Abstract
Summary
There are many ways to measure thoracic kyphosis ranging from simple clinical to more complex assessments. We evaluated the correlation among four commonly used kyphosis measures: Cobb angle, Debrunner kyphometer, kyphotic index, and the blocks method. Each measure was correlated with the others, confirming high clinical and research applicability.
Introduction
The purpose of this study was to assess the associations among four commonly used measures of thoracic kyphosis in older adults.
Methods
Seventy two men and women aged 65–96 were recruited from the San Diego community. Four kyphosis measures were assessed in the same person during a baseline clinic visit. Two measures were done in the lying (L) and two in the standing (ST) position: (1) Cobb angle calculated from dual X-Ray absorptiometry (DXA) images (L), (2) Debrunner kyphometer (DK) angle measured by a protractor (ST), (3) kyphotic index (KI) calculated using an architect’s flexicurve ruler (ST), and (4) the blocks method involving counting the number of 1.7 cm-thick blocks required to achieve a neutral head position while lying flat on the DXA table (L). Spearman rank correlation coefficients were used to determine the strength of the association between each kyphosis measure.
Results
Using the Cobb angle as the gold standard, the blocks method demonstrated the lowest correlation (r s = 0.63, p < 0.0001), the Debrunner method had a moderate correlation (r s = 0.65, p < 0.0001), and the kyphotic index had the highest correlation (r s = 0.68, p < 0.0001). The correlation was strongest between the kyphotic index and the Debrunner kyphometer (r s = 0.76, p < 0.0001).
Conclusion
In older men and women, all four measures of thoracic kyphosis were significantly correlated with each other, whether assessed in the lying or standing position. Thus, any of these measures demonstrate both potential clinical and research utility.
References
Ensrud KE, Black DM, Harris F et al (1997) Correlates of kyphosis in older women. The Fracture Intervention Trial Research Group. J Am Geriatr Soc 45(6):682–687
Schneider DL, von Mühlen D, Barrett-Connor E et al (2004) Kyphosis does not equal vertebral fractures: the Rancho Bernardo study. J Rheumatol 31(4):747–752
Kado DM, Huang MH, Karlamangla AS et al (2013) Factors associated with kyphosis progression in older women: 15 years’ experience in the study of osteoporotic fractures. J Bone Miner Res 28(1):179–187. doi:10.1002/jbmr.1728
Sinaki M, Itoi E, Roger JW et al (1996) Correlation of back extensor strength with thoracic kyphosis and lumbar lordosis in estrogen-deficient women. Am J Phys Med Rehabil 75(5):370–374
Kado DM, Huang MH, Barrett-Connor E et al (2005) Hyperkyphotic posture and poor physical functional ability in older community-dwelling men and women: the Rancho Bernardo study. J Gerontol A Biol Sci Med Sci 60(5):633–637
Kado DM, Huang MH, Nguyen CB et al (2007) Hyperkyphotic posture and risk of injurious falls in older persons: the Rancho Bernardo Study. J Gerontol A Biol Sci Med Sci 62(6):652–657
Kado DM, Miller-Martinez D, Lui LY (2014) Hyperkyphosis, kyphosis progression, and risk of non-spine fractures in older community dwelling women: the study of osteoporotic fractures (SOF). J Bone Miner Res 29(10):2210–2216. doi:10.1002/jbmr.2251
Kado DM, Lui LY, Ensrud KE et al (2009) Hyperkyphosis predicts mortality independent of vertebral osteoporosis in older women. Ann Intern Med 150(10):681–687
Carman DL, Browne RH, Birch JG (2009) Measurement of scoliosis and kyphosis radiographs. Intraobserver and interobserver variation. J Bone Joint Surg Am 72(3):328–333
Öhlén G, Spangfort E, Tingvall C (1989) Measurement of spinal sagittal configuration and mobility with Debrunner’s kyphometer. Spine 14:580–583
Milne JS, Lauder IJ (1976) The relationship of kyphosis to the shape of vertebral bodies. Ann Hum Biol 3(2):173–179
Lundon KM, Li AM, Bibershtein S (1998) Interrater and intrarater reliability in the measurement of kyphosis in postmenopausal women with osteoporosis. Spine 23(18):1978–1985
Azadinia F, Kamyab M, Behtash H et al (2014) The validity and reliability of noninvasive methods for measuring kyphosis. J Spinal Disord Tech 27(6):E212–E218. doi:10.1097/BSD.0b013e31829a3574
Kado DM, Christianson L, Palermo L et al (2006) Comparing a supine radiologic versus standing clinical measurement of kyphosis in older women: the fracture intervention trial. Spine 31(4):463–467
Greendale GA, Nili NS, Huang MH et al (2011) The reliability and validity of three non-radiological measures of thoracic kyphosis and their relations to the standing radiological Cobb angle. Osteoporos Int 22(6):1897–1905. doi:10.1007/s00198-010-1422-z
Ettinger B, Black DM, Palermo L et al (1994) Kyphosis in older women and its relation to back pain, disability, and osteopenia: the study of osteoporotic fractures. Osteoporos Int 4(1):55–60
Katzman WB, Harrison SL, Fink HA et al (2015) Physical function in older men with hyperkyphosis. J Gerontol A Biol Sci Med Sci 70(5):635–640. doi:10.1093/gerona/glu213
Katzman WB, Vittinghoff E, Ensrud K et al (2011) Increasing kyphosis predicts worsening mobility in older community-dwelling women: a prospective cohort study. J Am Geriatr Soc 59(1):96–100. doi:10.1111/j.1532-5415.2010.03214.x
Katzman WB, Miller-Martinez D, Marshall LM et al (2014) Kyphosis and paraspinal muscle composition in older men: a cross-sectional study for the Osteoporotic Fractures in Men (MrOS) research group. BMC Musculoskelet Disord 15:19. doi:10.1186/1471-2474-15-19
Yamamoto J, Bergstrom J, Davis A, Wing D, Nichols J, Kado D (2015) Trunk lean mass and its association with 3 measures of kyphosis in older dwelling persons. J Am Geriatr Soc 63(Suppl 1):S14
Acknowledgments
This work was supported by the University of California, San Diego’s Department of Family Medicine and Public Health, the University of California Academic Senate the UCSD Stein Institute for Research on Aging, and NIH/NIAMS AR06828.
Author information
Authors and Affiliations
Corresponding author
Ethics declarations
Conflict of interest
None.
Rights and permissions
About this article
Cite this article
Tran, T.H., Wing, D., Davis, A. et al. Correlations among four measures of thoracic kyphosis in older adults. Osteoporos Int 27, 1255–1259 (2016). https://doi.org/10.1007/s00198-015-3368-7
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00198-015-3368-7