- Discussion:
- at wrist, Lister's tubercle is palpable on dorsum of radius;
- it serves as a pulley for the
EPL;
- radial and
ulnar styloid processes are also palpable, w/ tip of radial styloid process projecting 1 cm distal to that of ulna;
- on ulnar side of Lister's tubercle contains EPL, which defines ulnar border of
anatomic snuff box;
- at point where
EPL passes dorsal radial tubercle (Lister's),
tendon takes a 45 deg turn around tubercle;
- then after passing over
ECRL &
ECRB tendons of tunnel II, it continues along its course to the thumb;
- Exam:
- palpate length of tendon, look for any signs of rupture;
- if dorsal radial tubercle has been disrupted by
Colles Frx (producing irregularity of process),
EPL tendon may rupture due to
added friction imposed upon it as it turns around roughned tubercle;
- Lister's tubercle which is key to identifying both dorsal wrist ganglia & junction of
scapholunate joint & dorsal scapholunate interosseous ligament;
