Infections Associated with Prosthetic Joints

Novel developments in the prevention, diagnosis, and treatment of periprosthetic joint infections

Periprosthetic joint infection (PJI) is one of the most challenging complications compromising the outcome of an otherwise successful operation. Considerable efforts have been invested in the recent years to address paradigm shifts in our understanding of the complex microbiological phenomena that contribute to the pathophysiology of PJI, such as microbial adherence, biofilm formation, and resistance to antibiotics. This article is an introduction to some of the recent advancements in the prevention, diagnosis, and treatment of PJI. It describes how industry, academic researchers, and government are increasing collaboration to address PJI through development of novel technologies, therapeutic strategies, and regulatory science that specifically target the unique biofilm-associated aspects of its pathogenesis.

Ten versus five polymorphonuclear leukocytes as threshold in frozen section tests for periprosthetic infection: a meta-analysis

We objectively appraised available evidence regarding the threshold for the number of polymorphonuclear leukocytes required in frozen section tests used to diagnose periprosthetic infection. Pooled summary estimates for sensitivity, specificity, positive likelihood ratio, negative likelihood ratio and diagnostic odds ratio (OR) were compared for ten and five polymorphonuclear leukocytes per high power field as the threshold. The total cohort included 1011 patients and the rate of infection was 19.2%. Although there was no difference in sensitivity or diagnostic OR, specificity was significantly higher for ten than for five polymorphonuclear leukocytes per high power field (p=0.007) In sum, a threshold of 10 polymorphonuclear leukocytes is better for diagnosing periprosthetic infections.

[Knee joint infections]

Knee joint infection represents an emergency case at every age. Joint infection occurs frequently after trauma or joint surgery. The infection can be caused by numerous bacteria, viruses, or yeasts; however, Staphylococcus aureus is identified as the cause in 85-95 % of joint infections. Early treatment is important for patient outcome. In addition to synovectomy and therapeutic arthroscopy, antibiotic therapy is essential and should be started after sample recovery.

Perioperative, postoperative, and prophylactic use of antibiotics in alloplastic total temporomandibular joint replacement surgery: a survey and preliminary guidelines

PURPOSE

In 2009, the American Academy Of Orthopedic Surgeons recommended lifelong prophylaxis after orthopedic total joint replacement (TJR) before these patients undergo dental, aerodigestive, genitourinary (GU), and gastrointestinal (GI) procedures. Because oral and maxillofacial surgeons worldwide are implanting alloplastic total temporomandibular joint replacements (TMJ TJRs), it appeared reasonable to survey these surgeons to obtain data that might shed some light, not only on this issue, but also to obtain some data to begin to develop preliminary guidelines for the peri- and postoperative use of antibiotics for TMJ TJR using these results and the orthopedic data.

MATERIALS AND METHODS

A total of 35 surgeons worldwide, members of either the TMJ Concepts or Biomet Microfixation online networks were e-mailed a standard questionnaire surveying their perioperative, postoperative, and prophylactic use of antibiotics for their TMJ TJR cases.

RESULTS

Of the 35 surgeons, 26 (74.2%) from 8 different countries responded. A total of 2,476 cases (3,368 joints) were retrospectively surveyed. Of the responding surgeons, 96.2% used, in order of frequency, cefazolin, clindamycin, cephalosporin, or penicillin-based antibiotics in the perioperative period and continued their use for a mean of 7 days (range 5 to 14) postoperatively. Also, 46.2% soaked the TJR components either in the perioperative antibiotic or in vancomycin, poviodine, gentamycin, or peroxide before implantation. In addition, 61.5% irrigated the wounds after device implantation with bacitracin, vancomycin, poviodine, peroxide, or the perioperative antibiotic. These surgeons reported that 51 joints (1.51%) had become infected within a mean of 6 months (range 2 weeks to 12 years) postoperatively. A total of 32 devices (0.95%) required removal and/or replacement. In cases in which the organisms were isolated, the organisms commonly associated with biofilm infection of TJR devices, Staphylococcus aureus, S epidermidis, Peptostreptococcus, and Pseudamonas aeruginosa, were cultured. In only 1 joint (0.003%) was there a suggestion of an association with an invasive dental/aerodigestive, GU/GI procedure. Regarding prophylaxis after TMJ TJRs and before dental/aerodigestive, GU, or GI procedures, 53.8% of the respondents reported that they provided prophylaxis. Of these, 1 recommended doing this for 6 months and 4 for 2 years, such as has been the American Dental Association/American Academy of Orthopedic Surgeons recommendation since 2003; and 9 reported they believe these TMJ TJR patients should have lifetime antibiotic prophylaxis before invasive dental/aerodigestive, GU, or GI procedures.

