Clinical Outcomes of Percutaneous Endoscopic Lumbar Discectomy for Adjacent Lumbar Disc Herniation after Lumbar Posterolateral Fusion by Radiologic Evaluations

ABSTRACT

STUDY DESIGN: A retrospective study. OBJECTIVE: To analyze the effectiveness of percutaneous endoscopic lumbar discectomy (PELD) for adjacent lumbar disc herniation through radiologic evaluations. SUMMARY OF LITERATURE REVIEW PELD minimizes posterior structural damage, allowing rapid rehabilitation. SUBJECTS AND METHODS: This study was conducted on 45 patients who were followed up for 1 year after PELD for adjacent lumbar disc herniation from March 2014 to February 2016. The modified Macnab criteria, the modified Suezawa and Schreiber score (MSS score), and visual analogue scales for the back (VAS-B) and legs (VAS-L) were evaluated. The disc height ratio and segmental angulation change were compared before posterolateral fusion and before PELD. Moreover, spinal stenosis was confirmed on magnetic resonance imaging (MRI) before PELD. RESULTS: Based on the modified Macnab criteria, 53.3% patients received an evaluation of at least “good,” and the mean MSS score improved from 4.77 to 6.99 at 1 year after the operation. The mean VAS-B score decreased from 7.02 to 4.67, and the mean VAS-L score decreased from 8.15 to 4.24 at 1 year after the operation. The mean disc height ratio was 87.1%, and the mean segmental angulation change was 6.5°, with a greater change in the “fair” or “poor” group, and the rate of spinal stenosis on MRI was also higher in the “fair” or “poor” group. CONCLUSION: The clinical outcomes of PELD, which is accompanied by degenerative changes on simple radiographic images such as disc space narrowing and increased segmental angulation or spinal stenosis on MRI, may not be satisfactory. Therefore, decisions regarding surgery should be made carefully in such cases.