Reduced degrees of freedom of finger movements in multiple sclerosis patients with impaired hand function – a TMS study

Hand function may be impaired in patients suffering from multiple sclerosis (MS), but the pathophysiology underlying this impairment is poorly understood. Previously, we showed that finger movements evoked by transcranial magnetic stimulation (TMS) exhibit modular properties suggesting that the central nervous system provides efficient control of finger movements by combining flexibly a limited number of joint synergies. We sought to examine how this mode of operation is affected in MS. We compared TMS-evoked movements of 20 MS patients (age 38.7±8.8; 16 female; EDSS 3.1±1.6) to 20 age and sex matched healthy co…