Effect of Experimental Pain Induced by Electrical Stimulation on Static and Dynamic Balance Test Results

Patients often report experiencing pain, which can impose cognitive demands and affect balance. This cognitive burden may impact the ability to maintain a stable standing position during dual-tasking. This study aimed to investigate standing postural sway in healthy adults under electrical stimulation-induced pain.

Twenty-one participants, including 12 men and 9 women, were included in this study. Static and dynamic balance tests were conducted using a force plate. Electrodes from the Silver Spike Point electrotherapy device were attached to the inferior end of the ulnar styloid. The static balance test involved standing on the force plate, while the dynamic balance was assessed through a cross-test under two conditions: with and without electrical stimulation. Electrical stimulation was delivered using a transcutaneous electrical nerve stimulation unit at an intensity that elicited a pain level of 5 on a numerical rating scale, as reported by the participants. Four tests, including static balance (with stimulus), static balance (without stimulus), cross (with stimulus), and cross (without stimulus), were each performed twice in a random order. Statistical analyses were performed to compare all variables between the control (without stimulus) and intervention (with stimulus) groups.

The static balance test showed a significantly reduced sway path length (37.16 cm without stimulation vs. 33.29 cm with stimulation). The dynamic balance test (cross-test) revealed no significant differences.

Healthy adult participants under electrical stimulation-induced pain had lower static standing sway. However, the dynamic balance test did not show significant changes even with the addition of electrical stimulation.