On the controversies of spine surgery research

Abstract

This thesis is about effectiveness of surgical interventions in the spine and the value of different methodologies for providing a valid answer.

In the first part five systematic reviews were performed. One reviewed cervical degenerative disc disease comparing the different anterior fusion techniques. Two were performed on lumbar disc herniation comparing conservative interventions with surgical and comparing the several surgical techniques. One was on lumbar degenerative disc disease and evaluated disc replacement. The fifth evaluated interventions for low grade lumbar isthmic spondylolisthesis.

In the second part systematic reviews were searched, selected and appraised in two meta-epidemiological studies. Spinal research suffers from specific problems with regard to randomization and related to that, blinding and allocation concealment. These are factors that have in other medical fields been shown to introduce biased results. Our studies showed that observational studies in spinal surgery research do not result in an overestimation of the treatment effect in contrast to other medical disciplines.

Finally, the experience gained from these studies has resulted in several opinion papers that aim to guide the scientific field in using the most appropriate methods in spine surgery research.