AbCs of oPErAtiVE tEChniquES

Dorn Spinal Therapy

Spine Healing Therapy

Get Instant Access

Arthroscopic or endoscopic spinal surgery via a posterolateral approach is performed through the triangular working zone located on the posterolateral annulus (5,23,24). Considering that the intervertebral disc is an amphiarthrosis when the surgery is being performed via an intradiscal approach, the term arthroscopic surgery is applicable. Some investigators have used the term endoscopic spinal surgery to describe the pos-terolateral approach to the contents of the spinal canal. However, note that the spinal canal is not a cavity, so the term extra-articular or periannular arthroscopic discectomy may be more appropriate.

Choice of Operating Room Table

The operating room table for arthroscopic spinal surgery must be radiolucent and relatively narrow so that the C-arm can be rotated from the anteroposterior (AP) to the lateral projection with minimal risk of contaminating the surgical field.

A pacemaker extension may be attached to the available operating room table and used for minimally invasive spinal surgery. A disadvantage of this arrangement is the

Ex;943 A54 OS/05/94 Ex:943 AS3 OS/06/94

Ex;943 A54 OS/05/94 Ex:943 AS3 OS/06/94

Fig. 8. (A) Preoperative axial MRI demonstrating sequestrated disc herniation at L4-L5; (B) sagittal MRI findings shown in (A); (C) postoperative axial MRI study shown in (A) demonstrating annular defect at site of disc herniation and evidence of fibrovascular invasion at site of extracted disc fragment; (D) sagittal view of findings shown in (C).

Fig. 8. (A) Preoperative axial MRI demonstrating sequestrated disc herniation at L4-L5; (B) sagittal MRI findings shown in (A); (C) postoperative axial MRI study shown in (A) demonstrating annular defect at site of disc herniation and evidence of fibrovascular invasion at site of extracted disc fragment; (D) sagittal view of findings shown in (C).

potential of inadvertently tilting the pacemaker extension and the table, particularly when an overweight patient is positioned for the surgery. In addition, the anesthesiologist may have difficulty reaching and monitoring the patient's status from the top of the table.

Fig. 8. (Continued)

Fracture tables have been used for minimally invasive spinal surgery. The extension of these tables used for positioning of the lower extremities is narrow and suitable for positioning the radiofrequency frame and the patient. This provides ample space for rotation of the C-arm intraoperatively. The AMSCO 3080 table appears to be the table of choice for arthroscopic spinal surgery. It is available in most operating rooms. This table has a long extension that is designed for positioning the lower extremities during surgery. During arthroscopic spinal surgery, we rotate the table and position the radiolucent frame and the patient's trunk and head on the distal end of the table. This allows free rotation of the C-arm around the patient. To further facilitate intraoperative movement of the C-arm, it is advisable to remove the foam mats from the top of the table and place the frame directly on the table.

Radiolucent Frame

Most arthroscopic spinal procedures are performed when the patient is in a prone position. This positioning becomes more critical when biportal access to the intervertebral disc is utilized. The available bolsters (US Medical, Paoli, PA) are comfortable and well padded. They provide ample room for the rib cage and adequate support for the patient's iliac crest and anterior superior iliac spine, thereby allowing reversal of lumbar lordosis (Fig. 9A), slight flexion of the hip joints, and widening of the dimensions of the foramen, so that the inserted instruments can be passed into the foramen and triangular working zone.

Prior to positioning of the patient, the bolsters of the frame should be adjusted to the size of the patient. The proximal ends of the bolster should be placed far enough apart to provide space for the patient's rib cage. In addition, the distal ends of the bolsters should be brought together so that they provide adequate support under the patient's iliac crest (Fig. 9B).

Was this article helpful?

0 0

Post a comment