Percutaneous endoscopic lumbar discectomy for L5-S1 disc herniation based on image analysis and clinical findings: A retrospective review of 345 cases

Abstract

The effect of spinal anatomical anomalies on the efficacy of percutaneous endoscopic lumbar discectomy (PELD) for disc herniation repair is unclear. This retrospective review aims to assess the safety and effectiveness of PELD for treating L5-S1 disc herniation with a range of characteristics and to determine the prevalence of lumbosacral transitional vertebrae (LSTV) anatomical anomalies to facilitate pre-surgical planning. From July 2005 to June 2019, 345 patients with L5-S1 disc herniations were treated with PELD. The primary outcome was 1-year postoperative visual analogue scale scores for low back and lower limb pain. The secondary outcomes included the surgical approach used, lumbosacral bony anomalies, presence of a ruptured disc or severely calcified disc, pediatric lumbar disc herniation, recurrent disc herniation management, and the long-term outcome. visual analogue scale scores for most patients were significantly improved after surgery. The prevalence of LSTVs was 4.05% (14/345 patients) in lumbar sacralization and 7.53% (26/345 patients) in sacral lumbarization. The prevalence of ruptured and severely calcified discs was 18.55% (64/345) and 5.79% (20/345), respectively. The prevalence of pediatric lumbar disc herniation was 2.02% (7/345). The recurrence rate was 4.34% (15/345). Two durotomy cases without sequelae and 8 cases of lower limb dysesthesia lasting longer than 3 months postoperatively were reported. PELD is safe and effective for treating L5-S1 disc herniation, including cases complicated by calcified lumbar disc herniation, disc rupture with migration, and the presence of LSTV. Appropriate imaging is essential to identify case-specific factors, including the prevalent LSTV anatomical anomalies, before surgery.

Figure 1.

The transforaminal approach on the L5-S1 level was used to indicate the lower iliac crest condition. (a, b) A 41-years-old female presented with low back pain and painful numbness radiating to the left buttock and a history of more than 1 year of left lower limb pain.

Figure 2.

The number of patients followed and the mean VAS score according to the medical record before surgery, then at 1 week, 3 months, and 1-year post-surgery. The line graph showed VAS scores for low back pain and lower limb pain, respectively, in the follow-up period. VAS = visual analogue scale.

Figure 3.

Two patients with lumbosacral transitional vertebrae. (a-d) A 36-year-old male presented with low back pain with pain radiating to the right lower limb for 3 months. (a, b) Radiographs of the lumbar spine showed L5 sacraliation. (c, d) Preoperative MRI showed L4-S1 disc herniation with downward migration of the right ruptured disc. (e-h) A 26-years-old male presented with right buttock pain radiating to the right lower limb. (e, f) Radiographs of the lumbar spine showed S1 lumbarization. (g, h) Preoperative MRI showed L5-S1 disc herniation on the right side. MRI = magnetic resonance imaging.

Figure 4.

A 23-years-old male presented with low back pain and a 2-year history of painful numbness radiating to the left lower limb. (a, b, c) Radiographs of the whole spine showed the presence of the sixth lumbar vertebra. (d, e) Preoperative MRI showed L6-S1 disc herniation to the left side. MRI = magnetic resonance imaging.

Figure 5.

Three patients with a ruptured disc with or without migration. (a, b) A 41-year-old male with a ruptured disc and upward migration. (c, d) A 36-years-old male with a ruptured disc and downward migration. (e, f) A 37-years-old female with a ruptured disc and no migration.

Figure 6.

A 21-year-old female presented with low back pain and a 3-month history of painful numbness radiating to the right lower limb. (a, b) Preoperative CT showed calcified disc herniation at the L5-S1 level. (c, d) Preoperative MRI showed disc herniation dominant to the right side. CT = computed tomography, MRI = magnetic resonance imaging.

Figure 7.

A 14-year-old girl presented with low back pain and an 8-month history of painful numbness radiating to the right lower limb. (a, b) Preoperative MRI showed disc herniation at the L4-5 and L5-S1 levels, especially at the L5-S1 level. (c, d) Postoperative MRI showed that the herniated disc had been removed, and both S1 roots were decompressed. MRI = magnetic resonance imaging.