Scoliosis in Adults Aged Forty Years and Older

STUDY DESIGN: Retrospective study. OBJECTIVE: To identify the prevalence of lumbar scoliosis in adults ≥ 40 years old; to investigate relationships between scoliosis prevalence and 3 parameters (age, race, gender); and to determine any effect of those parameters on curve severity. SUMMARY OF BACKGROUND DATA: As the population ages, the incidence of degenerative spine conditions increases. More patients are being diagnosed with and treated for spinal deformities, including scoliosis. METHODS: We examined dual-energy x-ray absorptiometry lumbar spine images of 3185 individuals ≥ 40 years old (average, 60.8 years; range, 40-97 years), obtained July 2002 to June 2005, to determine the presence of scoliosis (i.e., a curvature of ≥ 11.0°) by digitally measuring Cobb angles. Patients with a history of previous lumbar spinal surgery were excluded, leaving 2973 individuals for final evaluation. We used SAS system software, version 9.1 (SAS Institute, Inc., Cary, NC) to investigate the relationship between the prevalence of scoliosis and the variables of age, race, and gender, we then examined for any effect that these variables had on curve severity. RESULTS: We identified scoliosis (i.e., a Cobb angle of ≥ 11°) in 263 of 2973 patients. Age was associated with an increased prevalence of scoliosis, e.g., 40 to 50 years old, 3.14%; ≥ 90 years old, 50%. Prevalence rates differed among races (e.g., 11.1% for whites and 6.5% for African Americans) but were similar for men and women. Most patients had mild curves (80.6%), there was no difference in the distribution of curve severity by gender or age, and African Americans were more likely to have mild curves (94.3%) than were other races. CONCLUSION: The prevalence of scoliosis in our patients ≥ 40 years old was 8.85% and was associated with age and race, but not with gender. Most curves in our population were mild; curve severity was associated with race but not with age or gender.