Two tendons only are conspicuous at the front of the wrist (Fig. X, 2,1.)—the palmaris longus in the middle line, and the flexor carpi radialis to the outer side of the palmaris longus. The flexor carpi ulnaris can, however, be distinguished by palpation along the ulnar border of the forearm, (Fig. X, 4,5.) and can be traced downwards to its insertion into the pisiform bone. Between the palmaris longus and the flexor carpi ulnaris the main mass of the flexor sublimis digitorum lies. Two transverse creases are seen in this situation, the upper of which roughly corresponds to the level of the radio-carpal joint, (Fig. X, 6.) whilst the lower represents almost exactly the upper limit of the anterior annular ligament. Just external to where the flexor carpi radialis tendon cuts across the two transverse creases there is a depression, (Fig. XI, 4.) in the floor of which the lower end of the radius and the tubercle of the scaphoid bone may be felt. The radial artery crosses this space in a downward and outward direction. The trapezium lies at the lower limit of the depression, (Fig. XI, 3.) immediately below and external to the scaphoid tuberosity.
The prominent pisiform bone can be distinguished by tracing downwards the tendon of the flexor carpi ulnaris muscle, (Fig. XI, 1.) and posterior to this bone both cuneiform and unciform bones are situated. A finger's breadth below and external to the pisiform bone deep palpation will verify the position of the hook of the unciform bone. (Fig. XI, 2.)
The anterior annular ligament is attached to four bony points, two on the radial side, (Fig. XI, 5.) the scaphoid tubercle and the ridge on the trapezium, and two on the ulnar side, the pisiform and the hook of the unciform. The upper limit of the ligament corresponds to the lower of the two transverse creases in front of the wrist, (Fig. XI, 6.) whilst the inferior limit of the ligament lies about 3/4 inch below.