Study design: Fifty-two patients with degenerative disc disease underwent single- or double-level anterior lumbar interbody fusion with SynCage and additional posterior fixation as treatment for degenerative disc disease and were prospectively followed for 4 years.
Objectives: To test the clinical performance of anterior lumbar interbody fusion with SynCage, with emphasis on the safety and efficacy of the surgical procedure and the ability to restore anatomy and fuse the motion segment.
Summary of background data: Anterior lumbar interbody fusion using femoral allograft and/or autologous bone has a high complication rate. With cage technology, some of these complications can be avoided. The design characteristics of the SynCage offer advantages in restoring and maintaining intervertebral height and restoration of lumbar lordosis.
Methods: Thirty-three patients underwent single-level and 19 patients double-level anterior lumbar interbody fusion with SynCage and additional posterior fixation (translaminar screws, n = 32 or pedicle screws, n = 10). Radiologic and functional results (VAS and Oswestry score) were evaluated.
Results: Intervertebral height was corrected from an average of 8.7 to 17.6 mm. Lordosis of the fused segment was significantly increased (average 10.6 degrees for the fused segment and 8 degrees for lumbosacral lordosis). After 2 years, there was radiologic evidence for fusion in 70 of 71 (98.6%) levels. Functional scores showed a significant improvement in pain and function up to the 2-year follow-up observation. At the 4-year follow-up observation, there was some loss of the initial improvement in VAS and Oswestry scores. Despite this loss, they remained significantly better than the preoperative scores.
Conclusions: Anterior lumbar interbody fusion with SynCage and additional posterior fixation is a safe and effective procedure. Intervertebral height is corrected, and lumbosacral lordosis is restored. An initial improvement in VAS and Oswestry scores is partly lost at the 4-year follow-up observation, but 4-year results are still significantly better than the preoperative scores.