IntroductionThe study aimed to investigate how pain severity in the shoulder region affects balance ability, postural stability and fall risk.Material and methodsSixty participants with shoulder pain, aged 42.45 ±6.51 years, were assessed using a Visual Analog Scale (VAS); they were divided into 2 subgroups as a mild pain group (group 1) and a moderate/severe pain group (group 2). According to VAS-at rest the mild-pain group included 39 and the moderate/severe-pain group included 21 subjects. According to VAS-during movement, the mild-pain group included 19 and the moderate/severe-pain group included 41 subjects. Balance ability-postural stability, fall risk and fear of falling were assessed by the Sportkat System, Berg Balance Scale (BBS), and Fall Efficacy scale (FES) respectively. Differences of variables between mild pain and moderate/severe pain groups were analyzed by the independent groups t-test in groups conforming to a normal distribution and the Mann-Whitney U test for the variables that did not fit a normal distribution.ResultsA positive relationship was found between VAS-at rest and double-foot static balance test score right-left (RL) ratio, while a negative relationship was found between VAS-at rest and BBS score (p < 0.05). Significant differences were found between right foot static balance left score and RL ratio according to pain at rest (p < 0.05).ConclusionsThe results indicated that shoulder pain severity affects balance parameters. As pain level at rest increases, postural sway increases in a medio-lateral direction, and towards the left while standing on the right foot. Approaches regarding increasing balance and postural instability should be included in physiotherapy and rehabilitation programs of patients with shoulder pain at an early phase to protect patients from balance problems and fall risk.