Lumbar spinal stenosis is a common cause of radicular and generalized back pain among older adults. Endoscopic minimally invasive surgery, in contrast to open decompression, may provide the opportunity for a less invasive surgical intervention. Visualization and illumination during the operation can be optimized. Since a more extensive bone or ligament resection is frequently necessary here, a larger diameter endoscope with a correspondingly larger endoscopic working channel and larger instruments and burrs are necessary. After the access has been created, the bony structures are exposed. It may be helpful to start decompression at the caudal end of the descending facet. Depending on the pathology, decompression is then commenced with resection of parts of the medial descending facet, the cranial and caudal lamina, and the ligamentum flavum. The extent of decompression generally continues cranially at least until the tip of the ascending facet and caudally to half of the pedicle. The medial portions of the ascending facet and the ligamentum flavum are then resected until sufficient decompression of the neural structures can be clearly seen. In the case of a central stenosis, the ligamentum flavum generally needs to be resected medially to the midline. If the patient experiences bilateral symptoms of stenosis, an “over the top” access using the undercutting technique to the opposite side is carried out.
Endoscopic Dorsal Ramus Rhizotomy is a procedure that can provide patients with relief of pain associated with degenerative disease of the facet joints. Use of the spine endoscope provides visualization of the posterior spinal anatomy and nerves, while an endoscopic RF probe facilitates the ablation of the medial (and lateral) branches of the dorsal ramus and can lead to more complete ablation of the nerves and therefore better and longer lasting pain relief. Endoscopic Rhizotomy is most effective in those patients who have experienced greater than 50% relief of pain with medial branch blocks. The Endoscopic Dorsal Ramus Rhizotomy procedure offers an alternative for addressing axial back pain that is much less invasive than spinal fusion. A Rhizotomy is primarily done at the junction where the medial branch of the dorsal ramus nerve crosses over the transverse process of the vertebral body, however to make sure a complete ablation is accomplished rotating the RF probe through a full 360˚ ensures a complete evulsion of the nerves is achieved.
Patient selection is critical to the success of any surgical approach, the herniated disc tissue must be accessible through the foramen. Patient is positioned in the prone position on either bolsters or a Wilson frame to open up the foraminal space. AP and Lateral radiographs are used to identify the targeted foraminal levels. If an intra-discal approach is elected, an 18 gauge spinal needle is initially introduced not past the medial edge of the pedicle AP view, and in the posterior 3rd of the disc space in the lateral view with care being taken to avoid the exiting nerve root. The guide wire is transferred through the needle and a stab incision is performed along the guide wire. The dilator is introduced over the guide wire to the level of the annulus, again care should be taken to avoid the exiting nerve. The beveled cannula is introduced over the dilator creating a working portal for the introduction of the endoscope for direct visualization, light, irrigation and working access to the previously identified pathology. Upon completion of the surgery, the small wound can be closed with either steri-strips or a single stitch.
The interlaminar window at L5-S1 is easily accessed through a direct posterior approach, visualized using both AP and Lateral radiographs. The lateral facet is located and the stab incision is made directly medial to the facet to the level of the fascial layer. The dilator is introduced to the level of the ligamentum flavum, confirming AP and Lateral radiographs. The cannula is introduced over the dilator with the bevel open medially and the endoscope is introduced. Various instruments including the Trigger-Flex® RF probe are used to expose the ligamentum flavum. Punches and kerrisons can now be used to perforate the ligamentum for access to the spinal canal. The nerves are visualized and mobilized using a dissector. The canula is rotated to further mobilize, retract and protect the nerves exposing the herniation. A variety of instruments along with the Trigger-Flex® RF probe can now be utilized to remove disc material. The small wound site can be closed with minimal suture or steri-strips.
“An important consideration for anyone doing endoscopic surgery is how to ablate tissue and create hemostasis. Not all methods are created equal and I have found over the last 15 plus years that elliquence’s technology is trustworthy and performs better than other RF machines, allowing me to achieve better results. elliquence technology cleanly and efficiently ablates the tissue while controlling hemostasis very effectively, and as a result is a key component in excellent patient outcomes.”
I just wanted to send along our team’s sincere thanks for all of the help elliquence has provided during the recent separation of the Aguirre twins. In each of the procedures, the elliquence Radiowave Energy Source, both bipolar and monopolar system were used. Recognizing that we would need an energy source that would cut and coagulate without generating extra heat and burn was key to our separation efforts of the conjoined brains. As we came to the end of the final separation, it became clear that they boys brains were actually fused. At this point the elliquence technology became key in splitting the conjoined brains with as little injury as possible and so far that has clinically proven to be the case. Both boys are doing very well with no evidence of any neurological deficit. Your resources were invaluable and very much appreciated – many thanks from the boys and the CHAM team. You will also be interested to know that the Surgi-Max Dual Frequency unit has now become our exclusive unit of use in the craniofacial procedures and spinal dysraphism cases. The minimal production of burn and heat has made this unit invaluable to our service. The ability to gently shave off a lipoma in a lipomyelomeningocele, without injury to the underlying conus secondary to thermal heat, has made this unit a remarkable addition to our surgical armamentarium – keep up the great design work.