Lumbosacral transitional vertebrae: prevalence, associated degenerative changes, and association with low back pain in Finnish population.

Lumbosacral transitional vertebra (LSTV) is a common anatomical variant of the lumbar spine. There are several types of LSTVs and they are commonly classified using the Castellvi classification. The presence of LSTV causes biomechanical changes which predispose the lumbar spine to degenerative changes. Degenerative changes in the lumbar spine are more common in patients who experience low back pain than in patients without low back pain. LSTV has had a contested association with low back pain, but recent studies show a positive association. Degenerative changes in the lumbar spine can be the cause of pain in LSTVs.

The aims of this thesis were to assess the prevalence of LSTV in Finnish population, evaluate the association between degenerative changes and LSTV, and investigate the association between low back pain and LSTV. Study populations were gathered from patients who were imaged at Oulu University Hospital. We also evaluated lumbar spine MRI examinations from the Northern Finland Birth Cohort 1966.

The prevalence of LSTV was 29% and 21% in two Finnish study populations. Castellvi type II-IV LSTVs were associated with greater lumbar degeneration and Castellvi type III LSTV was associated with low back pain. The results of this thesis can aid in the diagnosis and treatment of LSTV patients who experience low back pain.