Clinical outcome of single-cage combined with short-segment pedicle instrumentation for lumbar spine instability

English Keywords:Instability of lumbar vertebrae  Short segment  Cage  Pedicle screw  Clinical efficacy

English Abstract:

  【Abstract】 Objective：To evaluate the clinical efficacy of single-cage combined with short-segment pedicle instrumentation for lumbar spine unstability.Method：149 consecutive cases with lumbar spine instability from March 1999 to August 2007 undergoing the above treatment were reviewed retrospectively.Among these cases，there were 83 males and 66 females，with the average age of 46.7 years-old（range，32-68 years old），definite instability was determined at L3/4 in 7 cases，L4/5 in 50 cases and L5/S1 in 92 cases.NaKai criterion was used to determine postoperative clinical effect.All cases were followed up to notify the vertebral and instrument displacement.The ratio of the height of instability intervertebral space and their adjacent cranial space at 1 week and 16 months after operation were measured respectively.Result：The operating time was 1.5-3 hours （average，1.8 hours），with blood loss approximately of 200-600ml（average，490ml）.4 cases were complicated neurological deficit and 5 cases had dural tear.The average follow-up time was 39 months（range，16 months to 81 months）.The lumbar spine alignment returned to normal after operation.There was significant difference with respect to intervertebral space height between preoperative and 1 week after operation（P<0.05），while no significant difference were noted between 1 week and 16 months after operation（P>0.05）.According to NaKai criterion，at 16th month after operation，115 cases were classified as excellent，good in 26 cases and fair in 8 cases with the excellent and good rate of 94.5%.According to Suk criterion，the fusion rate was 100% at 16th months after operation with no recurrence of instrument failure at final follow-up.Conclusion：Single-cage combined with short-segment pedicle instrumentation for lumbar spine instability is a safe and reliable，which can maintain the intervertebral disc height and stabilization as well.