1. 2016;19;E1123-E1134Lower Learning Difficulty and Fluoroscopy Reduction of Transforaminal Percutaneous Endoscopic Lumbar Discectomy with an Accurate Preoperative Location Method
   Retrospective Evaluation
   Guoxin Fan, MD, Xin Gu, MD, Yifan Liu, MD, Xinbo Wu, MD, Hailong Zhang, MD, Guangfei Gu, MD, Xiaofei Guan, MD, and Shisheng He, MD.

BACKGROUND: Transforaminal percutaneous endoscopic lumbar discectomy (tPELD) poses great challenges for junior surgeons. Beginners often require repeated attempts using fluoroscopy causing more punctures, which may significantly undermine their confidence and increase the radiation exposure to medical staff and patients. Moreover, the impact of an accurate location on the learning curve of tPELD has not been defined.

OBJECTIVE: The study aimed to investigate the impact of an accurate preoperative location method on learning difficulty and fluoroscopy time of tPELD.

STUDY DESIGN: Retrospective evaluation.

SETTING: Patients receiving tPELD by one surgeon with a novel accurate preoperative location method were regarded as Group A, and those receiving tPELD by another surgeon with a conventional fluoroscopy method were regarded as Group B.

METHODS: From January 2012 to August 2014, we retrospectively reviewed the first 80 tPELD cases conducted by 2 junior surgeons. The operation time, fluoroscopy times, preoperative location time, and puncture-channel time were thoroughly analyzed.

RESULTS: The operation time of the first 20 patients were 99.75 ± 10.38 minutes in Group A and 115.7 ± 16.46 minutes in Group B, while the operation time of all 80 patients was 88.36 ± 11.56 minutes in Group A and 98.26 ± 14.90 minutes in Group B. Significant differences were detected in operation time between the 2 groups, both for the first 20 patients and total 80 patients (P < 0.05). The fluoroscopy times were 26.78 ± 4.17 in Group A and 33.98 ± 2.69 in Group B (P < 0.001). The preoperative location time was 3.43 ± 0.61 minutes in Group A and 5.59 ± 1.46 minutes in Group B (P < 0.001). The puncture-channel time was 27.20 ± 4.49 minutes in Group A and 34.64 ± 8.35 minutes in Group B (P < 0.001). There was a moderate correlation between preoperative location time and puncture-channel time (r = 0.408, P < 0.001), and a moderate correlation between preoperative location time and fluoroscopy times (r = 0.441, P < 0.001). Mild correlations were also observed between preoperative location time and operation time (r = 0.270, P = 0.001). There were no significant differences in preoperative back visual analogue scale (VAS) score, postoperative back VAS, preoperative leg VAS, postoperative leg VAS, preoperative Japanese Orthopaedic Association (JOA) score, postoperative JOA, preoperative Oswestry disability score (ODI), or postoperative ODI (P > 0.05). However, significant differences were all detected between preoperative abovementioned scores and postoperative scores (P < 0.05). Moreover, there was no significant differences in Macnab satisfaction between the 2 groups (P = 0.179). There were 2 patients with recurrence in Group A and 3 patients in Group B. Twelve patients with postoperative disc remnants were identified in Group A and 9 patients in Group B. No significant difference was identified between the 2 groups (P = 0.718).

LIMITATIONS: The preoperative lumbar location method is just a tiny step in tPELD, junior surgeons still need to focus on their subjective feelings during punctures and accumulating their experience in endoscopic discectomy.
CONCLUSIONS: The accurate preoperative location method lowered the learning difficulty and reduced the fluoroscopy time of tPELD, which was also associated with lower preoperative location time and puncture-channel time.

Key words: Learning difficulty, fluoroscopy reduction, transforamimal percutaneous endoscopic lumbar discectomy, preoperative locationLearning difficulty, fluoroscopy reduction, transforamimal percutaneous endoscopic lumbar discectomy, preoperative location