T. Lewis and D. Embleton 
39 
There are thus connecting links between the two main types (cp. hand of V, 7). 
The type in wliich there is preaxial affection as opposed to splitting is a little 
commoner. lu neither type is the radius or ulna ever affected, and it can only 
be in exceptional cases, if in any, that the carpus suffei's. Both types may be 
associated with syndactyly or Polydactyly. 
Syndactyly is generally confined to the 4th and 5th digits (Fig. 14), but when 
more are present and complete it may unite these ; the rule is for two adjacent 
fingers to be united by skin when they have phalanges. The union may be by 
the deeper structures as well, and in a fair number of cases is bony *"-'^*'"- The 
subject will be reverted to under the discussion of the cross-bones. 
Polydactyly occurs less frequently. The supernumerary digits may be rudi- 
mentary'', the extra digit may be articulated to the end of a phalanx (V, 38), to 
the end of a metacarpal (V, 6, 7), or to the carpus'*". It may be fixed to the side 
of the thumb metacarpal (V, 6). When articulating with the end of a meta- 
carpal or carpus the digit is fully developed and has three phalanges, even when 
the joint is between it and the 1st metacarpal. Thus the varieties of Polydactyly 
which occur are similar to those found when vmassociated with other lesions 
(cp. Annandale). It occurs most commonly in those split foot cases where there 
is no other affection of the hands but is not confined to these (V, 6). There 
is only in isolated cases more than one extra digit on each handf. 
Thus it is seen that the hands show even more variation than the feet ; never- 
theless they show points common to the majority. Notably the mobility, the 
fleshy pads over the abnormal bony prominences, contractures and syndactyly 
of remaining fingers, and the exemption of the carpus. When the two main types 
are taken separately the bony deformities in different individuals show very close 
resemblances, as detailed above ; moreover there are connecting links between 
these main types. 
It has now been shown how much both hands and feet vary, but that in spite of 
this there are points of strong resemblance between the affected limbs of different 
individuals. Moreover there is a variation, usually limited, on the two sides of the 
body and the variations of hand or foot appearing in different families are strikingly 
similar. Thus in the larger families"*''" though there may be a predominant 
type, yet it is the rule for each family to provide examples of many types, and in one 
family almost all types are represented^^ Again it has not been found possible to 
connect the occurrence of any particular type of foot with any particular type of 
hand. It was at first thought that the type of foot in which the split occurs at the 
2nd digit might be more often found in association with that type of hand in 
which the preaxial side is mainly defective, and that sjjlitting of the feet and hands 
at the central digit might be found to occur more commonly in conjunction with 
each other. But when allowance is made for the tendency shown here and there 
* In these the union is closest at the distal end, and the nails are united in a central furrow. 
t For exceptions see 
X signifies the family now reported. 