CONCLUSION

The evidence provided from the present small study survey and a review of the orthopedic data could provide the opportunity to develop guidelines for the preoperative, intraoperative, and postoperative antibiotic management for TMJ TJRs and spur additional research into this important area of patient management.

Bacterial adhesion, cell adhesion and biocompatibility of Nafion films

We investigated bioadhesion (bacterial and cell adhesion) and biocompatibility of poly(tetrafluoroethylene-co-perfluoro-3,6-dioxa-4-methyl-7-octenesulfonic acid) (Nafion) and compared the results with those obtained with poly(vinylidene fluoride-co-hexafluoropropylene) (PVFHFP). When incubated with bacteria for 4 h to 7 days, Nafion film exhibited scarce bacterial adhesion at 6 h, after which the adhesion gradually increasing to relatively low levels. In contrast, significant bacterial adhesion to PVFHFP film was observed at 4 h, and much higher adhesion levels were shown thereafter. Although HEp-2 human cells adhered normally to both films, reaching confluence in 7-8 days, the cells adhered to Nafion appeared more lively and stable than those to PVFHFP. Subcutaneous implantation in mice revealed that Nafion elicited a mild acute inflammatory reaction without chronic inflammation or tissue necrosis, indicating excellent biocompatibility in mice. PVFHFP, however, provoked a moderate and prolonged acute inflammatory response. These differences in the biological characteristics of Nafion and PVFHFP films may be attributable to the differences in the chemical and physical natures of these polymer films. Nafion film provided a sufficiently solid support, expressing a high surface charge density and good water-wettability. In summary, Nafion is suitable for use in biomedical applications that require biocompatibility with a reduced possibility of post-operative infections.

Reducing the risk of deep wound infection in primary joint arthroplasty with antibiotic bone cement

Despite significant advances in intraoperative antimicrobial procedures, deep wound infection remains the most serious complication associated with primary, cemented total joint arthroplasty. A systematic review was conducted to evaluate studies of antibiotic bone cement prophylaxis for reducing the risk of deep wound infection. The literature included 22 articles providing estimates of the prophylactic effectiveness of antibiotic cement. In reducing deep wound infection, antibiotic cement was consistently superior to plain cement, similar to systematic antiobiotics, and independent and additive in effect when combined with other prophylactic measures. Randomized controlled trials in particular had important methodological limitations. However, the collective results nearly unanimously favored prophylactic use of antibiotic cement in primary arthoplasty procedures.

Application of core biopsy in revision arthroplasty for deep infection

A preliminary core biopsy was performed in 168 consecutive joint arthroplasties (141 hips and 27 knees) before revision for suspected deep infection. Data of the core biopsy and subsequent revision procedures were available for 159 cases. Biopsies and revisions were all performed by one surgeon, and the exchange procedures were all undertaken in an ultra clean air enclosure. Biopsy material was cultured both aerobically and anaerobically and the results compared to that of the specimens obtained at the subsequent exchange procedure. In 116 patients (70%), the culture and sensitivity results were identical in samples from core biopsy and samples obtained during revision procedure (either no growth or growth of same organisms). When compared to intraoperative specimen report, 25 biopsies (15%) gave an apparently false-positive result. In 16 instances, a false-negative result was seen, but repeat biopsy in 4 of these cases was positive. The final diagnosis of infection was made using all available clinical and investigative data. When compared to final diagnosis, the sensitivity of core biopsy was 88%, the specificity was 91%, and the accuracy was 89%. Core biopsy was successful in identifying the organisms with the sensitivities to antibiotics in 80% of the disease-positive cases, hence, offering the opportunity to add the most appropriate antibiotic to bone cement during the exchange procedure.

Antibiotic prophylaxis for dental patients with total joint replacements

BACKGROUND AND OVERVIEW

In 1997, the American Dental Association and the American Academy of Orthopaedic Surgeons convened an expert panel of dentists, orthopaedic surgeons and infectious disease specialists and published their first Advisory Statement on Antibiotic Prophylaxis for Dental Patients with Prosthetic Joints. This represented the first time that national health organizations had gone on record on this topic. This 2003 advisory statement is the first periodic update of the 1997 statement. In addition, the organizations have created a new patient handout (included at the end of the statement) that dentists may share with their patients. The 1997 Advisory Statement has been well-used by dentists and orthopaedic surgeons. Following their standard protocols for periodic review of existing advisory statements, the ADA and AAOS and their expert consultants recently reviewed the 1997 statement.

