Reliability of sagittal vertical axis measurement and association with measures of age-related hyperkyphosis

Abstract

[Purpose] Persons with age-related hyperkyphosis often have concomitant sagittal plane imbalance of the spine. This study investigated the reliability of sagittal vertical axis (SVA) measurement of sagittal balance, association between thoracic Cobb angle of kyphosis and SVA measure of sagittal balance, and compared the degree of SVA in males and females with age-related hyperkyphosis. [Participants and Methods] Measurements of SVA and Cobb angle of kyphosis were obtained from baseline radiographs of 112 community-dwelling males and females, mean age 70.0 (SD=5.7) years with kyphosis ≥40 degrees, recruited for a randomized controlled trial. Spearman correlation coefficients were used to determine associations between SVA and kyphosis, and Wilcoxon nonparametric tests to compare SVA between genders. [Results] SVA was acquired with excellent intra-rater [0.95 (95% CI: 0.88, 0.98)] and inter-rater reliability [0.93 (95% CI: 0.83,0.97)]. There was no significant correlation between Cobb angle of thoracic kyphosis and SVA, (r=−0.05). More males than females had sagittal imbalance (SVA≥5 cm). [Conclusion] In older adults with hyperkyphosis, SVA was a reliable measure of sagittal balance, and more extreme in males. SVA was not associated with Cobb angle of thoracic kyphosis, and could be considered an independent phenotype of age-related hyperkyphosis to be targeted in future intervention trials.

Artificial Intelligence for Automatic Measurement of Sagittal Vertical Axis Using ResUNet Framework

“…Kyrölä et al [27] reported the ICC score of 0.99 (95% CI: 0.98, 1.00) for SVA in unselected adults with degenerative spine disorders. In a previous study, Katzman et al [28] also showed a high ICC score of 0.93 (95% CI: 0.83, 0.97) in older adults with hyperkyphosis.…”

The association between hyperkyphosis and fall incidence among community-dwelling older adults

“…Yet, rather uniformly, sagittal inclination of the spine as a whole and the lumbar lordosis angle have been shown to be associated to impaired balance [ 13 , 41 ] and a higher fall risk [ 18 , 19 , 41 – 43 ]. The Cobb angle is not always correlated to inclination of the total spine, as shown by Demarteau et al and Katzman et al in community-dwelling older adults [ 12 , 13 ].…”

“…Balance may be influenced by thoracic hyperkyphosis, an excessive curvature of the thoracic spine. Hyperkyphosis may shift the center of mass of the body forward if compensation in the lumbar spine and hip region is not sufficient and thereby cause gait disorders and disruption of balance [11][12][13]. Hyperkyphosis is frequently found in older adults [14].…”

The Association Between Physical Function and Hyperkyphosis in Older Females: A Systematic Review and Meta-analysis

“…14,44 Interestingly, 3 of these studies used occiput to wall measurements as their indicators of hyperkyphosis. 14,31,44 It is possible that the forward-head component of hyperkyphosis that is captured with the occiput to wall measurement, and is present in some but not all individuals with hyperkyphosis, 59 has a greater negative impact on gait speed than thoracic curvature alone. The forward-head phenotype of hyperkyphosis alters the center of mass, affects balance, and could explain why gait speed might be impaired.…”