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 Part III. 23 6 A N A T O M Y. with the tibialis pofterior and peronaea pofterior, it runs downward, and gives rami to all the mufcles that terally fo that thefe two bones are in a manner furrounded by lie on the backfide of that bone, one of which enters arteries. the bone itfelf on one fide of the linea afpera. Having fent off all thefe three branches, the arteria At the joint of the foot, it fends out branches which cruralis runs down between the fartorius, valtus inter- run between the aftragalus and os calcis, being diftributed the articulation and to the bones of the tarfus. aus, and triceps, giving branches to all the parts near to Having the fold of the foot, it fends off, toit. It is covered by the fartorius all the way to the ward both paffed fides, other rami, which communicate with lower part of the thigh, where it is infleffed backward pofterior tibialis and peronaea; all thefe branches over the triceps tertius a little above the internal condyle the of the os femoris. Afterwards, continuing its courfe making a kind of circles round the tarfus. through the hollow of the ham, it is called arteria po- Afterwards the anterior tibial artery advances on the convex fide of the foot, as far as the interftice between plitea. The poplitea, while in the ham, is covered only by the firft and fecond metatarfal bones; between the heads of which it fends a large branch, which perforates the the integument, fending off branches toward each fide, fuperior interoffeous mufcles, and, joining the tibialis which run up upon the condyles, and communicate with pofterior, forms an arch on the fide of the foot. the lower ramifications of the arteria cruralis. It fends rami to the joint of the kndfe, one of which It likewife fends two or three confiderable branches the other metatarfal bones, which go to the reft of at lead pafles between the crucial ligaments. As it runs over the interoffeous mufcles, integuments, <bc. and commudown, it fends branches to the gaftrocnemii and popli- nicate with each other. teus; and having reached the backfide of the head of Laftly, artery terminates by two principal the tibia, it gives off two branches, one to each fide. branches, oneThisof which to the thenar and infide of The firrt or internal branch furrounds the fore-part the great toe; the other goes upon the outfide of the of the head of the tibia, palling betvyeen the bone and in- great toe, and the infide isof fpent the fecond toe. ternal lateral ligament; an^ befides feveral other ramifi- The tibialis pofterior, called likewife furalis, runs cations, fends up a fmall branch, which communicates between the folei, tibialis pofticus, flexor digitowith the arteries that lie round the condyles of the os fe- down rum ^communis, and flexor pollicis; giving branches to moris. to the tibia, and to the marrow of that The fecond or external branch runs over the head of thefe mufcles, through a particular canal in its pofterior and upthe fibula, and between the head of the tibia and exter- bone, part. nal lateral ligament of the knee, furrounding the articu- perAfterwards runs behind the inner ankle, communilation all the way to the ligament of the patella, and cating with theittibialis anterior, and furrounded by the communicating with the branches which lie round th§ condyles of the os femoris, together with a branch of neighbouring veins; and paffes to the foie of the foot between the concave fide of the os calcis and thenar mitfthe firff. or internal ramus. Immediately after the origin of thefe two rami, and cle, where it divides into two branches, one large or exthe other fmall or internal. before the poplitea ends, it fends a fmall artery down on ternal, great branch, or arteria plantaris externa, paffes the backfide of the interoffeous ligament, very near the on The concave fide of the os calcis obliquely under the tibia, into which it enters by a particular hole a little a- foietheof the foot, to the bafis of the fifth metatarfal bone, bove the middle portion of the bone. thence runs in a kind of arch toward the great As the poplitea ends, it divides into two principal and from communicating there with the tibialis anterior, which ’ branches, one of which runs between the heads of the toe, the interoffeous.mufcles. . tibia and fibula, palling from behind forwards on 4he in- perforates convex fide of this arch fupplies both fides of the teroffeous ligament, where it takes the name of arteria laftThe three toes, and the outfide of the fecond toe, formtibialis anterior. -The fecond branch divides into two ing fmall communicating arches as in the hand. others; one internal and largeft, called arteria peronaa The firjall or arteria plantaris interna, having anterior; the other pofterior and fmalleft, named arteria reached beyondbranch, the middle of the foie of the foot, is diperonaa pojlerior. into two; one of which goes to the great toe, The tibialis anterior, having paffed between the heads vided with the ramus of the tibialis anterior ; of the tibia and fibula, fends fmall branches upward and communicating other is diftributed to the firft phalanges of the other laterally. The fuperior branches communicate with thofe the communicating with the ramifications from the arch rami of the popliteus which lie round the articulation; and toes, mentioned. the lateral branches go to the neighbouring parts. Af- already arteria peronasa runs down on the backfide of the terwards this tibial artery runs down on the forefide of The between the foleus and flexor poliicis, to which, the interoffeous ligament, toward the outfide of the ti- fibula, and to the neighbouring parts, it gives rami in its pafbia, between the mufculus tibialis anticus and extenfor fage. pollicis. to the_ lower third part of the fibula, Having run laterally on the tibia for about two thirds Havingoffreached a confiderable branch, which runs in between of the length of that bone, it paffes on the forefide un- itthefends and that bone, pafling between their extremities der the common annular ligament, and extenfor pollicis, fromtibia behind forward, below the interofleous ligament, to the articulation of the foot; giving off feveral rami both to the right and left hand, which communicate la- and is diftributed to the integuments of the tarfus.Laftly,