Spinal Cord Stimulation

Overview:

Spinal cord stimulation uses low voltage stimulation of the spinal cord to block the signal of chronic pain. It helps you to better manage your pain, improve your level of activity, and potentially decrease the amount of pain medication. It may be an option if you have long-term (chronic) pain of the trunk or extremities and have not found relief through traditional methods. A small battery-powered generator implanted in the body transmits an electrical current to your spinal cord.

 

What is a spinal cord stimulator:

A spinal cord stimulator (SCS) is a device surgically placed under your skin to send a mild electric current to your spinal cord. A small wire carries the current from a pulse generator to the nerve fibers of the spinal cord.  Your pain is reduced because the electrical current interrupts the pain signal from reaching your brain. 

Before a spinal cord stimulator is implanted a patient undergoes a trial of stimulation. This allows the patient to experience the treatment and to gauge the amount of pain relief they can expect if they undergo implantation.  The goal for spinal cord stimulation is a 50-70% reduction in pain. Stimulation does not work for everyone. If unsuccessful, the implant can be removed.

 

A SCS system consists of:

·    An implantable pulse generator with battery that creates electrical pulses.

·    Lead(s) with a number of electrodes (8-16) that delivers electrical pulses to the spinal cord.

·    A hand-held remote control that turns the pulse generator on and off and adjusts the strength of the current.

The pulse generator is programmable and various settings can be used to control various pain pathways.

 

Who is a candidate:

You may be a candidate for SCS if you meet the following criteria:

·    Conservative therapies have failed

·    Your source of pain has been verified

·    You would not benefit from additional surgery

·    You have undergone a psychological screening to be sure you are of sound mind and understand the implications of having a spinal cord stimulator implanted.

·    You have no medical conditions that would keep you from undergoing implantation

·    You have had a successful trial stimulation

An SCS can help lessen chronic pain caused by:

·    Chronic leg (sciatica) or arm pain: ongoing, persistent pain caused by degenerative conditions like arthritis or spinal stenosis, or from nerve damage.

·    Failed back surgery syndrome: failure of one or more surgeries to control persistent leg or arm pain.

·    Complex regional pain syndrome (CRPS): a progressive disease of the nervous system in which patients feel constant chronic burning pain, typically in the foot or the hand. Formerly called reflex sympathetic dystrophy (RSD).

·    Arachnoiditis: painful inflammation and scarring of the meninges (protective layers) of the spinal nerves.

Peripheral neuropathy

·    Other: stump pain, angina, peripheral vascular disease, multiple sclerosis, spinal cord injury or peripheral neuropathy.

 

The Process:

Determining whether a spinal cord stimulator will be a good pain management option for you is a complex process. Before a permanent stimulator can be implanted, you must undergo a trial to see if the device decreases your level of pain.

The surgery is performed on an outpatient basis in two stages: Stage 1 is a trial stimulation and Stage 2 is implantation of the permanent device.

 

Stage 1. Spinal Cord Stimulation Trial

Trial stimulation is very important to determine if the procedure will be successful. It will tell if stimulation is correct for the type, location, and severity of your pain. It will also evaluate the effectiveness of various stimulation settings.

The insertion of a trial lead is typically performed with IV sedation. A hollow needle is inserted through the skin (percutaneous) into the epidural space using fluoroscopy (video X-ray). The lead(s) are then fed through the needle until they are in the proper position. When proper position of the lead(s) is confirmed, they are then attached to an external generator which is taped to the skin.

After the trial procedure, you will be sent home with instructions on how to use the trial stimulator and care for your incision site. Keep a written log of the stimulation settings during different activities and the level of pain relief. After 5 to 7 days, you will return to the doctor's office to remove the trial leads and discuss permanently implanting the stimulator.

 

Stage 2. Permanent implantation of the Spinal Cord Stimulator

If the trial is successful and you experienced greater than 50% improvement in pain, you can be scheduled for surgery to implant the permanent stimulator. There is a 3 to 6 week lag time between the trial and permanent implant to allow for the test area to heal and to get on the surgical schedule.

 

What happens before surgery?

