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ObjectiveThe aim of this study was to determine whether there is a difference in postural control between nulligravida women and women who have given birth by vaginal or cesarean section.MethodsWomen who had only vaginal delivery in the previous 1–3 years were included in the vaginal delivery group (n = 27), those who had only cesarean delivery in the previous 1–3 years were included in the cesarean section group (n = 28), and those who had never given birth were included in the control group (n = 32). Evaluations were administered 6–8 days after the ovulation phase. Postural control of the participants was evaluated with the computerized dynamic posturography device.ResultsA total of 87 women with a mean age of 29.4 ± 4 years and a mean body mass index of 24.1 ± 3.1 kg/m2 were included in the study. Antero-posterior somatosensory organization test values of the vaginal delivery group were lower than the control group (p = 0.0016). The cesarean delivery group had statistically lower antero-posterior somatosensory (p < 0.001 and p = 0.0013) and medio-lateral somatosensory (p = 0.002 and p = 0.017, respectively) test scores compared to the control group and the vaginal delivery group.ConclusionsIt was observed that women who birthed with vaginal or cesarean delivery had impaired somatosensory postural control. There is definitely a need for further studies with a long-term follow-up examining the effects of postural control during pregnancy and the postpartum period.  相似文献   
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BackgroundVisually induced dizziness can develop as a sequala of a vestibular disorder and is characterized by symptoms of nausea, dizziness, and imbalance in rich visual environments such as supermarkets and shopping malls. To date the mechanisms underlying visually induced dizziness are poorly understood.Research questionWhat are the characteristics of visual fixations and postural sway in adults with visually induced dizziness compared to healthy adults when exposed to increasingly complex visual environments?MethodsWe recruited 20 adults with visually induced dizziness and 20 healthy adults to this cross-sectional exploratory study. Participants were instructed to maintain gaze on letters projected on a large screen with backgrounds of differing visual complexity. The number of visual refixations, movement of the centre of pressure, and movement of the head and body centres of mass were recorded.ResultsAdults with visually induced dizziness showed a significantly higher number of visual refixations (F= 10.592, p < 0.01), and increased mean velocity of head and body centres of mass movement (F= 14.034, p < 0.01 and F= 6.553, p < 0.05 respectively) compared to healthy adults.SignificanceAdults with visually induced dizziness exhibited visual fixational instability and increased postural and head sway compared to healthy adults. This was mainly observed in conditions with complex and moving backgrounds. This may account for reports from adults with visually induced dizziness of worsening symptoms in busy environments. The results from the study may assist in guiding intervention development to reduce symptoms of visually induced dizziness.  相似文献   
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《Seminars in Arthroplasty》2022,32(4):681-687
BackgroundThe objective of this study was to compare complication rates between patients undergoing reverse shoulder arthroplasty (RSA) after a prior open reduction and internal fixation (ORIF) for proximal humerus fracture (PHF) to those undergoing RSA as a primary treatment for PHFs, glenohumeral osteoarthritis, or rotator cuff tear arthropathy (CTA).MethodsPatients who underwent RSA between 2015 and 2020 were identified in the Mariner database. Patients were separated into 3 mutually exclusive groups: (1) RSA for osteoarthritis, rotator cuff tear, or CTA (Control-RSA); (2) RSA as a primary treatment for PHF (PHF-RSA); and (3) RSA for patients with prior ORIF of PHFs (ORIF-RSA). Ninety-day medical and 2-year postoperative surgical complications were identified. In addition, patients in the PHF-RSA group were subdivided into those undergoing RSA for PHF within 3 months of the fracture (acute) vs. those treated greater than 3 months from diagnosis (delayed). Multivariate regression was performed to control for differences in comorbidities and demographics.ResultsA total of 30,824 patients underwent primary RSA for arthritis or CTA, 5389 patients underwent RSA as a primary treatment for a PHF, and 361 patients underwent RSA after ORIF of a PHF. ORIF before RSA was associated with an increased risk of overall revision (odds ratio [OR] 2.45, P = .002), infection (OR 2.40, P < .001), instability (OR 2.43, P < .001), fracture (OR 3.24, P = .001), minor medical complications (OR 1.59, P = .008), and readmission (OR 2.55, P = .001) compared with the Control-RSA cohort. RSA as a primary treatment for PHF was associated with an increased risk of 2-year revision (OR 1.60, P < .001), infection (OR 1.51, P < .001), instability (OR 2.84, P < .001), and fracture (OR 2.54, P < .001) in addition to major medical complications (OR 2.02, P < .001), minor medical complications (OR 1.92, P < .001), 90-day emergency department visits (OR 1.26, P < .001) and 90-day readmission (OR 2.03, P < .001) compared with the Control-RSA cohort. The ORIF-RSA group had an increased risk of periprosthetic infection (OR 1.94, P = .002) when compared with the PHF-RSA cohort. There were no differences in medical or surgical complications in the RSA-PHF cohort between patients treated in an acute or delayed fashion.ConclusionRSA following ORIF of a PHF is associated with increased complications compared with patients undergoing RSA for nonfracture indications. Prior ORIF of a PHF is also an independent risk factor for postoperative infection after RSA compared with patients who undergo RSA as a primary operation for fracture. The timing of RSA as a primary operation for PHF does not appear to impact the rates of postoperative medical and surgical complications.  相似文献   
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BackgroundThe Star Excursion Balance Test (SEBT) is a clinical test that aims to assess postural control. Its interpretation is related to the understanding of the motor specificities required. Adjustments must be made to the center of pressure (COP) to maintain balance during testing movements. Comprehend the specifics of these adjustments for each direction can allow the development of more suitable exercises for balance training. The aim was to compare the positions of the COP on the different directions of the SEBT and correlate the reachs obtained in the SEBT with the distances from the COP to the borders of the base of support (BOS).MethodsSixteen healthy subjects participated in the study. Measurements were made by performing the SEBT over the force platform. The Kruskal-Wallis test followed by Bonferroni's post hoc test was used to compare directions. The Pearson correlation test was used to check the correlation of parametric variables and Spearman correlation test for the nonparametric ones.ResultsThe position of the COP at the touch differs from the anterior direction to the other directions of the SEBT and the performance in this direction is correlated with the proximity of the COP to the anterior limit of the support base. The performances in the other directions did not correlate with the COP position.ConclusionThe requirements of the compensation mechanisms for postural control are different between the directions of the SEBT.  相似文献   
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Women at increased risk of breast cancer have options to mitigate that risk. Understanding factors that increase risk and utilizing tools for quantitative estimates are important to be able to adequately counsel and target strategies for patients. On the basis of these estimates, patients may be able to engage in risk reduction interventions and increased screening, including chemoprevention or surgical risk reduction. Multiple organizations have published guidelines supporting risk assessment, genetic assessment, increased screening, and prevention measures for these women.  相似文献   
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BackgroundIn the phase III MDS-005 study of patients with lower-risk, non-del(5q) myelodysplastic syndromes, lenalidomide was associated with a higher rate of ≥ 8 weeks red blood cell transfusion independence (RBC-TI) compared with placebo, but also with a higher risk of hematologic adverse events (AEs).Patients and MethodsThis analysis evaluated the ratio of clinical benefit-risk in patients treated with lenalidomide or placebo, and assessed the effect of lenalidomide dose reductions on response. Clinical benefit was a composite endpoint defined as RBC-TI, transfusion reduction ≥ 4 units packed red blood cells, hemoglobin increase ≥ 1.5 g/dL, or cytogenetic response.ResultsThe rate of clinical benefit was higher with lenalidomide than with placebo (31.9% vs. 3.8%). The ratio of response (RBC-TI and clinical benefit) to risk (hematologic AEs) favored lenalidomide over placebo. Patients who underwent ≥ 1 lenalidomide dose reduction had a longer duration of treatment, received a higher cumulative dose, and were more likely to experience clinical benefit versus patients without dose reductions.ConclusionDespite the occurrence of hematologic AEs, the overall benefit-risk profile supported lenalidomide treatment. Appropriate management of hematologic AEs by dose reductions may help patients with myelodysplastic syndromes to remain on treatment and achieve clinical benefit.  相似文献   
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