Methylene blue is a low-molecular weight chemical dye that possesses anti-inflammatory properties. It is used to treat irritated intervertebral discs and is effective in minimizing and treating discogenic (involving one or more intervertebral discs) low back pain.
What is Intradiscal/Discogenic Low Back Pain?
Discogenic low back pain does not involve spinal deformity or instability in your spine. It may occur due to sensitization of nociceptive nerves. Therefore, management of intradiscal pain involves controlling the growth of nerve fibers and nerve endings into the disc. This could be achieved through the following mechanisms:
- Minimizing inflammation
- Reducing intradiscal pressure
- Removal or destruction of intradiscal nociceptors through ablation
Indications: Who is a Suitable Candidate for an Intradiscal Methylene Blue Injection?
Intradiscal methylene blue injection may be recommended under for the following conditions:
- People in the age group ranging from 20 to 75 years
- When other conventional techniques such as medications and physical therapy are ineffective
- Chronic low back pain with a duration lasting more than 6 months
- Pain worsens on prolonged sitting
- You do not have neurological abnormalities in any of your lower extremities
Contraindications for Intradiscal Methylene Blue Injection
People with the following conditions are not recommended for an intradiscal methylene blue injection:
- Severe disc degeneration
- Sequestered or extruded herniated disc
- Instability in the lumbar spine
- Radicular pain in the lower extremity
- Previous history of surgery at lumbosacral region
- Spinal infection
- Spinal tumor
- Psychiatric disease
What is the Mechanism of Action of Methylene Blue?
Methylene blue is partially soluble in lipids (fats). It inhibits the enzyme nitric oxide synthase (NO synthase) and nitric oxide that bring about inflammatory changes such as disc degeneration and discogenic pain. Thus, when it is injected as an intradiscal injection, it inhibits nitric oxide production.
Methylene blue acts as a neurolytic block which means it brings about damage (ablation) to the sensory nerves in the intervertebral disc. This minimizes pain sensation and provides pain relief. Doctors use methylene blue in a planned manner to provide relief from chronic low back pain.
Methylene blue helps treat intradiscal pain and thus, reduces your need to undergo a surgery.
How is Methylene Blue Administered?
You will be asked to change your clothes and wear a surgical gown. You will be placed in prone position on your stomach. The injection site will be sterilized using anti-infective agents such as povidone iodine.
The location of pain, that is the targeted intervertebral disc, is specified with the use of imaging tests such as lumbar discography. This is done using a surgical needle under local anesthetic. The needle is inserted into your spinal column to ascertain the location of pain. After the source has been identified, methylene blue is injected into the targeted intervertebral disc at a specific dose and controlled speed.
What are the Do’s and Don’ts after an Intradiscal Methylene Blue Injection?
After receiving the methylene blue injection, you will be advised rest for a few hours. During this time, you be monitored for any abnormal symptoms. You will be discharged on the same day and advised to avoid strenuous exercise and heavy work for 2 weeks.
What are the Advantages of Methylene Blue Injection for Intradiscal Pain?
The advantages of methylene blue injection include:
- Provides relief from a chronic disc low back pain
- Minimally invasive technique
- Quick recovery time