OBJECTIVETo summarize the mid-term effectiveness of Coflex non-fusion internal fixation treatment of degenerative lumbar disease.

METHODSFrom October 2008 to December 2010, a retrospective analysis was carried out on 39 patients (29 males and 10 females) diagnosed as degenerative lumbar disease and treated with Coflex interspinous dynamic device, who had been followed up for 1 year at least, the average age was 45.5 years (range, 23 - 67 years). The results were assessed by Japanese Orthopedic Association (JOA) scores, visual analogue scale (VAS) scores, Oswestry disability index (ODI) scores and SF-36 scores; and the range of mobility (ROM), intervertebral disc height of the responsible and adjacent segments were measured on X-film before the operation and at last follow-up. Observed the therapeutic effect of the patients and compared the effect on the patients of different body mass index (BMI) and different age by the One-way analysis of variance and paired t test.

RESULTSThe 39 patients were followed up for 30.9 months (range, 12 - 37 months). At the last follow-up, JOA, ODI, VAS and SF-36 scores were improved by 70% ± 12%, 54% ± 12%, 77% ± 10% and 51% ± 9%, and were statistically significant (t = -33.289, 26.448, 26.596 and -20.772, P = 0.00). Patients with BMI ≥ 25 kg/m(2) had lower improvement rates in the scores than those with BMI < 25 kg/m(2) (F = 10.561, 5.850, 5.651 and 6.519, P < 0.05). The patients were 50 years older or younger couldn't affected the improvement rates in the scores statistically (P > 0.05). There were no significant difference in remaining disc height (P > 0.05), except that the intervertebral disc height of L4-5 increased slightly compared with the preoperative (t = -2.819, P = 0.008). In addition to the ROM of L3-4, L5-S1 and L1-S1 were not significantly different from the preoperative(P > 0.05), the ROM of L4-5 were decreased (t = 12.598, P = 0.000).

CONCLUSIONSThe mid-term effectiveness of Coflex non-fusion interspinous fixation in treatment of degenerative lumbar disease is worthy of recognition, and Coflex combined with Isobar has advantages in the treatment of multi-segment degenerative lumbar disease.