Differential Treatment of Nerve Root Compression Pain Caused by Lumbar Disc Herniation Applying Nucleoplasty

Abstract

Background: Nucleoplasty is a minimally invasive intervention use to perform disc decompression in cases of nerve root compression caused by disc herniation. It is important to find rational guidelines for choosing between nucleoplasty and microsurgery. Objective: To analyze factors that may impact the results of nucleoplasty, and to validate the rational guidelines between minimally invasive treatment and open surgery. Study Design: Prospective, non-randomized, cohort study with a minimal follow-up period of 18 months. Methods: Patients were given a neurological examination, visual analogue scale and Oswestry disability questionnaire, obligatory MRI, optional RCT, and discography, only before nucleoplasty. Patients have been divided into the following groups: Group 1 – patients with a disc protrusion treated with nucleoplasty (n = 46), which has been divided into Subgroup 1A, those with a disc protrusion size ≤ 5 mm (n = 24), and Subgroup 1B, those with a disc protrusion size 6 – 9 mm (n = 22); Group 2 – patients with a disc extrusion treated with nucleoplasty (n = 27); Group 3 – patients with a disc extrusion or sequester treated with microdiscectomy (n = 65). Outcome Measures: Clinically significant outcomes were a 50% relief of pain intensity and a 40% decrease of Oswestry Disability Index (ODI). Results: A decrease of pain intensity and disability was found in all groups of patients, P < 0.0001; SP (statistical power) = 99 – 100%. Subgroups 1A and 1B showed no clinically significant differences in outcome, P = 0.99; SP = 5.3. Clinically significant results: Group 1 – 78%; 95% CI (confidence interval) [66; 90%], Group 2 – 44%; 95% CI [25; 65%], Group 3 – 93%; 95% CI [85; 98%]. Total annulus disruption increases the rate of unsatisfactory results of nucleoplasty, OR (odds ratio) = 4.5; 95% CI [1.57; 12.87] (logistic regression model, P = 0.0034). Nucleoplasty performed in cases of uncontained disc herniation (disc extrusion) have a significantly higher rate of unsatisfactory results versus microdiscectomy, OR = 19.06; 95% CI [2.29; 68.73] (logistic regression model, P < 0.0001). Limitations: This study was limited by the small number of patients in each group. Conclusion: The size of the disc protrusion does not significantly affect the outcome of nucleoplasty. The rational guideline for choosing between the 2 types of surgery is the integrity of the annulus. Key words: disc herniation, nucleoplasty, microdiscectomy, annulus integrity