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Objective
Symptomatic distal interlocking screws in retrograde femoral nailing are common due the difficulties of imaging the trapezoidal femur. Screws appearing to have appropriate length on imaging may possibly be prominent, creating symptoms. Screw trajectory may influence the degree of this radiographic error. We hypothesize that external rotation of screw trajectory will increase measurement error of screw length.Design
Retrospective.Setting
Urban Level I Tertiary Trauma Center.Participants
283 patients with Computer Tomography (CT) scans of the native knee were retrospectively identified. Simulation was done of the trajectory of an interlock at 20?mm and 40?mm proximal to the nail entry point, which represent common screw positions associated/not associated respectively, with removal. The distance between the radiographic medial cortex and the tip of the transverse screw was calculated (D). The angle (Ψ) between the transverse trajectory and a modified trajectory aimed at the most medial cortex to avoid radiographic measurement error was calculated. Geometric modeling was utilized to calculate the measurement error (D) in the event of accidental external rotation. The angle of the medial slope was also measured (Θ).Intervention
Review of CT imaging of normal distal femora.Main Outcome Measurements
CT measurements of distal femora.Results
The mean distance (D) at 20/40?mm was 4.21 [95%CI 4.02–4.402] and 2.03?mm [95%CI 1.78–2.83], respectively (p?<?0.0001). The mean angle (Ψ) between the transverse and modified trajectory at 20/40?mm was 12° [95%CI 11.5–12.5] and 9.60° [95%CI 9–10.2], respectively (p?<?0.0001). External rotation by a similar amount nearly triples the measured difference (D). The measured medial slope was significantly increased as screws were placed more proximal (Θ20 mm 46.5 vs Θ40 mm: 48.7?°, p?<?0.00001).Conclusion
The distance between the perceived medial cortex and the tip of the most transverse screw is 4.21?mm and could account for painfully prominent screws. In more proximal screws this distance is decreased. Internal rotation of the screw trajectory 12° can reduce this distance (D), which has implications in nail design. External rotation, amplifies this difference nearly three-fold. Surgeons should avoid external rotation of the aiming arm to prevent prominent screws. 相似文献5.
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Psychiatric Quarterly - The aim of the present study was to increase the understanding of veteran experiences with receiving an evidence-based psychotherapy (EBPs) for PTSD (Cognitive Processing... 相似文献
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Liselotte De Wit Melanie Chandler Priscilla Amofa Brittany DeFeis Andrea Mejia Deirdre O’Shea 《Neuropsychological rehabilitation》2021,31(1):92-104
ABSTRACT This study aimed to identify predictors of learning and adherence to a previously validated compensatory calendar and note-taking system (Memory Support System; MSS) in persons with amnestic mild cognitive impairment (aMCI). Age, education, global cognition, depression, and memory-related self-efficacy were studied as predictors of individuals’ ability to learn the use of the MSS during the two-week training and of their adherence to the MSS 6, 12, and 18 months after training. How well an individual was able to learn the use of the MSS was itself examined as a predictor of adherence. Two-hundred-and-fifteen older adults with aMCI and their study partners (e.g., spouse, adult child) received MSS training one-hour daily for 10 days. Ordinal logistic regression analyses indicated that (1) global cognition predicted MSS learning at end of training, and (2) MSS learning at end of trainng predicted MSS adherence at 6, 12, and 18 months post-training. The current study suggests that offering compensatory strategies as early as possible for those with MCI might be of most benefit, and might have implications for long-term adherence. 相似文献
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EH Gemmill DJ Humes JA Catton 《Annals of the Royal College of Surgeons of England》2015,97(3):173-179
Introduction
Fast track methodology or enhanced recovery schemes have gained increasing popularity in perioperative care. While evidence is strong for colorectal surgery, its importance in gastric and oesophageal surgery has yet to be established. This article reviews the evidence of enhanced recovery schemes on outcome for this type of surgery.Methods
A systematic literature search was conducted up to March 2014. Studies were retrieved and analysed using predetermined criteria.Results
From 34 articles reviewed, 18 eligible studies were identified: 7 on gastric and 11 on oesophageal resection. Three randomised controlled trials, five case-controlled studies and ten case series were identified. The reported protocols included changes to each stage of the patient journey from pre to postoperative care. The specific focus following oesophageal resections was on early mobilisation, a reduction in intensive care unit stay, early drain removal and early (or no) contrast swallow studies. Following gastric resections, the emphasis was on reducing epidural anaesthesia along with re-establishing oral intake in the first three postoperative days and early removal of nasogastric tubes.In the papers reviewed, mortality rates following fast track surgery were 0.8% (9/1,075) for oesophageal resection and 0% (0/329) for gastric resection. The reported morbidity rate was 16.5% (54/329) following gastric resection and 38.6% (396/1,075) following oesophageal resection. Length of stay was reduced in both groups compared with conventional recovery groups in comparative studies.Conclusions
The evidence for enhanced recovery schemes following gastric and oesophageal resection is weak, with only three (low volume) published randomised controlled trials. However, the enhanced recovery approach appears safe and may be associated with a reduction in length of stay. 相似文献10.
Potassium Bicarbonate Supplementation Lowers Bone Turnover and Calcium Excretion in Older Men and Women: A Randomized Dose‐Finding Trial 下载免费PDF全文
Bess Dawson‐Hughes Susan S Harris Nancy J Palermo Cheryl H Gilhooly M Kyla Shea Roger A Fielding Lisa Ceglia 《Journal of bone and mineral research》2015,30(11):2103-2111
The acid load accompanying modern diets may have adverse effects on bone and muscle metabolism. Treatment with alkaline salts of potassium can neutralize the acid load, but the optimal amount of alkali is not established. Our objective was to determine the effectiveness of two doses of potassium bicarbonate (KHCO3) compared with placebo on biochemical markers of bone turnover, and calcium and nitrogen (N) excretion. In this double‐blind, randomized, placebo‐controlled study, 244 men and women age 50 years and older were randomized to placebo or 1 mmol/kg or 1.5 mmol/kg of KHCO3 daily for 3 months; 233 completed the study. The primary outcomes were changes in 24‐hour urinary N‐telopeptide (NTX) and N; changes in these measures were compared across the treatment groups. Exploratory outcomes included 24‐hour urinary calcium excretion, serum amino‐terminal propeptide of type I procollagen (P1NP), and muscle strength and function assessments. The median administered doses in the low‐dose and high‐dose groups were 81 mmol/day and 122 mmol/day, respectively. When compared with placebo, urinary NTX declined significantly in the low‐dose group (p = 0.012, after adjustment for baseline NTX, gender, and change in urine creatinine) and serum P1NP declined significantly in the low‐dose group (p = 0.004, adjusted for baseline P1NP and gender). Urinary calcium declined significantly in both KHCO3 groups versus placebo (p < 0.001, adjusted for baseline urinary calcium, gender, and changes in urine creatinine and calcium intake). There was no significant effect of either dose of KHCO3 on urinary N excretion or on the physical strength and function measures. KHCO3 has favorable effects on bone turnover and calcium excretion and the lower dose appears to be the more effective dose. Long‐term trials to assess the effect of alkali on bone mass and fracture risk are needed. © 2015 American Society for Bone and Mineral Research. 相似文献