Purpose: A prospective study to evaluate whether certain baseline characteristics can predict outcome in patients treated with disc prosthesis or multidisciplinary rehabilitation.
Methods: Secondary analysis of 154 patients with chronic low back pain (LBP) for at least 1 year and degenerative discs originally recruited for a randomized trial. Outcome measures were Oswestry Disability Index (ODI) dichotomized to < or ≥15 points improvement and whether subjects were working at 2-year follow-up. A multiple logistic regression analysis was used.
Results: In patients treated with disc prosthesis, long duration of LBP and high Fear-Avoidance Beliefs for work (FABQ-W) predicted worse ODI outcome [odds ratio (OR) = 1.9, 95% confidence interval (CI) 1.2-3.2 and OR = 1.7, CI 1.2-2.4 for every 5 years or 5 points]. Modic type I or II predicted better ODI outcome (OR = 5.3, CI 1.1-25.3). In patients treated with rehabilitation, a high ODI, low emotional distress (HSCL-25), and no daily narcotics predicted better outcome for ODI (OR = 2.5, CI 1.4-4.5 for every 5 ODI points, OR = 2.1, CI 1.1-5.1 for every 0.5 HSCL points and OR = 23.6, CI 2.1-266.8 for no daily narcotics). Low FABQ-W and working at baseline predicted working at 2-year follow-up after both treatments (OR = 1.3, CI 1.0-1.5 for every 5 points and OR = 4.1, CI 1.2-13.2, respectively).
Conclusions: Shorter duration of LBP, Modic type I or II changes and low FABQ-W were the best predictors of success after treatment with disc prosthesis, while high ODI, low distress and not using narcotics daily predicted better outcome of rehabilitation. Low FABQ-W and working predicted working at follow-up.