Elbow

Question 1

Elbow Complex

Answer 1

made up of three articulations:
humeroulnar joint
humeroradial joint
proximal radioulnar joint

Question 2

Monteggia Fracture

Answer 2

fracture of the proximal ulna with radial head dislocation, often classified by the direction of radial head dislocation

Question 3

Type 1 Monteggia Fracture

Answer 3

60% of the time

anterior radial head dislocation with palmar angulation

Question 4

Humeroulnar joint

Answer 4

uniaxial hindge between the trochlear notch of the proximal ulna and the trochlea of the humerus
carrying angle: 11-14 in males and 13-16 in females

Question 5

humeroulnar joint open pack position

Answer 5

70 deg of flexion and 10 deg supination

Question 6

humeroulnar joint close pack position

Answer 6

full extension and maximum forearm supination

Question 7

cubital valgus

Answer 7

increased angulation

can be caused by lateral epicondylar fracture

Question 8

cubital varus

Answer 8

decrease in carrying angle
aka gunstock deformity
usually a supracondylar fracture due to extension injury

Question 9

Humeroradial joint

Answer 9

uniaxial hinge between capitellum of humerus and concave head of the radius

Question 10

open pack position of the humeroradial joint

Answer 10

extension and forearm supination

Question 11

close pack position of the humeroradial joint

Answer 11

90 deg elbox flexion and 5 deg supination

Question 12

Proximal radioulnar joint

Answer 12

uniaxial pivot between radial head and radial notch of the ulna
annular ligament forms 80% of the articular surface

Question 13

open pack position of the Proximal radioulnar joint

Answer 13

70 deg flexion and 35 deg forearm supination

Question 14

close pack position of the Proximal radioulnar joint

Answer 14

5 deg forearm spunation

Question 15

Annular ligament

Answer 15

maintains the relationship between the head of teh radius and the humerus and ulna

Question 16

Nursemaids elbow

Answer 16

aka pulled elbow

radial head slippage from under the annular ligament trapping the ligament in the radiohumeral articulation

Question 17

Elbow joint capsule

Answer 17

thin but strong
does not respond well to injury or prolonged immobilization and commonly forms thick scar tissue which may result in flexion contractures of the elbow

Question 18

Medial Collateral Ligament

Answer 18

functionally most important ligament in the elbow for providing stability against valgus stress
three components: 
anterior bundle
transverse bundle
posterior bundle

Question 19

Anterior bundle of the MCL

Answer 19

anterior band is the strongest and stiffest, stabilizes the elbow against valgus stress in 20-120 deg of flexion
posterior band is taut beyond 55 deg of elbow flexion, primary restraint to passive elbow extension, equal co-restraint with the anterior band at terminal elbow flexion, resists valgus stress

Question 20

transverse bundle of the MCL

Answer 20

aka coopers ligament

fibers originate and insert on the ulna and have little role in elbow stability

Question 21

posterior bundle of the MCL

Answer 21

a thickening of the posterior elbow capsule

provides secondary restraint to valgus stress at greater than 90 deg flexion

Question 22

little leaguer’s elbow

Answer 22

avulsion of the medial epicondyle
usually found in child or adolescent and is associated with sports requiring strong throwing motions
overuse injury

Question 23

Lateral collateral ligament of the elbow

Answer 23

consists of annular ligament, fan-like radial collateral ligament, accessory collateral ligament, and lateral ulnar collateral ligament
functions to maintain the ulnohumeral and radiohumeral joints in a reduced position when the elbow is loaded in supination

Question 24

Olecranon bursa

Answer 24

main bursa of the elbow complex, lies posteriorly between the skin and olecranon process

Question 25

Olecranon bursitis

Answer 25

aka miners elbow/ student's elbow | chronic or acute trauma to the tip of the elbow

Question 26

Myositis Ossificans Elbow Flexor

Answer 26

most common sites are brachialis anterior, quad, adductor, and MCL of the knee most occur following any local injury sufficient to cause bruising or frank hemmorhage within a muscle heterotrophic bone formation in the soft tissue

Question 27

Contents of the cubital fossa

Answer 27

``` biceps tendon median nerve brachial artery radial nerve median cubital or intermediate cubital cutaneous vein ```

Question 28

elbow flexion

Answer 28

150 degrees

Question 29

elbow extension

Answer 29

0 degrees

Question 30

forearm supination

Answer 30

80 degrees | at radio-ulnar joint

Question 31

forearm pronation

Answer 31

80 degrees