Systems for bone and spinal stabilization, fixation and repair include intramedullar nails, intervertebral cages and prostheses, remotely activatable prostheses, tissue extraction devices, and electrocautery probes. The intramedullar nails, intervertebral cages and prostheses, are designed for expansion from a small diameter for insertion into place to a larger diameter which stabilizes, fixates or repairs the bone, and further can be inserted percutaneously. Remotely activatable prostheses can be activated from an external unit to expand and treat prosthesis loosening. Tissue extraction devices, and electrocautery probes are used to remove tissue from desired areas.