Upper Extremity: Hand Flashcards
How many Carpal Bones are there?
8 Scaphoid, Lunate, Triquestrum, Pisiform, Trapezium, Trapezoid, Capitate, Hamate
Which bones make up the carpal tunnel?
Ulnar Side: Pisiform and Hook of Hamate
Radial Side: Tubercle of Scaphoid, Crest of Trapezium
Which Ligament keeps the metacarpal head together?
Deep Transverse Metacarpal Ligament
What structure is continuous with the deep transverse metacarpal ligament?
Palmar Plate
Do you get more or less abduction/adduction of the fingers when the MCP joint is flexed and why?
When flexed, the massive collateral ligaments are tight. This prevents side to side movement.
Do the IP and the MCP joints both allow flexion/extension as well as ab/adduction?
No, the MCP joint allows both, but the Interphalangeal joints allow for flexion/extension only
How many sesamoid bones are there in the thumb MCP joint?
There are normally 2
Does the Thumb MCP joint act more like a digital MCP or IP joint and why?
The thumb MCP joint acts more like an IP joint in that it flexes/extends only
Which bones are involved in the thumb carbo-metacarpal joint?
The Trapezium and the 1st metacarpal
What forms the roof of the carpal tunnel?
Flexor Retinaculum
How many branches of the flexor retinaculum are there and what lies in them?
2 additional small tunnels.
Radial: Flexor Carpi Radialis
Ulnar: Ulnar Artery and Ulnar Nerve
What are the attachments of the extensor retinaculum?
Ulnar Side: Ulna Styloid, Triquestrum, Hamate
Radial Side: Radius
do all the extensor tendons pass through the extensor retinaculum?
Yes
What is the palmar aponeurosis made from, and where does it insert?
It is formed from the flexor retinaculum and palmaris longus. It spans into the lateral aspects of the palmar plate
What is the function of the palmar fascia?
protects nerves and vessels lying underneath
What are the muscles of the deep anterior compartment of the forearm?
- Flexor Digitorum Profundus
- Flexor Pollicis Longus
- Pronator Quadratus
What are the origins and insertion of FDP?
Anterior ulna and Interosseus membrane
Attaches to distal phalanges
What are the origins and insertion of FPL?
Anterior radius and interosseous membrane
Attaches to base of distal phalanx of thumb
Where does Pronator Quadratus lie?
Underneath FDP and FPL between anterior ulna and radius
Which muscles are in the intermediate compartment of the anterior forearm?
- Flexor Digitorum Superficialis
What are the attachments of FDS?
Origin: 2 heads - anterior radius, medial epicondyle of humerus (flexor origin)
Insertion: Middle phalanges of the 4 fingers
What is the innervation of FDP?
ulnar for ulnar half and median for radial half
What is the innervation of FDS?
Median Nerve
Which muscles are in the superficial compartment of the anterior forearm?
- Flexor Carpi Ulnaris
- Palmaris Longus
- Flexor Carpi Radialis
- Pronator Teres
Where do all the muscles of the superficial compartment of the anterior forearm arise?
The flexor origin on the medial epicondyle (ulnar side)
Where does FCU insert?
Pisiform
Where does FCR insert?
Base of metacarpals II & III
Where does Pronator Teres insert?
Midshaft radius to allow for pronation
What are the extensor muscles of the hand?
- Extensor Digitorum Communis
- Extensor Digiti Indices
- Extensor Digiti Minimi
What is the canal of Guyon?
The Ulnar Tunnel with the ulnar nerve and artery, part of the flexor retinaculum
