Phenol Versus Lidocaine in Obturator Nerve Neurolysis for Hip Joint Pain

Abstract

Introduction: For patients with severe hip osteoarthritis without clinical or socioeconomic conditions for total hip replacement, the obturator nerve block may serve for pain control and functional improvement. Either lidocaine or phenol are used, although the latter is expected to last longer. Objectives: Compare hip pain and functional performance after obturator nerve block with phenol versus lidocaine in patients with severe hip osteoarthritis who failed conservative treatment. Methodology: Forty-four patients scheduled for total arthroplasty due to severe osteoarthritis were randomized to the anterior branch of the obturator nerve with phenol (PG) or 1% lidocaine (LG), guided by electrical stimulation. Patients were evaluated with VAS, WOMAC, and pressure pain dolorimetry before the procedure and in the first and fourth months afterward. Results: Both groups improved significantly in pain control, pressure dolorimetry and functioning in the first month with reduced effect after 4 months, although the scores were still better than baseline. No statistical difference could be noticed between the groups. Severe adverse effects were not reported. Conclusion: Both lidocaine and phenol are equally effective and safe in the obturator nerve block for the control of pain and improvement in functioning in patients with severe hip OA. Evidence Level I; Randomized control trial, double-blind .