Anterior Forearm Muscles (Quiz 1) Flashcards
What are the 8 muscles of the anterior compartment of the forearm?
1) pronator teres
2) flexor carpi radialis (FCR)
3) palmaris longus
4) flexor carpi ulnaris (FCU)
5) flexor digitorum superficialis (FDS)
6) flexor digitorum profundus (FDP)
7) flexor pollicis longus (FPL)
8) pronator quadratus
What are the 2 heads of the pronator teres?
ulnar head and humeral head
What are the 2 heads of the flexor carpi ulnaris (FCU)?
humeral head and ulnar head
What are the 2 heads of the flexor digitorum superficialis (FDS)?
humero-ulnar head and radial head
What are the 2 parts of the flexor digitorum profundus (FDP)?
medial part and lateral part
There are _____ muscles crossing over the elbow joint, some of which act on the elbow joint exclusively, whereas others act as the wrist and fingers
17
The flexor muscles of the forearm are arranged in 3 layers/groups. What are they?
1) superficial layer (contains 4 muscles)
2) intermediate layer (1 muscle)
3) deep layer (3 muscles)
What are the 4 muscles in the superficial layer of the anterior compartment flexor forearm muscles?
1) pronator teres
2) flexor carpi radialis
3) palmaris longus
4) flexor carpi ulnaris
(these muscles are all attached proximally by a common flexor tendon to the medial epicondyle of the humerus, the common flexor attachment
What is the 1 muscle in the intermediate layer of the anterior compartment flexor forearm muscles?
flexor digitorum superficialis
What are the 3 muscles in the deep layer of the anterior compartment flexor forearm muscles?
1) flexor digitorum profundus
2) flexor pollicis longus
3) pronator quadratus
What is the origin/proximal attachment of the ulnar head of the pronator teres?
coronoid process of the ulna
What is the origin/proximal attachment of the humeral head of the pronator teres?
medial epicondyle of the humerus (common flexor origin)
What is the insertion/distal attachment of the pronator teres?
middle of convexity of lateral surface of radius
What innervates the pronator teres?
medial n.
What is the action of the pronator teres?
pronates and flexes forearm at the elbow
What is the origin/proximal attachment for the flexor carpi radialis (FCR) and palmaris longus ?
medial epicondyle of the humerus (common flexor origin)
What is the insertion/distal attachment of the flexor carpi radialis (FCR)?
base of 2nd metacarpal
What innervates the flexor carpi radialis (FCR) and palmaris longus?
median n.
What is the action of the flexor carpi radialis (FCR)?
flexes and abducts hand at the wrist
What is the insertion/distal attachment for the palmaris longus?
distal half of flexor reticulum and apex of palmar aponeurosis
What is the action of palmaris longus?
flexes hand at the wrist and tenses palmar aponeurosis
What muscle is absent in 14% of the population?
palmaris longus
What is the origin/proximal attachment for the humeral head of the flexor carpi ulnaris (FCU)?
medial epicodyle of the humerus (common flexor origin)
What is the origin/proximal attachment for the ulnar head of the flexor carpi ulnaris (FCU)?
olecranon and posterior border of the ulna via aponeurosis
What is the insertion/distal attachment for the flexor carpi ulnaris (FCU)?
-pisiform
-hook of hamate
-5th metacarpal
What innervates the flexor carpi ulnaris (FCU)?
potential test q
ulnar n.
What is the action of the flexor carpi ulnaris (FCU)?
flexes and adducts the hand at the wrist
What is the origin/proximal attachment of the humeral-ulnar head of the flexor digitorum superficialis (FDS)?
medial epicondyle of the humerus (common flexor origin and coronoid process of the ulna)
What is the origin/proximal attachment of the radial head of the flexor digitorum superficialis (FDS)?
superior half of anterior border of radius
What is the insertion/distal attachment of the flexor digitorum superficialis (FDS)?
shafts of middle phalanges of medial 4 digits
What innervates the flexor digitorum superficalis (FDS)?
median n.
What are the actions of the flexor digitorum superficalis (FDS)?
-flexes middle phalanges at proximal interphalangeal joints of middle 4 digits
-acting more strongly, it also flexes proximal phalanges at metacarpophalangeal (MCP) joints
-allows you to grip cup, remote, etc.
What is the origin/proximal attachment of the flexor digitorum profundus (FDP)?
proximal three quarters of medial and anterior surfaces of the ulna and interosseous membrane
What is the insertion/distal attachment for the medial part of the flexor digitorum profundus (FDP)?
bases of distal phalanges of 4th and 5th digits
What is the insertion/distal attachment for the lateral part of the flexor digitorum profundus (FDP)?
bases of the distal phalanges of 2nd and 3rd digits
What innervates the medial part of the flexor digitorum profundus (FDP)?
ulnar n.
What innervates the lateral part of the flexor digitorum profundus (FDP)?
median n.
What are the actions of the flexor digitorum profundus (FDP)?
medial part
-flexes distal phalanges 4 and 5 at distal interphalangeal joints
lateral part
-flexes distal phalanges 2 and 3 at distal interphalangeal joints
What muscle is the only muscle that can flex the distal interphalangeal joints of the fingers?
flexor digitorum profundus (FDP)
The flexor digitorum profundus flexes the distal phalanges of the medial 4 fingers after the _____________________ has flexed their middle phalanges (it curls the fingers and assists with flexion of the hand, making a fist)
flexor digitorum superficalis
The flexor digitorum profundus can flex only the ________ finger independently, thus the fingers can be independently flexed at the proximal but not the distal interphalangeal joints
index
What are the nerve tests within the flexor digitorum profundus?
median n. test
-check strength of proximal forearm, specifically the index finger
ulnar n. test
-check strength of pinky finger
What is the origin/proximal attachment of the flexor pollicis longus (FPL)?
anterior surface of radius and adjacent interosseous membrane
What is the insertion/distal attachment of the flexor pollicis longus (FPL)?
base of distal phalanx of thumb
What innervates the flexor pollicis longus (FPL)?
median n.
What are the actions of the flexor pollicis longus (FPL)?
-flexes phalanges of the 1st digit (thumb)
-only muscle that flexes the interphalanageal joint of the thumb
-may assist in flexion of the wrist joint
What is the origin/proximal attachment of the pronator quadratus?
distal quarter of the anterior surface of the ulna
What is the insertion/distal attachment of the pronator quadratus?
distal quarter of the anterior surface of the radius
What innervates the pronator quadratus?
median n.
What are the actions of the pronator quadratus?
potential test q
-pronates forearm (deep fibers bind radius and ulna together)
-prime mover for pronation
What muscle is the only muscle that attaches to only the ulna at one end and only the radius at the other end?
pronator quadratus