Biomechanics of the Shoulder

Question 1

Biomechanics

What type of joint shape is the Sternoclavicular Joint?

Shoulder

Answer 1

Saddle

Question 2

Biomechanics

The medial end of the clavical is (convex or concave) in the frontal plane and (convex or concave) in the transverse plane.

Shoulder

Answer 2

Convex
Concave

Question 3

Biomechanics

Identify the motions that occur at the Steroclavicular Joint and in which plane they occur.

Shoulder

Answer 3

1) Elevation and depression in frontal plane
2) Protraction and retraction in horizontal plane
3) Posterior clavicular rotation in sagittal plane

Question 4

Biomechanics

During elevation of the clavicle there is a(n) ____ roll and a ____ a(n) glide at the sternoclavicular joint.

Shoulder

Answer 4

Superior
Inferior

Question 5

Biomechanics

During retraction of the clavicle there is a(n) ____ roll and a ____ a(n) glide at the sternoclavicular joint.

Shoulder

Answer 5

Posterior
Posterior

Question 6

Biomechanics

What type of joint shape is the Acromioclavicular Joint?

Shoulder

Answer 6

Planar

Question 7

Biomechanics

What type of joint shape is the Glenohumeral Joint Joint?

Shoulder

Answer 7

Ball-and-Socket

Question 8

Biomechanics

In what direction is glenohumeral joint instability most common?

Shoulder

Answer 8

Anteriorly or Inferiorly

Question 9

Biomechanics

What three structures occupy the Subacromial Space?

Shoulder

Answer 9

Supraspinatus Tendon
Biceps Tendon
Subacromial Bursa

Question 10

Biomechanics

What are the four major ligaments of the glenohumeral joint capsule?

Shoulder

Answer 10

Superior, Middle, Inferior Glenohumeral Ligaments and the Coracohumeral Ligament

Question 11

Biomechanics

During glenohumeral abduction, which way does the joint roll and glide?

Shoulder

Answer 11

Roll Superiorly
Glide Inferiorly

Question 12

Biomechanics

During the full 180 degrees of shoulder abduction, ____ degrees is attributed to the scapulothoracic joint’s upward rotation whereas ____ degrees is attributed to glenohumeral movement.

Shoulder

Answer 12

60, 120

Question 13

Biomechanics

What are the three primary upward rotators of the scapulothoracic joint?

Shoulder

Answer 13

Upper Trapezius
Lower Trapezius
Serratus Anterior

Question 14

Biomechanics

What three motions are required at the scapulothoracic joint during arm elevation?

Shoulder

Answer 14

Uppward Rotation
External Rotation
Posterior Tilt

Question 15

Biomechanics

What does having a SICK Scapula entail?

Shoulder

Answer 15

Scapular Malpositioning
Inferior Angle Prominence
Coracoid Tenderness
Kinetic Abnormalities

Question 16

Biomechanics

Serratus anterior weakness causes issues with which scapular motions?

Shoulder

Answer 16

Protraction, Upward Rotation, Posterior Tilt, External Rotation

Question 17

Biomechanics

When do the middle deltoid and supraspinatus muscles reach their maximum level during elevation?

Shoulder

Answer 17

Near 90° of abduction

Question 18

Biomechanics

Which four muscles socket the humerus and provide stability during shoulder motions?

Shoulder

Answer 18

1. Subscapularis
2. Supraspinatus
3. Infraspinatus
4. Teres Minor

Question 19

Biomechanics

Is glenohumeral internal or external rotation stronger? Which muscles support each movement?

Shoulder

Answer 19

Internal > External
Internal: Subscapularis, Supraspinatus, Pectoralis Major, Latissimus Dorsi, Teres Major, Anterior Deltoid
External: Infraspinatus, Teres Minor, Posterior Deltoid

Question 20

Biomechanics

Which two postural elements increase the subacromial space?

Shoulder

Answer 20

Thoracic Extension and Posterior Scapular Tilt

Question 21

Biomechanics

Shoulder

Question 22

Biomechanics

Shoulder

Question 23

Biomechanics

Shoulder

Question 24

Biomechanics

Shoulder