basic elbow

Question 1

What joints contribute to the movement of the elbow?

Answer 1

1. humeral ulnar
2. humeral radial
3. proximal radial unlar
4. distal radial ulnar

Question 2

What is the open can closed pack position of the elbow?

Answer 2

1. open-90 degree flexion neutral pronation and supination

2. closed full extension

Question 3

How is the humeral ulnar joint classified?

Answer 3

1. diarthrodial/saddle
2. synovial
3. hinge

Question 4

What is the axis of motion of the humeral ulnar joint?

Answer 4

1.it lies slightly oblique and medial about 7-12 degrees from the vertical

Question 5

What is the conjunct rotation at the humeral ulnar joint

Answer 5

the trochlear groove is circumscribed in a spiral so the olecranon will…

1. supinate, ER glide laterally with flexion
2. pronate, IR and glide medially with extension

Question 6

What creates the carrying angle?

Answer 6

1. medial surface of the trochlea is more distal than lateral creating an oblique orientation of the axis
2. the groove of the trochlea is spiraled causing the ulna to project lateral in full extension

Question 7

What impact does the trochlear notch have on the elbow?

Answer 7

1. It dictates the position of the ulna relative to the humerus
2. creates conjunct rotation by the orientation of the trochlear groove
3. creates the carrying angle by the oblique orientation of its horizontal axis

Question 8

What are the three basic shapes of the trochlea?

Answer 8

Type 1 goes from lateral to neutral,
type 2 lateral to lateral position,
type 3 lateral to medial position

Question 9

What is the sagital plane orientation of the trochlea relative to the humerus?

Answer 9

45 degree

Question 10

What are the attachments of the medial collateral ligament of the elbow?

Answer 10

1. extends form medial epicondyle to the coronoid and olecranon process and is a thickening of the joint capsule
2. 3 bands
   - posterior- thickening of the capsule from the medial epicondyle to the posterior medial olecranon
   - anterior- thickening of the anterior capsule with some additional fibers superficial the capsule and provides the primary medial stability.
   - transverse- olecranon to coronoid process

Question 11

What are the bands of the medial collateral ligament and when are they loaded?

Answer 11

• posterior-taut after about 60 degrees of flexion
• anterior- is taut in extension
• transverse

Question 12

What are the most importance static stabilizers of the elbow?

Answer 12

1. anterior band of MCL
2. intact joint surface
3. ulnar part of LCL

Question 13

What are the articulating structures of the radial humeral joint?

Answer 13

1. capitellum of the humerus

2. radial head

Question 14

How is the radial humeral joint classified?

Answer 14

1. diarthrodial
2. synovial
3. hinge
4. modified saddle

Question 15

What is the function of the capitotrochlear groove?

Answer 15

1. guids movement of the radial head as the medial rim of the radius fits in it
2. increases stability of the joint

Question 16

What is the annular ligament of the elbow?

Answer 16

1. strong fibroosseous ring lined with articular cartilage
2. covers 4/5th of the radial head
3. tapered distally creating funnel shape
4. blends with the joint capsule and LCL
5. attaches to the anterior and psotieor aspects of the radial notch

Question 17

What are the attachments of quadrate ligament of the elbow?

Answer 17

attaches the inferior edge of the radial notch to the neck of the radius

Question 18

What is the function of the quadrate ligament?

Answer 18

1. re-enforces the inferior proximal radial ulnar joint capsule
2. maintains radial head in oppostion with the radial notch
3. limits radial head spin with pronation and supination

Question 19

What are the ligaments of the proximal radial ulnar joint?

Answer 19

1. annular
2. quadrate
3. oblique cord
4. innerosseous membrane

Question 20

What are the ligaments of the distal radial ulnar joint?

Answer 20

1. innerosseous membrane
2. articular disc of TFCC
3. fibrous capsule
4. anterior and posterior radial ulnar ligaments as part of the capsule that wrap around the ulnar head to the ulnar notch

Question 21

What are the attachments of the oblique cord?

Answer 21

1. ulna tuberosity

2. inferior radial notch just below biceps tubercle

Question 22

How does the position of the elbow effect the movement of the forearm?

Answer 22

1. elbow extension: ulna is fixed so the radius rotates around it with it axis through the annular ligament
2. elbow flexion-radius spin in the annular ligament while the ulna move medial and anterior

Question 23

How does the cubital tunnel change with elbow flexion and extension?

Answer 23

45% increase from full extension to full flexion

Question 24

What are the attachments of the lateral colateral ligament of the elbow?

Answer 24

1. lateral epicondyle to

2. annular ligament and olecranon process

Question 25

What ligaments help support the proximal radial ulnar joint?

Answer 25

1. annular ligament 2. quadrate ligament 3. oblique cord

Question 26

What type of joint is the distal radial ulnar joint?

Answer 26

1. uni-axial pivot joint | 2. convex ulna and concave radius

Question 27

why does a conjunct rotation occur with pronation and supination?

Answer 27

1. occurs because there are two axis of motion for pronation and supination 2. spine of the radius in the annular ligament and arcuate swing of the distal radius around the ulna 3. they work like hinges on a door and if they don't line up you don't open the door 3. the forearm is like a rectangle with the axis of motion for pro/sup traveling from corner to corner creating an conical like motion

Question 28

What limits supination of the elbow?

Answer 28

1. anterior ligament of the distal radial ulnar joint 2. quadrate ligament of the proximal radial ulnar joint 3. ulnar styloid process contacting radius 4. tednon of ECU 5. pronator tone

Question 29

What is the cubital fossa

Answer 29

area formed by ... 1. line between med and lateral epicondyle 2. pronator teres 3. brachioradialis

Question 30

What is found in the cubital fossa?

Answer 30

1. radial nerve 2. biceps tendon 3. brachial artery

Question 31

What limits elbow flexion and extension, normally?

Answer 31

1. flexion normally limited by by soft tissue apposition of the biceps 2. extension limited by boney contact of the olecranon in the olecranon fossa

Question 32

What type of joint is the proximal radial ulnar?

Answer 32

trochoid joint with one degree of freedom | -functional like a ball bearing

Question 33

What limits pronation?

Answer 33

1. quadrate ligament 2. radial tuberosity dropping in the supinator notch 3. ulna and radius come in contact with each other

Question 34

How does the anatomy of the radius and ulna facilitate greater pronation?

Answer 34

1. the longitudnal axis of the radius shifts laterally during pronation to allow the radial tuberosity to drop in the supinator notch 2. the radius and ulna are slight curved allowing for greater pronation before they contact each other

Question 35

How can normal elbow movement compress the TFCC?

Answer 35

during pronation the radius become functionally shorter | -typing position

Question 36

The distal radial ulnar joint is most stable in what position?

Answer 36

Neutral because the anterior and posterior radial ulnar ligaments are both under tension

Question 37

What is a normal valgus angle of the elbow?

Answer 37

10 degrees for men and 15 degrees for women

Question 38

How is the radial head shaped?

Answer 38

1. tapered and cone like | 2. oval shaped being most pronounced in the pronated position

Question 39

What are the myotomes of the UE?

Answer 39

1. dorsal scapular (C5)- retraction 2. suprascapular (C56) and axillary (C56)- abduction 3. upper and lower subscap (C56)- IR 4. musculocutaneous (C567)- flexion and supination 5. radial (5678)- extension, wrist extension, supination 6. median (C56781)- Flexion with radial devation, MCP flexion, thumb opposition 7. Ulnar (781)- flexion with ulnar devation and 5th digit oppostion