肌萎缩侧索硬化伴认知功能障碍的研究进展

认知功能障碍在肌萎缩侧索硬化（ALS）患者中是普遍存在的，ALS伴认知功能障碍常提示预后不良。近年来对ALS患者认知功能障碍的研究取得了一定的进展，本文对ALS伴认知功能障碍的临床特点、生物标志物、遗传学特征和最新治疗进展进行综述，以期为ALS伴认知功能障碍的临床诊疗提供新思路。     

Enlarged high frequency oscillations of the median nerve somatosensory evoked potential and survival in amyotrophic lateral sclerosis

ObjectiveA large N20 and P25 of the median nerve somatosensory evoked potential (SEP) predicts short survival in amyotrophic lateral sclerosis (ALS). We investigated whether high frequency oscillations (HFOs) over N20 are enlarged and associated with survival in ALS.MethodsA total of 145 patients with ALS and 57 healthy subjects were studied. We recorded the median nerve SEP and measured the onset-to-peak amplitude of N20 (N20o-p), and peak-to-peak amplitude between N20 and P25 (N20p-P25p). We obtained early and late HFO potentials by filtering SEP between 500 and 1 kHz, and measured the peak-to-peak amplitude. We followed up patients until endpoints (death or tracheostomy) and analyzed the relationship between SEP or HFO amplitudes and survival using a Cox analysis.ResultsPatients showed larger N20o-p, N20p-P25p, and early and late HFO amplitudes than the control values. N20p-P25p was associated with survival periods (p = 0.0004), while early and late HFO amplitudes showed no significant association with survival (p = 0.4307, and p = 0.6858, respectively).ConclusionsThe HFO amplitude in ALS is increased, but does not predict survival.SignificanceThe enlarged HFOs in ALS might be a compensatory phenomenon to the hyperexcitability of the sensory cortex pyramidal neurons.     

Effects of anteriorly-loaded treadmill walking on dynamic gait stability in young adults

BackgroundAnteriorly-loaded walking is common in many occupations and may increase fall risk. Dynamic gait stability, defined by the Feasible Stability Region (FSR) theory, quantifies the kinematic relationship between the body’s center of mass (COM) and base of support (BOS). FSR-based dynamic gait stability has been used to evaluate the fall risk.Research questionHow does front load carriage affect dynamic gait stability, step length, and trunk angle among young adults during treadmill walking?MethodsIn this between-subject design study, 30 healthy young adults were evenly randomized into three load groups (0%, 10%, or 20% of body weight). Participants carried their assigned load while walking on a treadmill at a speed of 1.2 m/s. Body kinematics were collected during treadmill walking. Dynamic gait stability (the primary variable) was calculated for two gait events: touchdown and liftoff. Step length and trunk angle were measured as secondary variables. One-way analysis of variance was conducted to detect any group-related differences for all variables. Post-hoc analysis with Bonferroni correction was performed when main group differences were found.ResultsNo significant differences but medium to large effect sizes were found between groups for dynamic gait stability at touchdown (p = 0.194, η² = 0.114) and liftoff (p = 0.122, η² = 0.139). Trunk angle significantly increased (indicating backward lean) with the front load at touchdown (p < 0.001, η² = 0.648) and liftoff (p < 0.001, η² = 0.543). No significant between-group difference was found related to the step length (p = 0.344, η² = 0.076).SignificanceCarrying a front load during walking significantly alters the trunk orientation and may change the COM-BOS kinematic relationship and, therefore, fall risk. The findings could inform the design of future studies focusing on the impact of anterior load carriage on fall risk during different locomotion.     

The apex angle of the rocker sole affects the posture and gait stability of healthy individuals

BackgroundRocker sole (RS) shoes have been linked to impaired postural control. However, which features of RS design affect balance is unclear.Research questionWhich RS design features affect standing balance and gait stability?MethodsThis study utilized an intervention and cross-over design. Twenty healthy young adults (10 males and 10 females) participated in this study. Standing balance and gait stability were measured using a single force platform and three-dimensional motion analysis system, respectively. The experimental conditions included the control shoe and five RS shoes in the combination of apex position (%) and apex angle (degree) for RS50-95, RS60-95, RS70-95, RS60-70, and RS60-110. The main outcome measures were the area surrounding the maximal rectangular amplitude, mean path length, average displacement of the center of pressure along the lateral and anterior/posterior directions, and maximal center of pressure excursion as the standing balance and lateral margin of stability as the gait stability. Statistical analyses were conducted using a two-way split-plot analysis of variance with repeated measures (with RS design as the within-subject factor and sex as the between-subject factor) and the Bonferroni post hoc test (α = .05).ResultsRegarding the mean path length, RS60-70 was significantly longer than the control shoe, and it showed a significantly increased lateral margin of stability. Thus, RS60-70 was shown to affect standing balance, limit of stability, and gait stability of the frontal plane during gait.SignificanceThese results suggest that the apex angle of the RS design feature affects standing balance and gait stability, and RS60-70 is detrimental to stability. Therefore, when RS with a small apex angle is prescribed, it is necessary to consider the patient’s balance ability.     

