Cervical Laminoforaminotomy with Working Channel Endoscope

47 Cervical Laminoforaminotomy with Working Channel Endoscope


Gun Choi and Akarawit Asawasaksakul


47.1 Introduction


Posterior cervical foraminotomy has been applied extensively in the management of unilateral cervical radiculopathies, either due to a foraminal disk or due to bony spurs projecting into the foramen.1 Keyhole laminoforaminotomy with the use of an operating microscope has limited morbidity of the paraspinal soft tissue and enhanced safety of the neural structures.1,2,3 Sequential dilator systems like the METRx have also reduced intraoperative bleeding and surgical times. The results are equivalent between open and minimally invasive approaches.3,4,5,6,7 To further benefit the patient in terms of the most minimally invasive approach possible, we have combined keyhole surgery with a working channel endoscope (Video 47.1).


47.2 Surgical Technique


47.2.1 Position and Anesthesia


• The patient is placed in the prone position and general anesthesia is preferred (Fig. 47.1).


• The patient is positioned on a radiolucent table with the neck in either neutral or slight flexion to facilitate interlaminar approach and drilling.


• Shoulders need to be strapped and pulled caudally to allow visualization of lower cervical levels on lateral view fluoroscopy.


• Level marking is done before scrubbing/draping to facilitate changes in position if needed.


47.2.2 Needle Insertion


• The target point for the needle tip is the V point of the cranial lamina on the symptomatic side—i.e., the lateral-most part of the lamina approximately correlating with the location of the pedicles (Fig. 47.2).


• It is always safe to target the needle toward the inferior margin of the cranial lamina, because in the cervical spine the laminae are significantly overlapped and targeting the caudal lamina may result in inadvertent entry of the needle into the interlaminar space toward the spinal cord.


• An 18 G 90-mm spinal needle is directed toward the target point under lateral view fluoroscopy (Fig. 47.3).


• Inclination of the needle trajectory is highly variable depending on the level, but the needle should be perpendicular to the lamina, in the mediolateral plane, and slightly cranial to caudal.


• The needle advancement is stopped when the bone is encountered and the needle is replaced with a 0.9-mm guidewire.





47.2.3 Instrument Placement


• A 1-cm skin incision allows passage of sequential dilators over the guidewire (Fig. 47.4).


• It is essential to ensure that the serial dilators are held securely against the lamina to make sure that no soft tissue obliterates the endoscopic view.


• Serial dilators avoid the need for soft tissue dissection by pushing the tissue away, resulting in reduced postoperative pain and bleeding.


• The dilators are followed by the passage of a 7.5-mm round working cannula, which accommodates the working channel endoscope, and continuous-pressure cold irrigation with antibiotic-instilled normal saline (Fig. 47.5).





Stay updated, free articles. Join our Telegram channel

Mar 29, 2020 | Posted by in ORTHOPEDIC | Comments Off on Cervical Laminoforaminotomy with Working Channel Endoscope

Full access? Get Clinical Tree

Get Clinical Tree app for offline access