Mid and lower thoracic kyphosis changes during adulthood: the influence of age, sex and thoracic coronal curvature

Introduction There is conflicting data on how thoracic kyphosis changes throughout adulthood. We evaluated mid and lower thoracic kyphosis (MTK) in various age groups and the influence of age, sex and coronal curve (CC) on MTK. Material and methods We studied 1323 patients 15-80 years-old (54.4% females) previously evaluated with chest radiographs. We established three groups: patients 15-40 (group 1); 41-60 (group 2) and 61-80 years old (group 3). MTK (T5-T12) and CC were measured using Cobb's method. We established differences in MTK between groups using ANOVA with Bonferroni correction. We performed a correlation analysis of MTK with age and CC, and a linear regression analysis to determine if age, sex and CC independently predicted MTK. Results MTK increased with older age: mean MTK group 1 = 23.4 degrees; group 2 = 27.9 degrees and group 3 = 34.4 degrees, p < 0.01. The increase in MTK was observed in both genders. Scoliosis was more common in females (15.4%) than in males (6.7%), p < 0.01. MTK was correlated with age (r = 0.4; p < 0.01) and slightly correlated with CC (r = 0.07, p < 0.01). MTK was larger in females than in males (29.1 degrees vs. 27.6 degrees, p < 0.01). Age (ss-coefficient = 0.26) and CC (ss-coefficient = 0.14), but not sex, independently influenced MTK in the regression analysis. Conclusion MTK increases with advancing age during adulthood in both genders; CC, but not sex, was an independent predictor of MTK.

Automated summary

The study found that thoracic kyphosis increases with age in both genders during adulthood, while coronal curve serves as an independent predictor of MTK.