Peripheral Nerve Blockade

Local anaesthetic peripheral nerve injection

 

Even when it gives a relatively short length of action it can be useful in helping to diagnose the cause of the pain.

 

The aim is to get the local anaesthetic as close to the nerve as possible to ensure that as much of the nerve as possible is exposed to it. For this purpose we are using ultrasound that allows us to visualize nerve, needle, and blood vessels.

 

The block is usually done somewhere between the source of the nerve injury and it's connection to the spinal cord.

 

If repeated several times, some patients notice a significant reduction in their neuralgic pain which outlasts the theoretical length of action of the local anaesthetic. This may be due to some form of neuromodulation in the dorsal horn on the spinal cord.

Peripheral nerve blocks have long been used in headache treatment. The most widely used procedure for this purpose has been greater occipital nerve (GON) block. The rationale for using GON block in headache treatment comes from evidence for convergence of sensory input to trigeminal nucleus caudalis neurons from both cervical and trigeminal fibers. Several studies suggested efficacy of occipital nerves blockadein the treatment of migraine, cluster headache, and chronic daily headache.

Spinal Nerve Blockade

Spinal Blocks are diagnostic procedures that help to determine the source of patients' back pain. They may also temporarily relieve pain.

There are two main types of blocks - facet blocks (medial branch nerve blocks) and selective nerve root blocks.

Facet Block

Facet joints, which connect bones in the spine, facilitate motion. Each vertebra has two sets of facet joints: one pair faces upward and one downward. The joints, which are located at the back of the spine, are like hinges that link the vertebrae together. Each facet joint is innervated by a medial branch nerve. The capsule serves to limit bending forces and to resist a backwards sliding motion during banding backwards. This capsule is highly innervated with pain nerve fibers. The facet joints play an important role in limiting rotation about to the spinal disc.

The precise cause of most facet joint pain remains unclear. The facet joint pain is variable. Often the pain is localized only to the back. However, sciatic type pain has also been observed. During hyperextension, the capsule stretches. This may cause pain. Arthritic changes of the facet joint can also cause low back pain.

Signs and Symptoms

Most patients often only have low back pain. However, some patients complain of radiating pain, which occasionally travels into the buttocks and into the lower extremities.

Selective Nerve Root Block

Nerve roots are attached to the spine and grow out of each side of the spinal column at every spinal level. They carry signals throughout the body from the skin to the muscles. When one of the nerve roots is irritated, patients may experience pain, numbness, tingling and sometimes weakness down an arm or a leg.

Block procedures are helpful in discovering whether a nerve root or one or more facet joints are injured or stressed.

Spinal Block Procedures

A block involves the passing of a small needle full of an anesthetic or numbing medication into the area of a specific nerve root or facet joint. The entire procedure usually takes anywhere from a half an hour to an hour, depending on how many joints are injected.

If your procedure is scheduled in the morning, please don't drink any liquids or eat any solid foods after midnight. If your block is scheduled in the afternoon, you may have water or apple juice that morning, up to two hours before the procedure. If you are taking any blood thinners such as Coumadin and Plavix, you must stop taking them a week before your block. Let your primary care doctor and your physician know before you stop taking your blood thinners.

You will be placed on your stomach and your back will be numbed with a local anesthetic before the needle is inserted in your back. Once the needle is in place, you may feel some pressure or mild discomfort, but this only lasts a few seconds. When the procedure is over, the numbing medicine may make your legs feel temporarily weak. Therefore, you should limit your activity on the day of your procedure. Someone should accompany you home if you were given sedative medication before procedure because you will not be able to drive. You can usually resume normal activity the day after your procedure.

You may experience bruising or tenderness at the injection site(s) and your pain may get worse a day or two after the block. Please call our office if you develop a fever greater than 100.5 degrees, experience any unusual pain symptoms or if the weakness in your legs persist. Even if you don't have any unusual symptoms, we'd like to hear from you the day after your procedure to see how much pain relief you get from the block and how long the pain relief lasts.