PRF Treatment for Patients With Chronic Lumbosacral Radicular Pain Compared to Conventional Medical Management

Inclusion Criteria: * Symptoms more than 3 months 18,48 * Optimized conventional medical management at least for 1 month * Pain radiating into the leg, up to the hallux (big toe) (L5) or little toe (S1) * The pain in the leg dominates over a possible lumbalgia, the average pain in the leg measured 3 times a day, at predefined time points, over 4 consecutive days prior to inclusion should be more than 5 (NRS 10-point scale) 8 * Pattern of radiation suggestive for L5 or S1 pathology 49,50 * One or more positive neurological tests of nerve root tension or neurological deficit 51 ; straight leg raising test (SLRT), contralateral SLRT, motor reaction during SLRT and passive cervical flexion, motor reaction during passive cervical flexion while bending forward in standing position * Capable of understanding the information relative to the treatment and procedure and willing to provide informed consent * Capable of understanding and filling-out the questionnaires necessary for evaluation of the treatments * Patients having undergone low back surgery like discectomy with or without laminectomy are allowed to participate in the study Exclusion Criteria: * Patients younger than 18 years * Malignant disorder or currently under treatment for a malignant disorder * Previous lumbar fractures * Proven myelum lesion or abnormalities in the central neurological structures * Systemic or connective tissue diseases * Diabetes mellitus type I * Multiple sclerosis * Coagulation disorders * Pregnancy * Conventional medical management less then 1 month * Pain Catastrophizing Scale \> 45. When the patient has a higher score he/she will first be referred to a psychologist for consultation 52 * Leg pain due to localized hip or knee pathology * Patients with a pacemaker or neurostimulator * Patients previously treated with RF or PRF of the lumbar DRG