Henry Gray (18251861). Anatomy of the Human Body. 1918.
of the scapula and extend to the third and fifth ribs respectively, just lateral to the corresponding costal cartilages. On the front of the elbow-joint a triangular spacethe anticubital fossais mapped out for convenience of reference. The base of the triangle is a line joining the medial and lateral epicondyles, while the sides are formed respectively by the salient margins of the Brachioradialis and Pronator teres.
FIG. 1234 The mucous sheaths of the tendons on the back of the wrist. (See enlarged image)
FIG. 1235 Front of right upper extremity, showing surface markings for bones, arteries, and nerves. (See enlarged image)
Mucous Sheaths.On the volar surfaces of the wrist and hand the mucous sheaths of the Flexor tendons (Fig. 1233) can be indicated as follows. The sheath for Flexor pollicis longus extends from about 3 cm. above the upper edge of the transverse carpal ligament to the terminal phalanx of the thumb. The common sheath for the Flexores digitorum reaches about 3.5 to 4 cm. above the upper edge of the transverse carpal ligament and extends on the palm of the hand to about the level of the centers of the metacarpal bones. The sheath for the tendons to the little finger is continued from the common sheath to the base of the terminal phalanx of this finger; the sheaths for the tendons of the other fingers are separated from the common sheath by an interval; they begin opposite the necks of the metacarpal bones and extend to the terminal phalanges. The mucous sheaths of the Extensor tendons are shown in Fig. 1234 (see alos page 459).
FIG. 1236 Back of right upper extremity, showing surface markings for bones and nerves. (See enlarged image)
Arteries (Fig. 1235).The course of the axillary artery can be marked out by abducting the arm to a right angle and drawing a line from the middle of the clavicle to the point where the tendon of the Pectoralis major crosses the prominence of the Coracobrachialis. Of the branches of the axillary artery, the origin of the thoracoacromial corresponds to the point where the artery crosses the upper border of Pectoralis minor; the lateral thoracic takes practically the line of the lower border of Pectoralis minor; the subscapular is sufficiently indicated by