160 
On tlie Sesamoids of the Ktiee-Joint 
progressed. The fahellae enumerated include both hemisesamoids and ortho- 
sesamoids. The results are in rough agreement with Ost's short series, but shew a 
far higher frequency than Pfitzner's record. 
We now turn to the interesting Seventh Report of the Guminittee of Collective 
Investigation of the Anatomical Society of Great Britain and Ireland for the year 
1896 — 1897*. We have already commented on the high percentage of lateral 
fahellae reached by Gruber, but these percentages are at least doubled in the 
statistics of this Report. Over 40 of occurrence oi fahellae are here recorded, and 
if this rate of increase of percentage continues we shall soon have to return to the 
standpoint of Vesalius ! One wonders (i) if the distinction between limb and 
cadaver has always been maintained, (ii) if the distinction between condyle and 
limb has also been maintained"]', and lastly supposing the results do indicate the 
number of fahellae per 100 condyles, (iii) if the " Knotenpunkt " itself in which the 
lateral fabella is to be sought has not been occasionally mistaken for a sesamoid |. 
In 287 limbs of both sexes examined, 81 lateral fahellae and 39 mesial fahellae 
were found. These figures provide 28"2'/^ of lateral fahellae and VS'6°/^ of 
mesial fahellae, i.e. about twice as many lateral as mesiak Now Pfitzner, Gruber 
and ourselves have not discovered in man any mesial fahellae. Hence we must put 
against Pfitzner's 10"34°/^ and Gruber's 17'1°/^ the 41-8°/^ of the present investi- 
gation. But the matter takes a different form if we distinguish between osseous 
and non-osseous fahellae^. Of the 81 lateral fahellae only 28 were orthosesamoids ; 
and of the 39 mesial fahellae only three were reported as osseous. In other words 
only 9"75°/^ of orthosesamoidal lateral fahellae occur, and 1"05°/^, of orthosesamoidal 
mesial fahellae. These results are very luminous for the controversies of the 
mediaeval anatomists. Supposing those three mesial orthosesamoids were actually 
and correctly diagnosed then if the mediaeval anatomists had, as they probably had 
an osseous body in view they might easily have examined a hundred or more limbs 
without finding a mes'vAl fahella. It is even conceivable that Pfitzner might not 
find one in 290 limbs. It is less conceivable that they should have escaped Gruber 
in the case of 2340 limbs, and in the case of both Pfitzner and Gruber who were 
well acquainted with hemisesamoids, it is surprising that neither found a mesial 
hemisesamoid in 2630 limbs examined, when they ought to have found 331 
on the scale of the Collective Investigation Report. It must be quite clear that 
these different investigators had a totally different conception of the nature 
of a non-osseoiis sesamoid, and that this is the origin of the surprising percentage 
differences we encounter in these investigations as to the presence of fahellae 
* Journal of Anatomy and Plnjsiology, Vol. xxxii, p. 182, London, 1898. 
t A condyle gives only one chance, a limb two chances, and a cadaver four chances of a, fahella. 
X The Report says: "With regard to the constitution of the bodies we have evidence that in many 
of the investigations no microscopical examination was made. We shall therefore content ourselves 
with dividing the cases in which sesamoid bodies occur into two classes, — first those in which the bodies 
were osseous; secondly those in which they were of some other materials (fibrous, fibro-cartilaginous, 
or cartilaginous)," p. 184. 
§ It is not, perhaps, adequate to treat these as orthosesamoids and hemisesamoids, as they may 
contain fibrous structures, which Gruber and probably we ourselves should not class as hemisesamoids. 
