Postural deviations in individuals with chronic obstructive pulmonary disease (COPD)

RATIONALE: While upper back pain in chronic obstructive pulmonary disease (COPD) suggests that postural dysfunction is a potential cause, the extent of postural deviation in COPD is unknown. OBJECTIVE: This study compared postural measurements in people with COPD to healthy controls and explored the relationship between posture deviations and pain in COPD. METHODS: Participants with COPD and age, gender, BMI and comorbidity-matched healthy controls. Participants underwent a postural geometric measurement in upright standing. 3-D motion analysis generated the coordinates of skeletal structures from anatomical landmarks. Participants with COPD completed questionnaires related to pain. Postural stability measures of center of pressure in the anteroposterior (A/P) and mediolateral (M/L) directions, spinal alignment, thoracic kyphosis, scapula and sternal orientation were completed. RESULTS: Twenty-one participants with COPD and 21 matched controls completed the study. The method of postural stability and alignment demonstrated excellent reliability in both groups (all ICC > 0.75). Those with COPD had a trend towards a greater center of pressure M/L sway compared to controls (mean 4.3 cm vs 2.9 cm), with no difference in center of pressure A/P sway. Thoracic kyphosis was greater in COPD (51.8 degrees vs 39.1 degrees, p = 0.001), but there was no difference in spinal alignment (p > 0.05). Those with COPD had an increase in left (p = 0.003) and right (p = 0.002) scapula protraction. Increased thoracic kyphosis and altered scapula position were unrelated to back pain in COPD (all p > 0.05). CONCLUSIONS: Postural deviations are evident in COPD, but the small number of those with pain limited analysis of the association between postural deviations and pain.