Prediction of motor disorders in multiple sclerosis using muscle change structure assessment

The neuropathogenesis of multiple sclerosis (MS) lesions has been explained by several mechanisms, which emphasize the unpredictable nature of these lesions. The aim of this study is to present the neuromuscular changes in MS at the patients without gait or motor disorders using a noninvasive method named tensiomyography (TMG).

The studied group included a number of seven MS patients without clinically detected gait disorders, with mean age of 33.28 years (min. 22 years-max. 60 years), diagnosed with progressive multiple sclerosis with relapses - three patients and with relapsing-remitting multiple sclerosis (RRMS). They have been evaluated using clinical, functional scales for evaluation and neuromuscular assessment using TMG parameters (displacement Dm, contraction time - Tc, delay time - Td, supporting time - Ts, relaxation time - Tr), for rectus femoris (mRF).

The group with MS patients recorded functional asymmetries with higher values in the left lower limb. We determined Tc values lower than the minimum normally required, which meant that in the group with MS there was an increase in the percentage of type II fibers. Other TMG parameters show important difference between left and right side even if they do not have gait disorders.

These patients with MS underwent modifications in their muscle tone, muscle strength and other changes related to the presence or absence of muscle atrophy. The muscle tone could be affected by the muscle atrophy or hypertrophy. In conclusion, this type of assessment performs the non-invasive assessment of contractile properties of the muscles, without the integration of the tendon properties, joint mechanics or connective tissue in the mechanical response to muscle deformation produced by electrical stimulation.