W B Katzman1, E Vittinghoff2, D M Kado3,4, N E Lane4, K E Ensrud5, K Shipp6. 1. Department of Physical Therapy and Rehabilitation Science, School of Medicine, University of California, 1500 Owens Suite 400, San Francisco, CA, 94158, USA. wendy.katzman@ucsf.edu. 2. Department of Epidemiology and Biostatistics, University of California, San Francisco, USA. 3. Departments of Family and Preventive Medicine and Internal Medicine, University of California, San Diego, USA. 4. Department of Internal Medicine, University of California, Davis, USA. 5. Minneapolis VA Health Care System, University of Minnesota, Minneapolis, USA. 6. Division of Physical Therapy, Department of Community and Family Medicine, Duke University, Durham, USA.
Abstract
SUMMARY: Biomechanical analyses support the theory that thoracic spine hyperkyphosis may increase risk of new vertebral fractures. While greater kyphosis was associated with an increased rate of incident vertebral fractures, our analysis does not show an independent association of kyphosis on incident fracture, after adjustment for prevalent vertebral fracture. Excessive kyphosis may still be a clinical marker for prevalent vertebral fracture. INTRODUCTION: Biomechanical analyses suggest hyperkyphosis may increase risk of incident vertebral fracture by increasing the load on vertebral bodies during daily activities. We propose to assess the association of kyphosis with incident radiographic vertebral fracture. METHODS: We used data from the Fracture Intervention Trial among 3038 women 55-81 years of age with low bone mineral density (BMD). Baseline kyphosis angle was measured using a Debrunner kyphometer. Vertebral fractures were assessed at baseline and follow-up from lateral radiographs of the thoracic and lumbar spine. We used Poisson models to estimate the independent association of kyphosis with incident fracture, controlling for age and femoral neck BMD. RESULTS:Mean baseline kyphosis was 48° (SD = 12) (range 7-83). At baseline, 962 (32%) participants had a prevalent fracture. There were 221 incident fractures over a median of 4 years. At baseline, prevalent fracture was associated with 3.7° greater average kyphosis (95% CI 2.8-4.6, p < 0.0005), adjusting for age and femoral neck BMD. Before adjusting for prevalent fracture, each 10° greater kyphosis was associated with 22% increase (95% CI 8-38%, p = 0.001) in annualized rate of new radiographic vertebral fracture, adjusting for age and femoral neck BMD. After additional adjustment for prevalent fracture, estimated increased annualized rate was attenuated and no longer significant, 8% per 10° kyphosis (95% CI -4 to 22%, p = 0.18). CONCLUSIONS: While greater kyphosis increased the rate of incident vertebral fractures, our analysis does not show an independent association of kyphosis on incident fracture, after adjustment for prevalent vertebral fracture. Excessive kyphosis may still be a clinical marker for prevalent vertebral fracture.
RCT Entities:
SUMMARY: Biomechanical analyses support the theory that thoracic spine hyperkyphosis may increase risk of new vertebral fractures. While greater kyphosis was associated with an increased rate of incident vertebral fractures, our analysis does not show an independent association of kyphosis on incident fracture, after adjustment for prevalent vertebral fracture. Excessive kyphosis may still be a clinical marker for prevalent vertebral fracture. INTRODUCTION: Biomechanical analyses suggest hyperkyphosis may increase risk of incident vertebral fracture by increasing the load on vertebral bodies during daily activities. We propose to assess the association of kyphosis with incident radiographic vertebral fracture. METHODS: We used data from the Fracture Intervention Trial among 3038 women 55-81 years of age with low bone mineral density (BMD). Baseline kyphosis angle was measured using a Debrunner kyphometer. Vertebral fractures were assessed at baseline and follow-up from lateral radiographs of the thoracic and lumbar spine. We used Poisson models to estimate the independent association of kyphosis with incident fracture, controlling for age and femoral neck BMD. RESULTS: Mean baseline kyphosis was 48° (SD = 12) (range 7-83). At baseline, 962 (32%) participants had a prevalent fracture. There were 221 incident fractures over a median of 4 years. At baseline, prevalent fracture was associated with 3.7° greater average kyphosis (95% CI 2.8-4.6, p < 0.0005), adjusting for age and femoral neck BMD. Before adjusting for prevalent fracture, each 10° greater kyphosis was associated with 22% increase (95% CI 8-38%, p = 0.001) in annualized rate of new radiographic vertebral fracture, adjusting for age and femoral neck BMD. After additional adjustment for prevalent fracture, estimated increased annualized rate was attenuated and no longer significant, 8% per 10° kyphosis (95% CI -4 to 22%, p = 0.18). CONCLUSIONS: While greater kyphosis increased the rate of incident vertebral fractures, our analysis does not show an independent association of kyphosis on incident fracture, after adjustment for prevalent vertebral fracture. Excessive kyphosis may still be a clinical marker for prevalent vertebral fracture.
Authors: Deborah M Kado; Dana Miller-Martinez; Li-Yung Lui; Peggy Cawthon; Wendy B Katzman; Teresa A Hillier; Howard A Fink; Kristine E Ensrud Journal: J Bone Miner Res Date: 2014-10 Impact factor: 6.741
Authors: Deborah M Kado; Mei-Hua Huang; Arun S Karlamangla; Peggy Cawthon; Wendy Katzman; Teresa A Hillier; Kristine Ensrud; Steven R Cummings Journal: J Bone Miner Res Date: 2013-01 Impact factor: 6.741
Authors: Alexander G Bruno; Katelyn Burkhart; Brett Allaire; Dennis E Anderson; Mary L Bouxsein Journal: J Bone Miner Res Date: 2017-03-28 Impact factor: 6.741
Authors: Mayke J van Dort; Johanna Hm Driessen; Elisabeth Apm Romme; Piet Geusens; Paul C Willems; Frank Wjm Smeenk; Emiel Fm Wouters; Joop Pw van den Bergh Journal: J Bone Miner Res Date: 2019-02-27 Impact factor: 6.741