Predictive Value of Somatosensation for Manual Dexterity and Upper Limb Motor Function in Stroke Survivors

Objectives: One of the most disabling impairments following stroke is upper limb impairment. Despite the important role of somatosensory function in motor control and high prevalence of somatosensory deficits in stroke survivors, little attention has been paid to its effect on UE motor function in chronic stroke survivors. Thus, the aim of this study is to explore the correlation between different somatosensations and manual dexterity as well as UE motor function in these patients. Methods: In this correlational study, ۲۲۵ chronic stroke survivors (۱۱۲ female and ۱۱۳ male) participated, selected by simple non-probability method among the stroke survivors admitted to the rehabilitation centers in Tehran. The lower-order somatosensations, including light touch and wrist Proprioception, were evaluated by Weinstein Enhanced Sensory Test (WEST) and Wrist Position Sense Test (WPST), respectively. The higher-order somatosensations were measured by static and moving ۲-Point Discrimination (s۲PD and m۲PD, respectively), Hand Active Sensation Test (HAST) and Haptic Object Recognition Test (HORT). Gross and fine manual dexterity and UE motor function were assessed using Box-Block Test (BBT), Purdue Pegboard Test (PPT) and Wolf Motor Function Test (WMFT), respectively. Results: The multiple regression models showed that WPST alone accounted for the ۳۸.۸%- ۵۶.۶% of the variance in manual dexterity and UE motor function. The WEST was the second most significant predictor in all regression models. The HORT, m۲PD and HAST explained a small percent of the variance in regression models.  Discussion: These results suggest that treatments that target somatosensory impairments, especially wrist Proprioception and light touch, may be particularly important for improving manual dexterity and UE motor function in chronic stroke survivors.

Keywords:

Correlation , Motor activity , Somatosensory disorders , Stroke , Upper extremity