Prevention of lumbar reherniation by the intraoperative use of a radiofrequency bipolar device: A case-control study

Abstract

Objective: The most common complication after lumbar discectomy is reherniation. Although many studies have investigated factors that may increase the reherniation risk, few are agreed upon all. It has been suggested that limited nucleus removal is associated with higher reherniation risk, while more aggressive nucleus removal can result in increased disc degeneration. Here, we assessed the efficacy of a coblation-assisted microdiscectomy in adult patients undergoing single-level disc surgery.

Methods: We prospectively compared the reherniation rate in 75 patients (Group 1) undergoing single-level lumbar disc surgery completed with the radiofrequency bipolar system Aquamantys^® (Medtronic, Minneapolis, MN, USA) to that of a historical control group (n = 75) matched for variables related to herniation level and characteristics (Group 2). Patients were followed up to 4 years. Reherniations were assessed, pain and function were monitored throughout, and imaging was performed at annual follow-up.

Results: The overall symptomatic reherniation rate was 4%. In particular, one case (1.3%) was observed in Group 1 and five (6.7%) in Group 2 (P < 0.05). Magnetic resonance imaging identified a total of 4 (2.7%) asymptomatic reherniations at 12 months, 6 (4%) at 24 and 36 months, and 7 (4.7%) at 48 months. Overall, Group 1 contained one (1.3%) asymptomatic reherniation case, while six (8%) were observed in Group 2 (P < 0.05).

Conclusions: The low reherniation rate in patients treated by the coblation-assisted microdiscectomy suggests that this technique may reduce the reherniation risk. Clinical outcomes for pain and function at 4 years follow-up compared favorably with literature data. Randomized controlled trial could confirm these results.

Keywords: Discectomy; radiofrequency; recurrent herniation; reherniation.

Figure 1

Graphs showing (a) Oswestry Disability Index, (b) Visual Analog Score for leg (c) and back pain for both Groups assessed preoperatively and over the entire follow-up. Significant reductions in Visual Analog Score and Oswestry Disability Index were observed at 1 month relative to baseline in both groups (*P < 0.05). Those reductions were maintained at 48 months in both groups without significant differences between the groups (P > 0.05)

Figure 2

Bar graph showing symptomatic and asymptomatic reherniation cases for both Groups as observed at the end of the follow-up. One reherniation case was observed in Group 1 (1.3%) and 5 (6.7%) in Group 2 (*P < 0.05). Magnetic resonance imaging identified one (1.3%) asymptomatic reherniation in Group 1 and 6 (8%) in Group 2 (*P < 0.05)