An electrode for the stimulation of the sciatic nerve is disclosed, the electrode being comprised of a pair of physiologically inert plastic strips each of which has a plurality of contact means fixed thereto. The contact or electrode means which preferably are formed of platinum comprise a plurality of buttons positioned on opposite sides the sciatic nerve and are oriented by the surgeon with respect to each other to achieve optimum pain inhibition. When properly placed, the two plastic members are suitably secured to each other. External power means that are electrically coupled to the contact buttons by conductive leads provide selective stimulation of the sciatic nerve in order to relieve pain. The conductive leads for the contact buttons that are not coupled to the source of electrical power are severed. The aforementioned abstract is neither intended to define the invention of the application which, of course, is measured by the claims, nor is it intended to be limiting as to the scope of the invention in any way.
A spinal electrode for use in spinal cord stimulation having portions which are specifically provided for coupling the electrode to the adjacent spinal tissue so that displacement of the electrode cannot easily occur by normal bodily motion as is a failure mechanism of prior electrode designs. The distal end of the electrode which includes the electrical contacts also includes at least one laterally extending non-electrical portion. The extending portions are provided for receiving a suture or wire therethrough. The laterally extending portions may include a readily identifiable distinguishing feature, such as a color dye or a textural difference, so that it can be readily seen as a safe region through which a suture may be passed. Alternatively (or in addition), the laterally extending portions may include a through hole so that the tip of the electrode may be tied to the spinous process (or other spinal bone) by a wire.
A flexible and non-conductive, artificial, implantable nerve plate has an module of about 3000-1000 N/mm.sup.2 and a thickness of <50 .mu.m for placement and insertion between the fascicles of a nerve bundle. Multiple electrodes are arranged on the two sides of the nerve plate, which is connected via conducting lines inside the nerve plate to a cable integrated with the nerve plate; and the cable is connectable to a control and signal receiver unit.
Methods, and apparatus are disclosed for stimulation the central, peripheral, and autonomic with particular attention being given to the medial branch (210) of the spinal nerve (212) associated with a painful spinal facet joint so as to block pain impulses from reaching the spinal cord. The preferred apparatus includes a neurostimulator (204), and two or more electrodes (206) which carry electrical pulses to the target nerves. The impulses are intense enough to cause stimulation of a given medial branch (210), and its articular branches, but not so large as to spread to the spinal cord itself. In the preferred embodiment the stimulator (204) is physically small and battery operated facilitating implantation underneath the skin. The stimulator (204) includes a controller (not shown), and appropriate electronics operative to generate electrical impulses tailored to an individual's need for appropriate pain relief in terms of pulse frequency, pulse width, and pulse amplitude. In an alternative embodiment, the stimulator (204) further includes electrodes (206), and electrical circuitry operative to monitor myoelectrical activity generated by the surrounding muscles, and modulate the impulses generated by the stimulator to meet the demands of the individual's activity and/or prolong battery life.
Intractable pain that is transmitted by the spinal cord and sensed by the human body is suppressed by implanting an electrode carrying device near a nerve bundle in the spinal cord. The device is constructed of an electrical insulating substance inert to the body fluids and tissue and carries electrodes for supplying electric current to the spinal cord thereby suppressing the sensed quantity of pain. These electrodes are in aligned, spaced relationship with the alignment extending transversely of the nerve bundle. A switch may be positioned within the body and used to supply the current to certain of the electrodes in response to the quantity of pain sensed thereby controlling same by varying the area of the spinal cord affected.
A device and a method for anatomic implantation to provide electrical interface to nerves. Included in the device are a pair of electrical leads secured to a coupling formed from a piece of woven sheet material, and having ends connected to spaced apart input terminals disposed adjacent to an inner surface of the coupling. Connected to the opposite ends of the leads are output terminals for interfacing to electrical recording or measuring instruments. During implantation, a subject nerve is embraced by the inner surface of the sheet material which is shaped for juxtaposition the outer surface of the nerve at a minimum spacing therefrom of 0.3 millimeters. In the period following implantation the interstices of the sheet material coupling receive anatomic tissue growth establishing a structurally stable dimensional relationship between the nerve and both the input electrodes and the coupling. The fixed input electrode spacing between the electrode and the nerve improves the quality of the electrical signals received from the nerve while the 0.3 millimeter minimum spacing insures that the nerve will continue living for extended periods of time.
