A Pilot Study of Full-Endoscopic Annulus Fibrosus Suture Following Lumbar Discectomy: Technique Notes and One-Year Follow-Up

Abstract

Background: An annulus fissure or defect will inevitably be left on the posterior annulus fibrosus after almost all kinds of lumbar discectomy, which may lead to unsatisfying postoperative pain relief and recurrence of the disc herniation. Objective: The objective of this research is to introduce the technique of full-endoscopic annulus fibrosus suture following lumbar discectomy through the transforaminal or interlaminar approach, and to analyze the clinical outcome of full-endoscopic lumbar discectomy and annulus fibrosus suture. Study Design: This study used a prospective cohort design. Setting: The research was conducted in a hospital and outpatient surgery center. Methods: A total of 50 patients with noncontained lumbar disc herniation treated with full-endoscopic lumbar discectomy and annulus fibrosus suture were treated in our department between January 2018 and November 2018. Full-endoscopic single-stitch suture via the transforaminal approach (Group T) or double-stitch suture via the interlaminar approach (Group I) was selected according to the level of lesion. Lumbar magnetic resonance imaging (MRI) was reexamined on the second day and 3 months after operation to evaluate the completeness of the discectomy and the adequacy of nerve decompression. Patients were followed up on the second day, 3 months, 6 months, and one year after operation to evaluate the relief of low back pain and leg pain, using a visual analog scale (VAS, 100-point scale). At 3 months, 6 months, and one year after operation, the patients were followed up for recovery of lumbar spine function, using the Oswestry Disability Index (ODI). At the one-year follow-up, the MacNab score was used to evaluate the clinical outcome, and the recovery of nerve root function (sensation, muscle strength, and reflex) was recorded. Results: All operations were successfully completed, including 27 cases in Group T and 23 cases in Group I. There were no surgical complications and no recurrence of lumbar disc herniation. Lumbar MRI reexaminations of all patients showed that the herniated disc was completely removed and the nerves were fully decompressed. Postoperative low back pain and leg pain were significantly relieved, and the ODI score was significantly improved (P < .01) in both groups. At the one-year follow-up, the excellent and good rates as measured by the MacNab score were 92.6% in Group T and 91.3% in Group I with no significant difference between the 2 groups (P > .05). The impaired sensation and muscle strength in the low extremities of evolved nerve root of the 2 groups of patients recovered significantly at the oneyear follow-up (P < .01), but the tendon reflex did not recover significantly (P > .05). Limitations: This is an observational cohort study with relatively small sample sizes and short-term follow-up. Conclusions: Full-endoscopic lumbar discectomy and annulus fibrosus suture through either the transforaminal or interlaminar approach are safe and effective minimally invasive spinal surgery techniques that can reduce the recurrence rate of lumbar disc herniation after full-endoscopic lumbar discectomy. Keywords: Annulus fibrosus suture; full-endoscope; lumbar disc herniation; lumbar discectomy; minimally invasive spinal surgery