CONCLUSIONS AND CLINICAL IMPLICATIONS

The 2003 statement includes some modifications of the classification of patients at potential risk and of the incidence stratification of bacteremic dental procedures, but no changes in terms of suggested antibiotics and antibiotic regimens. The statement concludes that antibiotic prophylaxis is not indicated for dental patients with pins, plates or screws, nor is it routinely indicated for most dental patients with total joint replacements. However, it is advisable to consider premedication in a small number of patients who may be at potential increased risk of experiencing hematogenous total joint infection.

Acute septic arthritis

Acute septic arthritis may develop as a result of hematogenous seeding, direct introduction, or extension from a contiguous focus of infection. The pathogenesis of acute septic arthritis is multifactorial and depends on the interaction of the host immune response and the adherence factors, toxins, and immunoavoidance strategies of the invading pathogen. Neisseria gonorrhoeae and Staphylococcus aureus are used in discussing the host-pathogen interaction in the pathogenesis of acute septic arthritis. While diagnosis rests on isolation of the bacterial species from synovial fluid samples, patient history, clinical presentation, laboratory findings, and imaging studies are also important. Acute nongonococcal septic arthritis is a medical emergency that can lead to significant morbidity and mortality. Therefore, prompt recognition, rapid and aggressive antimicrobial therapy, and surgical treatment are critical to ensuring a good prognosis. Even with prompt diagnosis and treatment, high mortality and morbidity rates still occur. In contrast, gonococcal arthritis is often successfully treated with antimicrobial therapy alone and demonstrates a very low rate of complications and an excellent prognosis for full return of normal joint function. In the case of prosthetic joint infections, the hardware must be eventually removed by a two-stage revision in order to cure the infection.

Cost-effectiveness of antibiotic prophylaxis for bacterial arthritis

The outcome of bacterial arthritis is generally poor: the mortality is 10 - 15% and there is loss of joint function in 25 - 50% of the survivors. The incidence of bacterial arthritis is low: 2 - 6 cases per 100,000 people per year. Risk factors are age, joint disease (especially rheumatoid arthritis [RA]), diabetes mellitus and the presence of a prosthetic joint. The predominant situations that can lead to bacterial arthritis are skin infections of the feet and rarely invasive medical or dental procedures. Due to the severity of the disease, antibiotic prophylaxis of haematogenous bacterial arthritis in patients with prosthetic joints is advocated. However, due to the rarity of the disease it is unclear whether the advantages of prophylaxis outweigh the disadvantages of the large-scale use of antibiotics, such as side effects, costs and bacterial resistance. In a decision-analysis of a large group of patients with joint diseases, antibiotic treatment of skin infections appeared to be cost-effective in the prevention of haematogenous bacterial arthritis, mainly in high-risk patients. On the other hand, prophylaxis around medical or dental procedures was not cost-effective, except possibly in a small group of patients with increased risk.

The role of intraoperative Gram stain in revision total joint arthroplasty

The ability to identify intraoperatively patients with an infected prosthesis at the time of a revision procedure assists the surgeon in selecting appropriate management. The results of 413 intraoperative Gram stains were compared with the results of operative cultures, permanent histology, and the surgeon's intraoperative assessment to determine the ability of Gram stains to identify periprosthetic infection. Gram staining correctly identified the presence of infection in 10 of the 68 cases that met study criteria for infection (sensitivity of 14.7%). Four false-positive Gram stains were encountered. Intraoperative Gram stains do not have adequate sensitivity to be helpful in identifying periprosthetic infection and should not be performed on a routine basis. They may be helpful, however, in cases in which gross purulence is encountered to assist in the selection of initial antibiotic therapy. The use of intraoperative Gram staining alone is inadequate for ruling out infection at the time of revision total joint arthroplasty.

Phenotypic and genomic variation among Staphylococcus epidermidis strains infecting joint prostheses

We studied the SmaI and SstII macrorestriction patterns of 54 Staphylococcus epidermidis strains isolated from 14 patients infected following the implantation of joint prostheses. Multiple strains from pus and infected tissue specimens of each patient were selected on the basis of different colony morphologies and drug resistance patterns. The same criteria were used to select 23 S. epidermidis strains from hand swabs of eight healthy individuals. For 10 of the 14 patients, all the intrapatient strains appeared to be closely or possibly related, whereas related strains were detected in the skin flora of only one of the eight healthy individuals. This observation suggests that, in most cases, the patients were infected by a single S. epidermidis clone which subsequently underwent rearrangements that yielded derivatives with divergent phenotypes and, occasionally, divergent macrorestriction patterns. The four patients whose specimens contained unrelated S. epidermidis strains were probably infected with several polyclonal strains.

