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Mechanics of the Respiratory Muscles

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Abstract

This article examines the mechanics of the muscles that drive expansion or contraction of the chest wall during breathing. The diaphragm is the main inspiratory muscle. When its muscle fibers are activated in isolation, they shorten, the dome of the diaphragm descends, pleural pressure (Ppl) falls, and abdominal pressure (Pab) rises. As a result, the ventral abdominal wall expands, but a large fraction of the rib cage contracts. Expansion of the rib cage during inspiration is produced by the external intercostals in the dorsal portion of the rostral interspaces, the intercartilaginous portion of the internal intercostals (the so‐called parasternal intercostals), and, in humans, the scalenes. By elevating the ribs and causing an additional fall in Ppl, these muscles not only help the diaphragm expand the chest wall and the lung, but they also increase the load on the diaphragm and reduce the shortening of the diaphragmatic muscle fibers. The capacity of the diaphragm to generate pressure is therefore enhanced. In contrast, during expiratory efforts, activation of the abdominal muscles produces a rise in Pab that leads to a cranial displacement of the diaphragm into the pleural cavity and a rise in Ppl. Concomitant activation of the internal interosseous intercostals in the caudal interspaces and the triangularis sterni during such efforts contracts the rib cage and helps the abdominal muscles deflate the lung. © 2011 American Physiological Society. Compr Physiol 1:1273‐1300, 2011.

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Figure 1. Figure 1.

Coronal section of the human chest wall at end expiration. The costal diaphragmatic fibers run mainly cranially from their insertions on the lower ribs and are directly apposed to the inner aspect of the lower rib cage (zone of apposition). Reproduced, with permission, from De Troyer A, Loring SH. Actions of the respiratory muscles. In: Roussos C, editor. The Thorax (2nd ed), Vol. 85. New York: Marcel Dekker, 1995, pp. 535‐563).

Figure 2. Figure 2.

Respiratory displacements of the rib cage. (A) diagram of a typical thoracic vertebra and a pair of ribs (viewed from above). Each rib articulates with both the body and the transverse process of the vertebra (closed circles) and is bound to it by strong ligaments (right). The motion of the rib, therefore, occurs primarily through a rotation around the axis defined by these articulations (solid line and double arrow‐head). (B) and (C) ventral and lateral views, respectively, of the rib at end expiration (solid lines) and end inspiration (dotted lines). When the rib becomes more horizontal in inspiration, the transverse (B) and the anteroposterior (C) diameter of the rib cage increase (small arrows), and the sternum is displaced ventrally (vertical line in C). Reproduced, with permission, from De Troyer A. Respiratory muscle function. In: Shoemaker WC, Ayres SM, Grenvik A, Holbrook PR, editors. Textbook of Critical Care. W.B. Saunders, 2000, pp. 1172‐1184).

Figure 3. Figure 3.

Mean ± SE changes in airway opening pressure (ΔPao) and abdominal pressure (ΔPab) obtained from six dogs during isolated, bilateral stimulation of the phrenic nerves at five different lung volumes from FRC (transrespiratory pressure = 0 cmH2O) to TLC (transrespiratory pressure = 30 cmH2O). All stimulations were performed while the endotracheal tube was occluded. The capacity of the diaphragm to generate pressure, in particular pleural pressure, decreases markedly with increasing lung volume. Reproduced, with permission, from ref. ).

Figure 4. Figure 4.

Relationship between transdiaphragmatic pressure (Pdi) and diaphragm muscle length during isolated, supramaximal phrenic nerve stimulation at different lung volumes. The dashed line in the main panel is the aggregate relationship obtained for the costal and crural portions of the canine diaphragm in vivo by Road et al. , and the closed circles are the mean ± SE values obtained from six dogs (same animals as in Figure ) during phrenic nerve stimulation at increasing lung volumes from FRC (top circle) to TLC (bottom circle). Muscle length was measured by computed tomography and is expressed as a percentage of muscle length during relaxation at FRC (LFRC). Note that the data point obtained at FRC is close to the length‐tension relationship of Road et al., but the data points obtained at high lung volumes lay well below the curve. Data in the inset are the mean values obtained before (closed circles) and after (open circle; bars, ± SE) bilateral pneumothorax in a subset of four animals. (Redrawn, with permission, from ref. ).

Figure 5. Figure 5.

Graphical representation of the effect of inflation on the pressure developed by the diaphragm. The continuous lines are the Pdi‐length relationships for the maximally active and the passive diaphragm, and the dashed lines are the load lines describing the load imposed by the lung and chest wall on the diaphragm during isolated contraction at FRC and during isolated contraction at TLC. Pdi is expressed as a fraction of the maximal value, and muscle length is expressed as a fraction of optimal length (Lo). The pressure developed by the diaphragm during phrenic nerve stimulation at a given lung volume is given by the intersection (closed circle) of the load line with the maximally active Pdi‐length curve. Reproduced, with permission, from ref. ).

Figure 6. Figure 6.

Graphical analysis of the pressure generated by the diaphragm in the presence of ascites. The continuous lines describing the Pdi‐length relationships for the maximally active and the passive diaphragm, and the dashed line describing the load line for the isolated diaphragm in the control condition are the same as those in Figure . The thin solid lines are the two load lines for the diaphragm in the presence of moderate and severe ascites. With moderate ascites, the relaxed diaphragm lengthens and the elastance of the abdomen increases, so that the load line is displaced upward and is more steep. As a result, the diaphragm during phrenic nerve stimulation shortens less and generates a larger pressure (closed triangle). With severe ascites, the load line is further displaced upward and still more steep, but the radius of diaphragm curvature during phrenic stimulation increases. Consequently, the active diaphragm is even longer, but the pressure generated (closed square) is smaller than anticipated on the basis of muscle length alone (open square).

Figure 7. Figure 7.

Contours of the diaphragm seen on anteroposterior radiographs in a dog during relaxation at FRC, during isolated tetanic stimulation of the right phrenic nerve (dashed line), and during combined stimulation of the left and right phrenic nerves. Stimulation frequency = 50 Hz. The two short bars on each contour correspond to the junctions of the muscle fibers with the central tendon and show the lateral shift of the tendon (and the mediastinum) during unilateral phrenic nerve stimulation. The surface area (volume) swept by the diaphragm during simultaneous contraction of the right and left hemidiaphragms is more than twice that swept when the right hemidiaphragm contracts in isolation.

Figure 8. Figure 8.

