Contribution of components of the quadriceps femoris muscle for producing external torque in patients with patellofemoral pain syndrome

IntroductionDifferent muscular activities of the quadriceps components for producing necessary torque may change in patients with patellofemoral pain syndrome (PFPS). The aim of the current study, therefore, was to assess the contribution of each component of the quadriceps femoris muscle for producing external torque in patients with PFPS.MethodTwelve females with PFPS (24.7 ± 2.3 years) and twelve healthy matched females (25.4 ± 2.4 years) performed three consecutive knee flexion and extension movements with maximum effort at 45°/s and 300°/s using a Biodex system 3 dynamometer. Simultaneously, electromyographic (EMG) activities of the vastus medialis oblique (VMO), RF (rectus femoris) and vastus lateralis (VL) muscles were recorded using a DataLog instrument. Standard multiple regressions were used to assess the ability of EMG activities of the VMO, RF and VL muscles to predict normalized quadriceps femoris isokinetic concentric and eccentric torques at 45°/s and 300°/s in the normal and patient groups.ResultsIn the normal group, the VL and the VMO were the good predictors of quadriceps concentric torque at 45°/s and 300°/s, respectively. The VL and the RF were the good predictors of quadriceps eccentric torque at 300°/s in the patient group. No other conditions showed a considerable prediction for quadriceps torque in the normal or patient group.ConclusionFemales with PFPS differ with normal females in terms of the contribution of each component of the quadriceps femoris for producing external torque. Training the VMO for concentric contraction at both high and low velocities should be included in the management of the patients with PFPS.     

The effects of textured materials on static balance in healthy young and older adults: A systematic review with meta-analysis

BackgroundStanding on textured materials can improve static balance, potentially by modulating somatosensory inputs from the soles of the feet.Research questionTo synthesise and quantify the immediate effects of textured materials on static balance in healthy young and older adults.MethodsPrimary outcomes were the centre of pressure (COP) displacement and velocity, during eyes open and eyes closed conditions. Ten crossover studies (n = 318, 58% female) met the inclusion criteria. A random effects meta-analysis model derived pooled standardised mean differences (SMD; Hedges g) to quantify the effects of textured materials. Heterogeneity was quantified with the tau-statistic (τ). A 95% prediction interval quantified the likely range of true effects on COP outcomes in similar future studies.ResultsThere was a small to moderate beneficial effect for textured materials vs control conditions in: COP displacement during both eyes open (SMD: 0.29; 95% CI -0.06 to 0.64; τ = 0.32) and eyes closed (SMD: 0.75; 95% CI 0.18 to 1.33; τ = 0.55). A trivial to small beneficial effect was observed in COP velocity during eyes open (SMD: 0.14; 95% CI -0.14 to 0.43; τ = 0.18) and eyes closed (SMD: 0.20; 95% CI 0.01 to 0.40; τ = 0.18) for textured materials. The 95% prediction intervals showed texture may not consistently provide beneficial results across studies for all outcomes: COP displacement EC (-0.61 to 2.12), EO (-0.54 to 1.12), COP velocity EC (-0.27 to 0.68) and EO (-0.44 to 0.73).SignificanceOverall, textured materials improved balance, but these effects were heterogeneous. This research may therefore inform applied investigations into balance improvements for healthy populations, for example, in functional movements and sports.     

MHPG and heart rate as correlates of nonresponse to drug therapy in panic disorder patients

Little is known about biological predictors of treatment response in panic disorder (PD). In the present study heart rate, blood pressure, plasma cortisol and plasma MHPG were investigated at baseline in a sample of 44 PD patients as possible predictors for nonresponse to treatment. We used a strict definition of nonresponse to find patients who did not respond at all after 12 weeks of treatment with brofaromine or fluvoxamine. Patients were considered nonresponders when they fulfilled two criteria: they did not show a 50% reduction of agoraphobic avoidance and they still experienced panic attacks at endpoint. The variables that differed significantly between the groups were used to predict nonresponse to drug therapy. Using this strict definition of nonresponse, 15 patients (32.6%) were considered nonresponders. These patients were characterised by a higher plasma MHPG concentration and a higher heart rate at baseline. These variables were subsequently used to predict nonresponse.     

