The Association Between Physical Function and Hyperkyphosis in Older Females: A Systematic Review and Meta-analysis.

Background and purpose: Thoracic hyperkyphosis may adversely influence physical function in older adults, but the literature is mixed and confounded by possible sex differences. This systematic review and meta-analysis aimed to examine the association between hyperkyphosis and physical function in older females.

Methods: Scopus, ISI Web of Science, Cochrane Library, PubMed, CINAHL, and PEDro databases were searched through 2021 for studies that included measures of thoracic hyperkyphosis and physical function with extractable data for women older than 60 years. Studies were excluded if they were qualitative, case reports, case series, ecological studies, reviews, or were not published in English. The study quality and risk of bias were assessed using checklists from the National Heart, Lung, and Blood Institute. Data were synthesized using Cohen's d effect size and 95% confidence interval (CI), and random-effects models were used for the meta-analyses.

Results and discussion: Three cohort and 22 cross-sectional studies of fair to good quality met the inclusion criteria. Eight studies reporting single-group data showed a moderate association between greater kyphosis angles and lower physical function ( d = -0.57; 95% CI -0.73, -0.40). Fourteen studies reporting 2-group data showed a large negative effect on physical function for groups with greater kyphosis angles ( d = -1.16; 95% CI -1.53, -0.78). Three studies that reported multivariate data also tended to show negative associations between physical function and hyperkyphosis. Limitations include a relative lack of causal evidence; confirming causation requires additional longitudinal studies. Studies have assessed various physical function categories, including strength, gait, and balance. Future studies could determine the categories of function most affected so that preventive interventions could target hyperkyphosis appropriately.

Conclusions: Hyperkyphosis was associated with lower physical function in older women. Three cohort studies suggest that greater kyphosis angles may predict greater loss of physical function over time. These results imply that therapies that help to minimize hyperkyphosis may help preserve function in older women.