Diagram illustrating the actions of the intercostal muscles, as proposed by Hamberger . The two bars oriented obliquely in each panel represent two adjacent ribs. The external and internal (interosseous) intercostal muscles are depicted as single bundles, and the torques acting on the ribs during contraction of these muscles are represented by arrows. When the external intercostal contracts (A), the torque acting on the lower rib is greater than that acting on the upper rib; the opposite is true when the internal intercostal contracts (B). Reproduced, with permission, from ref. ).

Figure 9. Figure 9.

Maximal respiratory effects of the canine external (A) and internal interosseous (B) intercostal muscles in the dorsal third, middle third, and ventral third of the even‐numbered interspaces (both sides of the sternum). The respiratory effects of the medial portion of the parasternal intercostals in interspaces 2, 4, 6, and 8 are also shown. Reproduced with permission from ref. ).

Figure 10. Figure 10.

Effects of rib curvature on the net moment exerted by an intercostal muscle. (A) plan form of a typical rib in the dog and its axis of rotation (bold vector). At point a, the distances between the points of attachment of an intercostal muscle on the lower and upper ribs and the axes of rotation are different, and the muscle exerts a net moment on the ribs. At point b, however, the distances between the points of attachment of an intercostal muscle on the lower and upper ribs and the axes of rotation of the ribs are equal, and the muscle exerts no net moment. Thus the net moment exerted by the muscle depends on the angular position (θ) around the rib, as shown in (B). The external intercostal muscle (continuous line) has the greatest inspiratory moment in the dorsal portion of the rib cage (θ between 15 and 60°); this inspiratory moment then decreases as one moves around the rib cage (θ between 60 and 120°) and is reversed into an expiratory moment in the vicinity of the sternum (θ > 120°). The internal intercostal muscle (dashed line in B) shows a similar gradient in expiratory moment. Reproduced, with permission, from ref. ).

Figure 11. Figure 11.

Effect on the lung of external loading of individual rib pairs in the cranial direction. Data are the mean ± SE values of the changes in airway opening pressure (ΔPao) per unit force (F) on the ribs obtained from seven animals. At FRC (closed circles), ΔPao /F increases from the second to the fifth rib pair and then decreases continuously to the eleventh rib pair. ΔPao /F for ribs 2 to 8, however, decreases markedly when lung volume is passively increased from FRC to 10 cmH2O (open circles) and 20 cmH2O (open triangles) transrespiratory pressure. Reproduced, with permission, from ref. .

Figure 12. Figure 12.

Patterns of rib displacement produced by the external and parasternal intercostals in the dog. In the animal in (A), the parasternal intercostals in interspaces 1 to 8 were denervated on both sides of the sternum; in the animal in (B), the parasternal intercostals were intact but the external intercostals in interspaces 1 to 8 were excised. Both animals had complete diaphragmatic paralysis. The dashed line in each panel is the trajectory of the ribs during passive inflation (relaxation), and the solid line with the arrowhead corresponds to a spontaneous inspiration. Reproduced, with permission, from ref. .

Figure 13. Figure 13.

Maximal inspiratory effects of the parasternal intercostal and external intercostal muscles in the even‐numbered interspaces in dogs (A) and in humans (B). Redrawn from ref , with permission.

Figure 14. Figure 14.

Effects of inflation on the pressure‐generating ability of the inspiratory intercostals. The closed circles are the mean ± SE values of ΔPao obtained from 19 dogs during isolated, tetanic stimulation of the inspiratory (and expiratory) intercostals at different lung volumes, as reported by DiMarco et al. . The open circles are the mean ± SE values of ΔPao obtained from 9 dogs during spontaneous contraction of the parasternal intercostals alone . Similar to the diaphragm, the pressure‐generating ability of the inspiratory intercostals decreases with increasing lung volume. Reproduced with permission from ref. .

Figure 15. Figure 15.

Dorsal view of the spine and one rib in its position at FRC and its position at 20 cmH2O transrespiratory pressure. Because the rib at FRC is slanted caudally, it moves both cranially (Xr) and outward (Yr) during cranial loading. However, at 20 cmH2O transrespiratory pressure, the rib is almost horizontal. Therefore, loading the rib causes a cranial displacement with little or no outward displacement. Reproduced with permission from ref. .

Figure 16. Figure 16.

Pattern of rib cage motion during mechanical ventilation (left) and during spontaneous breathing (right) in a quadriplegic subject with a traumatic transection of the upper cervical cord (C1). Each panel shows, from top to bottom, the respiratory changes in anteroposterior (AP) diameter of the lower rib cage, the changes in AP diameter of the upper rib cage, the changes in transverse diameter of the lower rib cage, and the changes in xiphi‐pubic distance. Upward deflections correspond to an increase in diameter or an increase in xiphi‐pubic distance (i.e., a cranial displacement of the sternum); I indicates the duration of inspiration. All rib cage diameters and the xiphi‐pubic distance increase in phase during mechanical inflation. When the sternomastoids contract forcefully during spontaneous inspiration, however, the xiphi‐pubic distance and the upper rib cage AP diameter increase proportionately more than the lower rib cage AP diameter, and the lower rib cage transverse diameter then decreases. Reproduced, with permission, from De Troyer A. Mechanics of the chest wall muscles. In: Miller AD, Bianchi AL, Bishop B, editors. Neural control of the respiratory muscles, CRC Press, Inc., 1996, pp. 59–73.



Figure 1.

Coronal section of the human chest wall at end expiration. The costal diaphragmatic fibers run mainly cranially from their insertions on the lower ribs and are directly apposed to the inner aspect of the lower rib cage (zone of apposition). Reproduced, with permission, from De Troyer A, Loring SH. Actions of the respiratory muscles. In: Roussos C, editor. The Thorax (2nd ed), Vol. 85. New York: Marcel Dekker, 1995, pp. 535‐563).



Figure 2.

Respiratory displacements of the rib cage. (A) diagram of a typical thoracic vertebra and a pair of ribs (viewed from above). Each rib articulates with both the body and the transverse process of the vertebra (closed circles) and is bound to it by strong ligaments (right). The motion of the rib, therefore, occurs primarily through a rotation around the axis defined by these articulations (solid line and double arrow‐head). (B) and (C) ventral and lateral views, respectively, of the rib at end expiration (solid lines) and end inspiration (dotted lines). When the rib becomes more horizontal in inspiration, the transverse (B) and the anteroposterior (C) diameter of the rib cage increase (small arrows), and the sternum is displaced ventrally (vertical line in C). Reproduced, with permission, from De Troyer A. Respiratory muscle function. In: Shoemaker WC, Ayres SM, Grenvik A, Holbrook PR, editors. Textbook of Critical Care. W.B. Saunders, 2000, pp. 1172‐1184).



