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Updated: Aug 14, 2026

Evaluation of Respiratory Muscle Activation Using Respiratory Motor Control Assessment (RMCA) in Individuals with Chronic Spinal Cord Injury
Published on: July 19, 2013
[The respiratory muscles and the thoracic cage during respiration at rest]
1Service de Pneumologie, Hôpital universitaire Erasme, Université libre de Bruxelles.
Abstract:
Even though the diaphragm is the primary respiratory muscle in humans, resting breathing involves other muscles. The diaphragm acting alone is not able to expand the entire rib cage. The expansion of the upper rib cage results from the combined actions of the scalene and intercostal muscles, in particular the parasternals. The external intercostals and the levator costae might constitute a reserve system that is called into action when the load placed on the inspiratory pump is increased.
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