Chow John W, Yablon Stuart A, Stokic Dobrivoje S
Center for Neuroscience and Neurological Recovery, Methodist Rehabilitation Center, Jackson, MS, USA.
Center for Neuroscience and Neurological Recovery, Methodist Rehabilitation Center, Jackson, MS, USA.
Clin Neurophysiol. 2017 May;128(5):725-733. doi: 10.1016/j.clinph.2017.02.017. Epub 2017 Mar 2.
To characterize the concurrent activation of rectus femoris (RF) and medial gastrocnemius (MG) muscles (extensor coactivation) during gait in subjects with pronounced resting hypertonia after acquired brain injury (ABI) and examine changes after intrathecal baclofen (ITB) bolus injection.
Magnitude and duration of extensor coactivation during different phases of gait were assessed by recording gait kinematics and activity in bilateral RF and MG muscles in 18 controls and 18 ABI subjects before and at 2, 4, and 6h after a 50-μg ITB injection.
Compared to controls, the magnitude of extensor coactivation was significantly increased in all phases of gait except the single support (p≤0.005), while the duration was significantly prolonged throughout (p≤0.001) in both legs of ABI subjects. After ITB bolus, only the duration of extensor coactivation significantly shortened in the more-affected leg during the late double-support and early swing (p≤0.026).
Extensor coactivation is bilaterally exaggerated during gait in ABI subjects. ITB bolus effectively shortens the extensor coactivation in the more-affected leg during the pre-swing and early swing phases of gait.
Shortening of the prolonged extensor coactivation during gait may serve as an index of neurophysiological response to ITB bolus injection in subjects with ABI.
描述获得性脑损伤（ABI）后静息肌张力明显亢进的受试者在步态中股直肌（RF）和腓肠肌内侧头（MG）肌肉的同时激活情况（伸肌共同激活），并研究鞘内注射巴氯芬（ITB）推注后的变化。
通过记录18名对照者和18名ABI受试者在50μg ITB注射前、注射后2小时、4小时和6小时的步态运动学以及双侧RF和MG肌肉的活动，评估步态不同阶段伸肌共同激活的幅度和持续时间。
与对照者相比，ABI受试者除单支撑期外，步态各阶段伸肌共同激活的幅度均显著增加（p≤0.005），且双腿的持续时间在整个过程中均显著延长（p≤0.001）。ITB推注后，仅在受影响较重的腿上，伸肌共同激活的持续时间在双支撑后期和摆动前期显著缩短（p≤0.026）。
ABI受试者在步态中双侧伸肌共同激活过度。ITB推注可有效缩短受影响较重的腿在步态摆动前期和摆动早期的伸肌共同激活时间。
缩短步态中延长的伸肌共同激活时间可能作为ABI受试者对ITB推注神经生理反应的一个指标。
