Changes in the distribution of plantar pressure in diabetic patients with forward and backward walking

Abstract

Objective To observe the plantar pressure distribution of type 2 diabetic patients in forward walking and backward walking, explore the significance of backwarding that may exit. Methods A total of 114 patients with type 2 diabetes (DM group, male 58, female 66 cases, age(53±11)yrs) were recruited from June 2011 to May 2012. Eighty-three healthy people (DC group, male 40, female 43 cases, age(51±13)yrs) were compared during the same period. The plantar pressure distribution was measured by foot peak pressure and impulse in the forward walking and backward walking. Two-sample t test was used for statistical analysis. Results (1)Forward walking: compared with the control group, the peak foot pressure in the metatarsal 1, 3(M1, M3), heel medial(HM) were increased in the diabetic group. The highest pressure was at M3 (left foot: the control group (16.5±2.0) N/cm2, diabetic group (21.9±5.0) N/cm2; right foot: the control group (18.2±2.8) N/cm2, diabetic group (19.4±4.4) N/cm2, the difference was statistically significant(t=-10.46, -2.31, both P<0.05)). (2)Forward walking: compared with control group, the impulse increased in the toe 1(T1), metatarsal 1 to 5(M1 to M5), foot central arch or mid foot(MF), heel medial(HM) and heel lateral(HL)in diabetic group, especially in the M3 area (left foot: (50±11)N·s in the control group, (87±21)N·s in the diabetic group; right foot: the control group (62±15)N·s, diabetic group (84±19)N·s, t=-16.24, -8.60, both P<0.05). (3) Compared with forward walking, the peak pressure at T1, toe 2-5(T2-5), M1, MF, HM and HL had different degrees of increase in the diabetic patients with backward walking, but the peak pressure was significantly reduced in M3 (left foot were (22±5), (12±5) N/cm2, right foot were (19±4), (15±6) N/cm2 , t=15.10, 5.61, both P<0.05). (4)Compared with forward walking, the impulse was increased in T1 and T2-5 areas in the diabetic group with backward walking, especially in T1 zone(left foot: (54±18), (81±16) N·s, right foot: (29±11), (75±18) N·s , t=-11.85, -23.90, both P<0.05); but the impulse at M2, M3, M4 was less than the same parts of impulse at the forward walking, especially in M3 zone(left foot: (87±21), (61±18) N·s, right foot: (84±19), (59±18) N·s, t=9.82, -9.63, both P<0.05). Conclusions Compared with normal subjects, the plantar peak pressure and impulse distribution in patients with diabetes are different. Backward walking may improves the plantar pressure distribution of diabetic patients. Key words: Diabetes mellitus, type 2; Walking; Foot Pressure