Procedures are non-surgical and performed before surgery as the final step in conservative therapy.
Spinal Cord Stimulator Trial
This procedure has been around for many years. By implanting an electrode in the lower thoracic spinal cord area pain signals coming below that area is interfered with and patient gets significant relief of the intractable leg pain and at times low back pain that they have experienced chronically. This is the last resort surgery and all other options such as physical therapy, medications, and lumbar spine surgery should have been tried and have been unsuccessful in relieving patient's symptoms. If there is surgically treatable pathology such as spinal stenosis or herniated disc or compression fractures this procedure will not work. Also leg pains are in general more responsive to the treatment as opposed to mostly low back pains.
Trial stimulation is 1st tried using electrodes inserted via a needle under sedation. Trial stimulation procedure usually lasts less than one hour. Patients are sent home a few hours after the procedure. Patients are then sent home for a week with the wire connected to spinal cord stimulation generator. If excellent pain relief of greater than 80% of patient's pain is achieved then they are brought back for implantation of the permanent electrode and permanent generator. The permanent electrode is inserted via thoracic laminectomy under heavy IV sedation. The electrode is typically inserted at T7 to T9 levels. Patient is shortly awakened during the procedure so that they can tell whether the permanent paddle electrode is covering their typical area of the pain. If so the permanent electrode is sutured down to the bone so that it will not move and also the permanent generator is inserted typically in the buttock area just below the belt line. The permanent spinal cord stimulator surgery usually lasts one hour.
The complications of the permanent spinal cord stimulator insertion includes very small risk of neurological injury, very small risk of infection, and risk of electrode migration leading to loss of adequate pain control coverage that was achieved during the surgery. The procedure is in general very well tolerated and patient is sent home after overnight stay.
This procedure is performed to relieve pain in those patients who have compression fractures. Other means of conservative care such as medications and bracing and activity modification are recommended. If they fail then this procedure is indicated. MRI scan on STIR image shows "white" signal showing boney edema indicating that fracture is most likely relatively recent and cause of the pain. At times bone scan is also used in addition to confirm the fact that the fractured vertebra is new rather than old. Old healed compression fractures would not cause pain.
The procedure is done under general anesthesia. Two C arms or X ray machines are used. Large needles are inserted into the vertebral bodies using x ray control through the bony structure called pedicles. Then deflated balloon is inserted into the collapsed vertebral body. The balloon is then inflated restoring some height of the collapsed vertebra and making room for cement to be injected later. The balloon is then deflated and cement is injected into the cavity created by balloon deflation under LOW PRESSURE. This low pressure injection into the cavity that is already there makes this procedure much safer than vertebroplasty as far as leakage of cement into undesirable locations such as nerve roots or spinal cord. Leakage of cement onto neural structures can cause paralysis or permanent nerve damage.
The procedure takes about half an hour. The pain relief is usually immediate and thought to be related to the destruction of nerve endings in the fractured bone by heat generated by cement as it sets and also related to the structural stability provided by the cement.
Risks of the procedure include paralysis, nerve injury, wound infection, allergic reactions, and risk of general anesthesia.
Only patients who are in severe pain and cannot cope with conservative measures such as pain medications, bracing, and activity modifications should undergo this procedure.
A nonsurgical method for repairing osteoporosis back fractures, such as vertebral compression fractures. Vertebroplasty is performed by a radiologist, without surgery, and involves inserting a glue-like material into the center of the collapsed spinal vertebra to stabilize and strengthen the crushed bone. The material is inserted through anesthetized skin with a needle and syringe, entering the midportion of the vertebra under the guidance of specialized X-ray equipment. Once inserted, the material hardens to form a cast-like structure within the broken bone. Relief of pain comes quickly from this casting effect, and the newly hardened vertebra is then protected from further collapse. In addition to prompt pain relief, another advantage of vertebroplasty is improved mobility. Also referred to as kyphoplasty.
Radiofrequency ablation is a minimally invasive procedure that is usually performed with local anesthetic and mild sedation.
As with many spinal injections, radiofrequency neurotomy is best performed under fluoroscopy (live x-ray) for guidance in properly targeting and placing the needle (and for avoiding nerve or other injury).
Radiofrequency Ablation Steps
The neurotomy or ablation procedure includes the following steps:
- An intravenous (IV) line is often started so that relaxation medicine (sedation) can be given.
- The patient lies on a procedure table and the skin over the neck, mid-back, or low back is well cleaned.
- The physician numbs a small area of skin with numbing medicine (anesthetic), which may sting for a few seconds.
- The physician uses x-ray guidance (fluoroscopy) to direct a special (radiofrequency) needle alongside the medial or lateral branch nerves.
- A small amount of electrical current is often carefully passed through the needle to assure it is next to the target nerve and a safe distance from other nerves. This current should briefly recreate the usual pain and cause a muscle twitch in the neck or back.
- The targeted nerves will then be numbed to minimize pain while the lesion is being created.
- The radiofrequency waves are introduced to heat the tip of the needle and a heat lesion is created on the nerve to disrupt the nerve's ability to send pain signals.
- This process will be repeated for additional nerves.
Radiofrequency facet block for Chronic Low Back Pain
This procedure is performed for treatment of chronic low back pain that has not responded to conservative measures such as prolonged physical therapy and activity modifications. A trial injection called facet nerve injection is performed 1st at another setting. Facet nerve injection anesthetizes those points between the junction of transverse process and the pedicle where tiny nerves that are known cause of low back pain reside.
If patient receives excellent response to the facet nerve injection then the more permanent radiofrequency facet block is performed. The procedure is performed with patient awake using x ray control called fluoroscopy. Stimulation is performed prior to actual coagulation and this makes the procedure quite safe in terms of nerve injury even though this can still occur. Nerve injury is quite rare. The tip of the radiofrequency needle gets hot coagulating or denaturing the tiny nerve fibers that are the known causes of chronic low back pain. Sometimes the tiny nerve fibers grow back causing recurrent low back pain and some patients require yearly facet blocks if they receive excellent response after each one. Other risks of the procedure includes infection and allergic reactions to medications used.
The overall clinical success rate of the procedure is about 50% in those who has excellent response to trial local anesthetic injection. The procedure takes approximately half an hour and patients are not allowed to drive home so that they need to bring a driver.
Mild analgesics are prescribed such as Vicodin for a few days afterwards as they will be in some pain from the procedure itself. Return to work without any restriction is possible usually in a few days after the procedure. Whether the procedure is successful or not is not determined until about a few weeks after the procedure when the pain from the procedure itself goes away.
This procedure has been around for at least 25 years. Similar procedure is performed in the cervical spine for control of chronic neck pain.