Extensor Muskels

Question 1

True of false: The Abductor Pollicus Longus extends the thumb at the interphallengial joint

Answer 1

False: It cannot help at the IP joint because it attaches at the base of the 1st metacarpal (thumb)

Question 1

Your patient is unable to extend their IP joint at the thumb, what tendon is most likely injured?

Answer 1

The Extensor Pollicis LONGUS tendon

(It’s the only tendon to pass over the IP joint at the thumb, Brevis does not)

Question 2

Which tendon compartment moves places depending on where you take a cross section of the wrist?

Answer 2

Synovial Sheath 3 (with extensor pollicis longus)

Question 3

De Quervian’s Tenosynovitis is also called ______ and is caused by ______

It is common in who?

Answer 3

“Texting thumb”

Cumulative Trauma disorder of tendons in 1st dorsal compartment.

Common in new mothers.

Question 4

When you have a spinal cord injury at what level, are you limited to only being able to extend the wrist?

Answer 4

An injury between C7 and C8 (C7 spinal nerve injury)

Question 5

Distal radius fracture: A volar displacement of bone is called what?

Answer 5

A smith fracture

Question 6

Distal radius fracture: What is Dorsal displacement of the bone called?

Answer 6

Colles’ fracture

Question 7

What is the name of bone 1 and 2?

Answer 7

1. Pisiform
2. Triquetrum

Question 8

What is the name of bone 3 and 4?

Answer 8

3. Lunate
4. Scaphoid

Question 9

What is the name of bone 5 and 6?

Answer 9

5. Trapezium
6. Trapezoid

Question 10

What is the name of bone 7 and 8?

Answer 10

7. Capitate
8. Hamate

Question 11

The mid-carpal joint classifies as a ______ joint

Answer 11

ellipsoid joint and functions “Bi-axial”

Question 12

True or false: : The mid-carpal joint does: flexion, extension, radial
deviation, ulnar deviation,** and
circumduction **

Answer 12

True, it circumducts with the radiocarpal jt

Question 13

What are the two ligaments of the Distal Radioulnar joint?

Answer 13

Volar radioulnar ligaments

Dorsal radioulnar ligaments

Question 14

What carpal joints help with Radius/ulnar deviation?

Answer 14

Radiocarpal Joint and Midcarpal Joint

Question 15

Name the 3 parts of a Metacarpal and a Phalange

Answer 15

1. Base
2. Shaft
3. Head

Question 16

There are ___ Metacarpals and ___ phalanges?

Answer 16

5 Metacarpals

14 Phalanges

Question 17

Name structure 1 and 2

Answer 17

1. Dorsal Radio-ulnar ligament
2. Triangular fibrocartilage complex (TFCC)

Question 18

Carpometacarpal Joints of the Fingers do what action?

Answer 18

Volar and Dorsal gliding

Question 19

Extrinsic muscles of the hand can ______ whereas instrinsic muscles are for ______

Answer 19

Extrinsic: Generate greater force

Intrinsic: For precise control

Question 20

Name these 2 muscles

Which one is more lateral?

Which one is more superficial?

Answer 20

Left: Extensor Carpi Radialis Longus

Right: Extensor Carpi Radialis Brevis

Longus is more lateral and superficial

Question 21

What two muscles are involved in tennis elbow?

Answer 21

Extensor Carpi Radialis Longus and Brevis

Question 22

What are the muscle actions of Extensor Carpi Radialis Longus and Brevis

Answer 22

Extend the wrist

Radial Deviation

Longus is active during fist clenching aswell

Question 23

What is the proximal attachment of Extensor Carpi Radialis Longus?

What about for Brevis?

Answer 23

Longus: Lateral supra-epicondylar ridge of humerus

Brevis- Common extensor tendon to the Lateral Epicondyle of Humerus

Question 24

What is the distal attachment of Extensor Carpi Radialis Longus

Answer 24

base of the 2nd metacarpal

Question 25

What is the distal attachment of Extensor Carpi Radialis Brevis

Answer 25

base of the 3rd metacarpal

Question 26

What is the innervation of all wrist extensor muscles

Answer 26

Radial Nerve

Question 27

What is the distal attachment of Extensor Digitorum

Answer 27

Extensor expansions of the medial 4 digits.

Question 28

What is the innervation of extensor digitorum?

Answer 28

Deep branch of Radial Nerve C7 C8

Question 29

What is the Proximal attachment of Extensor Digitorum?

Answer 29

Lateral epicondyle of the humerus
(common extensor tendon)

Question 30

What is the proximal attachment of Extensor Digiti Minimi?

Answer 30

Lateral epicondyle of humerus
(common extensor origin)

Question 31

What is the distal attachment of Extensor Digiti Minimi

Answer 31

Extensor expansion of 5th digit

Question 32

What is the innervation of extensor digiti minimi?

Answer 32

Radial nerve (deep branch) (C7, C8)

Question 33

What are the muscle actions of Extensor Carpi Ulnaris

Answer 33

Extend Wrist

Ulnar Deviation

Active during fist clenching

Question 34

What is the distal attachment of the Extensor Carpi Ulnaris

Answer 34

Base of the 5th metacarpal

Question 35

What is the innervation of Extensor Carpi Ulnaris

Answer 35

Radial Nerve c7 c8

Question 36

What is the distal attachment of Extensor Indicis

Answer 36

Extensor expansion of 2nd digit

Question 37

What is the proximal attachment of Extensor Indicis

Answer 37

Posterior ulna and interosseous
membrane

Question 38

What is the muscle action of Extensor Indicis

Answer 38

Extend the 2nd digit (MCP joint)
May assist to extend the wrist (radiocarpal joint)

Question 39

What is the innervation of Extensor indicis

Answer 39

Radial (PIN) C7 and C8

Question 40

What is the most ventral muscle that the Radial nerve innervates?

Answer 40

Brachioradialis

Question 41

What 3 intrinsic muscles are innervated by 2 nerves?

Answer 41

1. Lumbricals of hand
2. Flexor Pollicus Brevis
3. Flexor Digitorum Profundus