The Treatment Of Highly Migtated Lumbar Disc Herniation By Percutaneous Endoscopic Lumbar Discectomy

Background and Objectives: Surgery plays a very important role inthe treatment of Lumbar disc herniation(LDH)， which was usually treatedby open surgery in the past. Percutaneous endoscopic lumbardiscectomy(PELD) has been a primary surgical procedure to deal withlumber disc herniation since Kambin raised the concept of Kambin Triangleand accomplished the first endoscopic disc procedure according to theconcept in1973. This surgery is effective and minimally invasive, with aeffective rate of90%which is close to traditional open surgery. On the otherhand, as it’s difficult for the PELD to decompress pinched nerve root thoughthe affected side intervertebral foramen, highly migrated herniatedintervertebral disc(HIVD) has long been a challenge for PELD, whichpromoted the formation of three common operative approaches ofPELD(transforaminal approach, contralateral transforaminal approach,interlaminar approach) with the development of surgical instruments and techniques. In addition, the application of new instruments promoted thedevelopment of new operation technique such as foraminoplasty. Thepurpose of this study was to discuss the percutaneous endoscopic treatmentof highly migrated intracanal disc herniation.Methods: In our retrospective analysis, between March2011andMarch2013, a PELD was performed in73patients to treat single segmenthighly migrated disc herniation. Record data such as operation time andradiograph times of the three operative approaches. The outcomes wereevaluated with the visual analogue score(VAS)，oswestry disability index（ODI） and the modified MacNab criteria.Results: Contralateral transforaminal approach took the longestoperation time and the most times of radiograph, interlaminar approach tookthe shortest operation time and the lest times of radiograph. Follow-up wasapplied to all of the73patients, among which VAS score and ODI decreaseddramatically no matter which of the tree operative approaches had beenapplied.3months after surgery, the total success rate was90.4%accordingto the modified MacNab criteria. There was no statistical difference betweenthe tree operative routes.Conclusion: PELD is effectively to treat highly migrated discherniation no matter which operative approach of the three is employed.Transforaminal approach is more appropriate in a herniation of L4/5andabove, intervertebral foraminoplasty is more appropriate in a migrated herniation or a herniation with a tiny pedicle which is difficult to find.Contralateral transforaminal approach is more appropriate in a L3/4or L4/5herniation close to middle line, as well as a herniation with a narrow affectedintervetevral foramen. Interlaminar approach is more appropriate in a L4/5、L5/S1central type herniation.