Pain-Induced Impact on Movement: Motor Coordination Variability and Accuracy-Based Skill

Studies on pain are generally conducted for two purposes: first, to study patients with pain who have physical changes due to nerve and muscle lesions, and second, to regain the appropriate kinematic post-pain pattern. The present study aimed to investigate the effect of pain on the coordination variability pattern and throw accuracy. Participants included 30 people with a mean age of 18-25 years who volunteered to participate in the study. Individuals were randomly divided into three groups of local pain, remote pain, and control group. Without pain, participants practiced and acquired skills in 10 blocks of 15 trials. In the retention and transition phase, which were associated with pain, in their respective groups, included 1 hour, 24- hour, and 1- week acquisition; they were re-tested twice in a 15-block trial, which was once with and without pain. The results revealed that pain did not affect the throwing accuracy (p = 0.469). Besides, in the phase of decreasing acceleration in throwing, movement variability pattern in the pain-related groups in the shoulder and elbow joints (p = 0.000), elbow and wrist (p = 0.000), were more than the painless groups. Based on the results, it can be said that the increase in variability in pain-related groups is due to the different strategies and patterns that individuals use to avoid pain. Also, despite the pain, the nervous system attempts to increase the variability find the least painful pattern of movement and reduces this variability over time and using a repetitive pattern.