Implementation of Preoperative Screening Criteria Lowers Infection and Complication Rates Following Elective Total Hip Arthroplasty and Total Knee Arthroplasty in a Veteran Population.

BACKGROUND: Total hip arthroplasty (THA) and total knee arthroplasty (TKA) are common procedures with a risk of complications. Attempting to minimize complications, our institution implemented preoperative screening criteria for patients undergoing elective total joint replacement. Our study aimed to determine if screening criteria lowered total complications and/or surgical site infections (SSI). METHODS: Two groups of consecutive patients undergoing TKA and THA at a single Veterans Affairs facility were evaluated prior to and after implementation of screening criteria, 520 and 475 respectively. Screening criteria included hemoglobin A1c ≤7, hemoglobin ≥11, body mass index ≤35, and albumin ≥3.5. Groups were analyzed for demographics, preoperative comorbidities, and postoperative complications. Rates of total complications and SSI were compared. Average follow-up was at least 2 years with minimum of 1 year. RESULTS: Demographics and comorbidities outside the screening criteria were similar. Total complication rate was reduced from 35.4% to 14.8% (P < .01) after implementation of screening criteria. For TKA, total complications were reduced from 33.1% to 15.0% (P < .01) and for THA they were reduced from 42.4% to 14.2% (P < .01). SSI rates for combined TKA and THA were reduced from 4.4% to 1.3% (P < .01). For knees, SSI was reduced from 4.6% to 1.3% (P = .01) and was statistically significant. For THA, SSI decreased from 3.8% to 1.2% (P < .05). CONCLUSION: Our institution saw a statistically significant decrease in both SSI and total complications following implementation of preoperative screening criteria for elective TKA and THA.

Use of perfusion- and diffusion-weighted imaging in differential diagnosis of acute and chronic ischemic stroke and multiple sclerosis.

OBJECTIVE: To investigate differences in lesions and surrounding normal appearing white matter (NAWM) by perfusion-weighted imaging (PWI) and diffusion-weighted imaging (DWI) in patients with acute and chronic ischemic stroke and multiple sclerosis (MS). METHODS: Study subjects included 45 MS patients, 22 patients with acute ischemic stroke and 20 patients with chronic ischemic stroke. All subjects underwent T2-weighted imaging (WI), flair attenuated inversion recovery (FLAIR), DWI and dynamic contrast enhanced PWI. Apparent diffusion coefficient (ADC) and mean transit time (MTT) maps were generated and values were calculated in the acute and chronic ischemic and demyelinating lesions, and in NAWM for distances of 5, 10 and 15 mm. Fifty-three acute ischemic and 33 acute demyelinating lesions, and 775 chronic ischemic and 998 chronic demyelinating lesions, were examined. Univariate, multivariate and data mining analyses were used to examine the feasibility of a prediction model between different lesion types. Correctly and incorrectly classified lesions, true positive (TP), false positive (FP) and precision rates were calculated. RESULTS: Patients with acute ischemic lesions presented more prolonged mean MTT values in lesions (p=0.002) and surrounding NAWM for distances of 5, 10 and 15 mm (all p<0.0001) than those with acute demyelinating lesions. In multinomial logistic regression analysis, 65 of 86 acute lesions were correctly classified (75.6%). The TP rates were 81.1% for acute ischemic lesions and 66.7% for acute demyelinating lesions. The FP rates were 33.3% for acute ischemic and 18.9% for acute demyelinating lesions. The precision was 79.6% for classification of acute ischemic lesions and 68.8% for prediction of acute demyelinating lesions. The logistic model tree decision algorithm revealed that prolonged MTT of surrounding NAWM for a distance of 15 mm (> or =7459.2 ms) was the best classifier of acute ischemic versus acute demyelinating lesions. Patients with chronic ischemic lesions presented higher mean ADC (p<0.0001) and prolonged MTT (p=0.013) in lesions, and in surrounding NAWM for distances of 5, 10 and 15 mm (all p<0.0001), compared to the patients with chronic demyelinating lesions. Data mining analyses did not show reliable predictability for correctly discerning between chronic ischemic and chronic demyelinating lesions. The precision was 56.7% for classification of chronic ischemic and 58.9% for prediction of chronic demyelinating lesions. DISCUSSION: We found prolonged MTT values in lesions and surrounding NAWM of patients with acute and chronic ischemic stroke when compared to MS patients. The use of PWI is a promising tool for differential diagnosis between acute ischemic and acute demyelinating lesions. The results of this study contribute to a better understanding of the extent of hemodynamic abnormalities in lesions and surrounding NAWM in patients with MS.

Anatomic Knowledge and Perceptions of the Adequacy of Anatomic Education Among Applicants to Orthopaedic Residency.

BACKGROUND: The time dedicated to the study of human anatomy within medical school curriculums has been substantially reduced. The effect of this on the knowledge of incoming orthopaedic trainees is unknown. The current study aimed to evaluate both the subjective perceptions and objective anatomic knowledge of fourth-year medical students applying for orthopaedic residency. METHODS: A multicenter prospective study was performed that assessed 224 students during the course of their interview day for an orthopaedic residency. Participants provided demographic data and a subjective assessment of the quality of their anatomic education, and completed either an upper or lower extremity anatomic examination. Mean total scores and subscores for various anatomic regions and concepts were calculated. RESULTS: Students on average rated the adequacy of their anatomic education as 6.5 on a 10-point scale. Similarly, they rated the level of importance their medical school placed on anatomic education as 6.2 on a 10-point scale. Almost 90% rated the time dedicated to anatomy as good or fair. Of six possible methods for learning anatomy, dissection was rated the highest.On objective examinations, the mean score for correct answers was 44.2%. This improved to 56.4% when correct and acceptable answers were considered. Regardless of anatomic regions or concepts evaluated, percent correct scores did not reach 50%. There were no significant correlations between performance on the anatomic examinations and either prior academic performance measures or the student's subjective assessment of their anatomic education. CONCLUSIONS: Current students applying into orthopaedic residency do not appear to be adequately prepared with the prerequisite anatomic knowledge. These deficits must be explicitly addressed during residency training to produce competent, safe orthopaedic surgeons.

Tumor angiogenesis: insights and innovations.

Angiogenesis is a vital process resulting in the formation of new blood vessels. It is normally a highly regulated process that occurs during human development, reproduction, and wound repair. However, angiogenesis can also become a fundamental pathogenic process found in cancer and several other diseases. To date, the inhibition of angiogenesis has been researched at both the bench and the bedside. While several studies have found moderate improvements when treating with angiogenesis inhibitors, greater success is being seen when the inhibition of angiogenesis is combined with other traditional forms of available therapy. This review summarizes several important angiogenic factors, examines new research and ongoing clinical trials for such factors, and attempts to explain how this new knowledge may be applied in the fight against cancer and other angiogenic-related diseases.