(surgical technique and outcome in 480 cases)
Tungs’ Taichung MetroHarbor Hospital, Taiwan
In order to decrease surgical morbidity, surgeons have attempted to minimize surgical trauma by using small incisions and microscopes for magnification. Percutaneous endoscopic lumbar spine surgery has opened a new window of opportunity in the treatment of lumbar disc disorders. This paper report our surgical technique,outcome and complications of this method in 480 casas.
Materials & Methods:
From June 1998 to June 2005, there were 480 cases including in this study. The individual diagnosis were 402 cases with contain & noncontain HIVD syndrome, 17 cases with far lateral discs, 15 cases with recurrent discs, 10 cases with infective spondylodiscitis, 24 cases with foraminoplasty, and 10 cases with lateral recess stenosis. In dealing with these conditions, emphasis was placed on visualizing spinal structures and targeting the removal of pathologic disc tissue. Pre-operative discogram was performed in each case for diagnosis the disc condition. The surgical technique is using percutaneous YESS endoscope spinal surgery method with the patient in prone position under local anesthesia. Expect 18 cases received general anesthesia. Most cases were performed by posteriorlateral approach and interlaminal approach was applied in L5S1 paramedium disc or some migrated disc. The average operative time is 30 minutes( range 20-110 min).
We use modified MacNab criteria to evaluate the results. The average follow up time is 35 months with range 12 months to 66 months. In the first three years, less than 80% of pts reported good/excellent results; however, since 2002, 90% of the pts reported G/E results in the contain & noncontain disc group. 82% and 80% satisfactory rate was reported in far lateral disc and recurrent discs individually. The satifactory rate in spinal infection , lateral recess stenosis and foraminoplasty cases reported around 70%. Complications include 14 cases dysesthsia, 1 case minor CSF leakage, 8 case discitis, 3 forceps broken, one case with motor impairment and no major vessels injury.
Visualized endoscopic spinal probing with the pt in the aware state may help close the diagnostic gap, and allow the surgeon to consider a wider spectrum of therapeutic options. The successful rate increased after changing inside out technique to target fragmentectomy. Recurrent and far lateral discs are good indication for this technique. Using this technique will also led to identification the new pathology of the spine (discogenic pain, fail back syndrome). Clear visualization and proper cannula placement are very important point for success and avoiding complications. The initial learning curve may be the reason of increasing the complication rate that can discourage surgeons who are more comfortable with a familiar procedure. Pre-op antibiotics and high volume irrigation can avoid septic discitis. Like endoscopic knee surgery in the beginning, endoscopic spinal surgery need more learning curve, new technique & equipment to assist its development. The future of minimally invasive spine surgery will incorporate the concepts of tissue healing, tissue modulation; inject able nucleus, and prosthetic disc replacement.