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1.
《Gait & posture》2022
BackgroundIncreased hip adduction and internal rotation can lead to excessive patellofemoral joint stress and contribute to patellofemoral pain development. The gluteus maximus acts as a hip extensor, abductor, and external rotator. Improving hip extensor use by increasing one’s forward trunk lean in the sagittal plane may improve frontal and transverse plane hip kinematics during stair ascent.Research questionDoes increasing forward trunk lean during stair ascent affect peak hip adduction and internal rotation?MethodsTwenty asymptomatic females performed five stair ascent trials (96 steps/min) on an instrumented stair using their self-selected and forward trunk lean postures. Three-dimensional kinematics (200 Hz) and kinetics (2000 Hz) were recorded during the stance phase of stair ascent. Biomechanical dependent variables were calculated during the stance phase of stair ascent and included peak forward trunk lean, hip flexion, hip adduction, hip internal rotation angles, and the average hip extensor moment.ResultsDuring the forward trunk lean condition, decreases were observed for peak hip adduction (MD = 2.8˚; 95% CI = 1.9, 3.8; p < 0.001) and peak hip internal rotation (MD = 1.1˚; 95% CI = 0.1, 2.2; p = 0.04). In contrast, increases were observed during the forward trunk lean condition for the peak forward trunk lean angle (MD = −34.7˚; 95% CI = −39.1, −30.3; p < 0.001), average hip extensor moment (MD = −0.5 N·m/kg; 95% CI = −0.5, −0.4; p < 0.001), and stance time duration (MD = −0.02 s; 95% CI = −0.04, 0.00; p = 0.017).SignificanceIncreasing forward trunk lean and hip extensor use during stair ascent decreased peak hip adduction and internal rotation in asymptomatic females. Future studies should examine the effects of increasing forward trunk lean on hip kinematics, self-reported pain, and function in individuals with patellofemoral pain. 相似文献
2.
《Research in microbiology》2022,173(3):103901
Infections caused by Klebsiella pneumoniae are often difficult to manage due to the high frequency of multidrug resistance, often conferred by efflux pumps. In this study, we analyzed sequence variations of the major RND family multidrug efflux pump AcrB from 387 assembled K. pneumoniae genomes. We confirm that AcrB is a highly-conserved efflux pump in K. pneumoniae, and identified several variants that were prevalent in clinical isolates. Molecular dynamics analyses on two of these variants (L118M and S966A) suggested conformational changes that may correlate with increased drug efflux capabilities. The L118M change resulted in enhanced protein rigidity while the flexibility of drug binding pockets was stable or increased, and the interactions between the proximal pockets and water molecules were stronger. For S966A, the significantly enlarged proximal pocket suggested higher drug accommodation ability. Consistent with these predictions, the L118M and S966A variants conferred a slightly increased ability to grow in the presence of tetracycline and to survive cefoxitin exposure when overexpressed. In summary, our results suggest that the emergence of enhanced-function AcrB variants may be a potential risk for increased antibiotic resistance in clinical K. pneumoniae isolates. 相似文献
3.
BackgroundPost-operative elderly hip fracture patients require significant rehabilitation. Nandrolone is an anabolic steroid used to promote muscle growth. This study aims to examine the effect of nandrolone in improving rehabilitation and quality of life in elderly female patients with hip fractures undergoing hemiarthroplasty.MethodsThis is a double-blinded prospective randomized-controlled-trial consisting of female patients above the age of 65 with an isolated neck of femur fracture planned for a hip hemiarthroplasty. Participants were randomized into two arms of the study – 50 mg intramuscular nandrolone vs normal saline placebo administered on post-operative day 0, and weeks 2, 6 and 12. The participants were followed up across a 1-year period following the surgery. Clinical outcomes such as time taken to achieve rehabilitation milestones, distance of ambulation and thigh muscle girth, and functional scoring with SF-36 questionnaire were recorded at intervals of 2, 6 and 12 weeks, 6 months and 1 year following the surgery.ResultsThere were a total of 23 subjects with 11 in the steroid group and 12 in the placebo group. There was no significant difference in demographics and injury patterns between both groups. There was no significant difference for time taken to achieve various rehabilitation milestones and distance of ambulation. SF-36 scores on discharge and at 1-year follow-up mark were comparable. There was no difference in the complication rate between both groups.ConclusionIntra-muscular Nandrolone after hip surgery in elderly female patients does not result in short to mid-term improved rehabilitation or functional outcomes. Nandrolone did not result in increased short-term complications after hip surgery.Level of evidenceI. 相似文献
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《Injury》2023,54(7):110761
