Relationship between abnormal sagittal global alignment and severity of vertebral fracture in patients with osteoporosis
Refereed conference paper presented and published in conference proceedings

Other information
Osteoporosis is a major health condition characterized by low bone mass and diminished bone strength, leading to skeletal fragility and increase risk of hip, wrist and spinal fracture [1]. Osteoporotic vertebral compression fractures (VCF) of the spine is very common and at times underdiagnosed [2] and was found to be associated with the increased mortality, morbidity, and overall decline in quality of life in the elderly [3]. Studies have shown that osteoporotic patients with vertebral fracture had significantly higher thoracic kyphosis and lower lumbar lordosis in the spinal sagittal alignment profile [4]. However, the influence of vertebral fractures on whole-body compensatory mechanism, including pelvic retroversion and knee flexion, remains unclear. The aim of this study was to compare the global body sagittal alignment and quality of life in elderly osteoporotic subjects with and without vertebral compression fractures, and to investigate the relationship between the changes of these sagittal alignment with the severity of the fracture.
Materials and methods
A consecutive series of 72 osteoporotic subjects with BMD documentation were prospectively enrolled. Clinical assessment, including age, body height and weight, were recorded. Global sagittal alignment was taken with EOS® low dose X-ray imaging system. The number and location of VCF were assessed, and the severity of VCF was evaluated by Spinal Deformity Index [5]. Measurement on global sagittal alignment was done by using T1 pelvic angle (TPA) and global sagittal angle (GSA) (Fig. 1). Quality of life assessment was completed for each subject by validated questionnaires: Oswestry Disability Index (ODI) and Short-form (SF)-12.
The TPA and GSA were significantly correlated with SF-12 and ODI in osteoporotic patients. The patients with VCF were found to have significantly higher TPA and SVA. The number and severity of VCF significantly correlated with global sagittal alignment. Discriminative value for identification of patients with at least one VCF, assessed by Area Under the Curves (AUCs) was 0.661 and 0.766 for TPA and GSA, respectively. Using multivariate analysis, parameters significantly associated with abnormal global alignment (GSA) were the number (OR=2.96, P=0.01) and severity of VCF (OR=4.23, P<0.0001) and age (OR=1.07, P=0.02) (Table 1).
Similar to previous studies on adult spinal deformity, the parameters of TPA and GSA were significantly correlated with quality of life measurement in osteoporotic patients. In addition, there was differences in TPA and GSA found between osteoporotic patients with and without VCF. This is the first study to report deteriorated global alignment in osteoporotic patients with VCF. There was a negative effect of the number and severity of VCF on global alignment. Further longitudinal study based on these early findings with a larger cohort would be important in the future to define more quantitatively the relationship that might inform better the clinical prognostication, prevention and treatment strategy.
The osteoporotic patients with VCF had a worse overall global sagittal alignment. The number and severity of VCF are strong determinants of global sagittal balance. The osteoporotic patients with a poorer sagittal global alignment may imply more severe vertebral fracture. Based on our current result, the changes in global sagittal alignment may be a potential prognostic indicator for vertebral facture in osteoporotic patients.
All Author(s) ListZongshan Hu, Gene C.W. Man, Sheung Wai Law, Anthony Kwok, Jack C.Y. Cheng
Name of ConferenceThe 12th Meeting of International Research Society on Spinal Deformities (IRSSD)
Start Date of Conference14/06/2018
End Date of Conference16/06/2018
Place of ConferenceUtrecht
Country/Region of ConferenceNetherlands
Proceedings TitleScoliosis and Spinal Disorders
Volume Number13
Issue NumberSupp 1
Pages24 - 25
LanguagesEnglish-United Kingdom

Last updated on 2018-16-11 at 15:49