Department of Orthopedic Surgery, Division of Orthopedic Research, Mayo Clinic, Rochester, MN 55902, USA.
J Electromyogr Kinesiol. 2013 Aug;23(4):924-9. doi: 10.1016/j.jelekin.2013.03.010. Epub 2013 Apr 30.
Activity monitors provide an objective mechanism for evaluating patient function. It is unclear what similarities or unique information may be yielded using different analyses. Fifteen patients scheduled to undergo shoulder arthroplasty and fifteen matched control subjects wore tri-axial accelerometer activity monitors bilaterally at the lower (wrist) and upper (biceps) arm for 3days. Measures of central tendency, variance, sample entropy, and asymmetry were calculated. A novel technique to evaluate time distribution of activity intensity was also performed. Within both groups there was a difference in central tendency and variance when comparing dominant and non-dominant limbs for both the lower (
Mean Activity, P<0.001; Max Activity, P<0.001;
Mean Activity, P=0.044; Max Activity, P=0.009) and upper (
Mean Activity, P<0.001; Max Activity, P=0.046;
Mean Activity, P=0.002; Max Activity, P=0.049) arm. Within group differences were also present for lower arm entropy in both groups (CONTROLS, P<0.001; PATIENTS P=0.041), and at the upper arm for patients (P=0.003). There were differences between groups for the asymmetry index for both the lower (P=0.033) and upper arm (P=0.005), and maximum activity level of the lower arm (P=0.05). Between group differences were present for time distribution of activity intensity, as the involved upper arm of patients was inactive for a greater time than controls (P=0.013). These results highlight unique information provided by multiple analysis methods, and include a novel approach of evaluating the distribution of time spent across variable intensity activities.
活动监测器为评估患者功能提供了客观的机制。目前尚不清楚使用不同的分析方法可能会产生哪些相似或独特的信息。15 名计划接受肩部关节置换术的患者和 15 名匹配的对照者在 3 天内分别在双侧下臂（手腕）和上臂（肱二头肌）佩戴三轴加速度计活动监测器。计算了中心趋势、方差、样本熵和不对称性的测量值。还采用了一种评估活动强度时间分布的新技术。在两组中，无论是对优势侧还是非优势侧，下臂（对照组：平均活动，P<0.001；最大活动，P<0.001；患者：平均活动，P=0.044；最大活动，P=0.009）和上臂（对照组：平均活动，P<0.001；最大活动，P=0.046；患者：平均活动，P=0.002；最大活动，P=0.049），都存在中心趋势和方差的差异。在两组中，下臂的熵也存在组内差异（对照组，P<0.001；患者，P=0.041），而在上臂仅患者存在差异（P=0.003）。两组的下臂不对称指数（P=0.033）和上臂（P=0.005）以及下臂最大活动水平（P=0.05）均存在差异。两组之间的活动强度时间分布也存在差异，因为患者的受累上臂的无活动时间比对照组长（P=0.013）。这些结果突出了多种分析方法提供的独特信息，包括评估不同强度活动时间分布的新方法。
