Total metatarsophalangeal joint prosthesis, one-piece. A sterile implantable device designed to replace the metatarsophalangeal (MTP) joint(s) of the foot (toe). The device is made of a single piece of silicone elastomer. It is is intended to treat degenerative or traumatic arthritis, hallux valgus, hallus rigidus, and/or an unstable or painful MTP joint.