Occurrence of HLA-B27 tissue antigen in patients with purulent arthritis caused by Staphylococcus aureus or beta-haemolytic streptococci

The HLA-B27 tissue antigen is associated with reactive arthritis caused by different bacterial infections but its occurrence in purulent arthritis has not been studied earlier. We analysed the frequency of HLA-B27 in patients with culture proven purulent arthritis caused by Staphylococcus aureus or beta-haemolytic streptococci. The study included 41 patients treated during the years 1979-96 (15 female and 26 male) with a mean age of 52 years (range 16-80 years). HLA-B27 was found in 24% (9/37) of the tested patients compared with 14% in the healthy Finnish population, but the difference was not statistically significant (P < 0.50). No statistical difference in disease activity according to febrile days or duration of the disease could be found between HLA-B27 positive and negative patients. We conclude that HLA-B27 is not a risk factor for purulent arthritis, and when present it has no significant modifying effect on the clinical picture of purulent arthritis.

Monitoring infective complications following hip fracture

Hip fracture affects more than 55,000 people in the UK each year and this number is increasing. Because of their advanced age and other risk factors, hip fracture patients are at risk of developing infection and a variety of other non-infective complications. Surveillance of superficial wound and deep joint infection is important because of the large number of patients involved and represents a good example of targeted surveillance. Furthermore this may be conducted as part of a quality control programme monitoring other interventions such as prophylaxis for vascular thrombosis. However, to carry this out successfully, a simple but efficient system for recording, collecting and analysing data is required and adequate post-discharge surveillance must be carried out.

Advisory statement. Antibiotic prophylaxis for dental patients with total joint replacements. American Dental Association; American Academy of Orthopaedic Surgeons

An expert panel of dentists, orthopaedic surgeons and infectious disease specialists convened by the American Dental Association and the American Academy of Orthopaedic Surgeons, or AAOS, performed a thorough review of all available data to determine the need for antibiotic prophylaxis to prevent hematogenous prosthetic joint infections in dental patients who have undergone total joint arthroplasties. The result is this report, which has been adopted by both organizations as an advisory statement. The panel's conclusion: Antibiotic prophylaxis is not indicated for dental patients with pins, plates and screws, nor is it routinely indicated for most dental patients with total joint replacements. However, it is advisable to consider premedication in a small number of patients who may be at potential increased risk of hematogenous total joint infection.

The outcome of bacterial arthritis: a prospective community-based study

OBJECTIVE

To assess the outcome and adverse prognostic factors of bacterial arthritis (BA).

METHODS

In a prospective community survey of BA, data were collected at the time of diagnosis and at a mean of 2 years later. A poor patient outcome was defined as death due to BA or severe overall functional deterioration. A poor joint outcome was defined as amputation, arthrodesis, prosthetic surgery, or severe functional deterioration. Possible prognostic factors were analyzed by univariate analysis.

RESULTS

BA was diagnosed in 154 patients, 121 adults and 33 children. One-half of the adults had a preexisting joint disease and 29% of the infected joints contained synthetic material. The patient outcome was poor in 21% of all patients, and the joint outcome was poor in 33% of the surviving patients. Adverse prognostic factors were an older age, preexisting joint disease, and an infected joint containing synthetic material. These factors were interrelated. There was no association between a poor outcome and young age, comorbidity, immunosuppressive medication, functional class, multiple infected joints, type of microorganism, or treatment delay.

CONCLUSION

BA had a poor outcome in almost one-half of the patients. Patients who were older, had a preexisting joint disease, and/or had an infected joint containing synthetic material had the poorest prognosis.

