title: Analysis of the Characteristics and Clinical Outcomes of Percutaneous Endoscopic Lumbar Discectomy for Upper Lumbar Disc Herniation.
abstract: BACKGROUND
  Lumbar disc herniations at the L1-L2 and L2-L3 levels have unique characteristics that result in worse surgical outcomes after traditional microdiscectomy compared with herniation at L3-L4. The purpose of this study was to evaluate the characteristics, clinical presentation, and outcomes of patients who underwent percutaneous endoscopic lumbar discectomy (PELD) at L1-L2 and L2-L3, compared with those who underwent PELD at L3-L4.
  
  
  METHODS
  We retrospectively evaluated the clinical data from 55 patients who underwent PELD for single-level lumbar disc herniation between 2008 and 2014, at a mean follow-up of 29.9 ± 16.4 months (12-month minimum; effective rate, 89.1%). Surgical duration; length of postoperative hospital stay; hospitalization cost; recurrence rate; Macnab criteria assessment; visual analog scale (VAS) of back pain, leg pain, and numbness; Japanese Orthopedic Association (JOA) low back pain score; and Oswestry Disability Index (ODI) before and after surgery were evaluated.
  
  
  RESULTS
  In the L1-L3 group, 76.9% of the patients had a positive femoral stretch test, compared with only 42.8% of those in the L3-L4 group (P < 0.05). Of the 49 patients with adequate follow-up, 17 (34.7%) exhibited excellent improvement, 23 (46.9%) had good improvement, and 6 (12.2%) had fair improvement according to the Macnab criteria. The VAS scores for back pain, leg pain, and numbness decreased significantly postoperatively in both groups, as did all other outcome measures (P < 0.05).
  
  
  CONCLUSIONS
  PELD is a safe and effective treatment for upper lumbar disc herniation and may compare favorably with the same procedure for lower lumbar disc herniation. In addition, the positive femoral stretch test was a relatively good diagnostic method for disc herniation at L1-L2 and L2-L3, compared with herniation at L3-L4.
authors.affiliation: Department of Orthopedics, Xinqiao Hospital, Third Military Medical University, Chongqing, China.
authors.forename: Junlong
authors.initials: J
authors.lastname: Wu
authors.affiliation: Department of Orthopedics, Xinqiao Hospital, Third Military Medical University, Chongqing, China.
authors.forename: Chao
authors.initials: C
authors.lastname: Zhang
authors.affiliation: Department of Orthopedics, Xinqiao Hospital, Third Military Medical University, Chongqing, China.
authors.forename: Wenjie
authors.initials: W
authors.lastname: Zheng
authors.affiliation: College of Medicine, The Ohio State University, Columbus, Ohio, USA.
authors.forename: Christopher S
authors.initials: CS
authors.lastname: Hong
authors.affiliation: Department of Orthopedics, Xinqiao Hospital, Third Military Medical University, Chongqing, China.
authors.forename: Changqing
authors.initials: C
authors.lastname: Li
authors.affiliation: Department of Orthopedics, Xinqiao Hospital, Third Military Medical University, Chongqing, China. Electronic address: happyzhou@vip.163.com.
authors.forename: Yue
authors.initials: Y
authors.lastname: Zhou
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D004185:Disability Evaluation; D017587:Diskectomy, Percutaneous / Q000379:methods*; D004724:Endoscopy / Q000379:methods*; D005260:Female; D006801:Humans; D007405:Intervertebral Disc Displacement / Q000000981:diagnostic imaging / Q000601:surgery*; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000601:surgery; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D012720:Severity of Illness Index; D016896:Treatment Outcome; D064232:Visual Analog Scale; D055815:Young Adult
keywords: Percutaneous endoscopic lumbar discectomy; Surgical outcome; Upper lumbar disc herniation