Simultaneous bilateral femoral neck fractures after electrical shock injury: a case report

Simultaneous bilateral fractures of the femoral necks are rare injuries,especially when there is no underlying pathological condition.We report a 20-year-old man who sustained bilateral femoral neck fr...     

Efficacy and Safety of Tol Terodine in People With Neurogenic Detrusor Overactivity

Abstract

Objective: To compare tolterodine with oxybutynin and placebo in people with neuragenie detrusor overactivity.

Design: Prospective, randomized, double-blind, crossover trial plus open-label comparative stage.

Participants: Ten participants with neuragenie detrusor overactivity due to spinal cord injury or multiple sclerosis who usedintermittent catheterization.

Methods: Bladder capacity on cystometrogram, a 10-day record of catheterization volumes, number of incontinent episodes perday, and perceived dry mouth using a visual analog scale (VAS) were measured for the following: (a) a blinded comparison:tolterodine, 2 mg twice daily, vs placebo, twice daily; and (b) an unblinded comparison: oxybutynin vs tolterodine, each atself-selected doses (SSDs).

Results: Tolterodine, 2 mg twice daily, was superior to placebo in enhancing catheterization volumes (P<0.0005) and reducingincontinence (P<0.001 ), but was comparable with placebo in cystometric bladder capacity. Efficacy of tolterodine SSD wascomparable with oxybutynin SSD with regard to catheterization volumes, degree of incontinence, and cystometric bladder capacity.The side effect profile (dry mouth) was comparable between tolterodine, 2 mg twice daily, and placebo, but differed significantlywhen comparing tolterodine SSD with oxybutynin SSD (P<0.05).

Conclusion: T olterodine, when used at SSDs, is comparable with oxybutynin at SSDs in enhancing bladder volume and improvingcontinence, but with less dry mouth. T olterodine at the recommended dosage of 2 mg twice daily improves incontinence and bladdervolumes compared with placebo, and without significant dry mouth. Larger doses of tolterodine may be needed to achieve best effectin this population, but further studies are required.     

Age‐associated changes in muscle activity during isometric contraction

Introduction: We investigated the effect of age on the complexity of muscle activity and the variance in the force of isometric contraction. Methods: Surface electromyography (sEMG) from biceps brachii muscle and force of contraction were recorded from 96 subjects (20–70 years of age) during isometric contractions. Results: There was a reduction in the complexity of sEMG associated with aging. The relationship of age and complexity was approximated using a bilinear fit, with the average knee point at 45 years. There was an age‐associated increase in the coefficient of variation (CoV) of the force of muscle contraction, and this increase was correlated with the decrease in complexity of sEMG (r² = 0.76). Conclusions: There was an age‐associated increase in CoV and also a reduction in the complexity of sEMG. The correlation between these 2 factors can be explained based on the age‐associated increase in motor unit density. Muscle Nerve 47: 545–549, 2013     

Damage and the repeated bout effect of arm,leg, and trunk muscles induced by eccentric resistance exercises

This study compared nine resistance eccentric exercises targeting arm, leg, and trunk muscles in one session for changes in maximal voluntary isometric contraction strength (MVC), delayed onset muscle soreness (DOMS), plasma creatine kinase (CK) activity, and myoglobin (Mb) concentration after the first and second bouts. Fifteen sedentary men (20‐25 years) performed 5 sets of 10 eccentric contractions with 80% of MVC load for the elbow flexors (EF), elbow extensors (EE), pectoralis, knee extensors (KE), knee flexors (KF), plantar flexors (PF), latissimus, abdominis, and erector spinae (ES) in a randomized order and repeated the same exercises 2 weeks later. MVC decreased at 1 (16%‐57%) to 4 (13%‐49%) days, DOMS developed (peak: 43‐70 mm), and CK activity (peak: 23 238‐207 304 IU/L) and Mb concentration showed large increases after the first bout. The magnitude of decrease in MVC was greater (P < 0.05) for EF, EE, and PEC than others and for KF than KE, PF, and ES. DOMS was greater (P < 0.05) for EF, EE, and ES than others. Changes in all measures were smaller (P < 0.05) after the second than the first bout, and the magnitude of the repeated bout effect was similar among the muscles. Plasma CK activity and Mb concentration did not increase significantly after the second exercise bout. It was concluded that muscle damage was greater for arm than leg muscles, and muscle proteins in the blood increased to a critical level after unaccustomed whole‐body resistance exercises, but the magnitude of damage was largely attenuated for all muscles similarly after the second bout.     

