Relationship between costovertebral joint kinematics and lung volume in supine humans

• A detailed analysis of costovertebral joint kinematics is presented.
• No linear correlation was found between lung volumes and CVJ kinematics.
• Ranges-of-motion decrease gradually with increasing CVJ level.
• Rib displacements are reduced at lung volumes above 50% of the inspiratory capacity.
• Axes of rotations of the ribs are similarly oriented for all rib levels.

This study investigates the relationship between the motion of the first ten costovertebral joints (CVJ) and lung volume over the inspiratory capacity (IC) using detailed kinematic analysis in a sample of 12 asymptomatic subjects.Retrospective codified spiral-CT data obtained at total lung capacity (TLC), middle of inspiratory capacity (MIC) and at functional residual capacity (FRC) were analysed. CVJ 3D kinematics were processed using previously-published methods. We tested the influence of the side, CVJ level and lung volume on CVJ kinematics. In addition, the correlations between anthropologic/pulmonary variables and CVJ kinematics were analysed.No linear correlation was found between lung volumes and CVJ kinematics. Major findings concerning 3D kinematics can be summarized as follows: 1) Ranges-of-motion decrease gradually with increasing CVJ level; 2) rib displacements are significantly reduced at lung volumes above the MIC and do not differ between CVJ levels; 3) the axes of rotation of the ribs are similarly oriented for all CVJ levels.