Abstract

After a decade in clinical experience in percutaneous applications for intradiscal decompression since 1979 and endoscopic biportal technique since 1982, the idea to combine simultaneous endoscopic control with direct extradiscal tissue elaboration across an uniportal approach araised in the later eighties. Experiments with modified urologic workings-scopes designed for cystoscopic applications demonstrated in 1990, that endoscopic applications are possible also in non-preformed anatomical spaces when some hyperpressive irrigation was used for local atraumatic tissue spacing. So we introduced endoscopic coaxial foraminoscopy clinically for the first time in February 1991 for the treatment of a foraminal sequestrated herniation. A first publication on the early series was published in 1996. Since then the technology with improved endoscopic tools and irrigation systems as well as high-frequency cogulation under irrigation became almost standardized for this specific range of indication. The posterolateral approach from 9-12 cm from the midline follows the same criteria as for intradiscal applications, but the working cannula is directed to the foraminal sequestrum, which is extracted under endoscopic control then with a special working scope. Our first clinical series of 180 standardized cases brought successful primary results in 149 cases, including an initial definite learning courve. 24 patients needed later on conventional open surgery w/wo fusion. Here the initial results trend to "black or white": or the sequester is removed or not. Relatively freshly sequestrated fragments without local scar-adhesions are easier to remove. Anatomical limits can accour in L5/S1 when high iliac crests can impair flat approach to medioforaminally located sequestra. For preop evaluation a 3d- CT offering clear bony analysis of accessible trajectories can trace the access precisely. Detailed knowledge of foraminal anatomy is mandatory. Hospital stay could be reduced to 2 to 3 days, out-patient care is possible nowadays as well. Other pioneering authors as Destandau in France with his minimally-open endoscopically controlled technique for the posterolateral approach, and Ruetten from Germany with his original interlaminar approach completed further to the today wide range of well established endoscopic lumbar disc decompression techniques in trained hands.

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