septic arthritis in patients with injecting drug abuse and on the rate of oxacillin-resistant S aureus. It is important to have a clear notion of the organisms to initiate empiric antimicrobial therapy.
Biofilm formation on indwelling medical devices is a ubiquitous problem causing considerable patient morbidity and mortality. In orthopaedic surgery, this problem is exacerbated by the large number and variety of material types that are implanted. Metallic hardware in conjunction with polymethylmethacrylate (PMMA) bone cement is commonly used.
Adding soluble particulate poragens to antimicrobial-loaded bone cement increases the permeability of the bone cement and increases the antimicrobial release, but the mechanical effect of adding poragens is not well known.
Revision total hip arthroplasty (THA), although relieving pain and restoring function, fails in some patients. In contrast to failures in primary THA, the frequency of the causes of failure in revision THA has been less well established.