Source: Spine & Peripheral Nerves Section 2001
During the past two and a half years, 25 patients with L5-S1 free fragments underwent outpatient endoscopic discectomies using a small, soft, malleable scope technique which is not traumatic to the spinal canal contents.
A skin puncture opening (less than 5 mm) is made; under local anesthesia with IV sedation, 1 cm off midline, for paramedian interlaminar access using a 4.2 mm outer cannula, with an inner telescoping fiber-optic working channel plastic endoscope, micro-dissectors and micro-graspers.
The 25 patients ranged in age from 29 to 61, 15 males and 10 females. All had free fragments in the spinal canal at L5-S1 ruptured lateral to the dura. Open microdiscectomy had already been recommended in all cases. All had radicular pain, numbness and/or weakness for at least six weeks consistent with the herniation. Results (Macnab criteria): 22 excellent (no symptoms, no restriction of activity) 2 good (occasional symptoms), 1 poor (no improvement, required further surgery); for an overall success rate of 96%. The only adverse effect was that one patient developed a transient, mild, localized hyperpathia which rapidly resolved.
This technique provides the advantage that the actual endoscope itself can be placed directly into the free fragment for optimal visualization and removal, in the most direct, least traumatic approach for reaching and removing free fragments at L5-S1.