154 CLINICAL APPLIED ANATOMY 



a proceeding should not be carried out without an accompanying 

 tarsectomy. 



A cuneiform tarsectomy for varus has the base of the wedge 

 looking outwards and somewhat upwards. The section as a rule 

 passes through the anterior part of the os calcis and the head of 

 the astragalus posteriorly; through the joint between the cuboid 

 and the fourth and fifth metatarsals, across the base of the 

 external cuneiform and through the navicular anteriorly. There- 

 fore the parts removed will consist of portions of the anterior 

 part of the os calcis and the astragalus, the whole of the cuboid 

 and parts of the external cuneiform and the navicular. In the 

 young subject it must be remembered that all this mass is to 

 a very great extent cartilaginous. 



Acquired Talipes Equino-varus. Infantile paralysis is the 

 most common cause of acquired varus or equino-varus. In this 

 condition the deformity is brought about by the active contraction 

 of the unopposed non-paralysed muscles and the subsequent 

 shortening of the muscular tissue between the approximated 

 points of their origin and insertion. Hence it comes about that 

 a deformity will result with rigidity of the neighbouring joints. 

 In order that equino-varus should occur, paralysis of the anterior 

 tibial group is necessary that is to say, paralysis of the tibialis 

 anticus, extensor proprius hallucis, extensor longus digitorum 

 and peroneus tertius, supplied by the anterior tibial nerve. In 

 some cases, moreover, the peroneus longus and brevis may be 

 likewise affected. Seeing that anterior tibial paralysis is the most 

 common form met with as a result of anterior poliomyelitis, it 

 follows that equino-varus is the usual variety of deformity that 

 ensues. 



In cases, however, where paralysis involves both the anterior and 

 posterior tibial groups, it is extremely unlikely that contraction 

 and rigidity will occur, but laxity and flail-like joints will result. 



In those cases in which one group of muscles alone is paralysed, 

 an interesting anatomical question arises in connection with 

 the method of treatment by tendon-grafting or tendon -trans- 

 plantation. In cases of equino-varus resulting from paralysis 