Coronary Microembolization with Normal Epicardial Coronary Arteries and No Visible Infarcts on Nitrobluetetrazolium Chloride-Stained Specimens: Evaluation with Cardiac Magnetic Resonance Imaging in a Swine Model

Objective

To assess magnetic resonance imaging (MRI) features of coronary microembolization in a swine model induced by small-sized microemboli, which may cause microinfarcts invisible to the naked eye.

Materials and Methods

Eleven pigs underwent intracoronary injection of small-sized microspheres (42 µm) and catheter coronary angiography was obtained before and after microembolization. Cardiac MRI and measurement of cardiac troponin T (cTnT) were performed at baseline, 6 hours, and 1 week after microembolization. Postmortem evaluation was performed after completion of the imaging studies.

Results

Coronary angiography pre- and post-microembolization revealed normal epicardial coronary arteries. Systolic wall thickening of the microembolized regions decreased significantly from 42.6 ± 2.0% at baseline to 20.3 ± 2.3% at 6 hours and 31.5 ± 2.1% at 1 week after coronary microembolization (p < 0.001 for both). First-pass perfusion defect was visualized at 6 hours but the extent was largely decreased at 1 week. Delayed contrast enhancement MRI (DE-MRI) demonstrated hyperenhancement within the target area at 6 hours but not at 1 week. The microinfarcts on gross specimen stained with nitrobluetetrazolium chloride were invisible to the naked eye and only detectable microscopically. Increased cTnT was observed at 6 hours and 1 week after microembolization.

Conclusion

Coronary microembolization induced by a certain load of small-sized microemboli may result in microinfarcts invisible to the naked eye with normal epicardial coronary arteries. MRI features of myocardial impairment secondary to such microembolization include the decline in left ventricular function and myocardial perfusion at cine and first-pass perfusion imaging, and transient hyperenhancement at DE-MRI.     

特发性室性期前收缩患儿心率变异性和心率减速力的研究

目的探讨不同起源特发性室性期前收缩患儿的心率变异性(HRV)与心率减速力(DC)各项指标的关联性。方法回顾性分析155例特发性室性期前收缩患儿的临床资料,按不同年龄组分为婴幼儿期(3岁),学龄前期组(3~6岁)和学龄期(~16岁),并在不同年龄组内按室性期前收缩来源部位不同,分为右室型组和左室型组;比较分析不同年龄组、不同来源期前收缩组之间HRV与DC各指标的差异。结果三个不同年龄组的DC和HRV时域分析各项参数的差异均有统计学意义(P0.05)。婴幼儿组中,右室型组和左室型组间相邻RR间期差值的均方根(RMSSD)、高频功率(HF)、低频功率(LF)/HF、DC、相邻RR间期差值50 ms的百分数(PNN50)差异均有统计学意义(P均0.05);学龄前期组中,右室型组和左室型组间的RMSSD、LF、HF、LF/HF、DC差异有统计学意义(P均0.05),学龄期组中,右室型组和左室型组间的RMSSD、HF、LF/HF、DC差异均有统计学意义(P均0.05)。结论特发性室性期前收缩患儿自主神经平衡调节受损,以迷走神经张力的降低为主;起源于优势心室(婴幼儿期及学龄前期患儿以右心室占优势,学龄期患儿左心室为优势心室)的频发室性期前收缩,增加了恶性心律失常发生的风险。     

Experimental muscle pain results in reorganization of coordination among trapezius muscle subdivisions during repetitive shoulder flexion

The aim of the study was to examine the effect of experimental unilateral upper trapezius muscle pain on the relative activation of trapezius muscle subdivisions bilaterally during repetitive movement of the upper limb. Surface EMG signals were detected from nine healthy subjects from the upper, middle and lower divisions of trapezius during a repetitive bilateral shoulder flexion task. Measurements were performed before and after injection of 0.5 ml hypertonic (pain condition) and isotonic (control) saline into the upper division of the right trapezius muscle in two experimental sessions. On the painful side, upper trapezius showed decreased EMG amplitude (average rectified value, ARV) and lower trapezius increased ARV throughout the entire task following the injection of hypertonic saline (40.0 ± 22.2 vs. 26.0 ± 17.4 μV, and 12.5 ± 7.6 vs. 25.6 ± 14.8 μV, respectively, at the beginning of the contraction). On the side contralateral to pain, greater estimates of ARV were identified for the upper division of trapezius as the task progressed (37.4 ± 20.2 vs. 52.7 ± 28.4 μV, at the end of the contraction). Muscle fiber conduction velocity did not change with pain in all three divisions of the right trapezius muscle. The results suggest that local elicitation of nociceptive afferents in the upper division of the trapezius induces reorganization in the coordinated activity of the three subdivisions of the trapezius in repetitive dynamic tasks.