Important construction points of the arm, forearm, hand:
Medial condyle of humerus
Head of radius (when arm extended)
Olecranon process of ulna
Crest of ulna (ulnar furrow)
Styloid process of ulna (marks lower end of forearm)
Lateral edge at distal end of radius
Carpal mass (seen as slight mound on dorsal side of wrist)
Heads of metacarpals (knuckles)
Joints of phalanges