elbow

Question 1

What are the movements of the elbow?

Answer 1

Flexion, extension, pronation, supination

Question 2

Define VaLgus.

Answer 2

Lateral deviation of a distal segment with respect to proximal segment

Question 3

Define VaRus.

Answer 3

Medial deviation of a distal segment with respect to proximal segment

Question 4

What is the range of motion (ROM) for elbow extension?

Answer 4

0-140°

Question 5

What is the ROM for pronation and supination of the elbow?

Answer 5

0-80-90°

Question 6

What is the ROM for activities of daily living (ADLs) involving the elbow?

Answer 6

30° extension to 130° flexion, 50° pronation and 50° supination

Question 7

What ADL creates the biggest elbow load?

Answer 7

1st Work tasks, 2nd push-ups

Question 8

What does an injury at the cubital tunnel cause?

Answer 8

Laceration or compression of ulnar nerve

Question 9

How is the distal humerus curved?

Answer 9

30° anteriorly, 6° of tilt in frontal plane

Question 10

What are the three elbow joints?

Answer 10

• Humeroulnar
• Humeroradial
• Proximal radioulnar

Question 11

What type of joint is the humeroulnar joint?

Answer 11

Ginglymus (hinge) with 1 degree of freedom

Question 12

What is unique about the humeroulnar joint space?

Answer 12

Asymmetrical joint space with decreased space at olecranon fossa and increased space at trochlear notch

Question 13

What joint contact is greater in elbow flexion?

Answer 13

Greater contact at the humeroradial joint

Question 14

What type of joint is the proximal radioulnar joint?

Answer 14

Trochoid (pivot)

Question 15

What is the role of the interosseous membrane?

Answer 15

Important static longitudinal stabilizer of the forearm, less to rotation

Question 16

What are the characteristics of the center of rotation of the elbow?

Answer 16

• Lateral to medial
• Posterior to anterior
• Superior to inferior

Question 17

What is the carrying angle of the elbow?

Answer 17

10-15° valgus of forearm

Question 18

What are the primary static constraints for elbow stabilization?

Answer 18

• Ulnohumeral articulation
• Anterior bundle of medial collateral ligament
• Lateral collateral ligaments

Question 19

What are the secondary constraints for elbow stabilization?

Answer 19

• Radiocapitellar articulation
• Common origin of the flexors
• Common origin of extensors
• Capsule

Question 20

What stabilizes valgus stress at the elbow?

Answer 20

Radial head and olecranon

Question 21

What injuries occur during pitching?

Answer 21

Compression force laterally, tension on medial collateral ligaments, increased valgus moment

Question 22

How should the arm be positioned during the rehabilitation of MCL?

Answer 22

Arm should be in supination

Question 23

How should the elbow be positioned during the rehabilitation of LCL?

Answer 23

Elbow should be pronated

Question 24

What are the main elbow flexors?

Answer 24

• Biceps brachii
• Brachioradialis
• Brachialis
• Pronator teres

Question 25

What are the main elbow extensors?

Answer 25

* Triceps brachii * Anconeus

Question 26

What causes lateral epicondylitis?

Answer 26

Overuse of ECRB and EDC

Question 27

What are the consequences of medial epicondylitis?

Answer 27

Overuse of flexors, pronators, excess valgus force, excess medial tension

Question 28

What is the strongest angle for elbow flexion?

Answer 28

75-90°

Question 29

What are the wrist movements?

Answer 29

* Extension/flexion * Ulnar deviation/radial deviation * Circumduction

Question 30

What is the dart-throw motion?

Answer 30

Neutral wrist > radial deviation > ulnar deviation

Question 31

Why is the dart-throw motion important?

Answer 31

Less movement of scaphoid and lunate, common path of motion and ADL, safe protected ROM

Question 32

What is the ROM of the wrist for flexion?

Answer 32

80°

Question 33

What is the normal ulnar variance?

Answer 33

< 1mm

Question 34

What happens with negative ulnar variance?

Answer 34

2-5mm instead of <1mm, 95% load via radius, increased risk for lunate

Question 35

What happens with positive ulnar variance?

Answer 35

Smaller than normal ulnar variance, 60% load via radius, increased risk of ligamentous tear

Question 36

What should be avoided under distal radius fracture?

Answer 36

Excessive hand squeezing and forceful ROM if no solid fixation