Prevalent vertebral deformities predict increased mortality and increased fracture rate in both men and women: A 10-year population-based study of 598 individuals from the Swedish cohort in the European Vertebral Osteoporosis Study

The aim of this study was to evaluate whether a prevalent vertebral deformity predicts mortality and fractures in both men and women. In the city of Malmö, 598 individuals (298 men, 300 women; age 50–80 years) were selected from the city's population and were included in the Swedish part of the European Vertebral Osteoporosis Study (EVOS). At baseline the participants answered a questionnaire and lateral spine radiographs were performed. The prevalence of subjects with vertebral deformity was assessed using a morphometric method. The mortality during a 10-year follow-up period was determined through the register of the National Swedish Board of Health and Welfare. Eighty-five men and 43 women died during the study period. The subsequent fracture incidence during the follow-up period was ascertained by postal questionnaires, telephone interviews and by a survey of the archives of the Department of Radiology in the city hospital. Thirty-seven men and 69 women sustained a fracture during the study period. Data are presented as hazard ratios (HR) with 95% confidence interval (95% CI) within brackets. Prevalent vertebral deformity, defined as a reduction by more than 3 standard deviations (SD) in vertebral height ratio, predicted mortality during the forthcoming decade in both men [age-adjusted HR 2.4 (95% CI 1.6–3.9)] and women [age-adjusted HR 2.3 (95% CI 1.3–4.3)]. In men there was an increased mortality due to cardiovascular and pulmonary diseases and in women due to cancer. Prevalent vertebral deformity predicted an increased risk of any fracture during the forthcoming decade in both men [age-adjusted HR 2.7 (95% CI 1.4–5.3)] and women [age-adjusted HR 1.8 (95% CI 1.1–2.9)]. Prevalent vertebral deformity predicted an increased risk of any subsequent fragility fracture in women [age-adjusted HR 2.0 (95% CI 1.1–3.5)]; however, in men the increased risk was nonsignificant [age-adjusted HR 1.9 (95% CI 0.7–5.1)]. In summary, a prevalent vertebral deformity can predict both increased mortality and increased fracture incidence during the following decade in both men and women. We conclude that prevalent vertebral deformity could be used as a risk factor in both genders for mortality and future fracture.     

胎儿股骨长度测量判断胎儿成熟度的探讨

本文通过对131例妊娠中晚期胎儿的股骨长度(FL)、胎盘分级(PG),胎头双顶径(BPD)羊水(AF)等超声显象观测,探讨了FL对预测胎儿成熟度的价值,并分析了四者之间的相互关系,发现不同胎龄儿FL不同,FL随胎龄增加而增长,并与PG、BPD呈正相关关系,作者认为FL是判断胎儿成熟的有效指标。     

Colonoscopy — how difficult,how painful?

Colonoscopy is sometimes painful for the patient and often difficult for the endoscopist, but it is hard to predict how difficult or painful the examination will be. The purpose of this study was to identify factors that influence difficulty and pain during colonoscopy.Some 1,284 consecutive patients undergoing office colonoscopy by three endoscopists were prospectively studied. A standard questionnaire was completed by the nursing staff, who assessed the degree of difficulty and pain associated with each exam on a four-point scale.There were 682 men and 551 women (sex not recorded in 51). There was no pain in 27%, mild pain in 39%, moderate pain in 25%, and severe pain in 9%. There was no difficulty in 25%, mild difficulty in 33%, moderate difficulty in 28%, and severe difficulty in 14%. Colonoscopy was significantly easier (P<0.001, chi square) and less painful (P<0.001, chi square) in patients after sigmoidectomy. It was more painful after hysterectomy (P<0.05, chi square) and more difficult and painful in women than in men (P<0.01, chi square). There were significant differences between endoscopists in the assessment of pain associated with colonoscopy.Most colonoscopies are associated with little or no pain (66%) and are easy or only mildly difficult to perform (58%). Patients who have had sigmoid resection are especially easy and painless to examine while women, especially after hysterectomy, are at higher risk of having a painful experience. Colonoscopy technique can influence the amount of pain experienced by the patient.     

Human smooth pursuit during transient perturbations of predictable and unpredictable target movement

Summary The predictive component of human smooth pursuit was studied by perturbing sinusoidal target motion at unpredictable instants. The disturbances consisted of either a brief period of stabilization of the target on the fovea or a replacement of the sine by a ramp displacement for half a period. To minimize the effects of a possible change of the tracking strategy by the subject the transitions were masked and only the initial part of the response to the disturbance was analyzed. After stabilization on the fovea the eye oscillation continued at the frequency of the preceding target movement for about one half-cycle, whereupon the oscillation was rapidly damped. The mean unidirectional smooth eye acceleration was 70% of the mean unidirectional target acceleration prior to the stabilization. This suggests that during pursuit of a sinusoidal target movement about 75% of the oculomotor response is generated by predictive processes. When the sine was replaced by a ramp, starting at the velocity zero-crossing, the eye accelerated away from the target for ca. 180 ms irrespective of the frequency of prior tracking. In contrast, when the ramp started at the peak velocity of the sinusoidal target motion the eye accelerated away from the target for more than a quarter period. After foveal stabilization during pursuit of a pseudorandom stimulus, the eye continued to oscillate for less than one period at approximately the highest frequency present in the stimulus. The frequency characteristics of human smooth pursuit of predictable as well as unpredictable target motion were correctly simulated by a model, which derived its predictive properties from a lead element, tuned to the current frequency of the target motion.