Exploring the relationship between static posture, dynamic balance, and subclinical pain in normal-weight healthy adults

Research Objectives: To assess the relationship between static postural alignment and dynamic balance in normal-weight, healthy adults with and without sub-clinical pain.

Design: Cross-sectional study

Setting: Human performance laboratory

Participants: 23 adults (4 male) age 19-47. Participants were excluded if they had a musculoskeletal abnormality, recent orthopedic injury, BMI >30, inner ear disorder, taking medication that may interact with pain pathways (including antidepressants), inability to stand barefoot for at least 30 minutes, or inability to give written consent in English.

Interventions: N/A

Main Outcome Measures: Sagittal plane postural alignment was assessed using a vertical plumb line anchored at lateral malleolus. Deviation from plumb was measured for the greater trochanter, lateral acromion, and tragus of the ear. Frontal plane postural alignment was assessed using a vertical plumb anchored at midpoint between the feet. Degrees of deviation from plumb was measured for the glabella, lateral acromion, and ASIS. Functional balance was measured by the Y-balance composite score normalized to leg length. Participants were considered to have sub-clinical pain if they identified at least one painful body area for which they have not sought care in the past 12 months and do not plan to seek care in the next six months.

Results: There were no significant correlations between any measures of postural alignment and performance on the Y-balance test of dynamic balance. There was no correlation between the presence of sub-clinical pain and performance on the Y-balance test or postural alignment.

Conclusions: Among healthy, normal-weight adults performing functional balance tasks, the biomechanical consequences of postural misalignment can be compensated by other body systems. In this sample, neither postural alignment nor functional balance capabilities were correlated with subclinical musculoskeletal pain. These results indicate that influences from the nervous system, vestibular function, and cognition may play an important role in dynamic balance and the experience of subclinical pain. Results support de-emphasizing postural correction in clinical management of musculoskeletal pain and further exploring non-biomechanical factors affecting the experience of musculoskeletal pain.

Author(s) Disclosures: The author reports no conflicts of interest.