ObjectivesHistorically, pelvic ring fractures (PRF) are considered to occur predominantly in the anterior ring and therfore to be mechanically stable. Combined anterior and posterior (A + P) PRF are expected to be less mechanically stable and therefore to be associated with higher levels of pain and reduced mobility compared to isolated anterior fractures. The current study investigates the clinical relevance of combined A + P PRF in elderly patients.MethodsA prospective multicentre cohort study was conducted in patients >70 years of age with anterior PRF after low-energy trauma diagnosed on conventional radiographs. All patients underwent an additional CT-scan. Patients were divided into two groups; isolated anterior or combined A + P fractures. Patients were treated conservatively with adequate analgesia for at least one week. If patients could not be mobilised after conservative treatment, surgical fixation was performed. Numerical Rating Scale (NRS) pain scores, dependence on walking aids and Activities of Daily Living scores (ADL) were measured at 2–4 weeks, and 3, 6 and 12 months after fracture.Results102 patients (age 81.1 ± 7.6 years) were included. Isolated anterior fractures were diagnosed in 25 (24.5%) and A + P fractures in 77 (75.5%) patients. Baseline characteristics did not differ between the two groups. Most patients were successfully treated conservatively and 5 (4.9%) underwent percutaneous trans-iliac, trans-sacral screw fixation after failure of conservative treatment. At 2–4 weeks post trauma, patients with A + P fractures had similar median pain scores (3 (range 0–8) vs. 5 (0–10), p = 0.19) and ADL scores (85 (25–100) vs. 78.6 (5–100), p = 0.67), but were more dependent on walking aids (92.8% vs. 72.2%; p = 0.02) compared to patients with isolated anterior fractures. There were no significant differences at 3 months. At one year follow-up the median NRS pain and ADL scores for both fracture groups were 0 and 100, respectively. Mortality was 10.8%, and additional loss to follow-up was 17.6%.ConclusionsThe vast majority of elderly patients with PRF have combined A + P fractures. The clinical implications of additional posterior pelvic ring fractures in elderly patients appears to be limited. 相似文献
7.
Qiangsheng He Chongfei Huang Xiwen Qin Yuanyuan Yu Di Tang Junjie Huang Zi Chong Kuo Yuyao Ling Deli Mao Bin Xia Wenjing Li Kuiqing Lu Man Yang Yulong He Wenbo Meng Jinqiu Yuan Yihang Pan 《International journal of cancer. Journal international du cancer》2023,153(5):942-949
Recent epidemiological studies suggested that proton pump inhibitor (PPI) use was associated with an increased risk of biliary tract cancer (BTC), however, confounders were not adequately controlled. Our study aimed to evaluate PPI use and subsequent risk of BTC and its subtypes in three well-established cohorts. We conducted a pooled analysis of the subjects free of cancers in UK Biobank (n = 463 643), Nurses' Health Study (NHS, n = 80 235) and NHS II (n = 95 869). Propensity score weighted Cox models were used to estimate marginal HRs of PPIs use on BTC risk, accounting for potential confounders. We documented 284 BTC cases in UK Biobank (median follow-up: 7.6 years), and 91 cases in NHS and NHS II cohorts (median follow-up: 15.8 years). In UK biobank, PPI users had a 96% higher risk of BTC compared to nonusers in crude model (HR 1.96, 95% CI 1.44-2.66), but the effect was attenuated to null after adjusting for potential confounders (HR 0.95, 95% CI 0.60-1.49). PPI use was not associated with risk of BTC in the pooled analysis of three cohorts (HR 0.93, 95% CI 0.60-1.43). We also observed no associations between PPI use with risk of intrahepatic (HR 1.00, 95% CI 0.49-2.04), extrahepatic bile duct (HR 1.09, 95% CI 0.52-2.27) and gallbladder cancers (HR 0.66, 95% CI 0.26-1.66) in UK Biobank. In summary, regular use of PPIs was not associated with the risk of BTC and its subtypes. 相似文献
8.
Yi Su Jean W. Woo Timothy C.Y. Kwok 《Journal of the American Medical Directors Association》2019,20(1):83-89
Objectives
To examine the potential added value of a simple 5-item questionnaire for sarcopenia screening (SARC-F) to the Fracture Risk Assessment Tool (FRAX) for hip fracture risk prediction, in order to identify at-risk older adults for screening with dual-energy x-ray absorptiometry (DXA).Design
A prospective cohort study.Setting and participants
Two thousand Chinese men and 2000 Chinese women aged 65 years or older were recruited from local communities and were prospectively followed up for about 10 years.Measures
Areal bone mineral density (BMD) of hip and lumbar spine were measured by DXA at baseline. Ten-year FRAX probability of hip fracture was calculated using the baseline risk factors. Information from the baseline questionnaire was extracted to calculate a modified SARC-F score. The independent predictive values of SARC-F and FRAX questionnaire were evaluated using multivariate survival analysis. The added predictive values of SARC-F to FRAX for pre-DXA screening were examined.Results
During the follow-up, 63 (3.2%) men and 69 (3.5%) women had at least 1 incident hip fracture. SARC-F had an independent value of FRAX for hip fracture risk prediction, with an adjusted hazard ratio [95% confidence interval (CI)] of 1.24 (1.02, 1.52) and 1.15 (0.99, 1.13) in men and women, respectively. Compared with using FRAX, using SARC-F in conjunction with FRAX made the sensitivity for prediction rise from 58.7% to 76.2% in men and from 69.6% to 78.3% in women, with a nondecreased area under receiver operating characteristic curve of 0.67. Prescreening using FRAX in conjunction with SARC-F could save more than half of the DXA assessment than with no prescreening.Conclusions/Implications
SARC-F is associated with a modest increase in hip fracture risk, especially in men. Conjoint evaluation for sarcopenia in addition to FRAX screening may help identify older adults at higher risk of hip fracture for more intensive screening and/or preventive interventions. 相似文献9.
