Predictors for a negative surgical outcome in patients with disc degenerative disease (DDD)

Abstract: Aim The aim of this study was to identify predictive factors for negative treatment outcome defined as high disability ratings in patients undergoing spine surgery for disc degenerative disease (DDD) Method Patients were consecutively recruited from a waiting list for surgery at Stockholm Spine Center. The analysed cohort consisted of 212 patients (109 women and 103 men, 25-65 years old). They all had radiologically demonstrated degenerative changes in the lumbar spine at one or both of the two lower levels (L4/L5 and/or L5/S1). All subjects gave their written informed consent to participate. The patients completed validated self-assessment questionnaires regarding anxiety and depression (HAD), catastrophizing (CSQ), kinesiophobia (TSK), and disability (ODI). Pain intensity ratings were performed separately for the back and the legs using the visual analogue scale (VAS). Pressure pain thresholds were assessed at eight different body sites with pressure algometry. The participants were assessed shortly before surgery and the questionnaires were mailed to the patients at one year follow up. The primary outcome variable was ODI at one year; the secondary outcome was change in ODI. Results Following surgery, there were statistically significant improvements regarding all the self-reported symptoms, including the outcome measure ODI. A higher value on ODI and higher ratings of leg pain preoperatively were found to predict a higher ODI score postoperatively. Conclusion We found reduced pain intensity ratings in the back and leg, reduced ratings of anxiety, depression, catastrophizing and kinesiophobia as well as reduced disability ratings following surgery compared to baseline. Furthermore, we found two predictors for postoperative disability, namely preoperative leg pain and disability, i.e., high leg pain and high disability ratings before surgery predicted high disability ratings following surgery. Our data stress the importance of pain analysis and diagnostics before surgery and indicate that pain drawings could be an initial tool to see if pain location is consistent with the radiological findings.