Degenerative lumbar listhesis and bone mineral density in elderly women. The Study of osteoporotic fractures

Study Design. A cross-sectional and prospective study. Objectives. To investigate the association between lumbar listhesis in elderly white women and bone mineral density at the spine, hip, radius, and calcaneus. Summary of Background Data. Several types of degenerative spinal changes nave been found to be associated with high bone mineral density at the spine and other body sites. Methods. Lateral radiographs of the lumbar spine for 1400 elderly women enrolled in the Study of Osteoporotic Fractures were digitized. Listhesis (antero and retro) was assessed at L3-L4, L4-L5, and L5-S1. Bone mineral density was measured at the spine, hip, calcaneus, and the distal and proximal radius. Results. After adjusting the data for age and body mass index, retrolisthesis at L3-L4, L4-L5, and L5-S1 was associated with mean spinal bone mineral density levels that were 9% to 13% higher compared with those levels in women with no listhesis (P < 0.0001). In addition, bone mineral density at the hip and appendicular sites increased from 4% to 9%. The mean lumbar spinal bone mineral density of women with anterolisthesis at L3-L4 was 12% higher (P < 0.05) than that of women with no listhesis; it was the same for both groups at L4-L5 and was 7% lower (P < 0.005) at L5-S1. At L5-S1 the bone mineral density level at the hip and appendicular sites was also lower among the women with anterolisthesis at that level. Conclusions. This study suggests that retrolisthesis, like other spinal degenerative diseases, is assoclated with increased spinal bone mineral density. Anterolisthesis, however, may involve a different etiology, because its association with bone mineral density varies by spinal level.