You may be scheduled for pre-surgical tests (e.g., blood test, electrocardiogram, chest X-ray) several days before surgery. In the doctor's office, you will sign a consent form permitting the surgeon to perform the procedure as well as completing other forms so that the surgeon knows your medical history (allergies, medicines/vitamins, bleeding history, anesthesia reactions, previous surgeries). Discuss all medications (prescription, over-the-counter, and herbal supplements) you are taking with your health care provider as some medications need to be continued or stopped the day of surgery.

Stop taking all non-steroidal anti-inflammatory medicines (Naprosyn, Advil, Motrin, Nuprin, Aleve, etc.) and blood thinners (Coumadin, Plavix, etc.) 1 to 2 weeks before surgery as directed by your doctor. Do not take Ginsing, Garlic or Gingko at least 2 weeks before your surgery. No food or drink is permitted past midnight the night before surgery.

Depending on your risk factors your doctor may prescribe an antibiotic ointment to use in your nostrils for 7 days before surgery and antibiotic pills to take after your surgery.

 

Morning of surgery

·    Shower using antibacterial soap. Dress in freshly washed, loose-fitting clothing.

·    Wear flat-heeled shoes with closed backs.

·    If you have instructions to take regular medication the morning of surgery, do so with small sips of water.

·    Remove make-up, hairpins, contacts, body piercings, nail polish, etc.

·    Leave all valuables and jewelry at home (including wedding bands).

·    Bring a list of medications (prescriptions, over-the-counter, and herbal supplements) with dosages and the times of day usually taken.

·    Bring a list of allergies to medication or foods.

Arrive at the surgery center 1 hour before your scheduled surgery time to complete the necessary paperwork and pre-procedure workups. An anesthesiologist will talk with you and explain the effects of anesthesia and its risks. As part of your pre-surgical workup, an intravenous (IV) line will be placed in your arm.

 

What happens during surgery:

There are two parts to the procedure: placement of the lead in the epidural space of the spinal cord and placement of the pulse generator in the buttock or abdomen. There are six main steps of the procedure, which generally take 1 to 2 hours.

 

Step 1. Prepare the patient

You are placed on your stomach on the operative table. The team will work with you to make sure you are comfortable before you are given sedation (similar to the medications given during a colonoscopy). Next, the areas of your back are prepped where the leads and the generator are to be placed. Local anesthetic will be injected where incisions are to be made to prevent pain during the procedure.

 

Step 2. Place the leads

Placement of the surgical leads is performed with the aid of fluoroscopy (a type of X-ray). A small skin incision is made in the middle of your back. A hollow needle is directed, under fluoroscopic guidance, into the epidural space. The leads are placed in the epidural and secured with sutures.

 

Step 3. Test stimulation

In some cases, you will be awakened so that you can help the doctor determine how well the stimulation covers your pain pattern without feeling any pain or discomfort from the lead implantation itself. Several stimulation settings will be tried, and the surgeon will ask you to describe the location of any tingling you feel. These settings will be used to program the pulse generator at the end of surgery, so your feedback during this part of the surgery is important for providing you the best pain relief.

 

Step 4. Place the pulse generator

A 4 to 6 centimeter skin incision is made in the flank or buttocks. The surgeon creates a pocket for the generator between the skin and muscle layers. The extension wire is attached to the pulse generator. The generator is then correctly positioned under the skin and sutured to the thick fascia layer overlying the muscles.

 

 Step 5. Tunnel the extension wire

Once the leads are in place and the generator pocket has been made, the lead is passed under the skin from the spine to your flank or buttock where the generator will be implanted.

 

Step 6. Close the incisions

The two incisions are closed with sutures or staples and a dressing is applied.

 

What happens after surgery:

You will wake up in the postoperative recovery area. Your blood pressure, heart rate, and respiration will be monitored, and your pain will be addressed. You will be discharged home the same day. The pulse generator will be programmed before you leave. Often you are too sleepy from the anesthesia to get accurate programming, so adjustments to your program will be performed frequently by the SCS representative. You will be given written instructions to follow when you go home.

 

Discharge instructions

Discomfort

·    Pain after this type of surgery is typically minimal but you may require opioid medications for a short period of time. You are to continue your regular pain medications as prescribed. Opioid medications may cause constipation, so drink lots of water and eat high fiber foods. If needed, laxatives (e.g., Dulcolax, Senokot, Milk of Magnesia) may be bought without a prescription.