The reliability of analysis of intraoperative frozen sections for identifying active infection during revision hip or knee arthroplasty

A prospective study was performed to determine the reliability of analysis of intraoperative frozen sections for the identification of infection during 175 consecutive revision total joint arthroplasties (142 hip and thirty-three knee). The mean interval between the primary and the revision arthroplasty was 7.3 years (range, three months to twenty-three years). To reduce selections bias, tissue was obtained for frozen sections during all revisions in patients who did not have active drainage from the wound or a sinus tract. Of the 175 patients, twenty-three had at least five polymorphonuclear leukocytes per high-power field on analysis of the frozen sections and were considered to have an infection. Of these twenty-three, five had five to nine polymorphonuclear leukocytes per high-power field and eighteen had at least ten polymorphonuclear leukocytes per high-power field. The frozen sections for the remaining 152 patients were considered negative. On the basis of cultures of specimens obtained at the time of the revision operation, nineteen of the 175 patients were considered to have an infection. Of the 152 patients who had negative frozen sections, three were considered to have an infection on the basis of the results of the final cultures. Of the twenty-three patients who had positive frozen sections, sixteen were considered to have an infection on the basis of the results of the final cultures; all sixteen had frozen sections that had demonstrated at least ten polymorphonuclear leukocytes per high-power field. The sensitivity and specificity of the frozen sections were similar regardless of whether an index of five or ten polymorphonuclear leukocytes per high-power field was used. Analysis of the frozen sections had a sensitivity of 84 per cent for both indices, whereas the specificity was 96 per cent when the index was five polymorphonuclear leukocytes and 99 per cent when it was ten polymorphonuclear leukocytes. However, the positive predictive value of the frozen sections increased significantly (p < 0.05), from 70 to 89 per cent, when the index increased from five to ten polymorphonuclear leukocytes per high-power field. The negative predictive value of the frozen sections was 98 per cent for both indices. The current study suggests that it is valuable to obtain tissue for intraoperative frozen sections during revision hip and knee arthroplasty. At least ten polymorphonuclear leukocytes per high-power field was predictive of infection, while five to nine polymorphonuclear leukocytes per high-power field was not necessarily consistent with infection. Less than five polymorphonuclear leukocytes per high-power field reliably indicated the absence of infection.

The role of intraoperative frozen sections in revision total joint arthroplasty

We performed a retrospective analysis of thirty-three consecutive total hip and knee (twenty-three hip and ten knee) revision arthroplasties during which intraoperative frozen sections were analyzed. Data for the study were collected by means of a review of the charts, radiographic analysis, and evaluation of both frozen and permanent histological sections. The frozen sections, of periprosthetic tissue at the bone-cement interface or the pseudocapsule, were considered positive for active infection if there were more than five polymorphonuclear leukocytes per high-power field in at least five distinct microscopic fields. All patients were available for follow-up, at an average of thirty-six months (range, seventeen to seventy-nine months) after the initial revision operation. The frozen sections from ten patients were positive for infection, and those from twenty-three patients were negative. Comparison of the results of the analyses of the frozen sections (both positive and negative) with those of the analyses of the permanent histological sections of similar tissue showed a correlation of 100 per cent (sensitivity, 1.00; specificity, 1.00; and accuracy, 1.00). Nine patients had positive intraoperative cultures, and all of them had positive frozen sections (sensitivity, 1.00). Of the twenty-four patients who had negative intraoperative cultures, twenty-three had negative frozen sections (specificity, 0.96). Of the nine patients who had positive intraoperative cultures, only two were found to have infection on intraoperative gram-staining. The surgeon's operative assessment regarding the presence of infection, compared with the final pathological diagnosis, demonstrated a sensitivity of 0.70, a specificity of 0.87, and an accuracy of 0.82. All ten patients who had positive frozen sections were managed with excision arthroplasty; six of them subsequently had reimplantation, and the excision was the definitive procedure in the remaining four. One patient who had had a delayed reimplantation had a secondary skin slough and eventually was managed with an arthrodesis of the knee. In the group that had negative frozen sections, eighteen patients had a primary exchange revision arthroplasty and five had a delayed reimplantation. At the time of follow-up, one patient who had had a delayed reimplantation had radiographic loosening of the femoral component and was asymptomatic. One patient who had had a primary exchange arthroplasty was managed with a second revision because of aseptic loosening. There was no clinical recurrence of infection in any patient. The data indicate that analysis of frozen sections of periprosthetic tissue is a reliable predictor of the presence of active infection during revision joint arthroplasty. We recommend its use to differentiate aseptic from septic loosening.

Bacterial growth on antibiotic-loaded acrylic cement. A prospective in vivo retrieval study

Twenty-three patients with intraoperative culture-proven periprosthetic infection of the hip or knee were enrolled in a prospective cement retrieval study. All were treated with a two-stage technique using antibiotic-loaded acrylic cement as an antibiotic depot. Staphylococcus epidermidis was the most commonly isolated organism (19 of 23 cases). Cement and tissue were examined at second-stage revision for the presence of viable organisms. In this series, no organisms were isolated from the surface of the cement, a 100% concordance with the tissue cultures. A subsequent failure rate of 4.4% (1 case) was seen in this series. Investigation suggests this may represent reinfection from a new strain of organism rather than failure of eradication of the original infection.

