[Comparative analysis of lumbar spine degeneration documented by x-rays versus large specimen cryomicrotome sections]

The extent of degenerative changes in the lumbar spine as seen on conventional radiographs is interpreted on the basis of visualized osseus structures and indirect signs such as diminution of disc height. In order to analyze the accuracy of these interpretations we compared and correlated different stages of degeneration in conventional radiographs with cuts of large-specimen cryomicrotome sections (LSCS), offering a direct macroscopic vision of the degenerative anatomic features.

A total of 50 human cadaver lumbar spines with 251 spine segments (Th 12 - S1) was investigated by plain radiograms and LSCS. The degenerative changes were differentiated into 5 stages for both diagnostic measures. Criteria for radiological degeneration were: diminution of disc space, presence of osteophytes and sclerosis of the endplates. Degenerative changes as seen by LSCS were evaluated by the following features: cracks in the endplate, bleeding into the intervertebral disc, alignment of the annulus fibrosus fibres and osseous alterations in the spine segment.

Complete matches of the evaluated radiological and macroscopic stages of degeneration were observed in 206 cases. A difference of 1 degree on the degeneration scale was registered in 42 segments, whereas a difference of 2 degrees was seen in 3 cases. The correlation coefficient between the degeneration stages of the two diagnostic measures scored rho = 0.883.

The comparison of the different degrees of degeneration in the lumbar spine as evaluated by both plain radiographs and LSCS revealed a good correlation.