Figure 3.

Mean ± SE changes in airway opening pressure (ΔPao) and abdominal pressure (ΔPab) obtained from six dogs during isolated, bilateral stimulation of the phrenic nerves at five different lung volumes from FRC (transrespiratory pressure = 0 cmH2O) to TLC (transrespiratory pressure = 30 cmH2O). All stimulations were performed while the endotracheal tube was occluded. The capacity of the diaphragm to generate pressure, in particular pleural pressure, decreases markedly with increasing lung volume. Reproduced, with permission, from ref. ).



Figure 4.

Relationship between transdiaphragmatic pressure (Pdi) and diaphragm muscle length during isolated, supramaximal phrenic nerve stimulation at different lung volumes. The dashed line in the main panel is the aggregate relationship obtained for the costal and crural portions of the canine diaphragm in vivo by Road et al. , and the closed circles are the mean ± SE values obtained from six dogs (same animals as in Figure ) during phrenic nerve stimulation at increasing lung volumes from FRC (top circle) to TLC (bottom circle). Muscle length was measured by computed tomography and is expressed as a percentage of muscle length during relaxation at FRC (LFRC). Note that the data point obtained at FRC is close to the length‐tension relationship of Road et al., but the data points obtained at high lung volumes lay well below the curve. Data in the inset are the mean values obtained before (closed circles) and after (open circle; bars, ± SE) bilateral pneumothorax in a subset of four animals. (Redrawn, with permission, from ref. ).



Figure 5.

Graphical representation of the effect of inflation on the pressure developed by the diaphragm. The continuous lines are the Pdi‐length relationships for the maximally active and the passive diaphragm, and the dashed lines are the load lines describing the load imposed by the lung and chest wall on the diaphragm during isolated contraction at FRC and during isolated contraction at TLC. Pdi is expressed as a fraction of the maximal value, and muscle length is expressed as a fraction of optimal length (Lo). The pressure developed by the diaphragm during phrenic nerve stimulation at a given lung volume is given by the intersection (closed circle) of the load line with the maximally active Pdi‐length curve. Reproduced, with permission, from ref. ).



Figure 6.

Graphical analysis of the pressure generated by the diaphragm in the presence of ascites. The continuous lines describing the Pdi‐length relationships for the maximally active and the passive diaphragm, and the dashed line describing the load line for the isolated diaphragm in the control condition are the same as those in Figure . The thin solid lines are the two load lines for the diaphragm in the presence of moderate and severe ascites. With moderate ascites, the relaxed diaphragm lengthens and the elastance of the abdomen increases, so that the load line is displaced upward and is more steep. As a result, the diaphragm during phrenic nerve stimulation shortens less and generates a larger pressure (closed triangle). With severe ascites, the load line is further displaced upward and still more steep, but the radius of diaphragm curvature during phrenic stimulation increases. Consequently, the active diaphragm is even longer, but the pressure generated (closed square) is smaller than anticipated on the basis of muscle length alone (open square).



Figure 7.

Contours of the diaphragm seen on anteroposterior radiographs in a dog during relaxation at FRC, during isolated tetanic stimulation of the right phrenic nerve (dashed line), and during combined stimulation of the left and right phrenic nerves. Stimulation frequency = 50 Hz. The two short bars on each contour correspond to the junctions of the muscle fibers with the central tendon and show the lateral shift of the tendon (and the mediastinum) during unilateral phrenic nerve stimulation. The surface area (volume) swept by the diaphragm during simultaneous contraction of the right and left hemidiaphragms is more than twice that swept when the right hemidiaphragm contracts in isolation.



Figure 8.

Diagram illustrating the actions of the intercostal muscles, as proposed by Hamberger . The two bars oriented obliquely in each panel represent two adjacent ribs. The external and internal (interosseous) intercostal muscles are depicted as single bundles, and the torques acting on the ribs during contraction of these muscles are represented by arrows. When the external intercostal contracts (A), the torque acting on the lower rib is greater than that acting on the upper rib; the opposite is true when the internal intercostal contracts (B). Reproduced, with permission, from ref. ).



Figure 9.

Maximal respiratory effects of the canine external (A) and internal interosseous (B) intercostal muscles in the dorsal third, middle third, and ventral third of the even‐numbered interspaces (both sides of the sternum). The respiratory effects of the medial portion of the parasternal intercostals in interspaces 2, 4, 6, and 8 are also shown. Reproduced with permission from ref. ).



Figure 10.

Effects of rib curvature on the net moment exerted by an intercostal muscle. (A) plan form of a typical rib in the dog and its axis of rotation (bold vector). At point a, the distances between the points of attachment of an intercostal muscle on the lower and upper ribs and the axes of rotation are different, and the muscle exerts a net moment on the ribs. At point b, however, the distances between the points of attachment of an intercostal muscle on the lower and upper ribs and the axes of rotation of the ribs are equal, and the muscle exerts no net moment. Thus the net moment exerted by the muscle depends on the angular position (θ) around the rib, as shown in (B). The external intercostal muscle (continuous line) has the greatest inspiratory moment in the dorsal portion of the rib cage (θ between 15 and 60°); this inspiratory moment then decreases as one moves around the rib cage (θ between 60 and 120°) and is reversed into an expiratory moment in the vicinity of the sternum (θ > 120°). The internal intercostal muscle (dashed line in B) shows a similar gradient in expiratory moment. Reproduced, with permission, from ref. ).



Figure 11.

Effect on the lung of external loading of individual rib pairs in the cranial direction. Data are the mean ± SE values of the changes in airway opening pressure (ΔPao) per unit force (F) on the ribs obtained from seven animals. At FRC (closed circles), ΔPao /F increases from the second to the fifth rib pair and then decreases continuously to the eleventh rib pair. ΔPao /F for ribs 2 to 8, however, decreases markedly when lung volume is passively increased from FRC to 10 cmH2O (open circles) and 20 cmH2O (open triangles) transrespiratory pressure. Reproduced, with permission, from ref. .



Figure 12.

Patterns of rib displacement produced by the external and parasternal intercostals in the dog. In the animal in (A), the parasternal intercostals in interspaces 1 to 8 were denervated on both sides of the sternum; in the animal in (B), the parasternal intercostals were intact but the external intercostals in interspaces 1 to 8 were excised. Both animals had complete diaphragmatic paralysis. The dashed line in each panel is the trajectory of the ribs during passive inflation (relaxation), and the solid line with the arrowhead corresponds to a spontaneous inspiration. Reproduced, with permission, from ref. .



