Lumbar Sympathetic Block
Back Pain Treatments in Colorado
A lumbar sympathetic nerve block involves injecting a nerve bundle of the
lower back with medication. This procedure is used to diagnose and treat
back pain disorders that cause symptoms involving the lower extremities,
which are sustained by the sympathetic nervous system.
What is the sympathetic nervous system (SNS)?
The SNS is the network of nerves that are linked to numerous neuropathic
pain syndromes. The role of the SNS in the transmission of pain signals
involves the nerves that are associated with adaptive physical reactions.
The SNS constricts blood vessels and controls sweating. To block these
nerves, the doctor uses an anesthetic, neurolytic agent, or radiofrequency energy.
What conditions are treated using the lumbar sympathetic nerve block?
Injury or irritation to the sympathetic nerves can affect the feet and
lower extremities. This causes a condition called complex regional pain
syndrome. The main symptom of CRPS is an intense, burning pain in the
lower extremities. Another condition treated is sympathetically maintained
pain (SMP), or pain that is facilitated by the SNS activity.
What symptoms are relieved using the lumbar sympathetic block?
Allodynia (pain from slight touch) and hyperalgesia (severe irritation
and pain) are symptoms associated to the SNS. The lumbar sympathetic block
is used to treat these symptoms. Low-threshold sensory fibers are activated
and excite neurons in the spinal cord that typically do not respond to
such stimuli. When sympathetic pain goes untreated, it often becomes chronic
How do I prepare for the lumbar sympathetic nerve block?
You will first meet with the pain specialist who evaluates your condition.
After reviewing your medical history, conducting an exam, and doing some
diagnostic tests, the doctor schedules your procedure. He will review
the risks and benefits with you before you sign a consent form. Because
increased bleeding can occur, you should avoid any blood thinning medications
for several days before the procedure. Arrange to have someone drive you
home, do not eat or drink six hours before your appointment, and leave
all valuables at home.
How is the lumbar sympathetic block done?
The Colorado pain doctor uses fluoroscopy (real-time x-ray) to visualize
the area being injected. Live images on a monitor allow the doctor to
position the needle close to the nerves. After you are positioned face-down
on the procedure table, a nurse administers a sedative. One your back
has been cleansed with an antimicrobial solution, the area is numbed with
an anesthetic. The procedure needle is inserted, medications are instilled,
and the needle is then removed. A small bandage will be secured to the
Does the lumbar sympathetic nerve block work?
Many clinical trials have proven the efficacy of the lumbar sympathetic
nerve block. In a Japanese study, nerve blocks were found to decrease
the pain intensity and lower opioid consumption without any serious side
effects. A recent randomized controlled study found that this block was
more effective than placebo, and patients had remarkable pain reduction
after the procedure. The block was also found useful for treating the
pain of abdominal and pelvic cancer. Additionally, the lumbar sympathetic
nerve block using a neurolytic agent was found to produce long-term pain
relief in patients with interstitial cystitis.