Plantar Soft-tissue Augmentation The plantar fat pad, made up of ligaments and fatty tissue at the ball of the foot and heel, protects and cushions the underlying bone, tendons and neurovascular structures of the foot. With any number of traumatic events, including multiple surgical incisions, fractures, aging, or chronic injury, this plantar fat pad can become displaced or decrease in size. This often results in a painful weight bearing surface on the bottom of the foot that can lead to callus or ulceration. Plantar soft-tissue augmentation using GRAFTJACKET® Matrix covers and protects the underlying soft tissues and bone.