Figure 13.

Maximal inspiratory effects of the parasternal intercostal and external intercostal muscles in the even‐numbered interspaces in dogs (A) and in humans (B). Redrawn from ref , with permission.



Figure 14.

Effects of inflation on the pressure‐generating ability of the inspiratory intercostals. The closed circles are the mean ± SE values of ΔPao obtained from 19 dogs during isolated, tetanic stimulation of the inspiratory (and expiratory) intercostals at different lung volumes, as reported by DiMarco et al. . The open circles are the mean ± SE values of ΔPao obtained from 9 dogs during spontaneous contraction of the parasternal intercostals alone . Similar to the diaphragm, the pressure‐generating ability of the inspiratory intercostals decreases with increasing lung volume. Reproduced with permission from ref. .



Figure 15.

Dorsal view of the spine and one rib in its position at FRC and its position at 20 cmH2O transrespiratory pressure. Because the rib at FRC is slanted caudally, it moves both cranially (Xr) and outward (Yr) during cranial loading. However, at 20 cmH2O transrespiratory pressure, the rib is almost horizontal. Therefore, loading the rib causes a cranial displacement with little or no outward displacement. Reproduced with permission from ref. .



Figure 16.

Pattern of rib cage motion during mechanical ventilation (left) and during spontaneous breathing (right) in a quadriplegic subject with a traumatic transection of the upper cervical cord (C1). Each panel shows, from top to bottom, the respiratory changes in anteroposterior (AP) diameter of the lower rib cage, the changes in AP diameter of the upper rib cage, the changes in transverse diameter of the lower rib cage, and the changes in xiphi‐pubic distance. Upward deflections correspond to an increase in diameter or an increase in xiphi‐pubic distance (i.e., a cranial displacement of the sternum); I indicates the duration of inspiration. All rib cage diameters and the xiphi‐pubic distance increase in phase during mechanical inflation. When the sternomastoids contract forcefully during spontaneous inspiration, however, the xiphi‐pubic distance and the upper rib cage AP diameter increase proportionately more than the lower rib cage AP diameter, and the lower rib cage transverse diameter then decreases. Reproduced, with permission, from De Troyer A. Mechanics of the chest wall muscles. In: Miller AD, Bianchi AL, Bishop B, editors. Neural control of the respiratory muscles, CRC Press, Inc., 1996, pp. 59–73.

