Grabiner M D, Jeziorowski J J
Department of Biomedical Engineering and Applied Therapeutics, Cleveland Clinic Foundation, Cleveland, Ohio, USA.
Clin Biomech (Bristol). 1992 Nov;7(4):195-200. doi: 10.1016/S0268-0033(92)90001-K.
This investigation compared the ability of a previously defined, non-standard isokinetic variable set to that of standard isokinetic variables to discriminate trunk extension performance of control subjects from subjects with a history of low back pain. Ten male subjects with history of low back pain, asymptomatic at the time of the test, and nine subjects without history of low back pain participated in a single session, test-retest protocol. The test and retest each consisted of five maximum effort isokinetic trunk extension-flexion repetitions at 60, 120, and 180 deg s(-1). At each isokinetic speed, eight isokinetic trunk extension performance variables were extracted and the mean value for each calculated from Trials 2, 3, and 4. The set of 48 variables was reduced to seven, demonstrating intergroup differences at the selected criterion probability level (P<0.025). These variables were submitted to a stepwise discriminant analysis that eliminated one variable, generated a significant discriminant function (P = 0.005), and correctly categorized 100% of the control and low back pain patients. The variables satisfying the entry criterion into the discriminant analysis were from the 120 and 180 deg s(-1) conditions, suggesting that residual functional deficits related to trunk extensor muscular power generation are associated with low back pain. For comparison purposes, secondary discriminant analyses using standard isokinetic variables were conducted but the results were statistically and clinically inferior to those of the initial discriminant function. The results of this study imply that rehabilitation from low back dysfunction should include a component of muscular power restoration. The present results can offer no resolution to the clinical question related to the cause of the power deficit. This type of inquiry will require the use of additional technologies such as electromyography that can lend insight into agonist-antagonist relationships.
本研究比较了先前定义的非标准等速变量集与标准等速变量区分对照组受试者和有腰痛病史受试者躯干伸展表现的能力。十名有腰痛病史且在测试时无症状的男性受试者和九名无腰痛病史的受试者参与了单节次、重测方案。测试和重测各包括在60、120和180度/秒（-1）下进行五次最大努力的等速躯干伸展-屈曲重复动作。在每个等速速度下，提取八个等速躯干伸展表现变量，并计算试验2、3和4中每个变量的平均值。48个变量的集合被缩减为7个，在选定的标准概率水平（P<0.025）下显示出组间差异。这些变量被进行逐步判别分析，该分析消除了一个变量，生成了一个显著的判别函数（P = 0.005），并正确地将100%的对照组和腰痛患者进行了分类。满足判别分析纳入标准的变量来自120和180度/秒（-1）的条件，这表明与躯干伸肌力量产生相关的残余功能缺陷与腰痛有关。为了进行比较，使用标准等速变量进行了二次判别分析，但结果在统计学和临床上均不如初始判别函数。本研究结果表明，腰痛功能障碍的康复应包括肌肉力量恢复的部分。目前的结果无法解决与力量缺陷原因相关的临床问题。这类探究将需要使用额外的技术，如肌电图，以深入了解主动肌-拮抗肌关系。
