To determine the optimum position of a metatarsal (MT) pad to treat metatarsalgia. We used a sensing mat with 16 x 16 sensors, 4.4 x 4.4 mm each, to measure plantar pressure in ten metatarsalgia patients walking with an MT pad in various positions. Peak pressures of the MT head and MT pad were analyzed. Walking without MT pads, the peak pressure of the MT head was 678 +/- 227 and 687 +/- 228 kPa in one proximal and one distal row of three sensors. Placement of the MT pad resulting in peak pressure two sensors proximal to the peak pressure of the MT head did not significantly reduce peak pressure on the MT head. In contrast, placement of the MT pad resulting in peak pressure just proximal to the peak pressures of the MT head reduced the proximal and distal peak pressures on the MT head to 427 +/- 97 and 431 +/- 92 kPa (P < 0.05). Optimum pressure reduction on the MT head is attained when the peak pressure generated by the MT pad is just proximal to the MT head.