Treatment Of Degenerative Disc Disease With Coflex Interspinous Implant Or Posterior Lumbar Interbody Fusion: A Prospective Comparative Study

Objective:1. To study the clinical effects of single Coflex interspinous implant on the treatment of degenerative disc disease (DDD).2. To explore the clinical effects of Coflex interspinous implant on adjacent segments upper fusion in the treatment of DDD.Methods:1. Firstly, the entry and removal value were made, then we selected patients who were treated with single Coflex interspinous implant (Coflex group) or Posterior lumbar intervertebral fusion (PLIF group) from June 2008 to June 2009. The hospital stay, operative time, blood loss and complications of all cases were surveyed. Low back pain (LBP) and leg pain at preoperative and final follow-up were evaluated according to VAS scales, and the Oswestry Disability Index (ODI) was recorded to evaluate the function. Flexion-extension radiographs were taken separately and Range of motion (ROM) of the instrumented level and upper adjacent were measured. We compared the hospital stay, operative time, blood loss between groups. At the same time, VAS scales of LBP and leg pain, ODI, ROM of the instrumented level and upper adjacent were also compared in and between groups.2. The entry and removal value were firstly made, then we collected patients who were treated with Coflex interspinous implant on adjacent segment upper fusion (Coflex combined fusion group) or double segments of PLIF (double fusions group) from June 2008 to June 2009. The hospital stay, operative time, blood loss and complications of all cases were surveyed. Low back pain and leg pain at preoperative and final follow-up were evaluated according to VAS scales, and ODI was recorded to evaluate the function. Flexion-extension radiographs were taken separately and ROM of segment of operation and upper adjacent were measured. We compared the hospital stay, operative time, blood loss between groups. At the same time, VAS scales of LBP and leg pain, ODI, ROM of segment of operation and upper adjacent were also compared in and between groups. Results:1. There were 21 patients in the group of Coflex and 71 cases in group of PLIF, and no significant difference was showed in age, gender, disease or surgical site between groups. Hospital stay, operative time and blood loss in the Coflex group were significantly less than in the group of PLIF(P<0.01). VAS scales of LBP and leg pain, ODI of the final follow-up were significantly lower than preoperative in both groups (P<0.01). Between groups, however, there were no significant differences neither at preoperative or final follow-up (P>0.05). It achieved bone fusion in the group of PLIF at the final follow-up, although ROM of the instrumented level at the final follow-up in the group of Coflex was similar to the preoperative (P=0.70). It was significantly higher in terms of ROM of the instrumented level at the final follow-up in the group of Coflex (P<0.01), but no significant differences were found in terms of ROM at preoperative between groups (P=0.50). ROM at the upper adjacent level at the final follow-up in the group of Coflex was similar to the preoperative (P=0.63), whereas that in group of PLIF was markedly increased at the final follow-up (P=0.02), compared with preoperative. It was significantly higher in terms of ROM of segment of adjacent upper operation at the final follow-up in the group of PLIF (P=0.02), though no significant differences were found in terms of ROM at preoperative between groups (P=0.61)2. There were 12 patients in the group of Coflex combined fusion and 11 cases in group of double fusions, and no significant difference was showed in age, gender, disease or surgical site between groups. No differences were found in hospital stay (P=0.21) or operative time (P=0.24) between groups, but blood loss in the group of double fusions was more than that of group of Coflex combined fusion (P=0.03). VAS scales of LBP and leg pain, ODI of the final follow-up were significantly lower than preoperative in both groups (P<0.01). Between groups, however, there were no significant differences neither at preoperative or final follow-up (P>0.05). All the segments filled with cages achieved bone fusion at the final follow-up, and the ROM of them reduced significantly (P<0.01), compared with preoperative. ROM of segments implanted Coflex was reduce (p=0.04), although significant higher than the segments filled with cages (P<0.01). ROM of segment of adjacent upper operation at the final follow-up in the group of Coflex combined fusion has no change (P=0.20), and on the contrary that in the group of double fusions was markedly increased at the final follow-up (P<0.01), compared with preoperative. It was significantly higher in terms of ROM of segment of adjacent upper operation at the final follow-up in the group of double fusions (P<0.01), but no significant differences were found in terms of ROM at preoperative between groups (P=0.20).Conclusion:1.There is no significant differences between single Coflex interspinous implant treated for DDD and posterior interbody fusion in improving clinical symptoms. But hospital stay, operative time, blood loss were less in the single Coflex interspinous implant groups than those in posterior interbody fusion groups.2. Compared with the group of double segments of PLIF, the blood loss in the group of Coflex interspinous implant used on adjacent segments upper fusion is less, although there is no difference in efficacy in improving clinical symptoms between the two groups.3. Coflex interspinous implant not only provides control but not limited activity of the surgery segment, but also effectively reduces the activity of the adjacent segment.