Symptomatic, single-level degenerative disk disease in the lumbar spine (L3-S1) in skeletally mature patients with no more than grade I spondylolisthesis at the involved level and who have failed nonsurgical treatments for at least 6 months.

Figure 35-1, A and B show flexion/extension lateral radiographs showing disk height loss and degeneration at L5-S1. Note the absence of instability.

Use T2 weighted-sagittal magnetic resonance imaging (MRI) to document disk degeneration (Figure 35-2).

Use axial MRI images to assess significant facet joint degeneration, which would be a contraindication for arthroplasty.

Perform preoperative DEXA scan to verify adequate bone density (T-score greater than −1.0) before the procedure.

Figure 35-3 is a computed tomography (CT) diskogram showing morphologic changes at L5-S1; the patient reported 10/10 concordant pain. The L4-5 level was normal with minimal discomfort.

During anterior exposure at the L5-S1 level, the disk space is found between the left and right iliac veins (Figure 35-4).

For L3-4 and L4-5 procedures, the vessels should be dissected off the anterior spine and retracted to the right to expose the spine (Figure 35-5).

The patient is positioned supine on a regular operating table with arms padded at the elbow and taped across the chest.

The anterior approach to the lumbar spine is used through either a transverse or horizontal incision.

The rectus fascia is incised in line with the skin incision, and the midline fascial raphe of the rectus is identified.

The retroperitoneal dissection starts on the medial border of the rectus and proceeds lateral and posterior to the muscle belly, having less potential chance of denervation of the rectus.

The plane is bluntly dissected superficial to the abdominal contents along the left abdominal wall outside the peritoneum and taken posteriorly toward the psoas muscle (Figure 35-6).

The entire peritoneal sac (with the ureter) can be bluntly dissected off the abdominal wall and retracted toward the midline with a handheld retractor.

Insertion of a screw or bent needle into the disk space should be done to verify the level and verify the midline of the disk space with fluoroscopic imaging (mark the position on the anterior spine with Bovie cautery before removing marker).