The objective of this study was to assess disability, Health-Related Quality of Life (HRQoL) and health utility in patients undergoing spinal fusion surgery. Since 2008 all patients undergoing non-urgent spinal fusion in Tampere University Hospital and Jyväskylä Central Hospital have been invited to the spinal database. Patients´ data were collected prospectively, prior to surgery and at three months, one year and two years postoperatively and there are different follow-up periods in sub-studies. A general population sample was also drawn and matched for age, gender and residential area for purposes of comparison with the fusion patients. Three months post surgery the 173 patients showed a significant improvement in disability when assessed with the translated, validated and psychometrically tested Finnish version 2.0 of the Oswestry Disability Index (ODI). The mean preoperative total ODI score was 45 (SD 17) and the mean decrease at three months was -19 (95% CI: -22 to -17). At the one-year disability analysis only minor addition in improvement was observed as compared to the ODI at three months. In the general population the ODI was 15 (SD 17) in females and 9 (SD 13) in males. Despite the improvement in disability among the patients, both sexes still had higher mean ODI values at one year than the general population (p<0.001).
The changes in HRQoL were assessed with the 36-item Short Form Health Survey (SF-36). The SF-36 was also used divided in two component scores: the Physical Component Summary Score (PCS) and the Mental Component Summary Score (MCS). At three months the positive changes were significant in both the PCS and the MCS. In addition the relationship between disability and HRQoL was significant. Although at one year both the female and male patients attained the general population level in the MCS, in the PCS the patients fell behind the general population. In the health utility analysis, the data of 242 fusion patients were analysed stratified into five surgical indication groups (degenerative olisthesis, isthmic olisthesis, spinal stenosis, degenerative disc disease or disc herniation and postoperative conditions). At two years the improvements in the SF-6D scores were significant in all groups (p<0.001). Furthermore, the changes in the SF-6D scores did not differ significantly between the groups (p=0.40 In conclusion the evaluation of the present prospectively collected unselected patient material confirms that although the patients do not reach the level of the general population the patients get significant benefit from the fusion procedure in the current practise. This benefit is apparent already in the early phase of recovery and the positive changes stay stable during the two-year follow-up.