INTRODUCTION: Recently various type of spinal instrumentation was applied, and they are thought to be essential in modern spinal fusion surgery. But several authors reported these applications might increase possibility of complication and accelerate degeneration on adjacent segment. PLIF is the best solution for degenerative conditions of lumbar spine, and basically this was introduced without any instrumentation.
METHODS: Twenty‐one cases of degenerative lumbar diseases were treated by PLIF with Brantigan carbon cages without spinal instrumentation. There were 8 males and 13 females, and age averaged 71.4 years. Sixteen cases were degenerative spondylolisthesis, four cases were spinal canal stenosis, and one was disc herniation. Single PLIF was performed on all the cases, with additional decompression on other segment in six. Bilateral facet joint were preserved to avoid lateral instability. Two pieces of Brantigan cage was inserted surrounded by local bone graft. All the cases went ambulatory on second post‐op. days, and soft brace was applied for three months. Post‐op. follow‐up period were 12 to 24 months, 15 months on average and clinical and fusion results were discussed.
RESULTS: JOA score (29 pts on full mark) averaged 13.0 pts before the operation and was 26.2 pts at the F/U. Recovery ratio averaged 82.5%. Clinical result was excellent in 14 and good in 7. Neither infection nor hematoma was identified. Nineteen cases showed solid bone union after one year, and two cases were classified as non‐union. Whereas early cage migration with vertebral collapse was seen on nine, and union with collapse was seen in eight. These conditions did not affect on clinical outcome.
DISCUSSION: Preserving facet joints, stand alone PLIF resulted in good clinical and fusion results with box type intervertebral cages. Further follow up is necessary for effect on adjacent segment degeneration. Stand alone PLIF is less invasive method and minimize chance of complication.