Tsai Yi-Jung, Tu Yuan-Kun, Hsiao Chih-Kun, Su Fong-Chin
Department of Biomedical Engineering, National Cheng Kung University, Tainan, Taiwan; Medical Device Innovation Center, National Cheng Kung University, Tainan, Taiwan.
Department of Orthopedics, E-DA Hospital, Kaohsiung, Taiwan.
J Hand Surg Am. 2015 Jun;40(6):1196-201. doi: 10.1016/j.jhsa.2015.01.043. Epub 2015 Mar 24.
To quantify the smallest real difference (SRD) of muscle strength in patients with brachial plexus injuries (BPI) after nerve transfer.
This study enrolled 16 patients with BPI who had C5-C6 and C5-C7 root injuries and who received nerve transfer of the spinal accessory nerve to the suprascapular nerve and fascicles of the ulnar nerve to the branch of the musculocutaneous nerve that innervates the biceps muscle. The quantitative peak strength of the shoulder abductor, external rotator, and elbow flexor in both arms were measured by the hand-held dynamometer. The SRD of each muscle was determined from the values of the intraclass correlation coefficient and standard error of measurement.
In the involved arm, peak strength ranged from 18% of the noninvolved (shoulder external rotator) to 40% of the noninvolved (shoulder abductor). The intraclass coefficient for within-session reliability revealed good to excellent reliability for muscles, ranging from 0.86 to 0.99 and 0.87 to 0.91 in the involved and noninvolved arms, respectively. The SRD values were low for the shoulder external rotator (2.6 kg) and high for the elbow flexor (3.3 kg).
The hand-held dynamometer is a device with good to excellent reliability for measuring the objective strength of patients with BPI in a single session. The SRD values established in the current study are more applicable for patients achieving a Medical Research Council grading of 3 or higher and can be used to detect real changes occurring after intervention, which can thereby differentiate real changes from changes that could be attributed to random variation in the measurements.
TYPE OF STUDY/LEVEL OF EVIDENCE: Diagnosis II.
量化臂丛神经损伤（BPI）患者神经移位术后肌肉力量的最小真实差异（SRD）。
本研究纳入了16例BPI患者，这些患者存在C5 - C6和C5 - C7神经根损伤，接受了副神经至肩胛上神经的神经移位以及尺神经束至支配肱二头肌的肌皮神经分支的神经移位。使用手持测力计测量双臂的肩外展肌、外旋肌和肘屈肌的定量峰值力量。根据组内相关系数和测量标准误差值确定每块肌肉的SRD。
在患侧手臂中，峰值力量范围从健侧的18%（肩外旋肌）到40%（肩外展肌）。组内会话可靠性的组内系数显示，肌肉的可靠性良好至极佳，患侧和健侧手臂分别为0.86至0.99和0.87至0.91。肩外旋肌的SRD值较低（2.6千克），肘屈肌的SRD值较高（3.3千克）。
手持测力计是一种在单次会话中测量BPI患者客观力量具有良好至极佳可靠性的设备。本研究确定的SRD值更适用于医学研究委员会评分为3或更高的患者，可用于检测干预后发生的真实变化，从而将真实变化与测量中的随机变化区分开来。
研究类型/证据水平：诊断性研究II级。
