Abstract:
A device circles the spinal segmental nerves like a ring and cause stimulation of the nerves. The present invention offers magnetic as well as electric stimulation properties in order to balance the two modes.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention is directed to rehabilitation of patients with spinal trauma and stroke and more particularly to such rehabilitation using stimulation rings. 
       DESCRIPTION OF RELATED ART 
       [0002]    Spinal cord trauma is damage to the spinal cord. It may result from direct injury to the cord itself or indirectly from disease of the surrounding bones, tissues, or blood vessels. 
         [0003]    Injuries at any level can cause increased muscle tone (spasticity), loss of normal bowel and bladder control (may include constipation, incontinence, bladder spasms), numbness, sensory changes, pain, weakness, and paralysis. When spinal cord injuries occur in the neck area, symptoms can affect the arms, legs, and middle of the body. The symptoms may occur on one or both sides of the body. Symptoms can also include breathing difficulties from paralysis of the breathing muscles, if the injury is high up in the neck. When spinal injuries occur at chest level, symptoms can affect the legs. Injuries to the cervical or high thoracic spinal cord may also result in blood pressure problems, abnormal sweating, and trouble maintaining normal body temperature. When spinal injuries occur at the lower back level, symptoms can affect one or both legs, as well as the muscles that control the bowels and bladder. 
         [0004]    Forms of treatment vary. Corticosteroids, such as dexamethasone or methylprednisolone, are used to reduce swelling that may damage the spinal cord. If spinal cord pressure is caused by a growth that can be removed or reduced before the spinal nerves are completely destroyed, paralysis may improve. Ideally, corticosteroids should begin as soon as possible after the injury. 
         [0005]    Surgery may be needed to remove fluid or tissue that presses on the spinal cord (decompression laminectomy); remove bone fragments, disk fragments, or foreign objects; or fuse broken spinal bones or place spinal braces. 
         [0006]    Bedrest may be needed to allow the bones of the spine to heal. 
         [0007]    Spinal traction may be recommended. That can help keep the spine from moving. The skull may be held in place with tongs (metal braces placed in the skull and attached to traction weights or to a harness on the body). The patient may need to wear the spine braces for a long time. 
         [0008]    The patient may need physical therapy, occupational therapy, and other rehabilitation therapies after the injury has healed. Rehabilitation will help the patient to cope with the disability from the spinal cord injury. 
         [0009]    Muscle spasticity can be relieved with medications taken by mouth or injected into the spinal canal. Botox injections into the muscles may also be helpful. Painkillers (analgesics), muscle relaxers, and physical therapy are used to help control pain. 
         [0010]    However, none of those treatments encourage regrowth of nerve tissue. One form of treatment that is intended to do so is magnetic nerve stimulation. Available magnetic nerve stimulation devices for stimulating sacral nerve roots are indirect. Indirect magnetic stimulation of spinal segments and sacral nerve roots has been shown to promote bowel emptying of patients with spinal cord damage as well as induce enhancement of respiratory function in tetrapegic patients. However, indirect magnetic nerve stimulation has received mixed results, possibly due to its indirectness. There are no existing devices for direct magnetic spinal nerve stimulation. 
       SUMMARY OF THE INVENTION 
       [0011]    It is therefore an object of the invention to provide direct magnetic spinal nerve stimulation. 
         [0012]    To achieve the above and other objects, the present invention is directed to a device that circles the spinal segmental nerves like a ring and causes stimulation of the nerves. Electric stimulation of the severed nerve roots has given favorable results. Some reports indicate that magnetic stimulation reduces spasticity. The present invention offers magnetic as well as electric stimulation properties in order to balance the two modes. 
         [0013]    The present invention can be utilized for direct stimulation of patients with spinal trauma and stroke. The idea is to simulate anterior roots of the spinal cord segmental nerves related to the movements. Initially, the targeted functions will be bowel emptying, bladder stimulation, and cough induction. If those become successful, a program and a stimulator will be made for all motor functions based on the root involvement of those of limb movements. 
