Cryoneurolysis, cryoneurotomy, or “Cryo” refers to a technique of nerve ablation using the application of extreme cold (usually -60 degrees Celsius) to freeze body tissue and interrupt painful nerve signals. The nerves will regenerate but the median duration of pain relief is 9-12 months.
Cryo can be used for spine arthritis, sacroiliac joint pain, occipital neuralgia, post inguinal hernia pain, Morton’s neuroma, and many other forms of nerve pain. It cannot be used on major spinal nerve roots that carry motor signals to the body.
Cryo is only performed after isolating the precise pain generators and confirming that nerve blocks using local anesthetic substantially reduces the pain.
Cryo is a temporary procedure. The nerve body resides in the spinal cord and is not damaged. Cryo is performed on the nerve arm (called an axon). The arm dies back and then the body grows a new arm along the same path at a rate of approximately 1 mm per day. Sensation is restored when the nerve reaches its intended target. Permanent lesions are not usually performed because of the potential to cause painful neuromas to grow at the site of the lesion.
It is very important that you continue to perform regular exercise including stretching, strengthening, and aerobic exercise during the period of reduced pain following neurolysis. Patients who exercise regularly will have a longer duration benefit and are less likely to have their pain recur. Patients who do not exercise may notice that the procedure becomes less effective over time or it may stop working entirely.
How is cryo performed?
The procedure is performed at the Helmcken Pain Clinic under fluoroscopic (x-ray) or ultrasound guidance. The correct location will be identified using x-ray or ultrasound after which the skin will be sterilized. Local anesthetic is used to numb the skin and tissues after which you should not feel anything for the duration of the procedure. Make sure to tell the doctor if you do feel pain during the procedure so extra local anesthetic can be added. Sedation is rarely required but if you have severe needle phobia you may want to discuss having an oral sedative prescribed.
What will I feel afterward?
Depending on where the injection was performed you may feel nothing at all, a bit numb or some mild discomfort. When the local anesthetic wears off you will feel increased discomfort that may last for up to a week. You can apply ice packs (20 minutes on and 20 minutes off) and take Tylenol or Advil. Sometimes a stronger painkiller will be prescribed. You can perform exercises and other physical activities as tolerated. Depending on your occupation you may need a few days off work. Please discuss this with your doctor prior to the procedure. You can resume driving when you feel ready although have to wait at least 24 hours if sedation was used.
What are the risks?
Risks associated with any injection include: infection at the site of the injection, increased inflammation and pain at the site of the injection, bleeding, bruising, injury to blood vessels or nerves, and allergic reaction to the local anesthetic or other medications used during the procedure. There may be other specific risks depending on the location of the injection.
Negative side effects of Cryo include 1-2 weeks of aggravated pain due to local tissue trauma and numbness in the sensory distribution of the nerve. Cryo can cause a small area of skin irritation or numbness that can persist for several months (called neuralgia or neuritis). Patients have described this sensation as similar to sunburn, itch, or a sensation like something is touching their skin in that area. It is usually mild but severe reactions have been known to occur. It can usually be treated with a topical local anesthetic cream.
Can Cryo cure me?
No, neurolysis is designed to take away some of or all your pain but does not cure the underlying process. Unfortunately, when it comes to arthritis and nerve injuries nothing will cure or reverse the underlying problem. Pain, on the other hand, may go away in time.
Will the absence of sensation cause me to injure the area more?
Generally speaking no. If you have an area of numbness on your skin after the procedure then this area is at risk of being injured by excessive application of heat or cold. Additionally, you may not be able to feel a cut or object rubbing the area. It is important that you inspect any areas of numbness, particularly on the feet or hands, on a regular basis to ensure that skin injuries have not occurred.
Chronic pain is very different from acute pain. Acute pain, such as occurs right after an injury, is designed to protect your body from further damage and allow healing to occur. The body does this by creating pain and tightening the muscles around the area of injury. Pain that persists after healing has been completed is chronic pain and can be best understood as failure of the body to shut down its protective mechanisms. Chronic pain is not protective and can in fact cause damage and other health problems by making you less likely to exercise or move your muscles / joints leading to stiffness and muscle pain.
Please note that we are asking patients to pay a fee for specialized medications used during the procedure. Please discuss this with your physician if you feel that you cannot afford this fee.