By Pat Anson, PNN Editor

Invasive procedures such as steroid injections, nerve blocks and radiofrequency ablation should be used more cautiously when treating chronic neck pain, according to new guidelines adopted by the American Academy of Pain Medicine and American Society of Regional Anesthesia and Pain Medicine.

The two medical societies formed a joint guidelines committee in 2020 to look into cervical spine joint procedures, which are increasingly used despite questions about their effectiveness and safety. The use of radiofrequency ablation -- heat from an electric current used to burn painful nerve endings — has increased by 112% in the U.S. over the past decade.

Spine pain in the neck or lower back is the leading cause of disability worldwide, with nearly half of adults likely to be affected at some point in their lives. The cervical facet joints, which allow the neck and back to tilt forwards, backwards and to rotate, are the primary source of pain in about 40% of patients with chronic neck pain and over half of those with neck pain after whiplash injury.

"It is precisely because neck pain and cervical spine procedures are so common, and there is so little high-quality evidence to guide care, that consensus guidelines are needed,” says lead author Steven Cohen, MD, a professor of anesthesiology at Johns Hopkins Hospital and co-chair of the guidelines committee.

The new guidelines, published online in the journal Regional Anesthesia & Pain Medicine, are based on over 400 publications and clinical studies of cervical spine procedures. Reviewers also looked at clinical signs and imaging used to select patients for particular procedures; the diagnostic and prognostic value of procedures; and several aspects of radiofrequency ablation (RFA), including how to reduce the risk of complications from the procedure and whether it should be repeated.

Because acute neck pain often resolves by itself, the guidelines recommend 6 weeks of conservative management, such as non-opioid painkillers and physical therapy, before opting for RFA or nerve blocks.

The reviewers found that RFA may be helpful for easing chronic neck pain, but only in patients whose pain corresponds to the joints being treated; those whose symptoms don’t emanate from a nerve root; and those who obtain meaningful pain relief from diagnostic nerve blocks, which are typically performed before RFA. 

Many insurance carriers require two nerve blocks, but the evidence indicates that doubling up will result in a significant number of unnecessary procedures and higher costs. Reviewers say the evidence for performing only a single block is much stronger for the neck than for the lower back.

The guidelines also recommend against stringent patient selection criteria, such as requiring nearly total pain relief from diagnostic blocks, because it might exclude patients who might benefit from radiofrequency ablation. None of the clinical studies that were reviewed support using pain relief thresholds above 50 percent.

Physicians should warn patients about the common side effects of RFA, such as tingling and burning sensations, numbness, dizziness, and loss of balance and coordination, which can last from a few days to a few weeks after the procedure. Patients also need to be told that RFA won’t cure them, and that pain relief typically lasts between 6 and 14 months. 

While most patients who have the procedure repeated will get pain relief, the benefits may wane over several years. RFA shouldn’t be repeated more than twice a year, the guidelines recommend.

Other key recommendations include:

• Use only soluble, short-acting steroids when injecting into the upper neck joints

• Use fluoroscopy imaging before spinal injections to avoid inadvertent needle placement

• Use smaller needles and electrodes than those used for the lower back

• Use nerve and muscle stimulation to improve effectiveness and reduce the risk of complications

• Take steps to minimize interference with implanted electrical devices such as pacemakers

“Clinical trials evaluating cervical facet blocks and RFA are characterized by widely disparate outcomes, and there is enormous variation in selecting patients and performing procedures. These multi-society guidelines have been developed to serve as a roadmap to improve outcomes, enhance safety, and minimize unnecessary tests and procedures,” the reviewers concluded.