172 MR. TOYNBEE ON THE ORGANIZATION AND NUTRITION 



of supplying" the articular cartilage with a nutrient fluid, and that they do so without 

 entering into its substance. It is necessary that the nutrient fluid brought to the 

 inner surface of this lamella should penetrate its substance. It is most probable 

 that it traverses only the thin layer of the lamella, and not the vertical portions. 

 This thin layer has already been stated to be almost entirely composed of osseous 

 corpuscles, which without doubt assist to convey the fluid from the cancelli into the 

 cartilage. 



It appears to me, that not only those vessels which are in immediate contiguity 

 with the articular lamella have the function of nourishing the articular cartilage, but 

 that the large and very numerous vessels which ramify through the substance of the 

 cancellous extremities of bones, and which enter them by large orifices at their non- 

 articular circumference, eliminate into the cancelli a nutrient fluid, which passes 

 through the articular lamella and nourishes the cartilage. 



That the nutrition of articular cartilage is actually efl^ected by vessels in the can- 

 celli, may be inferred from their dilatations and convolutions in its vicinity, and from 

 the absence of any other means, as shown by my injections. 



In addition to my own preparations, I may refer, in corroboration of the view of 

 the non-vascularity of articular cartilage, to a preparation presented to the Museum 

 of the Royal College of Surgeons by Mr. Swan. 



It consists of the bones of the posterior part of the cranium of a Sheep, which, sub- 

 sequently to death, was allowed to remain suspended with its head downwards, so 

 as to cause the blood to gravitate into it. The vessels forming convolutions in the 

 canals of Havers are much distended with blood of a dark colour. The articular 

 cartilage covering the condyloid processes is, however, perfectly white ; not a par- 

 ticle of blood can be discovered in it. 



The researches which I have made upon those morbid states of articular cartilage, 

 in which blood-vessels are prolonged into its substance, and upon the manner in 

 which the vessels are introduced into it, confirm the opinions here advanced. I 

 shall defer entering upon them to another opportunity*. 



Having proved, I think, that in the healthy state no blood-vessels pass from the 

 interior of bone into the substance of the articular cartilage at its attached surface, 

 I shall now proceed to show that no vessels enter it at its free or synovial surface. 



Of the Vessels of the Synovial Membrane which caver the Articular Cartilage, and 

 of the Nutrition hy them of the latter. — In a former part of this paper, the vessels 

 appertaining to the free or synovial surface of articular cartilage in the young sub- 

 ject have been described. A few additional observations upon them in the adult 

 state are required here. 



During foetal and infantile life, previous to the period when the articular cartilages 

 are subject to pressure, the synovial vessels extend over certain portions of them, from 



* The investigations of Sir B. Brodie, Mr. Mayo, and more recently of Mr. Liston, leave no doubt that 

 in some diseases to which articular cartilage is subject, blood-vessels are distributed throughout its substance. 



