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Bones and joints
level of the wrist joint. The distal transverse crease lies at the level of
• Vertebrae: if a finger is passed down the posterior neck in the mid-
the proximal border of the flexor retinaculum.
line the first bony structure palpated is the spinous process of the 7th
• Anatomical snuffbox: the boundaries are formed medially by ex-
cervical vertebra (vertebra prominens)athe first six spinous processes • Anterior wrist: the proximal transverse crease corresponds to the
are covered by the ligamentum nuchae. tensor pollicis longus and laterally by the tendons of abductor pollicis
• Scapula: the acromion process can be palpated as a lateral extension longus and extensor pollicis brevis.
of the spine of the scapula. The spine, superior angle, inferior angle
and medial border are palpable posteriorly. The coracoid process can Vessels
be palpated below the clavicle anteriorly within the lateral part of the • The subclavian artery can be felt pulsating as it crosses the 1st rib.
deltopectoral triangle (Fig 40.1). • The brachial artery bifurcates into radial and ulnar branches at the
• Clavicle: is subcutaneous and therefore palpable throughout its level of the neck of the radius. The brachial pulse is felt by pressing lat-
length. erally at a point medial to the bicipital tendon (Fig. 40.2). This is the
• Humerus: the head is palpable in the axilla with the shoulder pulse used when taking blood pressure measurements.
abducted. The lesser tuberosity can be felt lateral to the coracoid pro- • At the wrist the radial artery courses on the radial side of flexor carpi
cess. When the arm is externally and internally rotated the lesser radialis (Fig. 40.4) and the ulnar artery and nerve course on the radial
tuberosity can be felt moving next to the fixed coracoid process. side of flexor carpi ulnaris. The pulses of both are easily felt at these
• Elbow: the medial and lateral epicondyles of the humerus and ole- points. The radial artery can also be felt in the anatomical snuffbox.
cranon process of the ulna can be palpated in line when the elbow is • The superficial palmar arch is impalpable and reaches as far as the
extended. With the elbow flexed they form a triangle. This assumes proximal palmar crease. The deep palmar arch reaches a point approx-
importance clinically in differentiating supracondylar fractures of the imately one fingerbreadth proximal to the superficial arch.
humerus, where the ‘triangle’ is preserved, from elbow dislocations • The dorsal venous network (on the dorsum of the hand) drains later-
where the olecranon comes into line with the epicondyles. ally into the cephalic vein and medially into the basilic. These veins can
• Radius: the radial head can be felt in a hollow distal to the lateral be identified in most lean subjects. The median cubital vein is usually
epicondyle on the posterolateral aspect of the extended elbow. The visible in the cubital fossa.
head can be felt rotating when the forearm is pronated and supinated.
• Ulna: the posterior border is subcutaneous and therefore palpable. Nerves
• Wrist: the styloid processes of the radius and ulna are palpable. The The ulnar nerve can usually be rolled as it courses behind the medial
dorsal tubercle (of Lister) can be felt on the posterior aspect of the dis- epicondyleaan important point when considering surgical approaches
tal radius. to the elbow and fractures of the medial epicondyle.
• Hand: the pisiform can be palpated at the base of the hypothenar The surface markings of impalpable nerves must be known for safe
eminence. The hook of the hamate can be felt on deep palpation in the surgical incisions. These correspond to:
hypothenar eminence just distal to the pisiform. The scaphoid bone can • Axillary nerve: winds around behind the surgical neck of the
be felt within the anatomical snuffbox (Fig, 40.5). humerus.
• Radial nerve: crosses from medial to lateral behind the humeral
The soft tissues shaft at its midpoint.
• Axilla: the anterior axillary fold (formed by the lateral border of pec- • Posterior interosseous branch (of radial nerve): winds around the
toralis major) and the posterior axillary fold (formed by latissimus dorsi radius three fingerbreadths distal to the head of the radius.
as it passes around the lower border of teres major) are easily palpable • Median nerve (at the wrist): lies in the midline, just lateral to the ten-
(Fig. 40.1). don of palmaris longus.
• Pectoralis major: contracts strongly during arm adduction (Fig. • Ulnar nerve (at the wrist): lies immediately medial to the ulnar
40.3); this is useful in the examination of breast lumps. artery.
• Breast: the base of the breast overlaps the 2nd to 6th ribs and extends
from the sternum to the mid-axillary line. The nipple (in males) usually
overlies the 4th intercostal space.

Surface anatomy of the upper limb 91