A caudal injection is a medical procedure that involves delivering medication into the caudal epidural space, located at the very bottom of the spine, just above the tailbone. This area is part of the epidural space, which surrounds the spinal cord and its nerve roots. The term “caudal” refers to its position towards the tail end of the body. This minimally invasive injection is performed to address various conditions causing pain in the lower back, buttocks, and legs.
Why Caudal Injections Are Performed
Caudal injections are recommended to alleviate pain stemming from inflammation or irritation of spinal nerves in the lower back. Conditions such as sciatica, which causes pain radiating into the leg due to sciatic nerve irritation, are often treated with this procedure. It also addresses pain from herniated or bulging discs, where spinal discs press on surrounding nerves, and spinal stenosis, a narrowing of the spinal canal that compresses nerves.
The primary goal of a caudal injection is to deliver anti-inflammatory medication, usually a corticosteroid like triamcinolone or methylprednisolone, directly to the affected nerves. This medication works to reduce swelling and inflammation around the nerve roots, thereby easing pain signals. Sometimes, a local anesthetic, such as lidocaine or bupivacaine, is included to provide immediate, temporary pain relief. The injection can also serve as a diagnostic tool, helping healthcare providers pinpoint the exact source of pain.
How a Caudal Injection is Administered
Before the procedure, patients change into a medical gown and lie face-down on an X-ray table, sometimes with a pillow placed under the abdomen for comfort. The medical professional cleans and disinfects the lower back area where the injection will be administered. A local anesthetic is then injected into the skin to numb the site, minimizing discomfort during the deeper injection.
The medical professional, often a pain management specialist, inserts a thin needle into the caudal epidural space through the sacral hiatus, an opening near the tailbone. To ensure accurate needle placement, imaging guidance, such as fluoroscopy (real-time X-ray), is used throughout the procedure. A small amount of contrast dye is injected, which helps confirm the needle’s position within the epidural space, as the dye’s spread pattern can be observed on the X-ray.
Once proper placement is confirmed, the therapeutic medication, a mixture of corticosteroid and local anesthetic, is administered. The entire procedure is quick, taking about 10 to 20 minutes, and is performed on an outpatient basis, meaning patients can go home the same day.
Potential Risks and Side Effects
While caudal injections are considered safe, some potential risks and side effects are associated with the procedure. Common side effects include temporary soreness, tenderness, or bruising at the injection site. Patients may also experience a temporary increase in pain before the steroid medication begins to take effect, or an unusual sensation in the affected leg for up to a week.
Less common but more serious risks, though rare, include infection at the injection site, bleeding (hematoma), or an allergic reaction to the medication or dyes used. A spinal headache, caused by spinal fluid leakage due to a dural puncture, occurs in less than 1% of people. Nerve damage or temporary issues with bladder and bowel control are extremely rare complications.
What to Expect After a Caudal Injection
After a caudal injection, patients are monitored for 30-60 minutes in a recovery area before being discharged. It is common to experience some temporary numbness or weakness in the legs for a few hours due to the local anesthetic. Some soreness or tenderness at the injection site is also expected and usually resolves within a few days.
Immediate pain relief may be felt due to the anesthetic, but this relief is temporary. The steroid component typically takes longer to work, with noticeable pain relief often beginning within two to three days, and sometimes up to 10 days. Patients are advised to avoid strenuous activities and driving for at least 24 hours after the procedure. Normal daily activities can usually be resumed the following day, though specific guidance from the medical professional should be followed. The duration of pain relief varies among individuals, lasting from weeks to several months, and repeat injections may be considered as part of a long-term pain management plan.