Posterior dynamic stabiliziation as an alternative for instrumented fusion in the treatment of degenerative lumbar instability with spinal stenosis

Aim: Our retrospective study analyzed the outcome of patients with degenerative lumbar instability with spinal stenosis, who under-went decompression surgery with dorsoventral fusion (Group 1) and decompression surgery with posterior dynamic stabilization (Group 11). Method: For 10 patients in each group intra- and postoperative data were obtained and the functional outcome was evaluated with the "Oswestry Low Back Pain Disability Questionnaire" (OQ) and the "Short Form 36 Health Survey Questionnaire" (SF-36). The average follow up was 14.4 months in Group 1, 15.2 months in Group II. Results: In Group I the OQ averaged postoperatively 32 points (preoperatively 46 points), the "Physical Component Summary" (PCS) of SF-36 averaged 34 points (preoperatively 24 points), the "Mental Component Summary" (MCS) averaged 43 points (preoperatively 36). In Group 11 the values at follow up were as follows: OQ 33 points (preoperatively 54), PCS 34 points (preoperatively 28) and MCS 46 points (preoperatively 36). The average hospitalization was 28.4 days in Group 1, 19.3 days in Group 11 and the average operation time was 218 minutes in Group 1, 163 minutes in Group If. Conclusion: When compared the functional outcome, the dynamic stabilization seems to be a promising alternative to fusion in patients with degenerative lumbar instability with spinal stenosis.