Assess the Effectiveness of Pulse RadioFrequency in Patients With Chronic Lumbar Radicular Pain

Pulsed RadioFrequency (PRF) is a relatively new technique derived from a well established and proven intervention, thermal radiofrequency (RF). Both procedures are used in the treatment of chronic pain. Unlike RF treatment, PRF does no direct damage to the nerve. During PRF treatment, electrical energy is applied with a small needle to the affected nerve using a pulsed time cycle that delivers short bursts of RF current. This study is interested in looking at the efficacy of PRF for chronic lumbar radicular pain (CLR) and to assess whether a larger scale clinical study with the same methods can be used.

Inclusion Criteria: * \> 18 years of age * CLR for at least 4 months of more, with concordant findings on either MRI and CT scan * VAS score of at least 60/100 at presentation * informed consent Exclusion Criteria: * \< 18 years of age * patient refusal * any contraindication to neuraxial injection such as coagulation disturbance, anticoagulant therapy, bleeding disorder, or infection at site of injection * anatomical deformity or derangement, either congenital or surgical such as: extreme scoliosis, previous implant or instrumentation making it difficult to access the foramen as evidence by MRI, CT, or plain x-rays * uncontrolled diabetes or severe coronary vascular disease necessitating continuation of anticoagulation therapy * known history of psychiatric illness-such as depression or psychosis * presence of cancer accounting for present symptoms * patient's inability of communicate in English and inability to understand and fill out the required follow-up questionnaire and form * allergy to local anesthetics or steroid or contrast medium * any patient with a history of acute neurological weakness or neurodeficit in the affected limb in terms of measurable motor weakness or abnormal reflexes