Posture and mobility of the upper body quadrant and pulmonary function in COPD: an exploratory study

Nuno Morais, Joana Cruz, Alda Marques

Background There is limited evidence regarding interactions between pulmonary (dys)function, posture, and mobility of the upper body quadrant in patients with chronic obstructive pulmonary disease (COPD). Objectives This exploratory study aimed to investigate whether postural alignment and mobility of the upper quadrant are related to changes in pulmonary function and compare such variables between patients with COPD and healthy individuals. Method Fifteen patients with COPD (67.93±9.71yrs) and 15 healthy controls (66.80±7.47yrs) participated. Pulmonary function (FEV1, FVC) was assessed with spirometry. Alignment and mobility of the head, thoracic spine, and shoulder were assessed using digital photographs. Pectoralis minor muscle (PmM) length and thoracic excursion were assessed with a measuring tape. Groups were compared and linear regression analyses were used to assess potential relationships between postural and mobility variables and pulmonary function. Results Patients with COPD were more likely to have a forward head position at maximal protraction (28.81±7.30º vs. 35.91±8.56º, p=0.02) and overall mobility of the head (21.81±10.42º vs. 13.40±7.84º, p=0.02) and a smaller range of shoulder flexion (136.71±11.91º vs. 149.08±11.58º, p=0.01) than controls. Patients' non-dominant PmM length and maximal head protraction were predictors of FEV1 (r2adjusted=0.34). These variables, together with the upper thoracic spine at maximal flexion and thoracic kyphosis at maximal extension, were predictors of FVC (r2adjusted=0.68). Conclusion Our findings suggest that impaired pulmonary function is associated with muscle length and mobility adaptations. Further studies are needed to understand the underlying mechanisms and clinical value of these relationships.