574 



APPLIED ANATOMY. 



AMPUTATIONS OF THE FOOT. 



The foot may be amputated through the midtarsal or tarsometatarsal joints. 

 Ordinarily they give unsatisfactory stumps owing to the heel being pulled up by the 

 tendo calcaneus (Achillis), and the shape of the inner part of the tarsal arch. This 

 causes the patient to walk on the end of the stump, which soon becomes painful. 



To perform these operations skilfully it is essential that one be familiar with the 

 lines of the joints. Plantar flaps are used because the skin of the sole is tougher 

 than that of the dorsum and the cicatrix is out of the line of pressure. 



Midtarsal (Chopart's) Amputation. This is made through the midtarsal 

 joint. The guides to the joint are the tubercle of the scaphoid (navicular) on the 



FIG. 592. Chopart's midtarsal amputation 

 of the foot. 



Plantar 

 flap 



FIG. 593. Lisfranc's tarsometatarsal amputation 

 of the foot. 



inside and the ridge on the anterior end of the os calcis, midway between the external 

 malleolus and the fifth metatarsal bone, on the outer side. A short dorsal and a long 

 plantar flap are cut. The plantar flap is longer on its inner side to allow for the 

 greater thickness of the foot on that side. It is easier to begin the disarticulation 

 on the inside, going in just behind the tubercle of the scaphoid (navicular). This 

 part of the joint is convex forward. On reaching the outer edge of the astragalus 

 (talus) care should be taken not to slip posteriorly between the astragalus and os 

 calcis, but to continue laterally. The extensor tendons are to be sutured to the end 

 of the stump and frequently the tendo calcaneus (Achillis) is cut in an attempt to 

 prevent subsequent elevation of the heel. (Fig. 592). 



Carelessness may result in opening the joint in front instead of behind the 

 scaphoid (navicular). 