Polymer materials for the prevention of catheter-related infections

Catheter-related infections are major problems in medicine because of severe consequences for the patient, prolongation of hospitalization, and increasing therapy costs. Beside progress in hygienic measures, development of catheters with antiinfective properties seems to be a promising approach to the prevention of such infections. Two approaches for infection-resistant catheter materials have been developed: materials with antiadhesive properties and materials with antimicrobial properties. Antiadhesive polymers shall prevent the adhesion of microorganisms to the medical device. However, up to now there has been no material which would lead to a complete inhibition of adherence ("zero adherence"). Materials with antimicrobial properties contain antimicrobial substances which are incorporated into the biomaterial or bound to the polymer surface. These devices seem to be effective in the prevention of "early onset infections". In this paper, an overview of the development and efficiency of antiadhesive or antimicrobial polymers is given.

Managing dental patients with joint prostheses

A literature review explored the possible association of late infections of major joint prostheses and dental bacteremias. The review showed transient dental bacteremias had little or no role in causing late infections of prosthetic joint replacements. However, patients with certain systemic conditions or complications with their prostheses may be at greater risk for infection after transient dental bacteremias.

An infected prosthetic hip. Is there a role for prophylactic antibiotics?

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Pyarthrosis in patients with rheumatoid arthritis: a report of 13 cases and a review of the literature from the past 40 years

PURPOSE

The purpose of this study is to report 13 cases and review the literature for pyarthrosis occurring in the setting of rheumatoid arthritis (RA). Special emphasis is placed on evaluating both the changing, as well as the constant, features of this complication and on assessing diagnostic and therapeutic aspects that have a bearing upon outcome.

PATIENTS AND METHODS

A retrospective review of records from our institution revealed 13 cases of pyarthrosis in patients with RA over the past 14 years. Information obtained included patient demographics, RA history, concomitant illnesses and medications, length of symptoms prior to the diagnosis of pyarthrosis, peri-articular manifestations, probable source of infection, joint(s) involved, relevant laboratory data, and information on treatment and outcome based on initial surgical therapy versus closed needle drainage. In addition, 213 cases from 45 citations were reviewed for similar information.

RESULTS

Our series was notable for a high percentage of associated serious medical illnesses and peri-articular manifestations of the pyarthrosis (i.e., sinus tract formation, concomitant septic bursitis, or infected synovial cyst). The erythrocyte sedimentation rate was a useful monitor of adequate therapy and was often a signal of recurrent infection. In all patients, the skin was the major source of infection. The mortality from pyarthrosis has declined over the past 40 years but is still unacceptably high, especially in patients with polyarticular involvement. Preliminary observations suggest that an initial surgical approach to joint drainage may be preferable to closed needle drainage in order to improve joint outcome in patients with RA and pyarthrosis.

CONCLUSION

Pyarthrosis occurring in patients with RA continues to produce unacceptable morbidity and mortality despite 40 years' experience. Earlier recognition (which may include peri-articular features) and perhaps an aggressive surgical approach to drainage may improve the prognosis.

Prophylactic use of phenoxymethylpenicillin and tinidazole in mandibular third molar surgery, a comparative placebo controlled clinical trial

A clinical double-blind placebo controlled trial was carried out in 136 patients to test the value of the prophylactic use of phenoxymethylpenicillin and tinidazole in mandibular third molar surgery. The three patient groups were uniform with regard to the background data such as age and weight of the patients and the clinical status of the operated tooth, as well as to the observations made at surgery. No statistically significant differences were found between the study groups in the parameters used for evaluation. The results indicate that neither penicillin nor tinidazole have more effect on postoperative complications following operative extraction of wisdom teeth, than placebo tablets.

Infection in total joint arthroplasty from distal intravenous lines. A case report

Prevention of late hematogenous infection of a total joint arthroplasty is of great importance because of the catastrophic consequences. Any situation that can lead to a bacteremia should be avoided and appropriate prophylactic antibiotics given in anticipation of a bacteremic episode. This report documents a bacteremia and total joint infection secondary to a routine intravenous line placed in an extremity distal to a total knee arthroplasty. Routine intravenous infusion lines should not be placed in extremities with proximal total joint arthroplasties. Educating both patients and physicians about the risks to a prosthetic joint is important.