Hastings Mary K, Mueller Michael J, Pilgram Thomas K, Lott Donovan J, Commean Paul K, Johnson Jeffrey E
Washington University School of Medicine, 4444 Forest Park Blvd. Room 1101, Campus Box 8502, St. Louis, MO 63108, USA.
Foot Ankle Int. 2007 Jan;28(1):84-8. doi: 10.3113/FAI.2007.0015.
Standard prevention and treatment strategies to decrease peak plantar pressure include a total contact insert with a metatarsal pad, but no clear guidelines exist to determine optimal placement of the pad with respect to the metatarsal head. The purpose of this study was to determine the effect of metatarsal pad location on peak plantar pressure in subjects with diabetes mellitus and peripheral neuropathy.
Twenty subjects with diabetes mellitus, peripheral neuropathy, and a history of forefoot plantar ulcers were studied (12 men and eight women, mean age=57+/-9 years). CT determined the position of the metatarsal pad relative to metatarsal head and peak plantar pressures were measured on subjects in three footwear conditions: extra-depth shoes and a 1) total contact insert, 2) total contact insert and a proximal metatarsal pad, and 3) total contact insert and a distal metatarsal pad. The change in peak plantar pressure between shoe conditions was plotted and compared to metatarsal pad position relative to the second metatarsal head.
Compared to the total contact insert, all metatarsal pad placements between 6.1 mm to 10.6 mm proximal to the metatarsal head line resulted in a pressure reduction (average reduction=32+/-16%). Metatarsal pad placements between 1.8 mm distal and 6.1 mm proximal and between 10.6 mm proximal and 16.8 mm proximal to the metatarsal head line resulted in variable peak plantar pressure reduction (average reduction=16+/-21%). Peak plantar pressure increased when the metatarsal pad was located more than 1.8 mm distal to the metatarsal head line.
Consistent peak plantar pressure reduction occurred when the metatarsal pad in this study was located between 6 to 11 mm proximal to the metatarsal head line. Pressure reduction lessened as the metatarsal pad moved outside of this range and actually increased if the pad was located too distal of this range. Computational models are needed to help predict optimal location of metatarsal pad with a variety of sizes, shapes, and material properties.
降低足底峰值压力的标准预防和治疗策略包括使用带有跖骨垫的全接触鞋垫，但对于确定鞋垫相对于跖骨头的最佳放置位置尚无明确指南。本研究的目的是确定跖骨垫位置对糖尿病和周围神经病变患者足底峰值压力的影响。
对20名患有糖尿病、周围神经病变且有前足足底溃疡病史的受试者进行了研究（12名男性和8名女性，平均年龄=57±9岁）。CT确定了跖骨垫相对于跖骨头的位置，并在三种鞋类条件下测量了受试者的足底峰值压力：深度加大的鞋子以及1）全接触鞋垫，2）全接触鞋垫加近端跖骨垫，3）全接触鞋垫加远端跖骨垫。绘制了不同鞋类条件下足底峰值压力的变化，并与跖骨垫相对于第二跖骨头的位置进行了比较。
与全接触鞋垫相比，在距跖骨头线近端6.1毫米至10.6毫米之间的所有跖骨垫放置均导致压力降低（平均降低=32±16%）。在距跖骨头线远端1.8毫米至近端6.1毫米之间以及近端10.6毫米至近端16.8毫米之间的跖骨垫放置导致足底峰值压力降低程度不一（平均降低=16±21%）。当跖骨垫位于距跖骨头线远端超过1.8毫米时，足底峰值压力增加。
在本研究中，当跖骨垫位于距跖骨头线近端6至11毫米之间时，足底峰值压力持续降低。随着跖骨垫移出该范围，压力降低程度减小，如果垫子位于该范围太远端，则压力实际上会增加。需要计算模型来帮助预测不同尺寸、形状和材料特性的跖骨垫的最佳位置。