References
 1. Abe T, Kusuhara N, Yoshimura N, Tomita T, Easton PA. Differential respiratory activity of four abdominal muscles in humans. J Appl Physiol 80: 1379‐1379, 1996.
 2. Agostoni E, Mognoni P, Torri G, Agostoni A. Static features of the passive rib cage and diaphragm‐abdomen. J Appl Physiol 20: 1187‐1187, 1965.
 3. Bainton CR, Kirkwood PA, Sears TA. On the transmission of the stimulating effects of carbon dioxide to the muscles of respiration. J Physiol 280: 249‐249, 1978.
 4. Bellemare F, Bigland‐Ritchie B, Woods JJ. Contractile properties of the human diaphragm in vivo. J Appl Physiol 61: 1153‐1153, 1986.
 5. Bolser DC, Reier PJ, Davenport PW. Responses of the anterolateral abdominal muscles during cough and expiratory threshold loading in the cat. J Appl Physiol 88: 1207‐1207, 2000.
 6. Boriek AM, Black B, Hubmayr R, Wilson TA. Length and curvature of the dog diaphragm. J Appl Physiol 101: 794‐794, 2006.
 7. Boriek AM, Hwang W, Trinh L, Rodarte JR. Shape and tension distribution of the active canine diaphragm. Am J Physiol Regul Integr Comp Physiol 288: R1021‐R1027, 2005.
 8. Boriek AM, Kelly NG, Rodarte JR, Wilson TA. Biaxial constitutive relations for the passive canine diaphragm. J Appl Physiol 89: 2187‐2187, 2000.
 9. Boriek AM, Liu S, Rodarte JR. Costal diaphragm curvature in the dog. J Appl Physiol 75: 527‐527, 1993.
 10. Boriek AM, Rodarte JR. Effects of transverse fiber stiffness and central tendon on displacement and shape of a simple diaphragm model. J Appl Physiol 82: 1626‐1626, 1997.
 11. Boriek AM, Rodarte JR, Margulies SS. Zone of apposition in the passive diaphragm of the dog. J Appl Physiol 81: 1929‐1929, 1996.
 12. Boriek AM, Rodarte JR, Wilson TA. Kinematics and mechanics of midcostal diaphragm of dog. J Appl Physiol 83: 1068‐1068, 1997.
 13. Botha GSM. The anatomy of phrenic nerve termination and the motor innervation of the diaphragm. Thorax 12: 50‐50, 1957.
 14. Brancatisano A, Amis TC, Tully A, Kelly WT, Engel LA. Regional distribution of blood flow within the diaphragm. J Appl Physiol 71: 583‐583, 1991.
 15. Campbell EJM. The role of the scalene and sternomastoid muscles in breathing in normal subjects. An electromyographic study. J Anat 89: 378‐378, 1955.
 16. Campbell EJM, Green JH. The behavior of the abdominal muscles and the intra‐abdominal pressure during quiet breathing and increased pulmonary ventilation. A study in man. J Physiol 127: 423‐423, 1955.
 17. Cappello M, De Troyer A. Interaction between left and right intercostal muscles in airway pressure generation. J Appl Physiol 88: 817‐817, 2000.
 18. Cappello M, De Troyer A. On the respiratory function of the ribs. J Appl Physiol 92: 1642‐1642, 2002.
 19. Cappello M, De Troyer A. Role of rib cage elastance in the coupling between the abdominal muscles and the lung. J Appl Physiol 97: 85‐85, 2004.
 20. Celli BR, Rassulo J, Corral R. Ventilatory muscle dysfunction in patients with bilateral idiopathic diaphragmatic paralysis: Reversal by intermittent external negative pressure ventilation. Am Rev Respir Dis 136: 1276‐1276, 1987.
 21. Close RI. Dynamic properties of mammalian skeletal muscles. Physiol Rev 52: 129‐129, 1972.
 22. Danon J, Druz WS, Goldberg NB, Sharp JT. Function for the isolated paced diaphragm and the cervical accessory muscles in C1 quadriplegics. Am Rev Respir Dis 119: 909‐909, 1979.
 23. D'Angelo E, Prandi E, Bellemare F. Mechanics of the abdominal muscles in rabbits and dogs. Respir Physiol 97: 275‐275, 1994.
 24. D'Angelo E, Prandi E, D'Angelo E, Pecchiari M. Lung‐deflating ability of rib cage and abdominal muscles in rabbits. Respir Physiol Neurobiol 135: 17‐17, 2003.
 25. D'Angelo E, Prandi E, Robatto F, Petitjean M, Bellemare F. Insertional action of the abdominal muscles in rabbits and dogs. Respir Physiol 104: 147‐147, 1996.
 26. D'Angelo E, Sant'Ambrogio G. Direct action of contracting diaphragm on the rib cage in rabbits and dogs. J Appl Physiol 36: 715‐715, 1974a.
 27. D'Angelo E, Sant'Ambrogio G, Agostoni E. Effect of diaphragm activity or paralysis on distribution of pleural pressure. J Appl Physiol 37: 311‐311, 1974b.
 28. Da Silva KMC, Sayers BMA, Sears TA, Stagg DT. The changes in configuration of the rib cage and abdomen during breathing in the anaesthetized cat. J Physiol 266: 499‐499, 1977.
 29. Decramer M, Jiang TX, Demedts M. Effects of acute hyperinflation on chest wall mechanics in dogs. J Appl Physiol 63: 1493‐1493, 1987.
 30. Delhez L. Contribution électromyographique à l’étude de la mécanique et du contrôle nerveux des mouvements respiratoires de l'homme. Belgium: Vaillant‐Carmanne, Liège, 1974.
 31. De Troyer A. Mechanical role of the abdominal muscles in relation to posture. Respir Physiol 53: 341‐341, 1983.
 32. De Troyer A. Mechanics of the chest wall muscles. In: Miller AD, Bianchi AL, Bishop BP, editors. Neural control of the respiratory muscles, CRC Press, Inc., 1996, pp. 59‐73.
 33. De Troyer A. Respiratory muscle function. In: Shoemaker WC, Ayres SM, Grenvik A, Holbrook PR, editors.Textbook of Critical Care. W.B. Saunders, 2000, pp. 1172‐1184.
 34. De Troyer A. Impact of diaphragmatic contraction on the stiffness of the canine mediastinum. J Appl Physiol 105: 887‐887, 2008.
 35. De Troyer A, Cappello M, Brichant JF. Do canine scalene and sternomastoid muscles play a role in breathing? J Appl Physiol 76: 242‐242, 1994.
 36. De Troyer A, Cappello M, Leduc D, Gevenois PA. Role of the mediastinum in the mechanics of the canine diaphragm. J Appl Physiol 109: 27‐27, 2010.
 37. De Troyer A, Cappello M, Meurant N, Scillia P. Synergism between the canine left and right hemidiaphragms. J Appl Physiol 94: 1757‐1757, 2003.
 38. De Troyer A, Estenne M. Coordination between rib cage muscles and diaphragm during quiet breathing in humans. J Appl Physiol 57: 899‐899, 1984.
 39. De Troyer A, Estenne M, Ninane V. Rib cage mechanics in simulated diaphragmatic paralysis. Am Rev Respir Dis 132: 793‐793, 1985.
 40. De Troyer A, Estenne M, Ninane V, Van Gansbeke D, Gorini M. Transversus abdominis muscle function in humans. J Appl Physiol 68: 1010‐1010, 1990.
 41. De Troyer A, Estenne M, Vincken W. Rib cage motion and muscle use in high tetraplegics. Am Rev Respir Dis 133: 1115‐1115, 1986.
