The screening and intervention of thoracic hyperkyphosis among Chinese community-dwelling older adults

Abstract

Thoracic hyperkyphosis affects 20%–55% of community-dwelling older adults globally, with adverse effects on both physical and psychological health. Early screening and intervention are essential as hyperkyphosis is remediable with noninvasive interventions, e.g. exercise, manual therapy, and orthosis. Previous studies were mainly conducted overseas. Findings on the prevalence, adverse effects, and intervention effects may not be generalized to Chinese older adults due to differences in ethnicity, hyperkyphosis status, and exercise habit. Furthermore, radiation-free angle measurements – with a manual inclinometer or Flexicurve ruler – are widely used in communities. Manual inclinometers directly measure the kyphosis angle, providing an alternative gold standard, while Flexicurves need a translating formula to obtain angular results. However, the formula has not been tested among older adults without hyperkyphosis or Chinese older adults. This thesis aimed to 1) investigate the prevalence and adverse effects of thoracic hyperkyphosis for Chinese community-dwelling older adults; 2) examine the agreement between manual inclinometer and Flexicurve measured kyphosis angles among Chinese older adults with different hyperkyphosis statuses; 3) systematically review the effects of noninvasive interventions on hyperkyphosis; and 4) explore the feasibility and effects of home-based kyphosis-specific exercises on the kyphosis angle and physical performance of Chinese older adults with hyperkyphosis. A cross-sectional study recruited 395 older adults in Wuhan, China. Hyperkyphosis prevalence was estimated according to the inclinometer angle. Logistic regression examined the association between hyperkyphosis and physical performance. I used the same database to analyze the agreement level between the manual inclinometer and Flexicurve measurements. A meta-analysis was performed to estimate the pooled effect size of noninvasive interventions on hyperkyphosis. Finally, I designed a home-based exercise intervention and conducted a one-group pre-post design feasibility study. Intervention effects on the kyphosis angle and physical performance were explored. Based on these findings, I developed a randomized controlled trial (RCT) protocol. Three quarters (75.2%) of the Chinese community-dwelling older adults in this study had hyperkyphosis. Compared with those having alignment posture, older adults with hyperkyphosis had three to six times the risk of impaired performance in all physical performance tests. Poor agreement between tools for kyphosis angle measurement was observed regardless of hyperkyphosis status, with the Flexicurve angle being significantly smaller than the inclinometer angle. Meta-analysis recruiting 12 RCTs found noninvasive interventions had a -0.83 pooled effect size. The exercise-only interventions had a moderate pooled effect size (-0.54) and were the most frequently investigated interventions. The feasibility study recruiting 20 older adults with hyperkyphosis had satisfactory adherence. After the six-week intervention, kyphosis angle decreased by 11.0º ± 6.8º (p <0.001) and 9.8º ± 6.3º (p <0.001) in relaxed and best standing postures, respectively. Participants also had significant improvement in pain, self-image, and physical performance. However, participants prefer using fragmented time rather than a continuous hour for home practice. In the RCT protocol, the one-hour practice has been divided into three shorter sessions. Most of the Chinese community-dwelling older adults in this study were adversely affected by thoracic hyperkyphosis. Flexicurve measurements needed the Chinese-fit formula. Home-based kyphosis-specific exercises showed potential as a feasible and effective intervention. An RCT will be conducted.