Wrist Articulations Flashcards
What is the Wrist complex formed by?
Radiocarpal (attaches hand to forearm) and mid-carpal joints
What forms the radiocarpal joint?
Distal radius and the radioulnar articular disc which connects the medial aspec of the distal radius to the distal ulna
Distal Joint surface is formed by the catholic, lunate and triquetrum.
What is the osteokinematic motion of the Radiocarpal joint?
- Flexion/extension
2. Radial/Ulnar Deviation
Loose packed position of the radiocarpal joint?
Neutral w/ slight ulnar deviation
Close packed position of the radiocarpal joint?
Extension with radial deviation
Capsular Pattern of the Radiocarpal Joint?
Flexion + Extension are equally limited
What is the anatomic snuffbox?
Depression found on the dorsal surface of the wrist near the distal radius
What structures border the anatomical snuffbox?
Tendons of the : (brevis sandwich)
- abductor pollicis longus
- Extensor pollicis brevis
- Extensor pollicis longus
What is the anatomical snuffbox often used for?
Palpation of the scaphoid when there is concern for Fx.
Where is carpal tunnel located?
Located close to the deep surface of the flexor Retinaculum.
What nerve passes through the carpal tunnel?
Median Nerve
Where is the dorsal radiocarpal ligament located?
Only major ligament located on the dorsal surface of the wrist.
Originates on the posterior surface of the distal radius and styloid process of the radius + attaches to the lunante and triquetrum
What is the purpose of the Dorsal radiocarpal ligament?
Limits wrist flexion
What does the extensor retinaculum cross?
Dorsal aspect of the wrist, covering the tendons of the extensor musculature.
What is the purpose of the extensor retinaculum?
Prevents the tendons form ‘bowstringing’ as the wrist extends
Where does the flexor retinaculum cross (transvers carpal ligament) ?
Crosses the palmar aspect of the wrist, forming the most anterior aspect of the carpal tunnel.
What is the purpose of the flexor retinaculum?
To prevent ‘bowstringing’ as the wrist is flexed. It also serves an an attachment site for thenar and Hypothenar muscles
Where does the interosseous membrane run?
Runs obliquely form the radius to the ulna
What is the purpose of the interosseous membrane?
Spans from the proximal radioulnar jt to the distal radioulnar jt and serves as a stabilizer against Axial forces applied to the wrist
Where is the Palmar radiocarpal ligament located?
Originates from the anterior surface of the distal radius and attaches to the capitate, triquetrum, and scaphoid
What is the purpose of the Palmar radiocarpal ligament?
Maintains alignment of the associated joint structures + limits hyperextension of the wrist
Where is the radial collateral ligament of the wrist located?
Originates form the styloid process of the radius and inserts on the scaphoid and trapezium
What is the purpose of the radial collateral ligament of the Wrist?
Serves to limit ulnar deviation + becomes taut when the wrist is in extremes of extension and flexion
What is the Triangular fibrocartilage complex (TFCC)?
Cartilaginous disc that sits between the ulna, lunate, and triquetrum.
What is the purpose of the triangular fibrocartilage complex (TFCC)?
Provides stability to the wrist joint, connecting the radius and ulna together and allowing for better distribution of forces thru the wrist
What is the tunnel of guyon?
Space that is located b/t the hook of the hamate, pisiform, palmar carpal ligament and flexor retinaculum.
What is the purpose of the Tunnel of Guyon?
Provides passage for the ulnar nerve and artery as they enter the hand.
Compression can cause ulnar tunnel syndrome
