By Amy Price PhD
Radio Frequency Ablation (Denver Pain Management ,2009)
Radiofrequency (RF) and pulsed radiofrequency (PRF) neurolysis are techniques used to treat chronic pain that is transmitted through the sensory nerves. RF neurolysis utilizes heat to destroy selected nerve fibers, which block pain transmission through the neural pathway. These techniques are used when intermittent anesthetic injections no longer provide extended pain relief.
Chronic cervical, lumbar and sacral pain can come from your facet joints. These pain signals can be interrupted by blocking the nerve to the facet joint with an anesthetic injection this is very temporary (facet block), For longer lasting relief the nerve can be heated using a radiofrequency wave (radiofrequency ablation) . This can often prevent the neural transmission of pain. The nerve to the facet joint is sometimes referred to as the “medial branch” and therefore a facet nerve block is also referred to as “medial branch” block. These blocks are performed as a part of a diagnostic workup for back or neck pain. Relief following a precise injection of local anesthetic confirms the facet joint as the source of pain.
Radiofrequency neurolysis is a procedure in which sensory afferent nerve fibers are selectively destroyed with heat produced by radio waves delivered through an electrode. Treatment objectives are to eliminate pain, reduce the likelihood of recurrence and prolong the time to recurrence by selectively destroying pain fibers without inducing excessive sensory loss, motor dysfunction, or other complications. Radiofrequency (RF) neurolysis carries the potential risk of neuritis (nerve inflammation). Histological studies have revealed indiscriminate destruction of both small and large fibers following RF treatment.
Pulsed radiofrequency is thought to be a less destructive alternative to standard RF in that it applies RF energy with a pulsed time cycle that delivers short bursts of RF current instead of a continuous RF flow. By pulsing the electrical current, the needle remains relatively cool (up to 42 degrees celsius compared to temperatures of 60-69 degrees celsius with continuous RF) so that the tissue cools slightly between each burst, reducing the risk of destroying nearby tissue and preventing any long-term damage to the nerve. The reasoning behind this is transmission of impulses across small unmyelinated fibers is disrupted while larger fibers remain protected by the myelin sheath.
Some researchers show short term success with pulsed radio frequency in comparison to radio frequency lesioning. However others are reporting success rate of over nineteen months. It would seem that results could be altered by the skill of the spine care practitioner it is crucial to choose carefully.
