Rib Rotation

Rib external rotation involves the ribs twisting posteriorly, expanding outward, moving apart, and becoming slightly straighter. Rib external rotation is associated with expansion, while rib internal rotation is associated with compression. Rib internal rotation narrows and compresses the rib cage as the ribs become more curved, move downward, and rotate anteriorly as a unit. Pump-handle, bucket-handle, and posterior expansion motions combine to create multidirectional rib cage expansion during inhalation. Rib internal rotation supports exhalation by compressing the ventral cavity and helping air leave the body.