THE UPPER EXTREMITY. 73 



Radial artery at the wrist, 574-5-6; Fig. 358. (563-4-5) 

 Relations. 



Branches of the radial artery at the wrist : 

 Posterior radial carpal : 



Second and third dorsal interosseous arteries. 



Dorsal digital branches. 

 Metacarpal, or first dorsal interosseous artery : 



Dorsal digital arteries. 

 Dorsalis pollicis. 

 Dorsalis indicis. 



Open and demonstrate the compartments of the posterior annular ligament. 



Posterior annular ligament, 1206. (1181-2) 

 Back of the wrist and hand, 1210. (1186) 

 Transverse ligament, 255 ; Fig. 236. (260) 



Divide the transverse ligament, separate the metatarsal bones and expose the interossei muscles and per 

 furating or communicating arteries. 



The interossei, 356-7-8 ; Figs. 281-2. 

 Three palmar interossei : 



Origin. Insertion. Structure. Nerve-supply. 

 Four dorsal interossei : 



Origin. Insertion. Structure. Nerve-supply. 

 Action of the interossei muscles. Relations. Variations. 

 Posterior, communicating, or perforating arteries, 579 ; Fig. 359. (568) 



The muscles of the shoulder, arm, forearm, and hand should now be removed. On the forearm re- 

 move the supinator brevis last. The removal of the structures should be made a process of careful re- 

 view, and as each muscle is removed, the student should note again the origin, insertion, structure, 

 actions, etc., especially of the deeper muscles, which are fully exposed as the superficial muscles are 

 removed. Demonstrate the arterial anastomoses about the elbow joint. The ligaments of the joints 

 should then be exposed and demonstrated, and the structure of the joints studied. 



Arterial anastomoses about the elbow joint, 1191-2. (116-7-8) 

 Supinator radii brevis, 346-7. (346-7-8) 

 Origin. Insertion. Action. 



Articulations. 



The various kinds of articulations, 187-8. (196-7) 

 Synarihrosis : 



True sutures. 



False sutures. 



Grooved sutures. 

 Amphiarthrosis. 

 Diarthrosis : 



Arthrodia. 



Ginglymus. 



Ginglymo-arthrodial. 



Enarthrodia. 



Trochoides. 



The various movements of joints, 188-9. (197-8) 

 Gliding. 

 Angular. 

 Rotation. 

 Circumduction. 



Articulations of the Upper Extremity. 

 Scapulo-clavicular union, 230-1-2-3. (236-7-8-9) 

 (a) Acromio clavicular articulation. 

 (l>) Coraco-clavicular ligaments. 

 (f) Proper scapular ligaments. 



Coraco-acromial and transverse. 

 6 



