Two-ring hybrid external fixation of distal tibial fractures: a review of 47 cases

BACKGROUND: The healing of a metaphyseal fracture line is a major problem in cases of distal tibial fracture treated with external fixation. METHODS: Forty-seven distal tibial fractures treated with two-ring Ilizarov hybrid external fixation (16 AO/OTA type A and 31 type C, 10 open) were followed up. Fracture reduction and union time was evaluated and IOWA and RAND 36-Item Health Survey scores were used to assess functional outcome. RESULTS: Thirty-five fractures united uneventfully in a median time of 20 weeks, but 12 fractures needed additional procedures because of delayed union. According to univariate analysis, the risk factors for a longer time needed for fracture union were translational displacement and current smoking, and the risk factors for reoperation because of delayed union translational displacement fibular fracture fixation, and the number of cigarettes smoked per day. In multivariate analysis, translational displacement was a risk factor for both longer time to fracture union and reoperation and fibular fracture fixation was a risk factor for reoperation. If the translational displacement was less than 3 mm, the reoperation rate was 6%, whereas if the displacement was more than 3 mm, it was 83%. Reoperation was performed on 50% of the patients who underwent fibular fixation and on 15% of the patients who did not undergo fibular fixation. There were only marginal decreases in the range of motion and arthritis scores in the AO/OTA fracture types other than type C3. There were no significant differences in RAND 36 scores between the general Finnish population aged 18 to 64 years and our patients. CONCLUSIONS: Hybrid external fixation of distal tibial fractures is associated with delayed union, which is closely related to the degree of residual translational displacement after reduction. Fixation of an associated fibular fracture does not help to achieve better contact in the tibial fracture and increases the risk of delayed union.     

A new quantitative measure of disc degeneration

Background Context

The ability to adequately measure a phenomenon is critical to studying and understanding it. Since 1957, a variety of subjective visual grading methods have been used to assess disc degeneration, but these have been limited by gross ordinal scales and imprecision, as well as suboptimal reliability. Conceptually sound, objective, precise measurements are needed to advance knowledge of disc degeneration and its causes, progression, and consequences.

Amyloid and metabolic positron emission tomography imaging of cognitively normal adults with Alzheimer's parents

This study examines the relationship between fibrillar beta-amyloid (Aβ) deposition and reduced glucose metabolism, a proxy for neuronal dysfunction, in cognitively normal (NL) individuals with a parent affected by late-onset Alzheimer's disease (AD). Forty-seven 40–80-year-old NL received positron emission tomography (PET) with ¹¹C-Pittsburgh compound B (PiB) and 18F-fluoro-2-deoxy-d-glucose (FDG). These included 19 NL with a maternal history (MH), 12 NL with a paternal history (PH), and 16 NL with negative family history of AD (NH). Automated regions of interest, statistical parametric mapping, voxel-wise intermodality correlations, and logistic regressions were used to examine cerebral-to-cerebellar PiB and FDG standardized uptake value ratios across groups. The MH group showed higher PiB retention and lower metabolism in AD regions compared with NH and PH, which were negatively correlated in posterior cingulate, frontal, and parieto-temporal regions (Pearson r ≤ −0.57, p ≤ 0.05). No correlations were observed in NH and PH. The combination of Aβ deposition and metabolism yielded accuracy ≥ 69% for MH vs. NH and ≥ 71% for MH vs. PH, with relative risk = 1.9–5.1 (p values < 0.005). NL individuals with AD-affected mothers show co-occurring Aβ increases and hypometabolism in AD-vulnerable regions, suggesting an increased risk for AD.     

Lack of CD44 variant 6 expression in rectal cancer invasive front associates with early recurrence

AIM: To investigate the prognostic value of CD44 variant 6 (CD44v6), a membranous adhesion molecule, in rectal cancer.METHODS: Altogether, 210 rectal cancer samples from 214 patients treated with short-course radiotherapy (RT, n = 90), long-course (chemo) RT (n = 53) or surgery alone (n = 71) were studied with immunohistochemistry for CD44v6. The extent and intensity of membranous and cytoplasmic CD44v6 staining, and the intratumoral membranous staining pattern, were analyzed.RESULTS: Membranous CD44v6 expression was seen in 84% and cytoplasmic expression in 81% of the cases. In 59% of the tumors with membranous CD44v6 expression, the staining pattern in the invasive front was determined as “front-positive” and in 41% as “front-negative”. The latter pattern was associated with narrower circumferential margin (P = 0.01), infiltrative growth pattern (P < 0.001), and shorter disease-free survival in univariate survival analysis (P = 0.022) when compared to the “front-positive” tumors.CONCLUSION: The lack of membranous CD44v6 in the rectal cancer invasive front could be used as a method to identify patients at increased risk for recurrent disease.     

Ruling Out Myocardial Infarction with Troponin T and Creatine Kinase MB Mass: Diagnostic and Prognostic Aspects

Objective - To investigate the time window for ruling out myocardial infarction (MI) with troponin T (TnT) and creatine kinase isoenzyme MB mass (CK-MBm) and the prognosis of patients with ruled-out MI diagnosis. Design - The study was based on 397 patients admitted with a suspected acute coronary syndrome but with relief of symptoms within 24 h. Results - MI diagnosis was confirmed with elevated TnT (> 0.10 µg/l) in 108 patients, in 91% within 12-24 h from the onset of symptoms, and in 99% within 12 h from admission. In 94 of these patients CK-MBm became elevated (> 5.0 µg/l), in 95% within 10-12 h from the onset of symptoms, and in 99% within 6 h from admission. Among patients with ruled-out MI diagnosis, the 1-year incidence of recurrent coronary events was 29% in those with positive history of coronary heart disease (CHD) but only 7% in those without prior CHD ( p < 0.001). Conclusion - Using TnT or CK-MBm, MI can be ruled out within 12 h from admission in the majority of patients. Among patients with ruled-out MI diagnosis, positive history of CHD is an important determinant of prognosis.     

Brown adipose tissue function is accompanied by cerebral activation in lean but not in obese humans

Brown adipose tissue (BAT) is able to generate heat and dissipate energy in response to cold exposure in mammals. It has recently been acknowledged that adult humans also have functional BAT, whose metabolic activity is reduced in obesity. In healthy humans, the cerebral mechanisms that putatively control BAT function are unclear. By using positron emission tomography (PET), we showed that cold-induced BAT activation is associated with glucose metabolism in the cerebellum, thalamus, and cingulate, temporoparietal, lateral frontal, and occipital cortices in lean participants, whereas no such associations were found under warm control conditions. The cold-induced increase in cerebral glucose metabolism was more robust in lean than obese participants. Cerebral glucose metabolism was not associated with skeletal muscle or white adipose tissue glucose uptake under warm or cold conditions. In conclusion, BAT metabolism was accompanied by the activation of specific cerebral regions, and this shows an uncharacterized role that the brain plays in the regulation of BAT function. In obese participants, the cold-induced response in cerebral activity was attenuated that provides a clue for obesity-induced impairment in BAT metabolism.