THE REGION OF THE ANKLE AND FOOT 497 



In each case, after the incision has been made, a blunt-pointed 

 tenotome is introduced between the tendon and the bone on 

 which it lies. The tendon is then stretched across the edge of 

 the knife and divided. 



The plantar aponeurosis may be divided through a number 

 of small incisions, made in the neighbourhood of the tightened 

 bands. 



Ossification of the Metatarsal Bones and Phalanges. 

 Each of the metatarsals and each of the phalanges possesses a 

 single epiphysis. In the cases of the second, third, fourth, and 

 fifth metatarsals, the epiphysis forms the rounded head of the 

 bone. It appears during the third or fourth years and unites 

 with the diaphysis at eighteen. In the case of the first 

 metatarsal, the epiphysis forms the base of the bone. It 

 appears during the second or third years and joins the diaphysis 

 at eighteen. 



The ossification of the phalanges is similar to that of the first 

 metatarsal. The epiphyses, which appear at the fourth year 

 and fuse at eighteen, form the proximal extremities. 



It may be noted that the first metatarsal resembles the 

 phalanges still further in the frequency with which it is attacked 

 by tuberculous disease. 



Tuberculous disease of the metatarsals commences near the 

 centre of the diaphysis as an osteo-myelitis, probably owing to 

 the fact that the nutrient artery, on entering the bone, at once 

 divides into a leash of small vessels and not into large ascending 

 and descending branches, as it does in the long bones proper. 



The first metatarsal may be resected subperiosteally through 

 a dorso-medial incision, which at once exposes the bone. After 

 the periosteum has been freely elevated, the diaphysis is divided 

 near the head and can be wrenched away from the epiphyseal 

 cartilage, which is left behind with the basal epiphysis. In this 

 way the surgeon avoids opening into the tarso-metatarsal and 

 the metatarso-phalangeal joints. 



The same method may be followed in resection of any of the 

 other metatarsals, save that the diaphysis must be divided near 

 the base and then wrenched away from the distal epiphysis 



(P- 93)- 



In sub-periosteal resection of the proximal phalanges of the 



lateral four toes, a dorso-lateral incision is employed to avoid 

 injuring the tendons of the lumbricals, which are inserted into 

 the tibial sides of the phalangeal bases. 



32 



