Clinical outcomes of B-Twin expandable intervertebral cage in the treatment of lumbar spinal instability syndrome

English Keywords:Lumbar  Intervertebral cage  Spinal fusion  Lumbar spinal instability syndrome

English Abstract:

  【Abstract】 Objective：To investigate the clinical outcomes of B-Twin expandable intervertebral cage in the treatment of lumbar spinal instability．Method：From March 2006 to June 2009，a total of 56 disks in 52 patients with degenerative lumbar spinal instability underwent PLIF operation using B-Twin intervertebral cage．The JOA score，intervertebral height and fusion status for all cases pre- and post-operatively were reviewed retrospectively．Result：All cases were followed up for an average of 12 months（range，8-18 months），the mean preoperative JOA score of 52 cases was 7（range，5-9），while 19 （range，15-22） at 1 week postoperatively and 22（range，19-26）at final follow-up，which showed significant difference（P<0.01）．Clinical outcomes were excellent in 36 cases，good in 12 cases and no effect in 4 cases，with the excellent rate of 69.3%．The preoperative intervertebral height was 8.0mm on average（range，7.5-11mm），while 11.5mm （range，9.5～13mm ）at 1 week postoperatively and 11mm （range，9.0～12.5mm ）at final follow-up，which showed significant difference（P<0.01）．The fusion rate was 78.6% on dynamic radiograph，and the B-twin subsidence rate was 21.2%，and no B-twin displacement was noted．Conclusion:The short-term outcomes of B-twin for lumbar spinal instability is reliable，but prosthesis subsidence and low back stiff should be taken into account.