Dorsal Forearm And Hand Flashcards
Name the carpal bones
Scaphoid, Lunate, Triquetrum, Pisiform, Trapezium, Trapezoid, Capitate, Hamate
What artery would be damaged with a fracture above the epicondyles?
Brachial artery
What type of joint is the DRUJ?
Synovial pivot
Supination and pronation
What is the role of the TFCC in the DRUJ?
Binds ends of radius and ulna together
What is the functional importance of the DRUJ?
Helps transmit loads from hand to forearm
Superficial (6) muscles of posterior forearm
Brachioradialis ECRL ECRB Extensor digitorum Extensor digiti minimi ECU
Deep muscles (5) of posterior forearm
Supinator APL EPL EPB Extensor indicis
1st posterior compartment
EPB (extensor pollicis brevis)
APL (abductor pollicis longus)
2nd posterior compartment
ECRL (extensor carpi radialis longus)
ECRB (extensor carpi radialis brevis)
3rd posterior compartment
EPL (extensor pollicis longus)
4th posterior compartment
Extensor digitorum
5th posterior compartment
EDM (extensor digiti minimi)
6th posterior compartment
ECU (extensor carpi ulnaris)
Contents of snuffbox
EPL EPB Scaphoid Radial artery Superficial radial nerve
Which two muscles extend wrist on radial side?
ECRL and ECRB
Which two muscles both extend and abduct thumb?
APL and EPB
What muscles are involved with lateral epicondylosis (tennis elbow)?
Extensors attached to lateral epicondyle
Specifically ECRB
What is the cause and effect of tennis elbow?
Cause: overuse injury
Effects: pain with wrist extension, pain on lateral side of elbow, weak grip, weakness in scapular muscles
What nerve is damaged with Wrist Drop and what is a possible cause of this?
Radial nerve
Spiral fracture of humerus
What is DeQuervain’s Syndrome and it’s symptoms?
Inflammation of structures in 1st posterior compartment (EPB and APL)
Stretching causes increased pain
Who does DeQuervain’s syndrome usually effect? How is it tested?
New Mothers and day care workers
(Hand extended and abducted when holding babies)
Will hurt when wrapping fingers around thumb and then flexing toward ulna
What is the functional purpose of the dorsal tubercle of the radius?
Allows passage of tendons of the forearm
Serves as trochlear pulley for tendon of long extensor of thumb
What is the functional purpose of the extensor retinaculum?
Prevents bow stringing of tendons when hand is extended
What is the purpose of synovial tendon sheaths?
Covers tendons on dorsal wrist to Reduce friction for tendons when traversing attachment of extensor retinaculum
What are intertendinous connections in the fingers and what do they restrict?
Link adjacent tendons to MCP joints
Restrict independent extension of fingers
*why one finger can’t stay flexed as others are extended
What separates the cavity of DRUJ from the cavity of the wrist joint?
Articular disc
What is the purpose of the sacciform recess in the DRUJ?
Extension of synovial membrane that accommodates twisting of capsule during pron/supin
What muscles are involved with supination of the DRUJ?
Supinator (no resistance)
Biceps brachii (resistance)
EPL and ECRL (some assistance)
What muscles are involved with pronation of the DRUJ?
Pronator quadratus (primary) Pronator teres (secondary) FCR, palmaris longus, brachioradialis (some assistance)...when 1/2 pronated