         [0014]    The final product will allow a patient to control his/her motor movements using a remote control device. The initial mode of stimulation will be magnetic. If the outcome following magnetic stimulation is reduction of hyperfexia or spasticity, which is a common side effect following upper motor neuron lesions like spinal cord injury or stroke, magnetic stimulation will only be insufficient to achieve the full motor control. In that case, electronic stimulation through wire electrodes along with magnetic stimulation will be applied. A balance of those two modes of stimulation will control hyper reflexia and spasticity to and achieve movements. 
         [0015]    A wireless power supply and telemetric control can be provided to avoid infections and minimize the size of the device. Those devices will be implanted microsurgically and will be screwed to the bone using plastic screws. 
         [0016]    Stimulating coils can be made out of plastic magnetic conductance material. That approach will allow patients to go through the usual MRI scans, etc. 
         [0017]    Immediate applications include the following:
       1) Stimulate bowel movements;   2) Stimulate bladder emptying;   3) Stimulate an erection;   4) Reduce muscle spasticity following upper motor neuron lesions; and   5) Induce cough to prevent respiratory infections.       
 
         [0023]    In some possible embodiments, all spinal cord segments will carry rings for individual nerve stimulation, and a software program will stimulate all involved segments in optimum stimulation for motor movement, with the goal of immediate motor control following peripheral nerve lesions. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0024]    A preferred embodiment and variations thereof will be set forth with reference to the drawings, in which: 
           [0025]      FIG. 1  is a diagram showing the placement of the collar of the preferred embodiment in the patient&#39;s nervous system; 
           [0026]      FIG. 2  is a diagram showing the placement of the collar relative to the spine; 
           [0027]      FIG. 3A  is a close-up view of the sleeve on a nerve; 
           [0028]      FIG. 3B  is a cross-sectional view of the collar; and 
           [0029]      FIG. 4  is a diagram showing an alternative placement of the collar. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0030]    A preferred embodiment of the present invention and variations thereof will be set forth in detail with reference to the drawings, in which like reference numerals refer to like elements or steps throughout. 
         [0031]      FIG. 1  shows an example of placement of a spinal stimulating collar or ring  100 . The spinal cord  102  (shown here in cross section) includes a dorsal (posterior) horn  104  of spinal gray matter; a lateral horn  106 , found only in segments T 1 -L 2 , of preganglionic sympathetic neurons; and a ventral (anterior) horn  108  containing motor neurons. Dorsal and ventral roots  110 ,  112  extend from the dorsal and ventral horns  104 ,  108  respectively. The dorsal root includes a dorsal ganglion  114 . The roots  110 ,  112  join to form a spinal nerve  116 , which branches into a dorsal primary ramus  118 , which goes to the skin and muscles of the back, and a ventral primary ramus  120 , which splits into sensory fibers  122 , postganglionic sympathetic innervation (into glands and blood vessels)  124 , and motor axons  126  to skeletal muscle. The ventral primary ramus  120  is also connected via a gray ramus communicans  128  and a white ramus communicans  130  to a sympathetic (paravertebral) ganglion  132 . 
         [0032]    The collars  100  surround the ventral nerve roots  112  and are attached to the bone by microscrews or in any other suitable manner.  FIG. 2  shows the spine  200  defining the spinal canal  202 . The posteriors of the vertebral bodies and the vertebral arches form the bony border of the spinal canal  202 . The spinal canal  202  contains the spinal cord  102  and the nerve roots  110 ,  112 . A spinal stimulating collar  100  is attached as shown. 
         [0033]      FIG. 3A  shows a collar  100  surrounding a ventral root  112 .  FIG. 3B  shows a coronal section of the collar  100 , including stimulating magnetic fibers  302 . 
         [0034]      FIG. 4  shows the use of the preferred embodiment to surround nerve roots during peripheral nerve repair. An implanted stimulator  400  includes a transmitting coil  402  for control and is conne4cted via electrode leads  404  to collars or rings  100 . The coil  402  allows wireless communication with a processor  406  for control. Such a stimulator  400  and processor  406  can be used in any embodiment to provide the correct stimulation. 
         [0035]    While a preferred embodiments and variations thereof have been set forth in detail, those skilled in the art who have reviewed the present disclosure will readily appreciate that other embodiments can be realized within the scope of the invention. For example, recitations of materials and of the placement of the collar are illustrative rather than limiting. Therefore, the present invention should be construed as limited only by the appended claims.