MATERIAL and METHODS: Fifty patients with lumbar degenerative disease treated from August 2007 to September 2009 were included in this retrospective study. The Japanese Orthopedic Association (JOA) score and the Oswestry Disability Index (ODI) were used for therapeutic efficacy evaluation. Odom’s criteria were used to evaluate postoperative outcome with regard to symptoms. Anteroposterior X-rays were obtained after surgery. All patients were followed up for 2 years.

RESULTS: Based on Odom’s criteria, 22, 24 and 4 patients had excellent, good, and fair results respectively. The JOA score at 3, 12, and 24 months after surgery was significantly higher than before surgery (all p <0.001), and the ODI score at 3, 12, and 24 months after surgery was significantly lower than before surgery (all p <0.001). The posterior intervertebral disc height and the neural foramina height at 12 and 24 months after surgery was significantly higher than before surgery (both p <0.001).

CONCLUSION: Implantation of the second-generation Wallis interspinous dynamic stabilization device produced satisfactory clinical outcome at short- and medium-term follow-up in patients with lumbar degenerative disease. Keywords : Lumbar degenerative disease, Wallis interspinous implant, Postoperative outcome, Dynamic instrumentation, Lumbar interspinous spacer, Non-rigid fixation