ENDOSCOPIC TREATMENT OF LUMBAR DISC PROLAPSE
Now a day every speciality is going for minimally invasive technique.
When we started our Neurosurgical training in 1989 the concept was adequate wide exposure of the pathology - to ensure minimal retraction of the tissue and to minimize the damage to the tissues. Now the concept is Key-Hole Surgery with the help of Neuro-endoscopic illumination and magnification. Surgeries like aqueductoplasty and third ventriculostomy were never thought of with much less morbidity. Most patients are reluctant to undergo disc surgery because of the fear of weakness, post operative pain, long immobilization etc. Now we are providing Endoscopic Treatment for Lumbar Disc Prolapse, Lumbar Canal Stenosis, Cervical Disc Prolapse, along with Neuroendoscopic treatment for pitutary tumours, hydrocephalus, intracerebral clots, etc. The endoscopic discectomy procedure used by us is that advocated by Dr. Jean Destandau M.D., an eminent Neurosurgeon from France - the pioneer of this technique - with his own designed instruments.
Standard surgical technique is the posterior approach discectomy. The use of an endoscope allows the same access port and same surgical technique to be used on vertebral canal and disc while at the same time reducing the skin incision. The advantages of this technique are the same as those for discectomy but the immediate postoperative effects are reduced allowing a more rapid rehabilitation and return to previous activities. Reduced size of incision also represents an aesthetic advantage.
Endoscopic microdiscectomy can be carried out under local, peridural or general anaesthesia. The patient is placed in the knee-chest position,withmaximum elevation of the area concerned. If necessary,the operating table can be inclined.
DETERMINATION OF THE POINT OF INCISION
By means of a special localization device the point of incision and the direction of approach is determined under fluoroscopic control.
SKIN INCISION AND APPROACH
At the marked point, a 15-20 mm skin incision is made. The aponeurosis is incised using scissors. The underlying paravertebral muscles are retracted laterally and any bleeding is coagulated. A 12 mm bone chisel is inserted until contact with the posterior vertebral arc is made.
DILATION OF SOFT TISSUE WITH THE ENDOSPINE OPERATING TUBE
The ENDOSPINE operating tube with its obturator is pushed through the incision in the direction of the posterior arc, after which the obturator is removed. Any soft tissue that bulges into the operating cone may be removed using a rongeur.
PREPARING THE WORKING INSERT
The devise ENDOSPINE has three access ports, one for the endoscope
(4 mm. in dia), another for suction cannula (4 mm. in dia.) and the largest for surgical instruments (9 mm. in dia.) The first two are parallel and the third is at an angle of 12 degrees with the tubes converging in the plane of posterior longitudinal ligament. The angulation enables the surgeon to keep the distal ends of instruments in view at all times and to use the suction cannula as second dissecting instrument. The endospine also includes a nerve root retractor that can be used to retract the nerve root medially.
This involves resection of part of the superior lamina and part of the intervertebral articulation, with exposure of the dural sac and nerve root. Resecting the bone enables easier access to the herniated disk without any traction on the nerve root, ensuring integrity of other nerve roots that might adhere to the main root.
RESECTING THE YELLOW LIGAMENT
Resecting the bone allows access to the superior insertion of the yellow ligament. This insertion is also resected using the 90oKERRISON punch.
DISSECTION OF THE NERVE ROOT AND RESECTION OF THE HERNIATED DISC
Once the nerve root has been accurately identified, it is dissected using a nerve retractor. The epidural veins may be coagulated if necessary with bipolar cautery. Using the integrated nerve retractor, the nerve root can be pushed medially, allowing access to the herniated disc without any danger to the neural structures. Depending on local findings, microdiscectomy involving the extraction of the easily mobilized parts of the nucleus pulposus can be carried out.
WHY THIS ENDOSCOPIC PROCEDURE ?
This endoscopic procedure allows adequate removal of lamina and if necessary medial part of facet, which allows good and adequate root decompression. For canal stenosis adequate decompression is possible. Migrated, extruded and herniated discs, old sclerotic discs are also comfortably excised with this procedure because of medial, lateral, cranial and caudal maneuverability of the endoscopic system. L4-5 and L5-S1 discs can be removed through a single 15-20 mm. incision because of the angulation of sacrum.
- Minimal skin in incision
- Internal view of operating site
- Reduced postoperative effects-less painful for patient
- Minimally invasive technique
- More rapid resumption of patients previous activities
- Patient is mobilized on the same day
- No blood transfusion required