Plantar tissue thickness is related to peak plantar pressure in the high-risk diabetic foot

OBJECTIVE - To investigate the relationship among plantar foot pressure, pl antar subcutaneous tissue thickness, severity of neuropathy (vibration perc eption threshold [VPT]), callus, and BMI in a large group of neuropathic di abetic patients at risk of foot ulceration. RESEARCH DESIGN AND METHODS - A total of 157 diabetic neuropathic patients (VPT > 25 V) without either peripheral vascular or ulcer history were studi ed. Plantar foot pressure and plantar tissue thickness were measured at eac h metatarsal head (MTH) using an optical pedobarograph and an ultrasound sc anning platform, respectively. RESULTS- A significant association was observed between peak plantar pressu re and plantar tissue thickness at all MTHs (-0.26 < r < -0.61, P < 0.0001) , with the least pronounced association at the first MTH. In addition, the pressure lime integral was significantly associated with plantar tissue thi ckness (-0.24 < r < -0.57, P < 0.0001). BMI was significantly related to pl antar tissue thickness (0.18 < r < 0.45, P < 0.05), but not to peak forefoo t pressures. Subjects with callus had significantly reduced plantar tissue thickness at all MTHs except the first MTH and increased peak pressures at all MTHs (P < 0.001). CONCLUSIONS - This study confirms a strong inverse relationship between pla ntar tissue thickness and dynamic foot pressure measurements. Long-term fol low-up of this patient population will confirm whether reduced plantar tiss ue thickness predicts the development of diabetic foot ulcers.