 42. De Troyer A, Farkas GA. Inspiratory function of the levator costae and external intercostal muscles in the dog. J Appl Physiol 67: 2614‐2614, 1989.
 43. De Troyer A, Gilmartin JJ, Ninane V. Abdominal muscle use during breathing in unanesthetized dogs. J Appl Physiol 66: 20‐20, 1989.
 44. De Troyer A, Gorman R, Gandevia SG. Distribution of inspiratory drive to the external intercostal muscles in humans. J Physiol 546: 943‐943, 2003.
 45. De Troyer A, Kelly S. Chest wall mechanics in dogs with acute diaphragm paralysis. J Appl Physiol 53: 373‐373, 1982.
 46. De Troyer A, Kelly S. Action of neck accessory muscles on rib cage in dogs. J Appl Physiol 56: 326‐326, 1984.
 47. De Troyer A, Kirkwood PA, Wilson TA. Respiratory action of the intercostal muscles. Physiol Rev 85: 717‐717, 2005.
 48. De Troyer A, Leduc D. Effect of inflation on the coupling between the ribs and the lung in dogs. J Physiol 555: 481‐481, 2004.
 49. De Troyer A, Leduc D. Effect of diaphragmatic contraction on the action of the canine parasternal intercostals. J Appl Physiol 101: 169‐169, 2006.
 50. De Troyer A, Leduc D. Role of pleural pressure in the coupling between the intercostal muscles and the ribs. J Appl Physiol 102: 2332‐2332, 2007.
 51. De Troyer A, Leduc D, Cappello M, Mine B, Gevenois PA, Wilson TA. Mechanisms of the inspiratory action of the diaphragm during isolated contraction. J Appl Physiol 107: 1736‐1736, 2009.
 52. De Troyer A, Legrand A. Inhomogenous activation of the parasternal intercostals during breathing. J Appl Physiol 79: 55‐55, 1995.
 53. De Troyer A, Legrand A. Mechanical advantage of the canine triangularis sterni. J Appl Physiol 84: 562‐562, 1998.
 54. De Troyer A, Legrand A, Gevenois PA, Wilson TA. Mechanical advantage of the human parasternal intercostal and triangularis sterni muscles. J Physiol 513: 915‐915, 1998.
 55. De Troyer A, Legrand A, Wilson TA. Rostrocaudal gradient of mechanical advantage in the parasternal intercostal muscles of the dog. J Physiol 495: 239‐239, 1996.
 56. De Troyer A, Legrand A, Wilson TA. Respiratory mechanical advantage of the canine external and internal intercostal muscles. J Physiol 518: 283‐283, 1999.
 57. De Troyer A, Loring SH. Actions of the respiratory muscles. In: Roussos C, editor. The Thorax (2nd ed), Vol. 85. New York: Marcel Dekker, 1995, pp. 535‐563.
 58. De Troyer A, Ninane V. Triangularis sterni: A primary muscle of breathing in the dog. J Appl Physiol 60: 14‐14, 1986.
 59. De Troyer A, Sampson M, Sigrist S, Kelly S. How the abdominal muscles act on the rib cage. J Appl Physiol 54: 465‐465, 1983.
 60. De Troyer A, Sampson M, Sigrist S, Macklem PT. Action of costal and crural parts of the diaphragm on the rib cage in dog. J Appl Physiol 53: 30‐30, 1982.
 61. De Troyer A, Wilson TA. The canine parasternal and external intercostal muscles drive the ribs differently. J Physiol 523: 799‐799, 2000.
 62. De Troyer A, Wilson TA. Coupling between the ribs and the lung in dogs. J Physiol 540: 231‐231, 2002.
 63. De Troyer A, Wilson TA. Effect of acute inflation on the mechanics of the inspiratory muscles. J Appl Physiol 107: 315‐315, 2009.
 64. DiMarco AF, Romaniuk JR, Supinski GS. Mechanical action of the interosseous intercostal muscles as a function of lung volume. Am Rev Respir Dis 142: 1041‐1041, 1990.
 65. DiMarco AF, Romaniuk JR, Supinski GS. Parasternal and external intercostal responses to various respiratory maneuvers. J Appl Physiol 73: 979‐979, 1992.
 66. DiMarco AF, Supinski GS, Budzinska K. Inspiratory muscle interaction in the generation of changes in airway pressure. J Appl Physiol 66: 2573‐2573, 1989.
 67. Duchenne GB. Physiologie des Mouvements. Paris: Baillière, 1967.
 68. Easton PA, Fitting JW, Arnoux R, Guerraty A, Grassino AE. Recovery of diaphragm function after laparotomy and chronic sonomicrometer implantation. J Appl Physiol 66: 613‐613, 1989.
 69. Estenne M, De Troyer A. Relationship between respiratory muscle electromyogram and rib cage motion in tetraplegia. Am Rev Respir Dis 132: 53‐53, 1985.
 70. Estenne M, Pinet C, De Troyer A. Abdominal muscle strength in patients with tetraplegia. Am J Respir Crit Care Med 161: 707‐707, 2000.
 71. Estenne M, Yernault JC, De Troyer A. Rib cage and diaphragm‐abdomen compliance in humans: Effects of age and posture. J Appl Physiol 59: 1842‐1842, 1985.
 72. Evanich MJ, Franco MJ, Lourenco RV. Force output of the diaphragm as a function of phrenic nerve firing and lung volume. J Appl Physiol 35: 208‐208, 1973.
 73. Farkas GA. Mechanical properties of respiratory muscles in primates. Respir Physiol 86: 41‐41, 1991.
 74. Farkas GA, Decramer M, Rochester DF, De Troyer A. Contractile properties of intercostal muscles and their functional significance. J Appl Physiol 59: 528‐528, 1985.
 75. Farkas GA, Rochester DF. Functional characteristics of canine costal and crural diaphragm. J Appl Physiol 65: 2253‐2253, 1988a.
 76. Farkas GA, Rochester DF. Characteristics and functional significance of canine abdominal muscles. J Appl Physiol 65: 2427‐2427, 1988b.
 77. Floyd WF, Silver PHS. Electromyographic study of patterns of activity of the anterior abdominal wall muscles in man. J Anat 84: 132‐132, 1950.
 78. Fournier M, Lewis MI. Functional role and structure of the scalene: An accessory inspiratory muscle in hamster. J Appl Physiol 91: 2436‐2436, 1996.
 79. Gandevia SC, Hudson AL, Gorman RB, Butler JE, De Troyer A. Spatial distribution of inspiratory drive to the parasternal intercostal muscles in humans. J Physiol 573: 263‐263, 2006.
 80. Gandevia SC, Leeper JB, McKenzie DK, De Troyer A. Discharge frequencies of parasternal intercostal and scalene motor units during breathing in normal and COPD subjects. Am J Resp Crit Care Med 153: 622‐622, 1996.
 81. Gandevia SC, McKenzie DK, Plassman BL. Activation of human respiratory muscles during different voluntary manoeuvers. J Physiol 428: 387‐387, 1990.
 82. Gauthier AP, Verbanck S, Estenne M, Segebarth C, Macklem PT, Paiva M. Three‐dimensional reconstruction of the in vivo human diaphragm shape at different lung volumes. J Appl Physiol 76: 495‐495, 1994.
