Fusion was successful in three patients, two with an established pseudarthrosis.
The technique provides immediate three-column stabilization of the lumbosacral junction by means of a posterior approach, and the triangular construct potentially provides stability to the anterior column.
The technique is safe, effective, and employs instrumentation common to spine surgery. Its use in high-grade slips makes the technique more simple to perform than other methods of lumbosacral stabilization 1).
Many case-series studies of lumbosacral fusion for spondylolisthesis have been reported,
Twenty-five consecutive patients with mean age of 36.7 years underwent transdiscal fixation, and 31 other with mean age of 42.0 years to pedicle fixation were clinically and radiographically compared. Clinical assessments were performed using Oswestry Disability Index (ODI), Core Outcomes Measures Index (COMI), Short-Form 12 (SF-12), and pain visual analog scale (VAS). Radiographic spinopelvic parameters were also evaluated. The mean follow-up was 2.7 years (range 2.0-5.3).
Preoperative data were comparable between groups. Surgery time, blood loss, and hospital stay were similar between groups. At last follow-up, clinical and radiographic outcomes were significantly improved in both groups. Postoperatively, both lumbar and leg pain VAS were similar between groups, but ODI (20.2 vs. 31.6, p = 0.010), COMI (1.6 vs. 2.8, p = 0.012), and SF-12 physical (84.3 vs. 61.5, p = 0.004) and mental (81.5 vs. 69.4, p = 0.021) scores were significantly better in the transdiscal group. The neurologic complication rate was similar in both groups. There were 4 pseudoarthroses in the pedicle group, and none in the transdiscal group. : L5-S1 transdiscal screw fixation provided better functional and radiographic outcomes at medium-term than conventional pedicle fixation for high-grade spondylolisthesis, although transdiscal sacral screws are difficult to place in correct position 11).
Chell et al. report on a consecutive series of three adult patients with high-grade slippage who were treated with transvertebral pedicle fixation and standard spinal instrumentation, as both primary and revision procedures. There were no complications from the procedure, and a good outcome was achieved in all patients. The results at 4- to 8-year follow-up review are presented. This is a relatively simple and safe method of achieving spinal stabilization, which bypasses some of the problems caused by the associated anatomical distortion in high-grade spondylolisthesis and has good results at midterm follow up 12).