Blood cultures for evaluation of fever after total joint arthroplasty.

Fever after total joint arthroplasty (TJA) is common. Fearing the potential complications of bacteremia, physicians often obtain blood cultures to evaluate fever after TJA. In this study, we retrospectively examined the results of 102 sets (204 samples) of blood cultures that had been obtained from 50 patients (mean age, 67.3 years) during the first 2 postoperative days for evaluation of fever of 38.3 degrees C or higher. All patients had been receiving antibiotic prophylaxis. Of the 50 patients, 39 had undergone total knee arthroplasty, and 11 had undergone total hip arthroplasty. There had been 49 primary operations and 1 revision. Of the 204 blood culture samples, none had grown a pathogen. The cultures had been ordered by both surgical (61%) and medical (39%) services. The 2008 institution charge to process the 2 blood culture samples (1 set) routinely collected for each evaluation was $120 (true cost, $44.29). Therefore, in the current healthcare market, the charge to the payer for processing 102 sets would be $12,240. We conclude that blood cultures are neither useful nor cost-effective in evaluating fever immediately after TJA. We believe that the results of this study will be helpful to both orthopedists and medical consultants involved in the care of TJA patients.

Smoking and socio-economic status in the etiology and severity of Legg-Calvé-Perthes' disease.

BACKGROUND: The etiology of Legg-Calvé-Perthes disease is poorly understood. An association has been found in the past between Legg-Calvé-Perthes disease and smoking as well as low socio-economic status. METHODS: A prospective study was carried out in which families with a child diagnosed with Legg-Calvé-Perthes' disease were interviewed about the presence and duration of household second-hand smoke exposure to children. A control group of randomly selected families seen at our institution were interviewed with identical questions. The radiographs of children with Legg-Calvé-Perthes disease were reviewed and classified according to the Herring lateral pillar classification system. RESULTS: Thirty-eight of the 60 patients (63.3%) with Legg-Calvé-Perthes disease were noted to have at least one smoker living in the child's household with a mean of 1.03 smoker-years per year of life exposure to smoke. The median income of the patients with Legg-Calvé-Perthes disease was USD 20,300. The median income of the patients in the control group was USD 17,000. Thirty-eight of the 96 control patients (39.6%) were noted to have at least one smoker living in the child's household with a mean of 0.48 smoker-years per year of life. A significant association was noted between living with a smoker and Legg-Calvé-Perthes disease as well as between increasing smoke exposure and increased risk of developing Legg-Calvé-Perthes disease. No significant association was noted between lower income and Legg-Calvé-Perthes disease. There was no association between increased smoke exposure and increased severity of Legg-Calvé-Perthes disease as measured by the lateral pillar classification. CONCLUSIONS: The presence of second-hand smoke seems to be a significant risk factor in the development of Legg-Calvé-Perthes disease. The presence of second-hand smoke may represent the 'unknown industrial factor' that has been discussed.