Experience with the second-generation Wallis interspinous dynamic stabilization device implanted in degenerative lumbar disease: a case series of 50 patients.

AIM: This study aimed to evaluate the short- to medium-term outcomes of the second-generation Wallis interspinous dynamic stabilization device for treatment of lumbar degenerative disease. 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.

[Unilateral pedicle screw fixation and transforaminal lumbar interbody fusion through paraspinal muscle approach for recurrent lumbar disc herniation combined with lumbar instability].

OBJECTIVE: To explore the clinical effects of unilateral pedicle screw fixation and transforaminal lumbar interbody fusion (TLIF) through paraspinal muscle approach for recurrent lumbar disc herniation combined with lumbar instability. METHODS: A total of 35 patients with recurrent lumbar disc herniation combined with lumbar instability were treated between March 2008 and May 2010, including 15 patients managed by the paraspinal muscle approach with unilateral pedicle screw fixation and transforaminal lumbar interbody fusion (TLIF) (unilateral fixation group) and 20 patients by the posterior midline approach with bilateral pedicle screw fixation and posterior lumbar interbody fusion (bilateral fixation group). Operation time and intraoperative blood loss were observed, preoperative and postoperative JOA score and VAS score in low back pain and legs pain, the interbody fusion condition were compared between two groups. RESULTS: All patients were followed up from 6 to 30 months with an average 16.8 months. All clinical symptoms had obviously improved postoperatively. X-rays showed good interbody fusion (only 1 case did not obtain fusion in bilateral fixation group) without cage displacement or settlement and implant loosening or breakage. There was significant difference in operation time and the intraoperative blood loss between two groups (P < 0.05). Postoperative JOA score had obviously decreased than preoperative one (P < 0.05). At 1 week after surgery, there was significant difference in VAS score of low back pain between two groups and there was no significant difference in VAS score of legs pain between two groups (P > 0.05); at final follow-up, there was no significant difference in VAS score of low back pain and legs pain between two groups (P > 0.05). CONCLUSION: Two methods both can obtain satisfactory effect in treating recurrent lumbar disc herniation combined with lumbar instability. Through the paraspinal muscle approach with unilateral pedicle screw fixation and TLIF has advantages of smaller surgical incision, shorter operation time, less intraoperative blood loss, faster relief in low back pain after operation, etc.

[Clinical analysis of an interspinous stabilization system (wallis) in treating lumbar degenerative disease].

OBJECTIVE: To evaluate clinical results of an interspinous stabilization system (Wallis) in treating lumbar degenerative disease in the short-term. METHODS: From August 2007 to June 2010,48 patients with lumbar degenerative disease who were treated with interspinous stabilization system, the data of patients were analyzed retrospectively. In all of the 48 cases, there were 30 males and 18 females with an average age of 54.2 years (ranged, 40 to 68 years). Forty-four cases were with single segment and 4 cases with two segments. Of them, 4 cases were in L3, 4, 40 cases were in L4, 5, 4 cases were in L3, 4 and L4, 5. The radiographic data of patients were analyzed. Clinical effects were evaluated by Japanese Orthopedic Association (JOA) score system and low back pain disability questionnaire (Oswestry) and Odom method. RESULTS: All the patients were followed up from 1 to 2 years with an average of 18 months. According to Odom's criteria, 20 cases obtained excellent results, 24 good, 4 fair. JOA score increased from 12.4 +/- 2.7 preoperatively to 26.1 +/- 2.0 postoperatively (P < 0.01). Oswestry score decreased from 14.1 +/- 2.9 preoperatively to 5.5 +/- 1.8 postoperatively (P < 0.01). The posterior height of intervertebral space and height of nerve root canal increased compared with that of preperative height. CONCLUSION: The treatment of lumbar degenerative disease with interspinous stabilization system can obtain satisfactory effects in the near future. It can retain dynamic stable of corresponding segments, expand volume of vertebral canal, and is safe and feasible.