The incontinence pads that I've bought are like a pair of knickers not just pads. They have the "pad" from the top front to top back and the sides are elastic and material and you don't have to wear knickers with them. The one's I've got are Depend full brief type. You can get one's that have the pad from front to back and are held by two pieces of elastic (not for me). Apparantely they are really good because they are so long, cover and hold so much that you don't have leakage front, back or sides between our legs.
They are in the same section as the normal pads so have a look next time you're shopping. They are more expensive than a pack of pads but you don't have to worry about staining your knickers.