MUSCLES OF THE RIGHT SUPERIOR LIMB 



55 



Cranial Side 



'MSN 



22. Triceps brachii (t. extensor cubiti) m.: Scapula and 

 humerus; to olecronal process of ulna. Extends antibrachium 

 and thus is antagonistic to the biceps and brachialis muscles 

 (20, 21). 



22^. Caput laterale (ectotriceps) : 

 Arises from the region of greater tuber- 

 cle of humerus. 



2 2&. Caput longum (meditriceps, 

 anconeus longus) : Arises from the axil- 

 lary border of scapula. 



22c. Caput mediale (entotriceps, 

 anconeus medialis, anconeus poster- 

 ior) : Arises from the dorsal surface of 

 humerus. 



E. MUSCLES WHICH MOVE 

 THE HAND 



(Nos. 23-31; Fig. 20) 



There are some ten flexors and exten- 

 sors of the wrist and hand which arise Fig.iq.— Crosssectionprox- 

 from the humerus or radius and ulna r! ^1; Whl^u't^l "et 



near the elbow, in addition to those brachial a.; BI, biceps brachii; 

 , . , . r .1 1 1 1 BV, brachial v.; C, clavodel- 



which arise from the carpals and meta- toid, inserting end of; cv, ce- 

 carpals and insert on the phalanges. p^^IJ'^^:;;:^^^' f . epitrochiearis 



^ / \ rn';ECT,ectotricepsm.;ENT, 



In general the extensors (Nos. 23-27) entotriceps; H, humerus; 



J ,-i . , J T ,1 • 1 MET, meditriceps; MN, me- 



and their tendons he on the cranial or ^^^^ ^ . ^sn, muscuiospirai 

 dorsal side of the antibrachium and n.; sr, superficial radial n.; 



, . UN, ulnar n. 



hand while the flexors (Nos. 28-31) and 



their tendons lie on the volar or caudal side. The tendons of 

 both groups of muscles are held firmly in place at the wrist and 

 finger joints by bands of tough connective tissue, forming annu- 

 lar ligaments, through which these tendons ghde freely. In 

 order to understand the functions and general mechanical rela- 

 tions of annular ligaments and tendon sheaths, the student 

 should expose the one on the dorsum of the carpus (Fig. 20, AL) 



