[Depressivity and successful outcome of spinal surgery].

Introduction: The relationship between depression and the outcome of low back surgery was investigated. Data analysis was based on two assumptions: (1) Presurgical assessments of depression are correlated with the outcome of surgery, and, therefore, depression can be interpreted as a risk factor for surgical failure. (2) Postsurgical assessments of depression are correlated with the outcome of surgery, and therefore, depression can be interpreted as a response to treatment failure.

Methods: The sample was made up of 78 patients who had undergone lumbar nucleotomy and 132 patients with lumbar spondylodesis. Treatment outcome was evaluated 6 months after surgery in the nucleotomy group and 9 months after surgery in the spondylodesis group. Depression was assessed with the Beck Depression Inventory (BDI). Measures of treatment outcome were an objective rating system for the surgical result, functional impairment, return to work, subjective estimations of the patient, and pain intensity.

Results: Presurgical depression scores showed no significant relationship with surgical outcome in nucleotomy patients. In spondylodesis patients, however, there was a significant negative correlation with the patients' subjective outcome ratings. Postsurgical depression scores, on the other hand, were significantly related to almost all of the outcome variables in both treatment groups. Patients with clinically relevant postsurgical depression scores were significantly more likely not to benefit sufficiently from surgery than those with clinically not relevant depression scores.

Discussion: Our findings favour assumption 2 over assumption. 1. In the light of our findings, depressiveness is interpreted as a response to a non-beneficial outcome of surgery. The need for an interdisciplinary approach combining psychological counseling or treatment and physical therapy for those patients who do not benefit from surgery is discussed.