MUSCLE* "/' Till-: A.\Ti:i;l<>l; LlMHs. Ml 



Tin- fleshy bo<ly, not very considerable, and flattened from 

 l.arkwanls extends from the upper extremity of the radius to 

 tin lower fourth of the same bone. The tendon (Fig. ll'.t, If'/;, at first 

 rounded, then flattened, reaches the gliding groove which divides the 

 < \t< -rnal inferior tuberosity of the radius into two portions, passes to the 

 nal side of the carpus, crossing the lateral ligament common to the articu- 

 lati< ins of this region, and arrives at the anterior surface of the principal uieta- 

 carpal bone, where it receives the small tendinous branch detached from the 

 anterior extensor, as well as a strong fibrous band coming from the external 

 >!(! of the carpus (Fig. 119, 17). Afterwards, descending alongside the 

 iuil border of the principal tendon of its congener, and united to it by a 

 fibrous fascia, it gains the articulation of the fetlock, and expanding, ter- 

 m mates at the upper extremity of the first phalanx. 



Att<n -linn nt*. 1, By its muscular body, to the external tuberosity of the 

 radius, the external ligament of the elbow articulation, and to the bodies of the 

 two hones of the fore-arm origin ; 2, By the inferior extremity of its tendon, 

 to the capsule of the nietacarpo-phalaugeal articulation, and in front of the 

 superior t-xtivmity of the first phalanx termination. 



'/(. Its muscular portion, enveloped in a special aponeurotic 

 sheath, responds : in front, to the anterior extensor of the phalanges ; behind, 

 to the external flexor of the metacarpus and the perforatus and perforans 

 muscles ; outwards, to the antibrachial aponeurosis. The tendon, surrounded 

 by a vaginal synovial sheath, in passing over the carpus, covers, beyond the 

 knee, the anterior aspect of the metacarpus, and the anterior ligament of the 

 mt taearpo-phalangeal articulation, over which it glides by means of a small 

 vesicular synovial bursa. It is covered by a slight fibrous fascia, which 

 separates it from the skin, and which is also spread over the tendon of the 

 anterior extensor. 



Action. This muscle is an extensor of the digit, and also concurs in the 

 extension of the entire foot on the fore-arm. 



B. Posterior AntibracJiial Region. 



This is composed of five flexor muscles grouped vertically behind the 



I' the fore-arm. Three are situated superficially, and act on the whole 



these are the external flexor, oblique flexor, and the internal flexor of 



t)& in' -. The other two, fixed to the digit by their inferior extremity, 



ami rnvi red by the preceding, are designated the superficial and deep flexors 



1 . Internal Flexor of the Metacarpus, or Posterior Uliuiris. 1 (Fig. 119, 18.) 



Synonym*. Epicoudylo-flupercarpeus Girard. (Flexor nutacarpi external 

 ru-gupercarpetu externu* Ltyh.) 



Situation. The external flexor of the metacarpus is situated at the ex- 

 ternal side of the fore-arm, between the lateral extensor of the phalanges 

 and the oblique flexor. 



Form Structure Attachments. This muscle is elongated from above to 

 In 1"\\. tlatti -'n -d from one side to the other, thick in its middle part, and 

 int< rsoctod by very strong aponeurotic bands. It commences on the summit 



1 It i* known that tin- IM.HV t mim-nivs, liitln-ito t.Tinol in ut.riiwry uimt>iu\ 

 < 1 -i )iii-iiinl\ li ," roiTt *|N mil : tin- lirM, tu thr r|>iroiiil\ Ic of Man. tin 1 .<* COM, 

 t tin- i |iitn>clil> :i. It lu-.-iI i-M-iti- 110 Mir|in.~ . tin r, I.TI . t MI- thr ilclnuiiili.r 



Irani t" th< n.iiaok'tf of the jKHjU'rior autibrnchiul n-_'ion rhan::.-.! a al- 



