Abstract

[Introduction] Percutaneous Endoscopic Lumbar Discectomy (PELD) is a one-night stay surgery with a 7mm incision under local anesthesia. Micro Endoscopic Discectomy (MED) is two-stay surgery with a 16mm incision under general anesthesia. We will discuss the comparison, indication and outcomes between PELD and MED. [Objectives] Objects are to determine the indication and avoid repeating the unsuccessful cases. [Methodology] 669 cases of herniations (623 patients) were treated by PELD that were Transforaminal approach (374 cases), Interlaminar (199 for L5/S1), Extraforaminal approach (84 for lateral herniation) and 12cases of double lesions. 167 cases of herniation (158patients) were treated by MED. The indication of PELD was the herniation with migration less than 1 cm, central huge herniation, lateral herniation, and except combined with lateral recess less than 3mm at the portion of the pedicle. The indication of MED was the herniation with migration more than 1 cm, the herniation with lateral recess less than 3mm and osseous hypertrophy of spondylolysis, and the cases of narrow interlaminar space of L5/S1. The following are the results of the Visual Analogue Scale and Japanese Orthopedic Association scores. [Results] Average age was 48.417 years old in PELD and 54.1 15.6 in MED. Operation time was 5819 minutes in PELD and 12650 in MED. There was no significant difference between PELD and MED in terms of Sciatica, back pain and JOA score over a period of 6 month. Nearly 90% were satisfactory in the improvement rate of among the both. However, revisions of PELD were 75 cases 12% which were by 25 recurrences, 19 remnants, 11 cases of impossible due to insertion pain, 10 nerve adhesions, 2 instabilities and 2 lateral recesses which were mistaken preoperatively, and 6 others such as dura tear, mistook level, 2 bleedings or blood pressure decrease. 73% of PELD revisions were successful. 26 of them were MED under general anesthesia, 46 were PELD under local anesthesia, 2 were TLIF and one was open surgery. Finally, 94% of initial PELD operations were completed with excellent and good results. On the other hand, revisions of MED were 18cases 11%. All of MED revision cases were treated by the same method and were satisfactory in 62%. In the end, 90% of initial MED operations were completed with excellent and good results. [Conclusions] PELD is suitable for the majority of lumbar disc herniations. Its important to check pathological bone changes, the diameter of the interlaminar space and the foramen by 3D-CT before the operation. Be careful of damaging the ganglion. MED is suitable for the herniations with osseous problem and far-migration.