Extensors Flashcards
True of false: The Abductor Pollicus Longus extends the thumb at the interphallengial joint
False: It cannot help at the IP joint because it attaches at the base of the 1st metacarpal (thumb)
Your patient is unable to extend their IP joint at the thumb, what tendon is most likely injured?
The Extensor Pollicis LONGUS tendon
(It’s the only tendon to pass over the IP joint at the thumb, Brevis does not)
Which tendon compartment moves places depending on where you take a cross section of the wrist?
Synovial Sheath 3 (with extensor pollicis longus)
De Quervian’s Tenosynovitis is also called ______ and is caused by ______
It is common in who?
“Texting thumb”
Cumulative Trauma disorder of tendons in 1st dorsal compartment.
Common in new mothers.
When you have a spinal cord injury at what level, are you limited to only being able to extend the wrist?
An injury between C7 and C8 (C7 spinal nerve injury)
Distal radius fracture: A volar displacement of bone is called what?
A smith fracture
Distal radius fracture: What is Dorsal displacement of the bone called?
Colles’ fracture
What is the name of bone 1 and 2?
- Pisiform
- Triquetrum
What is the name of bone 3 and 4?
- Lunate
- Scaphoid
What is the name of bone 5 and 6?
- Trapezium
- Trapezoid
What is the name of bone 7 and 8?
- Capitate
- Hamate
The mid-carpal joint classifies as a ______ joint
ellipsoid joint and functions “Bi-axial”
True or false: : The mid-carpal joint does: flexion, extension, radial
deviation, ulnar deviation,** and
circumduction **
True, it circumducts with the radiocarpal jt
What are the two ligaments of the Distal Radioulnar joint?
Volar radioulnar ligaments
Dorsal radioulnar ligaments
What carpal joints help with Radius/ulnar deviation?
Radiocarpal Joint and Midcarpal Joint
Name the 3 parts of a Metacarpal and a Phalange
- Base
- Shaft
- Head
There are ___ Metacarpals and ___ phalanges?
5 Metacarpals
14 Phalanges
Name structure 1 and 2
- Dorsal Radio-ulnar ligament
- Triangular fibrocartilage complex (TFCC)
Carpometacarpal Joints of the Fingers do what action?
Volar and Dorsal gliding
Extrinsic muscles of the hand can ______ whereas instrinsic muscles are for ______
Extrinsic: Generate greater force
Intrinsic: For precise control
Name these 2 muscles
Which one is more lateral?
Which one is more superficial?
Left: Extensor Carpi Radialis Longus
Right: Extensor Carpi Radialis Brevis
Longus is more lateral and superficial
What two muscles are involved in tennis elbow?
Extensor Carpi Radialis Longus and Brevis
What are the muscle actions of Extensor Carpi Radialis Longus and Brevis
Extend the wrist
Radial Deviation
Longus is active during fist clenching aswell
What is the proximal attachment of Extensor Carpi Radialis Longus?
What about for Brevis?
Longus: Lateral supra-epicondylar ridge of humerus
Brevis- Common extensor tendon to the Lateral Epicondyle of Humerus
What is the distal attachment of Extensor Carpi Radialis Longus
base of the 2nd metacarpal
What is the distal attachment of Extensor Carpi Radialis Brevis
base of the 3rd metacarpal
What is the innervation of all wrist extensor muscles
Radial Nerve
What is the distal attachment of Extensor Digitorum
Extensor expansions of the medial 4 digits.
What is the innervation of extensor digitorum?
Deep branch of Radial Nerve C7 C8
What is the Proximal attachment of Extensor Digitorum?
Lateral epicondyle of the humerus
(common extensor tendon)
What is the proximal attachment of Extensor Digiti Minimi?
Lateral epicondyle of humerus
(common extensor origin)
What is the distal attachment of Extensor Digiti Minimi
Extensor expansion of 5th digit
What is the innervation of extensor digiti minimi?
Radial nerve (deep branch) (C7, C8)
What are the muscle actions of Extensor Carpi Ulnaris
Extend Wrist
Ulnar Deviation
Active during fist clenching
What is the distal attachment of the Extensor Carpi Ulnaris
Base of the 5th metacarpal
What is the innervation of Extensor Carpi Ulnaris
Radial Nerve c7 c8
What is the distal attachment of Extensor Indicis
Extensor expansion of 2nd digit
What is the proximal attachment of Extensor Indicis
Posterior ulna and interosseous
membrane
What is the muscle action of Extensor Indicis
Extend the 2nd digit (MCP joint)
May assist to extend the wrist (radiocarpal joint)
What is the innervation of Extensor indicis
Radial (PIN) C7 and C8
What is the most ventral muscle that the Radial nerve innervates?
Brachioradialis
What 3 muscles are innervated by 2 nerves?
- Lumbricals of hand
- Flexor Pollicus Brevis
- Flexor Digitorum Profundus
