Coded-sequence activation of surgical implants

1. A device for implantation in a body, comprising:

a receiver responsive to a trigger signal;

authentication circuitry coupled to the receiver and operative to distinguish an authentic trigger signal from a non-authentic trigger signal, the authentication circuitry being responsive to an authentic trigger signal to generate an actuation signal;

an actuatable member coupled to receive the actuation signal, the actuatable member being responsive to the actuation signal to change configuration; and

a physiological sensor configured to sense a physiological parameter in the body,

wherein the receiver is configured to accept any one of a plurality of trigger signals, each trigger signal being associated with a respective permissions level, and wherein the authentication circuitry is operative to use the sensed physiological parameter together with the permissions level to distinguish an authentic trigger signal from a non-authentic trigger signal.

2. The device of claim 1 , wherein the authentication circuitry is configured to generate an actuation signal after receiving the trigger signal only if the sensed physiological parameter is indicative of an abnormal condition of the body.

3. The device of claim 2 , wherein the abnormal condition of the body is selected from the group consisting of loss of consciousness, altered consciousness, abnormal heart rhythm, abnormal breathing rhythm, abnormal blood pressure, abnormal blood chemistry, change in tissue perfusion, myocardial infarction, stroke, hypoglycemia, hyperglycemia, electrolyte disturbance, and hormone imbalance.

4. The device of claim 2 , wherein the authentication circuitry is configured to determine that the physiological parameter is indicative of an abnormal condition if the physiological parameter falls outside of a selected normal range.

5. The device of claim 4 , wherein the authentication circuitry is configured to accept a change in the selected normal range.

6. The device of claim 1 , wherein the device is selected from the group consisting of a bone implant, a spinal implant, a tooth implant, a tissue expander, an intralumenal device, a stent, a shunt, a gastrointestinal camera, a drug reservoir, a pacemaker, a defibrillator, a cochlear implant, a brain stimulator, an artificial joint, a gastric band, an artificial sphincter, an orthodontic appliance, a cosmetic implant, a lip augment, a breast augment, a pectoral augment, and a deltoid augment.