 83. Gilmartin JJ, Ninane V, De Troyer A. Abdominal muscle use during breathing in the anesthetized dog. Respir Physiol 70: 159‐159, 1987.
 84. Greer JJ, Martin TP. Distribution of muscle fiber types and EMG activity in cat intercostal muscles. J Appl Physiol 69: 1208‐1208, 1990.
 85. Hamberger GE. De Respirationis Mechanismo et usu Genuino. Germany: Jena, 1749.
 86. Hershenson MB, Kikuchi Y, Loring SH. Relative strengths of the chest wall muscles. J Appl Physiol 65: 852‐852, 1988.
 87. Higenbottam T, Allen D, Loh L, Clark TJH. Abdominal wall movement in normals and patients with hemidiaphragmatic and bilateral diaphragmatic palsy. Thorax 32: 589‐589, 1977.
 88. Hilaire GG, Nicholls JG, Sears TA. Central and proprioceptive influences on the activity of the levator costae motoneurones in the cat. J Physiol 342: 527‐527, 1983.
 89. Hubmayr RD, Sprung J, Nelson S. Determinants of transdiaphragmatic pressure in dogs. J Appl Physiol 69: 2050‐2050, 1990.
 90. Hudson AL, Gandevia SC, Butler JE. The effect of lung volume on the co‐ordinated recruitment of scalene and sternomastoid muscles in humans. J Physiol 584: 261‐261, 2007.
 91. Hwang JC, Zhou D, St John WM. Characterization of expiratory intercostal activity to triangularis sterni in cats. J Appl Physiol 67: 1518‐1518, 1989.
 92. Hwang W, Carvalho JC, Tarlovsky I, Boriek AM. Passive mechanics of canine internal abdominal muscles. J Appl Physiol 98: 1829‐1829, 2005.
 93. Hwang W, Kelly NG, Boriek AM. Passive mechanics of muscle tendinous junction of canine diaphragm. J Appl Physiol 98: 1328‐1328, 2005.
 94. Jefferson NC, Ogawa T, Necheles H. Trophic effects in the absence of respiratory function of the phrenic nerve. Am J Physiol 193: 563‐563, 1958.
 95. Jiang TX, Deschepper K, Demedts M, Decramer M. Effects of acute hyperinflation on the mechanical effectiveness of the parasternal intercostals. Am Rev Respir Dis 139: 522‐522, 1989.
 96. Johnson RL Jr, Hsia CCW, Takeda SI, Wait JL, Glenny RW. Efficient design of the diaphragm: Distribution of blood flow relative to mechanical advantage. J Appl Physiol 93: 925‐925, 2002.
 97. Kim MJ, Druz WS, Danon J, Machnach W, Sharp JT. Mechanics of the canine diaphragm. J Appl Physiol 41: 369‐369, 1976.
 98. Kirkwood PA, Sears TA, Stagg D, Westgaard RH. The spatial distribution of synchronization of intercostal motoneurones in the cat. J Physiol 327: 137‐137, 1982.
 99. Konno K, Mead J. Measurement of the separate volume changes of rib cage and abdomen during breathing. J Appl Physiol 22: 407‐407, 1967.
 100. Kreitzer SM, Feldman NT, Saunders NA, Ingram RH Jr. Bilateral diaphragmatic paralysis with hypercapnic respiratory failure. Am J Med 65: 89‐89, 1978.
 101. Kyroussis D, Polkey MI, Mills GH, Hughes PD, Moxham J, Green M. Simulation of cough in man by magnetic stimulation of the thoracic nerve roots. Am J Respir Crit Care Med 158: 1696‐1696, 1997.
 102. Landau BR, Akert K, Roberts TS. Studies on the innervation of the diaphragm. J Comp Neurol 119: 1‐1, 1962.
 103. Laroche CM, Carroll N, Moxham J, Green M. Clinical significance of severe isolated diaphragm weakness. Am Rev Respir Dis 138: 862‐862, 1988.
 104. Leduc D, Cappello M, Gevenois PA, De Troyer A. Mechanics of the canine diaphragm in ascites: A CT study. J Appl Physiol 104: 423‐423, 2008.
 105. Leduc D, De Troyer A. The effect of lung inflation on the inspiratory action of the canine parasternal intercostals. J Appl Physiol 100: 585‐585, 2006.
 106. Leduc D, De Troyer A. Dysfunction of the canine respiratory muscle pump in ascites. J Appl Physiol 102: 650‐650, 2007.
 107. Leduc D, De Troyer A. Impact of acute ascites on the action of the canine abdominal muscles. J Appl Physiol 104: 1568‐1568, 2008.
 108. Leevers AM, Road JD. Mechanical response to hyperinflation of the two abdominal muscle layers. J Appl Physiol 66: 2189‐2189, 1989.
 109. Leevers AM, Road JD. Abdominal muscle activity during hypercapnia in awake dogs. J Appl Physiol 77: 1393‐1393, 1994.
 110. Legrand A, Brancatisano A, Decramer M, De Troyer A. Rostrocaudal gradient of electrical activation in the parasternal intercostal muscles of the dog. J Physiol 495: 247‐247, 1996.
 111. Legrand A, De Troyer A. Spatial distribution of external and internal intercostal activity in dogs. J Physiol 518: 291‐291, 1999.
 112. Legrand A, Goldman S, Damhaut P, De Troyer A. Heterogeneity of metabolic activity in the canine parasternal intercostals during breathing. J Appl Physiol 90: 811‐811, 2001.
 113. Legrand A, Majcher M, Joly E, Bonaert A, Gevenois PA. Neuromechanical matching of drive in the scalene muscle in the anesthetized rabbit. J Appl Physiol 107: 741‐741, 2009.
 114. Legrand A, Ninane V, De Troyer A. Mechanical advantage of sternomastoid and scalene muscles in dogs. J Appl Physiol 82: 1517‐1517, 1997.
 115. Legrand A, Schneider E, Gevenois PA, De Troyer A. Respiratory effects of the scalene and sternomastoid muscles in humans. J Appl Physiol 94: 1467‐1467, 2003.
 116. Legrand A, Wilson TA, De Troyer A. Rib cage muscle interaction in airway pressure generation. J Appl Physiol 85: 198‐198, 1998.
 117. Lim J, Gorman RB, Saboisky JP, Gandevia SC, Butler JE. Optimal electrode placement for noninvasive electrical stimulation of human abdominal muscles. J Appl Physiol 102: 1612‐1612, 2007.
 118. Loring SH. Action of human respiratory muscles inferred from finite element analysis of rib cage. J Appl Physiol 72: 1461‐1461, 1992.
 119. Loring SH, Mead J. Abdominal muscle use during quiet breathing and hyperpnea in uninformed subjects. J Appl Physiol 52: 700‐700, 1982a.
 120. Loring SH, Mead J. Action of the diaphragm on the rib cage inferred from a force‐balance analysis. J Appl Physiol 53: 756‐756, 1982b.
 121. Loring SH, Woodbridge JA. Intercostal muscle action inferred from finite‐element analysis. J Appl Physiol 70: 2712‐2712, 1991.
 122. Margulies SS, Farkas GA, Rodarte JR. Effects of body position and lung volume on in situ operating length of canine diaphragm. J Appl Physiol 69: 1702‐1702, 1990.
 123. Margulies SS, Rodarte JR, Hoffman EA. Geometry and kinematics of dog ribs. J Appl Physiol 67: 707‐707, 1989.
