DISSECTION OF THE UPPER EXTREMITY 



109 



mentum capitulorum [ossium metacarpalium] transversum). 

 Note that the Mm. lumbricales run volar and the Mm. interossei 

 dorsal to this ligament. 



Study the form, position, origin, insertion, action, and inner- 

 vation of 



(a) Volar interosseous muscles (Mm. interossei volares I., II., III.). 



(b) Dorsal interosseous muscles (Mm. interossei dor sales I.-IV.). 



Eeflect the radial head of the M. interosseus dorsalis I. A 

 good dorsal view of the deep head of the M. flexor pollicis brevis 



V. mediana basilica -- s 



N. cutaneus anti- 

 brachii medialis --- - 



N. / 



medianus ------ 7^ 



A. of the 

 N. med.-- 

 M. brach. --- 

 M. pronat.. - 

 teres 



M. palm. 

 long. 



M. flex. _ 

 sub. dig. 



A. collat. 

 uln. sup. 



N. ulnaris - - 



M. flexor - - 

 carpi ulnaris 



Bursa subcutanea olecrani 



FIG. 41. 



/ A. brachialis 

 / /- - V. mediana cephalica 



. . N. muscnlocutaneus 

 Tendon of the 

 _.M. biceps 

 \ M. brachio- 



" " " radian's 

 tTV " "N. radialis 

 i-A.recurrens 

 ^ radialis 



-Capsula 



articularis 

 -M. extensor 

 carpi rad. 

 longus 



- - -M. extensor 

 carpi rad. 

 brevis 



A. interosseus 



recurrens 



Common tendon of 

 origin of extensors 



M. anconaeus 



Olecranon 



Transverse section of the left elbow (after Farabo3uf). The distal end of the humerus is seen intact. 

 (From Poirier et Charpy, TraitS d'Anat. hum., Paris, 1899, 2 ed., t. i. p. 645, Fig. 655.) 



can now be obtained. How does this head arise? Where is it 

 inserted? This part of the M. flexor pollicis brevis was desig- 

 nated by Henle the M. interosseus volaris primus. 



The course of the tendon of the M. flexor radialis should now 

 be followed and its exact insertion established. 



JOINTS. 



Elbow-joint (Articulatio cubiti). (Figs. 41, 42, and 43.) 



The muscles about the elbow may now be completely removed. 

 Leave the M. supinator in position after removal of the others, 

 in order that its exact origin, insertion, innervation, and mode 



