1. 2021;24;E1291-E1298Clinical Outcomes of Percutaneous Endoscopic Lumbar Discectomy for the Treatment of Grade I and Grade II Degenerative Lumbar Spondylolisthesis: A Retrospective Study With a Minimum Five-Year Follow-up
   Retrospective Case Series
   Lei Zang, MD, Wenyi Zhu, MD, Lihui Yang, MD, Jian Li, MM, Peng Du, MM, Shuo Yuan, MD, Ning Fan, MD, and Qichao Wu, MD.

BACKGROUND: Degenerative lumbar spondylolisthesis (DLS) occurs mainly in geriatric patients. Some authors have reported satisfactory short-term outcomes following percutaneous endoscopic lumbar discectomy (PELD) for DLS; however, the long-term clinical outcomes remain unknown. In addition, it remains unclear whether PELD causes further progression of spondylolisthesis over a long period of time.

OBJECTIVES: To evaluate long-term clinical outcomes in patients who underwent PELD and to study the degree of slippage in DLS over a long period following minimally invasive surgery.

STUDY DESIGN: Retrospective case series.

SETTING: The study was conducted at the Beijing Chaoyang Hospital, Capital Medical University, China.

METHODS: The study included 24 patients with DLS who complained of radicular pain and lower back pain who underwent PELD and were followed up for at least 5 years (mean duration of 6.1 years). Visual analog scale (VAS) scores, Oswestry disability index (ODI) scores, and the modified MacNab criteria were used to evaluate clinical outcomes. Preoperative imaging findings, including the percent slippage of spondylolisthesis (SR), disc height (DH), segmental lordosis angle (SL), and lumbar lordosis angle (LL), were compared with those obtained at follow-up.

RESULTS: All operations were successfully completed; the mean operative incision length, intraoperative blood loss, and operation duration were 8.7 ± 0.6 mm, 11.3 ± 4.5 mL, and 121.8 ± 32.3 min, respectively. The mean VAS-back score, VAS-leg score, and ODI score were 6.5 ± 0.9, 6.0 ± 1.1, and 55.4 ± 4.4 points before surgery, respectively, and decreased to 2.6 ± 0.8, 2.2 ± 0.5, and 27.3 ± 5.3 points, respectively, at 3 months after surgery and 2.5 ± 0.9, 2.0 ± 0.5, and 21.1 ± 4.4 points, respectively, at the latest follow-up. The imaging variables related to DH were lower at the final follow-up before surgery; however, no significant differences in SR, SL, and LL were found. The proportion of excellent and good results following MacNab evaluation was 87.5%. Symptomatic re-herniation occurred in one patient, and cerebrospinal fluid leakage (CSFL) was found in another patient.

LIMITATIONS: A small number of patients were included who were all treated by one surgeon.

CONCLUSIONS: PELD maintained satisfactory clinical outcomes for the treatment of grade I and grade II DLS after a minimum 5-year follow-up; the operation did not cause further progression of spondylolisthesis. However, further large-scale multicenter studies are necessary.

KEY WORDS: Spondylolisthesis, percutaneous endoscopic lumbar discectomy, minimally invasive, clinical outcome, geriatric patients, spine, lumbar instability, comorbidities