Prevalence, Timing, Causes, and Outcomes of Hyponatremia in Hospitalized Orthopaedic Surgery Patients.

BACKGROUND: Hyponatremia is common among orthopaedic patients and is associated with adverse clinical outcomes. We examined the prevalence, timing, causes, and outcomes of hyponatremia in adult hospitalized orthopaedic surgery patients. METHODS: We evaluated the medical records of 1067 consecutive orthopaedic surgery patients admitted to a tertiary academic institution. The medical records were reviewed to investigate hyponatremia (serum sodium <135 mEq/L) that (1) had been present on hospital admission or (2) had developed postoperatively. The primary outcomes were the prevalence and timing of, and risk factors for, presentation with or development of hyponatremia. Secondary outcomes were hospital length of stay, total hospital cost, and discharge disposition. Multivariable logistic regression models were used to assess the variables associated with hyponatremia and the effects of hyponatremia on clinical outcomes. RESULTS: Of the 1067 patients, seventy-one (7%) had preoperative hyponatremia and 319 (30%) developed hyponatremia postoperatively. Of the latter, 298 (93%) developed hyponatremia within forty-eight hours postoperatively. Compared with patients with normonatremia, those who presented with hyponatremia, on the average, were older (67.2 versus 60.5 years, p < 0.001), had longer hospital stays (4.6 versus 3.3 days, p < 0.001), incurred higher hospital costs ($19,200 versus $17,000, p = 0.006), and were more likely to be discharged to an extended-care facility (odds ratio [OR] = 2.87, p < 0.001). Developing hyponatremia postoperatively resulted, on average, in a longer hospital stay (3.7 versus 3.3 days, p = 0.002) and greater hospital cost ($18,800 versus $17,000, p < 0.001). Age (OR = 1.13 per decade, p = 0.012), spine surgery (OR = 2.76 versus knee, p < 0.001), hip surgery (OR = 1.76 versus knee, p < 0.001), and the amount of lactated Ringer solution used (OR = 1.16, p = 0.002) increased the risk of developing hyponatremia. CONCLUSIONS: Hyponatremia in orthopaedic patients is associated with longer, costlier hospitalizations. The factors that significantly increased the risk of developing postoperative hyponatremia were an older age, spine fusion, hip arthroplasty, and the amount of lactated Ringer solution used.

Ankle arthritis: review of diagnosis and operative management.

The diagnostic and therapeutic options for ankle arthritis are reviewed. The current standard of care for nonoperative options include the use of nonsteroidal antiinflammatory drugs, corticosteroid injections, orthotics, and ankle braces. Other modalities lack high-quality research studies to delineate their appropriateness and effectiveness. The gold standard for operative intervention in end-stage degenerative arthritis remains arthrodesis, but evidence for the superiority in functional outcomes of total ankle arthroplasty is increasing. The next few years will enable more informed decisions and, with more prospective high-quality studies, the most appropriate patient population for total ankle arthroplasty can be identified.

An assessment of musculoskeletal knowledge in graduating medical and physician assistant students and implications for musculoskeletal care providers.

BACKGROUND: The purpose of the present study was to evaluate musculoskeletal knowledge among graduating medical students and physician assistant students with use of a National Board of Medical Examiners (NBME) examination. We hypothesized that there would be no difference in scores between the two groups. In addition, we looked for relationships between examination scores and both the student-reported musculoskeletal experiences and the school-reported musculoskeletal curriculum. METHODS: One hundred and forty-four students from three medical schools and ninety-one students from four physician assistant schools were included in the present study; both groups were graduating students in the final semester of education. The National Board of Medical Examiners Musculoskeletal Subject Examination (NBME MSK) was utilized to assess musculoskeletal knowledge. RESULTS: The mean examination score (and standard deviation) was 73.8% ± 9.7% for medical students and 62.3% ± 11% for physician assistant students (95% confidence interval [CI], -13.8 to 0.00; p < 0.05). Medical students with an interest in orthopaedics as a career scored significantly higher than those without an expressed orthopaedic interest, and medical students without an expressed career interest in orthopaedics scored significantly higher than physician assistant students (p < 0.05). Among medical students, a longer duration of a clinical rotation in orthopaedics was associated with a higher examination score (p < 0.05). The average number of hours of preclinical musculoskeletal education in the first two years of school was significantly higher for medical schools (122.1 ± 25.1 hours) than for physician assistant schools (89.8 ± 74.8 hours) (p < 0.05). CONCLUSIONS: Graduating medical students scored significantly higher than graduating physician assistant students on the NBME MSK. This may be related to multiple factors, and further studies are necessary to evaluate the overall musculoskeletal clinical competence of both groups of students.

Wound complications in thyroxine-supplemented patients following foot and ankle surgery.

BACKGROUND: Our hypothesis was that thyroxine supplementation in patients undergoing foot and ankle surgery would be associated with increased postoperative wound complications and wound dehiscence compared to patients without thyroxine supplementation. MATERIALS AND METHODS: A retrospective review of 48 patients supplemented with thyroxine that underwent foot and ankle surgery was conducted and analyzed for wound complications. All patients were non-diabetic. A total of 94 historical controls were used to compare the incidence of wound complications to the thyroxine sample. Patient demographics, medical comorbidities, principal diagnosis and procedure performed were recorded. The presence or absence of wound dehiscence, infection or other wound complications was recorded for all patients based on the followup clinical notes in the electronic record. RESULTS: In the thyroxine group, the most common diagnosis was degenerative arthritis (31%, n=15), which also occurred in 28.7% of control patients (n=27). Wound dehiscence was reported in 36.2% (n=17) of thyroxine-supplemented patients compared to 10.8% of control patients (n=10). After adjusting for age, gender, hypertension diagnosis, and vascular disease diagnosis, the odds for wound dehiscence remained significantly greater for the thyroxine group compared to control patients (adjusted OR=3.7; 95% CI: (1.3, 11.4); p=0.01). CONCLUSION: Overall, our results suggest increased wound dehiscence complications in the postoperative period for thyroxine-supplemented patients compared to control patients. This finding remained even after adjusting for the associated cardiovascular comorbidities seen in thyroxine-supplemented patients.

Olfactory deficit detected by fMRI in early Alzheimer's disease.

Alzheimer's disease (AD) is accompanied by smell dysfunction, as measured by psychophysical tests. Currently, it is unknown whether AD-related alterations in central olfactory system neural activity, as measured by functional magnetic resonance imaging (fMRI), are detectable beyond those observed in healthy elderly. Moreover, it is not known whether such changes are correlated with indices of odor perception and dementia. To investigate these issues, 12 early stage AD patients and 13 nondemented controls underwent fMRI while being exposed to each of three concentrations of lavender oil odorant. All participants were administered the University of Pennsylvania Smell Identification Test (UPSIT), the Mini-Mental State Examination (MMSE), the Mattis Dementia Rating Scale-2 (DRS-2), and the Clinical Dementia Rating Scale (CDR). The blood oxygen level-dependent (BOLD) signal at primary olfactory cortex (POC) was weaker in AD than in HC subjects. At the lowest odorant concentration, the BOLD signals within POC, hippocampus, and insula were significantly correlated with UPSIT, MMSE, DRS-2, and CDR scores. The BOLD signal intensity and activation volume within the POC increased significantly as a function of odorant concentration in the AD group, but not in the control group. These findings demonstrate that olfactory fMRI is sensitive to the AD-related olfactory and cognitive functional decline.