forearm

Question 1

Does the forearm act independently or with other joints

Answer 1

independently

Question 2

interosseous membrane

Answer 2

transfers force from the radius to the ulna
keeps the bones together

Question 3

what does the radial styloid process do

Answer 3

blocks radial deviation

Question 4

what is the significance of the dorsal radius

Answer 4

it extends down more therefore blocking wrist extension

Question 5

oblique cord

Answer 5

prevents traction of the radius as well as the distal oblique fibers

Question 6

annular ligament

Answer 6

wraps around the head of the radius and is lined with articular cartilage
keeps the bones together and prevents the radius from dislocation

Question 7

quadrate ligament

Answer 7

runs from ulna to the radius and keeps radius on ulna during compressive forces (when bones will separate more)

Question 8

distal radioulnar joint with the carpals and
ligaments

Answer 8

-dorsal capsular ligament
-palmar capsular ligament
-articular disc on ulnar head (ulnar doesn’t articulate with carpals)
-scaphoid facet and lunate facet on radius

Question 9

compression forces on the forearm

Answer 9

cause the radius and ulna to spread
interosseous membrane/quadrate ligament told tension

Question 10

tension/distraction forces on the forearm

Answer 10

oblique cord and annular ligament taut
interosseous membrane on slack

Question 11

what is the closed pack position of the forearm

Answer 11

fully pronated

Question 12

open pack position of the forearm

Answer 12

fully supinated

Question 13

neutral position of the forearm

Answer 13

thumb side of Hand facing up

Question 14

arthrokinematics of supination on proximal and distal radioulnar joints (open chain)

Answer 14

distal: roll and slide happen in the (same) posterior direction
-palmar capsular ligament is taut and dorsal capsular ligament has slack

Proximal: spin occurs laterally

Question 15

arthrokinematics of pronation on proximal and distal radioulnar joints (open chain)

Answer 15

distal: roll and slide occur anterior direction (in the same direction)
-palmar capsular ligament has slack and dorsal capsular ligament is taut

Proximal: spin occurs medially

Question 16

What motion gives compression forces on the humerus

Answer 16

-pronation from the radius due to the angle of pull by the pronator tires

Question 17

arthrokinematics of supination on proximal and distal radioulnar joints (closed chain) ???

Answer 17

Ulna moves on the radius
- ulnar motion can be made up with shoulder IR/ER rotation
-limited pronation can be made up with IR and vice versa

Question 18

prime supinators

Answer 18

supinator
biceps

Question 19

secondary supinators

Answer 19

EPL and extensor indices

Question 20

primary pronators

Answer 20

pronator teres
pronator quadratus

Question 21

secondary pronators

Answer 21

FCR

Question 22

when is the biceps the strongest for supination

Answer 22

when the elbow is at a 90* due to that being its longest moment arm

Question 23

what is stinger supinators or pronators

Answer 23

supinators
-more muscles (4 of them)
-bigger cross sectional area
can generate 25% more torque