Implantable fixation devices for rejoining opposed portions of a separated bone. The devices include plates that may be affixed to a rib and realign separated portions of the rib or other body part. The devices may also include various locking mechanisms that receive a cable that may be used to realign and bring together separated portions of a bone or other body part. The devices may further include plates that may be affixed to a sternum and realign separated portions of the sternum or other body part.