Treatment Concept and Technical Considerations of Biportal Endoscopic Spine Surgery for Lumbar Spinal Stenosis.

Decompression must be a major composure of surgical procedures for degenerative lumbar spinal stenosis. In addition to sufficient decompression for guarantee of relieving neurologic pain, compensating surgical instability after wider laminectomy and foraminotomy, and instrumentation with caging and fusion with grafting are performed for securing or restoring foraminal dimension, and correcting coronal/sagittal imbalance for expecting longer survival of adjacent segment. Endoscopic spinal surgery (ESS), full-endoscopic or biportal-, has been developed under a flag of successful decompression with preserving structural integrity as much as possible in helps of magnification and illumination, and gives a technical possibility and feasibility to solve LSS by decompression-alone. There come, recently, lots of endoscopic trials for overcoming conventional surgical treatment in need of wider dissection and escaping inevitable complications from surgical damage and compensating fusion technique. However, biportal-ESS till a recent era has been showing some technical limitations including clinical difficulties in accessibility for more moderate to severe stenosis and challenges for complicated conditions with segmental ventral slip, isthmic defect, stenosis combined with foraminal stenosis or foraminal disc rupture, or degenerative segmental scoliosis with disc height collapsing and endplate fatigue fracture. Because decompression-alone, itself, is just a skill for eliminating pathologies, and no protentional function of preserving degenerative structure young forever or stopping recurrency of disc degeneration or creeping subsidence foramen. The purpose of this review on clinical reports is to suggest potential possibility of Biportal-ESS for treating degenerative lumbar disorders by sufficient decompression, adequate elimination of various pathologies, and decreasing technical complications in deep considering of skillful tricks and trades, and in hope of being a basic skill for developing better innovative spinal surgical techniques in near future.