Spencer L1, McKenna L1, Fary R1, Ho R1, Briffa K1
1Curtin University, School of Physiotherapy and Exercise Science, Perth, Australia
Background: The physical characteristics of postmenopausal women that are associated with upper back pain (UBP) are not well-understood. Common postural features of postmenopausal women include an accentuated thoracic kyphosis; more forward head and rounded shoulders. Related to these features are characteristics that become more likely with increasing age and include: weak back muscles; stiff intervertebral joints and low bone density. Physical characteristics that become more likely following menopause that could also be important are changes in lean muscle mass; breast size and ptosis and thoracic vertebral fractures. The association between these physical characteristics and UBP have not been collectively examined in postmenopausal women.
Purpose: The aim of this study was to identify the physical characteristics that are associated with UBP and UBP severity in postmenopausal women.
Methods: This was a cross-sectional study of postmenopausal women. Self-reported UBP status (presence within the previous month) and severity (Numerical Rating Scale) were collected. Physical characteristics measured were: height; weight; breast size (bra size); breast ptosis; upper back extensor endurance (Isometric chest raise test); posture (head, shoulder and upper back) (photogrammetry); thoracic extension mobility (photogrammetry); bone mineral density (Dual x-ray absorbtometry, DXA); body composition (DXA); thoracic kyphosis (radiography); thoracic osteoarthritis and thoracic vertebral fracture (radiography). Univariate logistic regression analysis assessed between-group differences. Each physical characteristic was entered as a predictor variable of UBP (yes/no) with adjustment for age and breast size. Variables considered significant after adjustment for age and breast size were entered into a multivariate model. Linear regression analysis was used to examine the univariate association of each physical characteristic with UBP severity in the UBP group.
Results: 119 postmenopausal women participated in the study. The physical characteristics in the final model and predicting UBP were: age (OR: 0.81, 95%CI:0.75-0.89); breast size (OR:1.23, 95% CI: 1.01-1.51); height (OR:0.88, 95% CI:0.81-0.95) and upper back extensor endurance (OR: 0.99, 95%CI:0.98-1.00). The final multivariate model was significant (p .001) and explained 38% of the variance in UBP. Women who were older, taller, had smaller breasts and had better upper back extensor endurance were associated with lower odds for UBP. UBP severity was significantly correlated with lean muscle mass (r=-0.40, p=.002) and thoracic extension mobility (r= -0.35, p=.006). Collectively these physical characteristics explained 27% of the variance in UBP severity (p .05).
Conclusion(s): Upper back extensor endurance is an important, modifiable physical characteristic, independent of age and breast size that is associated with UBP in postmenopausal women. In women suffering with UBP, thoracic extension mobility and lean muscle mass are physical characteristics that are significantly associated with UBP severity. Future research should seek to determine which interventions incorporating these factors are effective for UBP in postmenopausal women. Contrary to popular accounts, postural physical characteristics appear unrelated to UBP and UBP severity in postmenopausal women.
Implications: Postmenopausal women, irrespective of their age may be less likely to suffer from UBP and higher levels of pain if they maintain good upper back extensor muscle endurance and back extension mobility.
Keywords: Upper back pain, Back muscle endurance, Postmenopausal women
Funding acknowledgements: Primary researcher supported by funding from an Australian Government Research Training Program Scholarship and Curtin University Research Scholarship.
Purpose: The aim of this study was to identify the physical characteristics that are associated with UBP and UBP severity in postmenopausal women.
Methods: This was a cross-sectional study of postmenopausal women. Self-reported UBP status (presence within the previous month) and severity (Numerical Rating Scale) were collected. Physical characteristics measured were: height; weight; breast size (bra size); breast ptosis; upper back extensor endurance (Isometric chest raise test); posture (head, shoulder and upper back) (photogrammetry); thoracic extension mobility (photogrammetry); bone mineral density (Dual x-ray absorbtometry, DXA); body composition (DXA); thoracic kyphosis (radiography); thoracic osteoarthritis and thoracic vertebral fracture (radiography). Univariate logistic regression analysis assessed between-group differences. Each physical characteristic was entered as a predictor variable of UBP (yes/no) with adjustment for age and breast size. Variables considered significant after adjustment for age and breast size were entered into a multivariate model. Linear regression analysis was used to examine the univariate association of each physical characteristic with UBP severity in the UBP group.
Results: 119 postmenopausal women participated in the study. The physical characteristics in the final model and predicting UBP were: age (OR: 0.81, 95%CI:0.75-0.89); breast size (OR:1.23, 95% CI: 1.01-1.51); height (OR:0.88, 95% CI:0.81-0.95) and upper back extensor endurance (OR: 0.99, 95%CI:0.98-1.00). The final multivariate model was significant (p .001) and explained 38% of the variance in UBP. Women who were older, taller, had smaller breasts and had better upper back extensor endurance were associated with lower odds for UBP. UBP severity was significantly correlated with lean muscle mass (r=-0.40, p=.002) and thoracic extension mobility (r= -0.35, p=.006). Collectively these physical characteristics explained 27% of the variance in UBP severity (p .05).
Conclusion(s): Upper back extensor endurance is an important, modifiable physical characteristic, independent of age and breast size that is associated with UBP in postmenopausal women. In women suffering with UBP, thoracic extension mobility and lean muscle mass are physical characteristics that are significantly associated with UBP severity. Future research should seek to determine which interventions incorporating these factors are effective for UBP in postmenopausal women. Contrary to popular accounts, postural physical characteristics appear unrelated to UBP and UBP severity in postmenopausal women.
Implications: Postmenopausal women, irrespective of their age may be less likely to suffer from UBP and higher levels of pain if they maintain good upper back extensor muscle endurance and back extension mobility.
Keywords: Upper back pain, Back muscle endurance, Postmenopausal women
Funding acknowledgements: Primary researcher supported by funding from an Australian Government Research Training Program Scholarship and Curtin University Research Scholarship.
Topic: Musculoskeletal: spine; Pain & pain management; Musculoskeletal
Ethics approval required: Yes
Institution: Curtin University
Ethics committee: Human Research Ethics Committee
Ethics number: RDHS-267-15
All authors, affiliations and abstracts have been published as submitted.