·    Spinal headaches are caused by leakage or loss of cerebrospinal fluid around the catheter or lead site. This is rare but if it does happen lie flat and drink plenty of caffeinated fluids.

Restrictions

·   In order to improve healing and prevent lead movement follow these instructions for 6 weeks:

- do not bend, twist, stretch, or lift objects over 10 pounds

- do not raise arms above your head

- do not climb too many stairs or sit in one position for long periods of time

·    Do not drive until discussed with your surgeon.

·    Housework and yardwork are not permitted until after the first follow-up office visit. This includes gardening, mowing, vacuuming, ironing, and loading/unloading the dishwasher, washer, or dryer.

·    Postpone sexual activity until your follow-up appointment unless your surgeon specifies otherwise.

·    Gradually return to your normal activities. Walking is encouraged; start with a short distance during the first two weeks and then gradually increase to 1 to 2 miles daily.

·    A physical therapy program may be recommended.

Bathing/Incision Care

·    You may shower as directed by your surgeon. For the SCS Trial, we do not want you to shower until the leads are removed. You may sponge bath until given permission to shower

·    Do not take a tub bath or submerge yourself in water for 4 weeks. Pat your incision dry with a soft towel to avoid irritation.

·    Inspect the incision line twice daily.

·    Fluid may accumulate under the skin around the leads or the device creating a visible swelling. Call the doctor if this occurs.

·    Steri-strips or a thin film (skin glue) may cover the incision. After showering, gently pat dry the steri-strips or film. The steri-strips or film will gradually wear off over one to two weeks. Sutures or staples that remain in place when you go home will need to be removed around 7-10 days after your surgery.

 

When to Call Your Doctor

·    If your temperature exceeds 101° F or if the incision begins to separate or show signs of infection, such as redness, swelling, pain, or drainage.

·    If your headache persists after 48 hours.

·    If you have sudden severe back pain, sudden onset of leg weakness and spasm, loss of bladder and/or bowel function - this is an emergency - go to a hospital and call your surgeon.

 

What are the risks:

No surgery is without risks. General complications of any surgery include bleeding, infection, blood clots, and reactions to anesthesia. Specific complications related to SCS may include:

·    Undesirable changes in stimulation (can possibly be related to cellular changes in tissue around electrodes, changes in electrode position, loose electrical connections, and/or lead failure)

·    Epidural hemorrhage, hematoma, infection, spinal cord compression, and/or paralysis (can be caused by placing a lead in the epidural space during a surgical procedure)

·    Unpleasant sensations or motor disturbances, including movement (can be caused by stimulation at high outputs; and, if unpleasant sensations occur, turn off the neurostimulator)

·    Battery failure and/or battery leakage

·    Chest wall stimulation

·    Cerebrospinal fluid leak

·    Persistent pain at the electrode or stimulator site

·    Seroma at the implant site

·    Lead migration, which can result in changes in stimulation and reduction in pain relief

·    Allergic or rejection response to implant materials

·    Generator migration and/or local skin erosion

·    Paralysis, weakness, clumsiness, numbness, or pain below the level of implantation

Conditions for which you might need additional surgery include movement of the lead, breakage of the lead, or mechanical failure of the device. All of these are rare. Reasons for removal of the device include infection and failure to relieve pain.

 

Living with a stimulator:

Once the SCS has been programmed, you are sent home with instructions for regulating the stimulation by controlling the strength and the duration of each stimulation period. Your doctor may alter the pulse width, amplitude, and frequencies on follow-up visits if necessary.

The handheld programmer lets you turn the stimulator on and off, select programs, and adjust the strength of the stimulation. Most people are given multiple programs to achieve the best possible pain relief during specific activities. You can use your spinal cord stimulator around the clock if necessary.

Be sure to carry your Implanted Device Identification card when flying, since the device is detected at airport security gates. You should turn off your system before passing through security gates.

Before undergoing any medical or dental procedure and before undergoing physical therapy, chiropractic care or massage therapy let your provider know you have a spinal cord stimulator.