In a prospective study 122 patients with herniated lumbar disc pre-operatively completed psychological questionnaires. Surgical outcome was evaluated 12 months post-operatively mainly by a composite clinical overall score (COS), and by its separate elements. Anxiety (HAD-A scale) and psychosomatic symptoms (MSPQ) had predictive value: fewer symptoms favoured a satisfactory overall outcome, and vice versa. The HAD-A Scale had a predictive power of poor (ppp) and satisfactory (pps) outcome of 28 and 81%, respectively. Correspondingly, for the MSPQ, the ppp and pps were 42 and 85%. Anamnestic and biological variables (including fibrinolytic variables: ECLT and PAI-1) predicted 20% of the outcome. By adding all psychological variables the prediction increased only to 24%, but the HAD-A Scale and the MSPQ were still significant. The results suggest that in order to further improve prediction of outcome, future studies should combine biological variables sensitive to the mental state of the patient, with psychometric assessments.