Background and Aim: The calculated parameters of the center of pressure (COP) are suitable indicators for evaluating balance in patients after rehabilitation. Therefore, determining the reliability level of each parameter is a matter of great importance. This study tried to determine the reliability of some parameters of the COP sway in patients with myofascial neck pain in different postural situations.

Materials and Methods: The present study is a test-retest reliability design. Twenty patients with myofascial neck pain performed a single and a double leg test with open and closed eyes on a force plate and with open eyes on foam in three sessions with a 30 minute intervals for 30 seconds. Antero-posterior and medio-lateral sway range, mean velocity and mean area of sway were calculated.

Results: The mean velocity showed high reliability (0.98) in all situations, but the other parameters were variable in different situations.

Conclusions: The results showed that some COP parameters are highly reliable in assessment of patients with myofascial neck pain.

Keywords: Reliability, Myofascial neck pain, Center of pressure, Force plate