Comparison of screw fixation versus non-fixation in dorsal opening wedge medial cuneiform osteotomy of adult acquired flatfoot

BackgroundThe aim of this study was to compare the radiographic and functional results between fixation and non-fixation in the Cotton osteotomy for the treatment of adult acquired flatfoot.MethodsA retrospective, case-controlled study of consecutive stage IIB posterior tibial tendon dysfunction (PTTD) patients treated with the same bony reconstructive surgery including cotton osteotomy between 2013 and 2017. Meary’s angle, the medial arch sag angle (MASA), and medial cuneiform cobb angle (MCCA) were evaluated pre-operation, at first weight bearing after surgery, and 12 months post operation.ResultsForty feet were included in the study. The cotton osteotomy utilized screw fixation (n = 20) or non-fixation technique (n = 20). No significant differences between groups were found in pre-operative and follow-up radiographic parameters, union rate, and functional results.ConclusionThe non-fixation with press fit technique is a reliable procedure for Cotton osteotomy and as effective as screw fixation.Level of evidenceLevel III, case control study     

Relationship between EMG-detected and ultrasound-detected fasciculations in amyotrophic lateral sclerosis: A prospective cohort study

ObjectivesFasciculation potentials (FP) are an important consideration in the electrophysiological diagnosis of ALS. Muscle ultrasonography (MUS) has a higher sensitivity in detecting fasciculations than electromyography (EMG), while in some cases, it is unable to detect EMG-detected fasciculations. We aimed to investigate the differences of FP between the muscles with and without MUS-detected fasciculations (MUS-fas).MethodsThirty-one consecutive patients with sporadic ALS were prospectively recruited and in those, both needle EMG and MUS were performed. Analyses of the amplitude, duration, and number of phases of EMG-detected FPs were performed for seven muscles per patient, and results were compared between the muscles with and without MUS-fas in the total cohort.ResultsThe mean amplitude and phase number of FP were significantly lower in patients with EMG-detected FP alone (0.39 ± 0.25 mV and 3.21 ± 0.88, respectively) than in those with both FP and MUS-fas (1.22 ± 0.92 mV and 3.74 ± 1.39, respectively; p < 0.0001 and p = 0.017, Welch’s t-test).ConclusionSmall FP may be undetectable with MUS. MUS cannot replace EMG in the diagnostic approach for ALS.SignificanceClinicians should use a combination of EMG and MUS for the detection and quantitative analysis of fasciculation in ALS.     

调整Kappa角及光学切削直径对准分子激光原位角膜磨镶术后的影响

目的　评价调整光学切削直径及Kappa角后对准分子激光原位角膜磨镶术（laser in situ keratomileusis，LASIK）后效果的影响。方法　选取2017年1月至12月在我院行LASIK手术的高度近视患者313例（626眼），根据切削直径分成两组，试验组157例314眼，切削直径设定为6.0 mm，对照组156例312眼，切削直径设定为6.5 mm。试验组患者激光切削前修正Kappa角，对照组不做修正。患者术前进行裸眼视力、主视眼确定、验光、眼压、暗室下瞳孔直径、泪液分泌试验、裂隙灯、散瞳验光、眼底检查、pentacam测量角膜厚度、角膜地形图测量角膜前后表面及Kappa角等检查。术后1 d、1周、1个月随访，并检查裸眼视力、角膜厚度、波前像差及夜间视力、光晕、眩光等情况。比较两组患者角膜厚度变化、手术所用时间以及两组患者术后的高阶像差的差异。结果　试验组与对照组患者年龄分别为18～44（24.19±5.33）岁、18～42（25.08±4.91）岁，屈光度分别为（-7.47±1.04）D、（-7.61±1.12）D。两组年龄、屈光度比较差异均无统计学意义（均为P>0.05）。试验组与对照组患者术前Kappa角分别为，X轴:（210±40）μm、（200±30）μm，Y轴:（190±30）μm、（220±40）μm，差异无统计学意义（P=0.210）。两组手术前后的角膜厚度及术后角膜基质床的厚度差异均无统计学意义（均为P>0.05）。试验组与对照组的手术时间分别为（15.56±1.89）s和（20.83±3.03）s，差异有统计学意义（P=0.000）。试验组的总高阶像差和垂直慧差的变化均明显低于对照组（均为 P<0.01），但两组间的水平慧差差异无统计学意义（P>0.05），对照组的球差低于试验组（P<0.01）。结论　LASIK手术中科学合理地调整Kappa角可有助于提高患者术后的视觉质量。     

颞下颌关节强直动物模型中最大张口度与强直严重程度关系研究

目的　研究主、被动最大张口度（AMMO、PMMO）与颞下颌关节强直严重程度的关系。方法　选取28只健康雄性绵羊随机分为实验组和对照组，每组各14只。实验组绵羊双侧颞下颌关节模拟髁突矢状骨折，其中左侧翼外肌被切断以阻断其功能；对照组绵羊未进行手术。于术前及术后12、24周对所有绵羊体重、AMMO、PMMO、颞下颌关节形态学特点进行测量评估。结果　实验组只有右侧保留翼外肌功能的颞下颌关节发生了骨强直。术后12、24周，实验组绵羊AMMO、PMMO、极限距离均显著低于对照组，差异均有统计学意义（均P < 0.05）。实验组绵羊AMMO和PMMO与骨融合区宽度、长度、面积及钙化程度均呈负相关（均P < 0.05），其中骨融合区面积为主要影响因素（术后12、24周相关系数r分别为-0.94、-0.95）。结论　颞下颌关节强直动物模型中阻断翼外肌功能可阻止骨强直的发生；对于早期髁突矢状骨折，可通过牙合垫或牙合板进行张口训练，进而阻断翼外肌功能。当颞下颌关节发生骨强直时，骨融合区面积越大，张口受限越明显。