General Biomechanical Principles

Question 1

2nd Class Lever

Answer 1

2 Forces acting on the same side of the joint.
The resistance force sits between the effort force and the ankle.
Ex: Toe raises

Question 2

3rd class lever

Answer 2

2 Forces on the same side of the axis
The effort force sits between the axis and the resistance force
Most common type in the body
Ex: Elbow flexion

Question 3

Atlantooccipital joint osteokinematics

Answer 3

Convex on concave

Move in opposite directions

Question 4

C2 and below osteokinematics

Answer 4

Concave on convex

Move in the same direction

Question 5

Distal radioulnar osteokinematics

Answer 5

Concave on convex

Same direction

Question 6

Proximal radioulnar osteokinematics

Answer 6

Convex on concave

Opposite directions

Question 7

Capitate, scaphoid, lunate, triquetrum osteokinematics

Answer 7

Convex on concave

Opposite directions

Question 8

Trapezoid osteokinematics

Answer 8

Concave on convex

Same direction

Question 9

Humeroradial osteokinematics

Answer 9

Concave on Convex

Same direction

Question 10

Humeroulnar osteokinematics

Answer 10

Concave on convex

Same direction

Question 11

Sternoclavicular joint osteokinematics

• Elevation and Depression
• Protraction and retraction

Answer 11

Elevation and depression
- Convex on concave
Protraction and retraction
- Concave on convex

Question 12

AC joint osteokinematics

Answer 12

Concave on convex

Same directions

Question 13

Subtalar joint osteokinematics

• Navicular and cuneiform
• Inversion and eversion; cuboid and calcaneus

Answer 13

Navicular and cuneiform- Concave on convex

Inversion and eversion; cuboid and calcaneus- convex on concave

Question 14

Talocrural joint osteokinematics

Answer 14

Convex on concave

Question 15

Tibiofibular joint osteokinematics

Answer 15

Concave on convex

- fibula moving on tibia

Question 16

Vertebrae resting position

Answer 16

Midway between flexion and extension

Question 17

Vertebrae close packed position

Answer 17

Maximal extension

Question 18

TMJ resting position

Answer 18

Slightly open

Question 19

TMJ close packed position

Answer 19

Max retrusion (mouth closed with teeth clenched)
Max anterior (mouth fully open)

Question 20

SCJ resting position

Answer 20

Arm resting by side

Question 21

SCJ close packed position

Answer 21

Arm maximally elevated

Question 22

ACJ resting position

Answer 22

Arm resting by side

Question 23

ACJ close packed position

Answer 23

Arm abducted to 90 degrees

Question 24

GHJ open packed position

Answer 24

55-70 deg abduction
30 deg horizontal adduction
Neutral rotation

Question 25

GHJ closed packed position

Answer 25

Full abduction and ER

Question 26

Humeroulnar joint open packed position

Answer 26

70 deg flexion | 10 deg supination

Question 27

Humeroulnar Joint closed packed position

Answer 27

Full extension and full supination

Question 28

Humeroradial joint open packed

Answer 28

Full extension and full supination

Question 29

Humeroradial joint closed packed

Answer 29

90 deg flexion | 5 deg supination

Question 30

Proximal radioulnar joint open packed

Answer 30

70 deg flexion | 35 deg supination

Question 31

Proximal radioulnar joint closed packed

Answer 31

5 deg supination | Full extension

Question 32

Distal radioulnar joint open packed

Answer 32

10 deg supination

Question 33

Distal radioulnar joint closed packed

Answer 33

5 deg supination

Question 34

Radio/ulnocarpal joint open packed

Answer 34

Neutral with slight ulnar deviation

Question 35

Radio/ulnocarpal joint closed packed

Answer 35

Full extension and radial deviation

Question 36

Mid carpal joint open and closed packed

Answer 36

Open: neutral with slight flexion and ulnar deviation Closed: full extension

Question 37

CMC 2-5 open and closed packed

Answer 37

Open: midway between flexion and extension Closed: full opposition

Question 38

Trapeziometacarpal joint open and close packed

Answer 38

Open: midway between flexion/extension and abd/add Closed: full opposition

Question 39

MCP joint open and closed packed

Answer 39

Open: 1st MCP slight flexion, 2-5 slight flexion with ulnar deviation Closed: 1st MCP full extension, 2-5 full flexion

Question 40

IP joint open and closed packed positions

Answer 40

Open - PIP 10 deg flexion -DIP 30 deg flexion Closed: full extension

Question 41

Hip open packed position

Answer 41

30 deg flexion 30 deg abduction Slight ER

Question 42

Hip closed packed position

Answer 42

Ligamentous: full extension, abduction, IR Bony: 90 deg flexion, slight abd, slight ER

Question 43

Knee open packed position

Answer 43

25 deg flexion

Question 44

Knee closed packed

Answer 44

Full extension and ER

Question 45

1st Class Lever

Answer 45

2 forces applied on either side of the axis The effort is the force that applies the movement The resistance is the force that opposes the movement Ex: Triceps contraction on the elbow joint