 124. Marshall R. Relationships between stimulus and work of breathing at different lung volumes. J Appl Physiol 17: 917‐917, 1962.
 125. McCool FD, Loring SH, Mead J. Rib cage distortion during voluntary and involuntary breathing acts. J Appl Physiol 58: 1703‐1703, 1985.
 126. McCully DK, Faulkner JA. Length‐tension relationship of mammalian diaphragm muscles. J Appl Physiol 54: 1681‐1681, 1983.
 127. McKenzie DK, Gorman RB, Tolman J, Pride NB, Gandevia SC. Estimation of diaphragm length in patients with severe chronic obstructive pulmonary disease. Respir Physiol 123: 225‐225, 2000.
 128. Mead J. Mechanics of the chest wall. In: Pengelly LD, Rebuck AS, Campbell EJM, editors. Loaded Breathing. Edinburgh: Churchill Livingstone, 1974, pp. 35‐49.
 129. Mead J. Functional significance of the area of apposition of diaphragm to rib cage. Am Rev Respir Dis 119: 31‐31, 1979.
 130. Mead J, Loring SH. Analysis of volume displacement and length changes of the diaphragm during breathing. J Appl Physiol 53: 750‐750, 1982.
 131. Mead J, Yoshino K, Kikuchi Y, Barnas M, Loring SH. Abdominal pressure transmission in humans during slow breathing maneuvers. J Appl Physiol 68: 1850‐1850, 1990.
 132. Minh VD, Dolan GF, Konopka RF, Moser KM. Effect of hyperinflation on inspiratory function of the diaphragm. J Appl Physiol 40: 67‐67, 1976.
 133. Mortola JP, Sant'Ambrogio G. Motion of the rib cage and the abdomen in tetraplegic patients. Clin Sci Mol Med 54: 25‐25, 1978.
 134. Newman S, Road J, Bellemare F, Clozel JP, Lavigne CM, Grassino A. Respiratory muscle length measured by sonomicrometry. J Appl Physiol 56: 753‐753, 1984.
 135. Newsom Davis J, Goldman M, Loh L, Casson M. Diaphragm function and alveolar hypoventilation. Q J Med 65: 87‐87, 1976.
 136. Ninane V, Gorini M. Adverse effect of hyperinflation on parasternal intercostals. J Appl Physiol 77: 2201‐2201, 1994.
 137. Pengelly LD, Alderson AM, Milic‐Emili J. Mechanics of the diaphragm. J Appl Physiol 30: 797‐797, 1971.
 138. Petroll WM, Knight H, Rochester DF. Effect of lower rib cage expansion and diaphragm shortening on the zone of apposition. J Appl Physiol 68: 484‐484, 1990.
 139. Pettiaux N, Cassart M, Paiva M, Estenne M. Three‐dimensional reconstruction of human diaphragm with the use of spiral computed tomography. J Appl Physiol 82: 998‐998, 1997.
 140. Raper AJ, Thompson WT Jr, Shapiro W, Patterson JL Jr. Scalene and sternomastoid muscle function. J Appl Physiol 21: 497‐497, 1966.
 141. Ringel ER, Loring SH, Mead J, Ingram RH Jr. Chest wall distortion during resistive inspiratory loading. J Appl Physiol 60: 63‐63, 1986.
 142. Road J, Newman S, Derenne JP, Grassino A. In vivo length‐force relationship of canine diaphragm. J Appl Physiol 60: 63‐63, 1986.
 143. Robertson CH Jr, Foster GH, Johnson RL Jr. The relationship of respiratory failure to the oxygen consumption of, lactate production by, and distribution of blood flow among respiratory muscles during increasing inspiratory resistance. J Clin Invest 59: 31‐31, 1977.
 144. Robertson CH Jr, Pagel MA, Johnson RL Jr. The distribution of blood flow, oxygen consumption, and work output among the respiratory muscles during unobstructed hyperventilation. J Clin Invest 59: 43‐43, 1977.
 145. Rosenblueth A, Alanis J, Pilar G. The accessory motor innervation of the diaphragm. Arch Int Physiol Biochim 69: 19‐19, 1961.
 146. Sant'Ambrogio G, Saibene F. Contractile properties of the diaphragm in some mammals. Respir Physiol 10: 349‐349, 1970.
 147. Saumarez RC. An analysis of action of intercostal muscles in human upper rib cage. J Appl Physiol 60: 690‐690, 1986.
 148. Sears TA. Efferent discharges in alpha and fusimotor fibres of intercostal nerves of the cat. J Physiol 174: 295‐295, 1964.
 149. Sharp JT, Goldberg NB, Druz WS, Danon J. Relative contributions of rib cage and abdomen to breathing in normal subjects. J Appl Physiol 39: 608‐608, 1975.
 150. Smith J, Bellemare F. Effect of lung volume on in vivo contraction characteristics of human diaphragm. J Appl Physiol 62: 1893‐1893, 1987.
 151. Sprung J, Deschamps C, Hubmayr RD, Walters BJ, Rodarte JR. In vivo regional diaphragm function in dogs. J Appl Physiol 67: 655‐655, 1989.
 152. Sprung J, Deschamps C, Margulies SS, Hubmayr RD, Rodarte JR. Effect of body position on regional diaphragm function in dogs. J Appl Physiol 69: 2296‐2296, 1990.
 153. Strauss LH. Z Ges Exptl Med 86: 244, 1933, cited by Leigh Collins J, Satchwell LM, Abrams LD. Nerve supply to the crura of the diaphragm. Thorax 9: 22‐25, 1954.
 154. Strohl KP, Mead J, Banzett RB, Lehr J, Loring SH, O'Cain CF. Effect of posture on upper and lower rib cage motion and tidal volume during diaphragm pacing. Am Rev Respir Dis 130: 320‐320, 1984.
 155. Strohl KP, Mead J, Banzett RB, Loring SH, Kosch P. Regional differences in abdominal muscle activity during various maneuvers in humans. J Appl Physiol 51: 1471‐1471, 1981.
 156. Taylor A. The contribution of the intercostal muscles to the effort of respiration in man. J Physiol 151: 390‐390, 1960.
 157. Urmey WF, De Troyer A, Kelly SB, Loring SH. Pleural pressure increases during inspiration in the zone of apposition of diaphragm to rib cage. J Appl Physiol 65: 2207‐2207, 1988.
 158. Wilson TA, Boriek AM, Rodarte JR. Mechanical advantage of the canine diaphragm. J Appl Physiol 85: 2284‐2284, 1998.
 159. Wilson TA, De Troyer A. Effect of respiratory muscle tension on lung volume. J Appl Physiol 73: 2283‐2283, 1992.
 160. Wilson TA, De Troyer A. Respiratory effect of the intercostal muscles in the dog. J Appl Physiol 75: 2636‐2636, 1993.
 161. Wilson TA, De Troyer A. The two mechanisms of intercostal muscle action on the lung. J Appl Physiol 96: 483‐483, 2004.
 162. Wilson TA, De Troyer A. Diagrammatic analysis of the respiratory action of the diaphragm. J Appl Physiol 108: 251‐251, 2010.
 163. Wilson TA, Legrand A, Gevenois PA, De Troyer A. Respiratory effects of the external and internal intercostal muscles in humans. J Physiol 530: 319‐319, 2001.

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André De Troyer, Aladin M. Boriek. Mechanics of the Respiratory Muscles. Compr Physiol 2011, 1: 1273-1300. doi: 10.1002/cphy.c100009