Thoracic kyphosis, rib mobility, and lung volumes in normal women and women with osteoporosis.

ABSTRACT

STUDY DESIGN: Lung volumes and rib mobility were measured in 15 women with kyphosis resulting from spinal osteoporosis and in 15 healthy women. OBJECTIVES: The study first sought to determine the relationship between thoracic kyphosis and rib mobility and then sought to determine the effect of kyphosis and associated changes in rib mobility on respiratory function. SUMMARY OF BACKGROUND DATA Spinal deformity in ankylosing spondylitis and scoliosis is associated with alterations in respiratory function. The effect of thoracic kyphosis on respiratory mechanics has not been investigated in an osteoporotic population. METHODS: Lung volumes were measured using a spirometer, and rib mobility, during maximal inspiratory and expiratory maneuvers, was monitored with four motion sensors placed anteriorly, posteriorly, and laterally on the thorax. RESULTS: Vital capacity, inspiratory capacity, total lung capacity, and lateral expansion of the thorax were lower in the osteoporotic group (P < 0.05). There was a significant negative correlation between kyphosis angle and inspiratory capacity, vital capacity, and lateral expansion of the thorax. CONCLUSIONS: Lung volumes and rib mobility were significantly impaired in women with thoracic kyphosis.