Back and Neck Injections
CT guided injections are an extremely safe and modern procedure. These injections are typically considered when physiotherapy and oral medication have been tried, but the pain is still not tolerable. CT guided injections are often considered before surgery is contemplated or if surgery is declined or not possible. These injections deliver powerful medications directly to the area that that is the source of the pain, and thus are usually much more effective than tablets.
In most cases of back pain, CT guided injections may be used both, to find out what is causing your pain and to treat your pain. If an injection into an area provides pain relief, it is likely that the particular area injected is the source of pain – thus the cause of the problem has been diagnosed. Injections are also therapeutic in that they can provide relief from pain.
Medications
With most spinal injections a mixture of medications is injected. Local anaesthetic (numbing or freezing medication) is mixed with cortisone (a naturally occurring strong anti-inflammatory). This combination of drugs is injected into a specific area of the spine. The anaesthetic is a fast-acting drug, which will start working before you leave our practice. Thus, we will know if the area we have injected is the source of the pain. The local anaesthetic only lasts a few hours (up to 8 hours). Cortisone is long lasting and may not begin working for several days following the injection, but the effects can last for months.
TYPES OF INJECTIONS
Epidural Injection
An epidural injection is a common type of injection that is given to provide relief from certain types of back and neck pain, caused by a narrow spinal canal. The "epidural space" is the space around the spinal sac, just inside of the bony spinal canal. This space runs the entire length of your spine and thus injections here can treat multiple levels.
Perineural Injection
Perineural injections deliver the medication around the affected nerve. As the spinal nerves leave the spinal cord, they exit the spine sideways. It is at this exit that these nerves are most likely compressed, impinged or "pinched" by either a bulging disc or bone spurs. This pressure on the spinal nerves causes inflammation and pain. The pain could effect the back alone or can radiate to the legs, which is known as sciatica.
Facet Joint Injection
Facet joint injections are used to localize and treat low back pain caused by problems of the facet joints. These joints are located on each side of the vertebrae. They join the vertebrae together and allow the spine to move back and forth. Facet joints cause pain from inflammation that occurs in the joint from arthritis and joint degeneration.
IMPORTANT ADDITIONAL INFORMATION
Bleeding Tendencies
If you have a tendency to heavy bleeding or take anti-coagulant therapy (medication that prevents blood clotting), you may not be a good candidate for spinal injections. Make sure your doctor has a list of your medications well ahead of your scheduled procedure.
Infections
If you have a local skin or systemic infection, a spinal injection may put you at greater risk for spreading the infection into the spine. Make sure to tell your doctor if you have any infected wounds, boils, or rashes anywhere on your body.
Other Medical Conditions
Injections are usually an elective procedure offered to patients without life-threatening conditions. A medically unstable patient should have his or her medical condition treated before any elective injections are given.
If you have an accompanying medical illness, you should discuss the risks of spinal injections with your physician. For instance, patients with diabetes might experience an increase in blood sugar after an injection with cortisone. Patients with congestive heart failure, renal failure, hypertension, or a significant cardiac disease may have problems due to the effects of fluid retention several days after an injection.
OTHER INFORMATION
The number of and frequency of injections is debated, although it is generally considered reasonable to limit the number to three times per year to avoid systemic side effects of the steroids. Side effects are minimal and consist mainly of mild tenderness in the area of injection which disappears in 1-2 days. This treatment, along with analgesics and physical therapy has brought relief to thousands of patients, avoiding, in the majority of cases, the need for surgery.
How is it done?
The patient lies on the CT table. A quick low dose planning CT scan is performed. The patient is given a skin injection of local anaesthetic (freezing or numbing). The radiologist (doctor) then introduces a needle under CT guidance into the area that is considered the source of the pain. Medication is then injected into the area. The medications include an anaesthetic and steroid. The whole procedure usually takes about 5 minutes and is generally extremely well tolerated.
What happens after the procedure?
Patients are then asked to record the relief they experience and keep a record of their pain relief during the next week on a post injection evaluation sheet. This will be given to the patient when they are discharged home. A follow-up appointment will be made for a repeat injection if necessary. The back or legs may feel weak or numb for a few hours, thus, it is best to have someone drive you home. No driving is allowed the day of the procedure. Patients may return to their normal activities the day after the procedure, including returning to work.
Most patients will experience pain relief immediately after the procedure because of the anaesthetic. The anaesthetic will usually wear off within 8 hours, thus, the pain often returns the evening of the procedure. The cortisone usually takes at least 2 days to begin working. It is best to ease back into normal activities over 1 to 2 weeks as the medication begins to work. Bed rest is not necessary.
General Instructions
Patients can eat a light meal within a few hours before the procedure. If a patient is an insulin dependent diabetic, they must not change their normal eating pattern prior to the procedure.
Patients should confirm with their local doctor that they can take all their routine medications. (i.e. high blood pressure and diabetic medications).
Patients should not take pain medications or anti-inflammatory medications the day of their procedure.
A driver must accompany the patient and be responsible for getting them home.
Success rates
CT guided injections are generally successful in relieving pain for most patients. While the effects of the injection tend to be temporary (one month to one year), injections can be very beneficial in providing relief for patients during an episode of severe back pain and allows patients to progress in their rehabilitation.
