Improving hand function in chronic incomplete tetraplegia by high-PAS intervention with alternative equipment: a case report

INTRODUCTION: The reproducibility of a paired associative stimulation (high-PAS) protocol, shown to be beneficial for rehabilitation in incomplete spinal cord injury (SCI), was investigated in a different technical environment. Whereas previous studies relied on a specific technical setup for high-PAS, here the protocol was replicated using alternative devices. Differences in technical attributes could influence the replicability of specific output. As the necessary technology is available in many clinical and research settings, validating the protocol across device systems is important for broader implementation of high-PAS in SCI rehabilitation. In this case, a high-PAS protocol was administered over 6 consecutive weeks in a patient with severe chronic incomplete SCI. CASE PRESENTATION: A 32-year-old male with chronic C5 American Spinal Injury Association Impairment Scale C tetraplegia participated in this study. Three muscle-nerve pairs from both upper extremities each received 20-min high-PAS, administered 22 times over 6 weeks. The patient was assessed by an experienced physiotherapist before high-PAS, immediately after it, and 1 month after. The intervention improved muscle strength, hand function, and daily task performance in both upper extremities. DISCUSSION: This study sought to replicate high-PAS improvement of motor and functional scores in a patient with severe chronic incomplete SCI and demonstrated that the results can be successfully recapitulated by alternative devices. The improvement observed was consistent with previous studies and supports applicability in more versatile technical environments.