Postural stability of diabetic patients with and without cutaneous sensory deficit in the foot

Postural stability was measured in 50 patients classified into two diabetic groups: insulin-dependent diabetes mellitus (IDDM: n = 27), and diabetic patients with bilateral cutaneous sensory deficit in the foot (CD: n = 23). All patients were matched to 50 non-diabetic controls on age, weight and gender variables. The integrity of cutaneous sensory information at the foot was assessed using a monofilament test. Static and dynamic balance was evaluated using an objective balance test involving computer-controlled dual force platforms enclosed by a visual surround. The apparatus provided six test conditions designed to systematically manipulate or eliminate visual, vestibular or somatosensory information. Scores for the six tests, and a derived composite balance score together with movement strategy scores were used for data analysis. For all six tests and composite score CD patients revealed significant postural instability compared to controls. Additionally, the CD group recorded reduced strategy scores indicating an atypical shift from ankle to hip strategy movement as postural control was stressed. IDDM patient test scores were not significantly different from control data on any pairwise comparison. Results indicated significant balance loss associated with CD putting the individual at increased risk for falling and compromising foot mechanics.