DIFFERENCES IN JOINT MOBILITY AND FOOT PRESSURES BETWEEN BLACK-AND-WHITE DIABETIC-PATIENTS

Limited joint mobility is common in diabetes and is related to high foot pressures and foot ulceration. We have examined the differences in joint mobility and foot pressures in four groups matched for age, sex, and duration of diabetes: 31 white diabetic, 33 white non-diabetic, 24 black diabetic, and 22 non-diabetic black subjects. Joint mobility was assessed using a goniometer at the fifth metacarpal, first metatarsal, and subtalar joints. In-shoe and without shoes foot pressures were measured using an F-Scan system. Neuropathy was evaluated using clinical symptoms (Neuropathy Symptom Score), signs (Neuropathy Disability Score), and Vibration Perception Threshold. There was no difference between white and black diabetic patients in Neuropathy Symptom Score, Neuropathy Disability Score, and Vibration Perception Threshold. Subtalar joint mobility was significantly reduced in white diabetic patients (22 +/- 7 degrees) compared to white controls (26 +/- 4 degrees, black diabetic patients (25 +/- 5 degrees), and black controls (29 +/- 7 degrees), and increased in black controls compared to white controls and black diabetic patients (level of statistical significance p < 0.05). Without shoes foot pressures were higher in white diabetic patients (8.31 +/- 400 kg cm(-2)) compared to white controls (6.81 +/- 2.31 kg cm(a2)), black diabetic patients (6.2 +/- 2.53 kg cm(-2)) and black controls (5.00 +/- 1.24 kg cm(-2)) and lower in black controls compared to white and black diabetic patients (p< 0.05 in all cases). We conclude that racial differences exist in joint mobility and foot pressures between black and white subjects. Thus, in black diabetic patients the joint mobility, although reduced compared to black healthy subjects, is increased when compared to white diabetic patients. This contributes to lower foot pressures, comparable to non-diabetic white subjects and probably reduces the risk of foot ulceration in black diabetic patients.