(surgical technique and outcome in 480 cases)

  Shao-Keh Hsu

  Tungs’ Taichung MetroHarbor Hospital, Taiwan

  Introduction:

  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).

  Results:

  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.

  Discussion:

  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.