346 



BONES OF THE FOOT. 



highest bone of the tarsus; from this bone, 

 again, the weight is transmitted to the os 

 calcis in the backward direction, and to the 

 anterior row of tarsal bones in front, where 

 the transverse extent of the tarsus is consider- 

 ably increased, in order to enlarge the basis of 

 support. It is worthy of remark that the 

 solidity of the anterior part of the tarsus is less 

 on its inner than on its outer side, the effect of 

 which is to increase the elasticity of the former 

 part without materially diminishing its strength. 

 The object of this arrangement appears to be ex- 

 plained by the observation that the weight of the 

 body is transmitted by the astragalus principally 

 to the inner side of the tarsus. It is toward the 

 inner side also that the concavity of the under 

 surface of the tarsus is most evident, by which 

 not only can the sole of the foot adapt itself 

 to the irregularities of surface to which it is 

 applied, but it is enabled to yield under the 

 superincumbent weight, and so to counteract 

 the effects of sudden concussion in walking, 

 leaping, &c. 



In the foot anatomists have described two 

 arches as connected with its mechanical arrange- 

 ments. The first is best seen in a profile view 

 of the foot ; it is termed the antero-posterior 

 arch ; upon this arch we rest when the toes are 

 applied to the ground, the posterior extremity 

 of it being the heel, the anterior the balls of the 

 toes, and the astragalus resembling the key- 

 stone of the arch. The second is the transverse 

 arch, which may be most satisfactorily demon- 

 strated by a transverse section made along the 

 line of the cuneiform bones. The effect of the 

 constant and violent exercises of the foot to 

 which public dancers are accustomed is to in- 

 crease the mobility of the different parts of the 

 foot, to an extent which unfits it, in a great 

 measure, for its office as an instrument of sup- 

 port in standing or walking, as may be ob- 

 served, says Sir C. Bell, in any of the retired 

 dancers and old figurantes. By standing so 

 much on the toes, he adds, the human foot is 

 converted to something more resembling that 

 of a quadruped, where the heel never reaches 

 the ground, and where the paw is nothing more 

 than the phalanges of the toes. 



The following considerations connected with 

 the human foot may be quoted as so many in- 

 dications that the erect attitude is natural to 

 man: 1. the articulation of the foot at right 

 angles with the leg; 2. the great comparative 

 size of the foot, contrasted with that of other 

 animals; 3. the great transverse extent of the 

 foot ; 4. the predominance of its solid parts, 

 the tarsus and metatarsus, over its moveable 

 part, the phalanges ; 5. the direction of the me- 

 tatarsal bone supporting the great toe ; its situa- 

 tion and want of mobility ; 6. the limited mo- 

 bility of the phalanges of the foot as compared 

 with those of the fingers ; 7. the horizontal po- 

 sition of the os calcis ;* the excess of its trans- 



* " Even the Simiae and the bear," says Mr. 

 Lawrence, " have the end of the os calcis raised, 

 so that this bone begins to form an acute angle with 

 the leg; the dog, the cat, and other digitated 

 quadrupeds, even the elephant himself, do not rest 

 on the tarsus or carpus, but merely on the toes ; 



verse extent at its posterior over that of its an- 

 terior part, and the developement of its tuber- 

 cles ; 8. the great strength and developement 

 of the calcaneo-cuboid ligament; 9. the early 

 ossification of the bones of the foot as compared 

 with those of the hand. 



The extraordinary extent to which art can 

 modify the positions of the several bones, and 

 the form of the whole foot, is remarkably ex- 

 emplified in the case of the Chinese foot. It 

 is well known that, among other barbarities 

 practised on Chinese females, their feet are 

 from an early period subjected to the most 

 violent pressure, with the view of reducing them 

 to that diminutive size which is esteemed a 

 point of great beauty. Hence the anatomical 

 examination of a foot thus compressed is a 

 point of great interest, not alone to the physio- 

 logist, but also to the surgeon, as indicating 

 what properly applied force may do when em- 

 ployed at a sufficiently early period. An inte- 

 resting account of such an examination was 

 communicated in the year 1829 to the Royal 

 Society by Mr. Bransby Cooper, from whose 

 paper we extract the following statements. 



The foot at first view had the appearance of 

 being congenitally deformed ; it was remarka- 

 bly short; from the heel to the great toe its 

 measurement did not exceed five inches ; it was 

 very much contracted in its transverse dimen- 

 sions, and the instep extremely high, being un- 

 usually convex not only from before backwards, 

 but also from side to side. 



" The position of the os calcis," to use Mr. 

 B. Cooper's words, " is very remarkably altered: 

 instead of the posterior projection which usually 

 forms the heel, a straight line is preserved in 

 this direction, not deviating from the line of the 

 tibia; and the projecting point which forms in 

 an ordinary foot the most posterior process into 

 which the tendo Achillis is inserted, touches 

 the ground, and becomes the point d'appui for 

 sustaining the whole weight of the body. The 

 articular surface of the os calcis in connexion 

 with the cuboid bone is about half an inch an- 

 terior to and two inches above this point ; 

 while the astragalar joint is behind and some- 

 what below the calco-cuboidal articulation ; 

 consequently the direction of the os calcis, (in 

 its long axis,) instead of being from behind for- 

 wards, is from below upwards, with the slightest 

 possible inclination forwards. The most pro- 

 minent parts of the instep are the round head 

 of the astragalus and the cuboidal articulation 

 of the os calcis. From this the remaining 

 tarsal bones slope downwards at nearly a right- 

 angular inclination to join the metatarsal bones, 

 whose obliquity is still downwards, until they 

 rest on their phalangeal extremities." 



The points of support are the os calcis, the 

 anterior extremity of the metatarsal bone of the 

 great toe, and the dorsal surface of the fourth 

 and fifth toes, which are bent under the foot so 

 as to press the ground at this part. 



(R. B. Todd.) 



the cloven-hoofed ruminants and the Solipeda touch 

 the ground merely with the extremities of the third 

 phalanges, and the os calcis is raised nearly into a 

 perpendicular position." 



