Dysfunctional variability of post-stroke spastic akinesia in light of rehabilitation dynamics: a retrospective observational comparative study

INTRODUCTION. Akinesia of limb segments does not always clearly determine an unfavorable prognosis for post-stroke motor recovery, which may indicate dysfunctional variability that determines uniform clinical manifestations, but different effectiveness of the rehabilitation protocol. It is advisable to search for additional biomarkers that differentiate the dysfunctional pathogenesis of a similar clinical picture. AIM. Comparison of the effectiveness of motor recovery and spasticity regression after standard and extended (with transcranial neuromodulation) rehabilitation of patients with post-stroke spastic akinesia of the hand with different functional states of the corticospinal tract (CST) in the short term. MATERIALS AND METHODS. A retrospective observational comparative study included 294 subjects (aged 23 to 83 years; 52.4 % men) with post-stroke spastic akinesia of the hand. Based on the resting motor response threshold, motor evoked potential amplitude, and central motor conduction time of the cortical representation of m. Abductor pollicis brevis of the affected hemisphere, the patients were divided into 3 groups: Group 1 complete CST lesion; Group 2 partial CST lesion; Group 3 intact CST. Each group was divided into subgroups, the representatives of which received a standard rehabilitation course with or without repetitive transcranial magnetic stimulation (rTMS). Clinical effectiveness was assessed immediately after the treatment course using the MRC Muscle Scale and mAS. RESULTS. The highest motor recovery effectiveness in a standard rehabilitation (without rTMS) was observed in group 3 (p 0.0167). rTMS increased motor recovery effectiveness in groups 1 (p = 0.015) and 2 (p = 0.02). Spasticity regression was observed in the range of 25.7–32.1 % and did not differ significantly in the compared subgroups. A high positive correlation between cases of motor recovery and spasticity regression was identified in subgroups of Group 3. DISCUSSION. The state of the CST determines not only clinical manifestations, but also the effectiveness of rehabilitation approaches. CONCLUSION. rTMS in CST lesions demonstrates effectiveness in restoring voluntary movements, but does not affect spasticity. With the preservation of CST, the restoration of motor skills and regression of spasticity are associated with and probably caused by the restitution of the corticoreticular tract.