410 
AN ESSAY ON CHRONIC PODOTROCHOLITIS. 
quently contracts adhesions with the navicular, but not throughout 
the whole extent of the points in contact, but at those parts where 
the bursal membrane is destroyed, or at the portions of tendon de- 
nuded by the disunion and rupture of the superficial fibres. These 
latter only become partially detached at first ; but gradually this 
pathological action progresses, until at last the whole of the ante- 
rior surface of the tendon becomes covered with elevations and 
depressions, and thoroughly uneven. Arrived at this degree of 
disorganization, it very often presents red striae, similar in appear- 
ance to muscular fibres ; these striae appear to be produced by ex- 
udation : at other places greenish spots may be perceived. The 
destruction of the tendon progresses with the duration of the lesion ; 
it takes place from before backwards, and in spots, until at last the 
tendon becomes so thin as to be transparent : sometimes nothing 
remains of it but some thin and softened bundles of fibres at a dis- 
tance from each other. The rupture of these is the natural conse- 
quence of this destructive process ; but before that takes place the 
tendon has attached itself to a fresh place, to the superior and pos- 
terior edge of the navicular bone ; a solid fibrous layer serves to 
unite these two parts, which is furnished by the right superior sus- 
pensory ligament of the navicular, that ligament being for the pur- 
pose very much thickened and abnormally developed. 
When the disease has been going on for some considerable time 
the fluid contained in the bursa almost entirely disappears, or, if it 
remains, it is transformed into a thick, yellowish, white flaky liquid, 
and frequently holds the tendinous fibres in solution, which can 
easily be distinguished. 
The consequences of inflammation of the navicular are, in all 
cases, a diminution in the size of the bone, sometimes accom- 
panied, towards the latter stages, with abnormal productions which 
attack other parts. Caries is the primary cause of decrease in the 
size of the bone. This caries is either deep or superficial, invading 
one or more points, as the crest, or the lateral depressions of the 
navicular. Before the caries makes its appearance, little eleva- 
tions of about the size of a grain of millet seed appear upon the 
posterior surface : when the bone has been macerated they present 
themselves under the form of little exostoses. I cannot decide 
whether or not these elevations should be classed under the head 
of the tubercles designated by Nelaton* enkistts : they attracted 
my attention too late, and I did not submit them to a microscopic 
examination. One thing I can speak positively with regard to is, 
that these exostoses, which have also been observed by Turner, 
are the precursors of the caries which attacks the elevated parts. 
* Recherches sur I’affection tuberculeuse des os. 1837. 
