Abstract
Purpose: We report on the midterm clinical results in a retrospective series of 157 patients who have undergone PLIF with the Varilift expandable and lordotic cages, mostly stand alone.
Material & methods: 157 consecutive patients, 80 men and 76 women, with a mean age of 44 (19 to 72); Single level procedure in 123 patients, 2 levels in 34 patients. Preoperative symptoms included chronic low back pain and/or sciatica for more than 6 months with failure of conservative treatment including epidural steroids. Primary surgical indications were degenerative disc disease (n = 76), spondylolisthesis (n = 33), failed back syndromes (n = 43 patients). Posterior fixation was added in 21 of the spondylolisthesis, 2 multi-level fusions and 3 other patients due to a previous wide laminectomies and a resultant instability. Surgical technique consisted of minimal bilateral laminotomy preserving the midline ligamentous structures and the conservation of most of the facets.
Results: Follow ranged from 12 to 60 months. There were a 89.2% satisfactory results, 10 fair and 7 poor results, of which 2 required revision. Neither revision was due to implant failure. Fusion was deemed solid in 150 from the 157 patients, 7 showed an asymtomatic radiolucency around the cage, but without motion on bending films. 3 other patients needed a posterior fixation removal after one year. Of the 128 patients working pre-op, post-op 92 patients returned to their previous job, 18 returned to a less strenuous position and 18 patients did not return to work. No patient’s symptoms worsened. As major complications, we noted 3 cases of foot drop who had partial (1) or complete recovery (2), and one cases of unilateral thrombosis of the retinum central artery. there were no cage breakage or migration of the implants.
Segmental lordosis, measured on the fused discs at the last follow up showed a mean angle of lordosis of 6.9o (4.8° on L4–L5, 8° on L5–S1).
Conclusion: The VariLiftTM Cage confirms by its medium term result the stand alone feature in the appropriate indications. This PLIF technique resulted in a greater than 90% fusion rate, with a minimal of complications, good pain relief, and early recovery. No failure of the material was noted. The major advantages of this device are its intrinsic stability, the big inner volume for bone graft, the promoting of lordosis and the overall size saving that authorize a minimal invasive procedure.
The abstracts were prepared by Orah Naor. Correspondence should be addressed to him at the Israel Orthopaedic Association, PO Box 7845, Haifa 31074, Israel.