The effect of feet position on standing balance in patients with diabetes.

Feet displacement is recognized to be an important element in standing and is also linked to postural instability in elderly people with diabetes. This study investigates standing balance in diabetic patients in four asymmetric feet displacements. Quiet standing balance was investigated using the Biodex Balance System in 18 diabetic patients and compared with 18 control elderly subjects. The four standing conditions, namely, comfortable feet position, preferred feet position with a stance width of 17 cm and 15° angle between the medial borders, feet side by side, and heel side by side with a 30° angle between medial edges of feet were evaluated (i.e. eyes opened, eyes closed). The overall stability was calculated by measuring anterior-posterior and medial-lateral indices in standing conditions. Differences among feet positions were compared using an analysis of variance and the independent t-test. The diabetic patients were unstable in the medial-lateral direction when standing with feet side by side versus heel side by side with a 30° angle between medial edges of feet (p = 0.012 and 0.011, respectively), while in controls the anterior-posterior stability scores between standing in preferred foot position with stance width of 17 cm and 15° angle between the medial borders versus feet side by side, and heel side by side with a 30° angle between medial edges of feet versus preferred foot position with stance width of 17 cm and 15° angle between the medial borders had significant difference (p < 0.05). The anterior-posterior stability scores of diabetic subjects with feet side by side versus comfortable foot position (p = 0.047) and heel side by side with a 30° angle between medial edges of feet versus comfortable foot position (p = 0.016) when they closed their eyes during the test had significant difference. Results confirmed that diabetic patients have greater instability in the medial-lateral direction when the base of support reduces and visual clue has an important role in standing balance. © IMechE 2014.