Tibialis Anterior electromyographic analysis during fast dorsiflexion: Relationship with recovery of gait, muscle strength and evoked potentials during subacute spinal cord injury

Neurorehabilitation of voluntary motor function after incomplete spinal cord injury (iSCI) is often performed without periodic analysis of electromyographic (EMG) parameters, such as amplitude, integrated muscle activity and duration of contraction. The main objective of this study was to validate the diagnostic potential of the analysis of Tibialis Anterior (TA) activity to detect functional recovery in subjects with subacute iSCI. In this study the recovery of voluntary motor function was assessed at 2 week intervals during subacute iSCI, by measuring the TA muscle activity during maximum dorsiflexion velocity (MDV). In addition, other functional and neurophysiologic parameters have been assessed, such as muscle strength, voluntary torque generation, gait function improvement, and TA motor evoked potentials. The study demonstrated that muscle strength, voluntary torque generation and gait function significantly improved during the follow up, in addition to an increase in TA EMG amplitude and a reduction in TA muscle contraction duration. TA EMG amplitude correlated with motor evoked potentials, torque and muscle balance, while short muscle duration correlated with gait function. To conclude, longitudinal assessment of limited recovery of voluntary function during subacute iSCI can be detected with specific TA EMG parameters analysis during controlled movement, providing relevant diagnostic information during neurorehabilitation.