RESPIRATION IN MAN 197 



the thoracic type, and with the extent of the respiratory move- 

 ment. Braune estimated ita movement at 5 to 13, Rothschild, 

 who regards limitation in the movement of this joint as a cause 

 of consumption, estimated the average movement (in full inspira- 

 tion) to be 15 - 85 in the male and 12'85 in the female ; while the 

 writer, who was unaware of Rothschild's observations, found it 

 varied from 1 to 16. The degree of movement depends chiefly 

 on the inspiratory behaviour of the body of the sternum, which 

 is extremely variable. In some individuals the lower end of the 

 sternum during the elevation of the thorax during inspiration may 

 be drawn towards the spine or move forward to a less degree than 

 the upper end of the body of the sternum ; in such, the sterno- 

 manubrial movement is free. If, on the other hand, the lower 

 end of the sternum moves more freely away from the spine than 

 the upper end, the movement at the joint is less extensive. At 

 the sterno-manubrial joint, the operculum or lid of the thorax 

 articulates with the anterior thoracic wall. The prominence of this 

 joint on the surface of the thorax is extremely variable so many 

 conditions may render it unduly prominent. Ludwig, the Parisian 

 physician, is said to have regarded an undue prominence of the 

 articulation (Angulus Ludovici) as an indication of phthisis ; but 

 researches made by recent German writers have failed to trace 

 such a statement in Ludwig's writings. Rothschild found that 

 the sterno-manubrial movements were limited or absent in 

 phthisical subjects, and ascribed the susceptibility of the apex to 

 phthisis as due to an anchylosis or limitation of movement at this 

 joint. In his opinion a free manubrio-sternal movement is neces- 

 sary if the apex of the lung is to be properly expanded. Freund 

 attributes the incomplete expansion of the apex in the phthisical 

 action to a congenital shortening and ossification of the cartilage 

 of the first rib. It is true that the necks of the first pair of ribs 

 are so articulated to the spine that with the elevation of the 

 manubrium sterni there is some degree of torsion of their cartilages, 

 but the amount of the torsion is slight in extent because of the 

 particularly loose manner in which the heads of those ribs are 

 bound to the first dorsal vertebra. The writer, unaware of the 

 observations and theories of Freund and Rothschild, had concluded 

 that the ossification of the first costal cartilage and limitation of 

 the sterno-manubrial movements were consequences rather than 

 causes of a limited expansion of the apices of the lungs. In 



