VARIETIES OF THE BEACHIAL ARTERY. 



403 



arch, from which the pronator teres in those cases arises, and which descends to 

 the inner condyle from the occasional prominence called the supra-condylar 



Fig. 264. — DissF.cTioN OF THE Right Arm, show- 

 ing AN EXAMPLE OP HIGH SEPAKATION OF THE 



Radial Artery from the Brachial, and an 



ENLARGED MEDIAN ArTERY IN THE FoRE- 



ARM (from Tiedemann). ^ 



Fig. 26^ 



1, on the tendon of tlie latissimus dorsi, points 

 to the upper part of the brachial artery ; 2, tho 

 brachial artery after giving off the radial ; 3, the 

 radial rising in the upper third of the arm and 

 descending in its usual situation in the fore-arm ; 

 3', its superficial volar branch ; 4, the ulnar 

 artery in its usual course, forming at 5, the 

 superficial palmar arch, from which three of the 

 palmar digital arteries and the princeps pollicis 

 take origin ; the radial supplying the branches 

 to the index finger and one side of the middle 

 finger ; 6, the superior profunda branch of the 

 brachial artery ; 7, muscular branches ; 8, anas- 

 tomotic ; 9, recurrent radial ; 10, anterior inter- 

 osseous giving an unusually large median branch 

 which descends over the wrist to unite with the 

 superficial palmar arch. 



^ 



process. Somt^times this disposition occnra 

 without the development of any bony promi- 

 nence. 



As an extremely rare condition, the artery 

 has been found divided into two vessels near 

 its commencement, the artery being single 

 above and below. 



In a very few cases the three arteries of 

 the fore ann, radial, ulnar, and interosseous, 

 have arisen together from the end of the 

 brachial trunk, at the usual distance below 

 the elbow. 



Hiffh division. — The most frequent change 

 from the ordinary ari'angement of the 

 brachial artery is connected with its division 

 into terminal branches. 



Out of 481 examples recorded by Richard 

 Quain from observations made, some on the 

 right and some on the left side of the body, 

 the vessel was found in .^86 to divide at its 

 usual position, a little below the elbow- joint. 

 In one case only (and that complicated by 

 anothei- peculiarity, viz., the existence of a 

 rtis ahcvTcinf; proceeding from the axillaiy to 

 the radial), was the place of division lower 

 than usual, being between two and three 

 inches lower than the elbow-joint. In 04 

 cases the brachial artery divided above the 

 usual point, at various heights upwards to 

 the lower border of the axilla. The branch 

 prematurely separated from the rest of the 

 trunk in an early division, is, in the pro- 

 portion of nearly three cases out of four. 



u D 2 



