Lecture 8 - Elbow and Forearm Function

Question 1

the stability of the elbow joint is more dependant on ______ when the elbow is flexed

Answer 1

collateral ligaments

Question 2

parts of the elbow joint

Answer 2

Question 3

normal and excessive carrying angle

Answer 3

Question 4

uses of the interosseous membrane

Answer 4

• > holds the radius and ulna tightly together
• > useful in absorbing and transmitting forces received by the hand (especially when weight bearing on the upper extremity)

Question 5

when doe elbow flexors produce the most force

Answer 5

• > elbow flexor torques produced with the forearm supinated are 20-25% greater than when they are pronated

Question 6

do muscles with an insertion point on the elbow move the elbow

Answer 6

Flexors and extensors have origins at the elbow and move the hand and wrist

Question 7

how to increase the torque of the biceps

Answer 7

combining active elbow flexion with shoulder extension

• > combining shoulder flexion with elbow extension minimizes the rate and amount of shortening required by the long head of the triceps to completely extend the elbow

Question 8

do supinators or pronators produce more force?

Answer 8

as a group, supinators produce 25% greater isometric torque than pronators

Question 9

stability of the elbow can be altered by

Answer 9

Muscle imbalances

• > weak muscles
• > tight structures (consider limiting structures)

Instability

• > ligament laxity
• > injury

Loss of neural control

• > impacting dynamic stability

Question 10

elbow conditions

Answer 10

Lateral epicondylitis (tenis elbow)

• > caused overuse

Elbow instability can cause…

Traumatic dislocation

Excessive strain

Question 11

characteristics of lateral epicondylitis

Answer 11

tendons become inflamed (microtearing or degeneration) usually due to overuse

• > the muscles that insert at the lateral epicondyle: the wrist extensor muscles

Question 12

what causes an elbow dislocation or subluxation (partial dislocation in the body)

Answer 12

they are usually the result of a fall on the outstretched hand (FOOSH)

Question 13

tommy john surgery

Answer 13

reconstruction of the UCL

• > replaced with the tendon of the palmaris longus
• > procedure is common amongst baseball pitchers

Question 14

whats actually happening when you hit your funny bone

Answer 14

you hit the ulnar nerve

• > the UN wraps superficially around the medial epicondyle of the humerus

Question 15

explain the functional movements of bringing food up to your mouth

Answer 15

Question 16

explain the functional movement of lowering arm when you’re eating

Answer 16

Question 17

function of elbow extensors

Answer 17

during shoulder flexion, extending the hand and wrists reduces the rate and amount of shortening needed by the triceps, producing a more optimal movement