Bartosz Slomka Witold Rongies Janusz Sierdzinski Wlodzimierz Dolecki Marta Worwag Ewa Trzepla 《Acta orthopaedica et traumatologica turcica》2019,53(1)
Objective
The aim of the study was to assessment the impact of hip osteoarthritis on postural stability.Methods
One hundred and twenty-five randomly selected women 20–85 years old (mean age of 49 ± 24.4 years) were assigned to three groups based on age, health status and activity level. Group 1 (cases) – elderly women with diagnosed hip osteoarthritis, group 2 (control) - women without hip osteoarthritis, and group 3 (control) - healthy young women. Assessment of postural stability were measured using a WIN-POD Pel 38 electronic podometer. Statistica 10 software was used to perform t-test resulting in significance level of p < 0.05.Results
Significant differences in pedobarographic balance measurements were observed between the study groups with eyes opened or closed (deviation length eyes open: group 1–3 and 2–3 p < 0.0001; eyes closed group 1–2 p = 0.19; 1–3 and 2–3 p < 0.0001; deviation area eyes open: group 1-3 and 2–3 p < 0.0001; eyes closed group 1–3 and 2–3 p < 0.0001; deviation velocity eyes open: group1-3 and 2–3 p < 0.0001; eyes closed group 1–2 p < 0.010, 1–3 and 2–3 p < 0.0001). The poorest postural stability was observed in patients with hip osteoarthritis (deviation length eyes open vs eyes closed 180.8/201.7 p = 0.028, deviation area 128.7/145.7 p = 0.771, deviation velocity 5.1/6.1 p < 0.0001), and the best postural stability was observed in young women (deviation length 111.3/137.5 p < 0.0001, deviation area 57/76.9 p = 0.003, deviation velocity 3.4/4.2 p < 0.0001).Conclusion
(1) Osteoarthritic degeneration of the hip joint results in a significant disturbance in proprioception. This finding was reflected by the inferior stability parameters collected from subjects with hip osteoarthritis when asked to stand with their eyes closed. These finding were not observed in the other groups. (2) The disorder of the body stability of people with osteoarthritis may be a relative indication for the implantation of hip arthroplasty. 相似文献10.
《Gait & posture》2019
BackgroundFollowing rehabilitation for total knee arthroplasty, “quadriceps avoidance gait”, defined by limited knee flexion angle excursion during walking, persists and contributes to poor long-term outcomes. Given the presence of several post-surgical impairments, identifying the contribution of multiple factors to knee flexion angle excursion is important to developing targeted interventions to improve recovery after total knee arthroplasty.Research questionsWhich outcomes continue to improve following rehabilitation for total knee arthroplasty? What are the primary contributors to impaired knee flexion angle excursion during walking following total knee arthroplasty?MethodsPeak muscle strength and rate of torque development of the quadriceps, hip abductors, and hip external rotators, five-time sit-to-stand test, Knee Injury & Osteoarthritis Outcome Score, and gait mechanics were assessed in 24 participants at three and six months post-surgery. Paired sample t-tests or Wilcoxon Signed-Rank tests were used to compare outcomes between assessments. Stepwise multiple linear regression were used to assess the contribution of each measure to knee flexion angle excursion.ResultsSignificant improvements were noted in all outcomes except hip external rotation rate of torque development, gait speed, and knee flexion angle excursion. Quadriceps rate of torque development and knee pain significantly contributed to knee flexion angle excursion at three months (Adjusted R2 = 0.342), while quadriceps rate of torque development and peak hip external rotation strength significantly contributed at six months (Adjusted R2 = 0.436).SignificanceWhile higher pain levels at three months and greater peak hip external rotation muscle strength at six months contribute to impaired knee flexion angle excursion, quadriceps rate of torque development was the primary contributor to knee flexion angle excursion at both three and six months after surgery. Implementing strategies to maximize quadriceps rate of torque development during rehabilitation may help to reduce quadriceps avoidance gait after total knee arthroplasty. 相似文献