As you have experienced, epidural spinal injections (ESIs) can reduce your pain. The steroid used in the injection cortisone is an extremely powerful anti-inflammatory drug.
When injected around an inflamed and swollen nerve, it can reduce the inflammation and swelling, which in turn, reduces pain. Reducing swelling can allow the nerves to function better, which then decreases the numbness and weakness that some patients have with this condition.
The effects of these injections are temporary. The results may last from a couple weeks to a couple months. The idea is to reduce your symptoms so that you can move more easily and begin a physical therapy program with less pain.
They also help the body repair the underlying condition. For example, most disc herniations cause a great deal of pain when they first occur. This is due to the chemicals that leak from the torn disc and inflame the nerves.
Over several weeks to months, the disc heals enough to stop leaking these chemicals. If the cortisone can reduce the symptoms at the beginning, then when the cortisone injection wears off, the chemical irritation may be gone and the pain may not return. The cortisone itself does not heal the disc herniation.
In other conditions, the cortisone injection is repeated 1 to 3 times per year to help control the symptoms. This is usually done when surgery is too risky or you don't want to have surgery. Older adults with spinal stenosis, often choose this option.
Spinal stenosis occurs when the spinal canal where the nerves travel is too tight. This results in inflammation and swelling of the nerves and soft tissues. The swelling makes the spinal canal even tighter. The nerves do not have enough room to function correctly and begin to cause pain, numbness and weakness.
An ESI once every six months may reduce the swelling enough to take the pressure off the nerves. You get relief from the symptoms of pain, numbness and weakness but the narrowed spinal canal doesn't get any bigger from this treatment.
Your surgeon is the best one to advise you on the frequency and safety of this treatment for your particular problem. Your age, general health, and length of time the treatment is effective are just a few of the things considered when deciding how many and how often to use ESIs.