Basic Biomechanics

Question 1

Study of the movement of one articular surface on another without regard to the movement of the bone or the forces producing the movement

Answer 1

Arthrokinematics

Question 2

In the periphery, movement is named after the direction of motion of the _______ bone

Answer 2

distal

Question 3

In the spine, the movement is named by motion of the _______ bone

Answer 3

superior

Question 4

Study of the forces that produce a movement at a joint – traction, distraction, shear

Answer 4

Arthrokinetics

Question 5

Study of the motion of objects

Answer 5

Kinematics

Question 6

Study and measurement of motion of a bone in space

Study of movement of a bone around it’s mechanical axis without consideration to the motion occurring at the joint surface or the forces producing the movement

Answer 6

Osteokinematics

Question 7

Osteokinematics consists of:

Answer 7

Osteokinematic rotation (spin and swing)
Translation

Question 8

• The number of planes through which a bone can be voluntarily moved actively
• There are potentially three dimensions through which a bone can be moved about a joint

Answer 8

Degrees of motion

Question 9

• A line of reference for osteokinematic motion

- A line passing through the bone perpendicular to the joint surface

Answer 9

Mechanical Axis

Question 10

• Point where all net forces on the bone are zero
• Bone moves around this point
• Perpendicular to the plane of motion

Answer 10

Axis of movement

Question 11

Tipping of the concave surface that occurs at the end of motion
Always occurs in the same direction as the glide (slide)

Answer 11

Rock

Question 12

A rotary movement of one bone rolling on another
Tipping of the convex surface that occurs at the end of motion
Always occurs in the opposite direction to the glide (slide)

Answer 12

Roll

Question 13

One bone spinning on another
Produced by a pure twisting action
Rarely occurs alone in joints but in combination with rolling and sliding

Answer 13

Spin

• The non-linear motion that occurs either at the joint surface (arthrokinematic spin) or around the mechanical axis of the bone (osteokinematic spin)

Question 14

Motion of a bone that is produced by a sliding action within a joint

Answer 14

Swing

• The linear motion that either occurs at the joint surface (arthrokinematic swing) or in the plane of the mechanical axis of the bone (osteokinematic swing)

Question 15

Shortest distance between two points
Swing with no accompanying spin
Bone moves in one plane and in joints that have at least two degrees of freedom Ex. Abduction/adduction and external/internal rotation of the humerus and femur
Swing can occur without the bones taking a curved path
Is functionally abnormal and the exception rather than the rule

Answer 15

Pure (Cardinal) Swing

Question 16

Is accompanied by spin (conjunct rotation)
Composite or impure arthrokinematic or osteokinematic swing that describes an arc
The bone does not stay in one place
Movement of a point on the mechanical axis from A to B follows a line other than the shortest one (arc)
Ex. flexion and extension at index MCP joint can rotate medially or laterally in mid-ranges; The rotation is undone at extreme ranges

Answer 16

Impure (Arcuate) Swing

Question 17

All particles in the body at a given time have the same direction of motion relative to a fixed point
There is no center of rotation as the bone moves along a plane instead of through it

Answer 17

Translation

Question 18

The number of independent axes that a bone can move around

Axes are perpendicular to each other

Answer 18

Degrees of Freedom

Question 19

In joints with one degree of freedom, movement of the bone is limited to motion about a _____ axis and movement of a bone is produced by a ______ action within a joint

Answer 19

single

sliding

Question 20

Two degrees of freedom either has a _____ and ______ or two distinct ______
The axes must be ______ to each other Ex. MCP joints, knee

Answer 20

spin and swing or two distinct swings

perpendicular to each other

Question 21

Three degrees of freedom has a ______ and two distinct _____

Swings must be _______ Ex. Shoulder, hip

Answer 21

spin and two distinct swings

must be cardinal

Question 22

Adjunct rotation is rotation which accompanies a _______
Can also be performed independently about its own ______
Can be voluntarily _____ or ______
Is a separate _________
May only occur with a joint with more than _______ Ex. specific rotator muscles around the hip and shoulder

Answer 22

swing
axis
done or undone
degree of freedom
1 degree of freedom

Question 23

A pattern of limitation of motion for a given joint due to inflammation is referred to as a

Answer 23

capsular pattern

Question 24

Movement composed of a spin that is combined with a conjunct rotation

Answer 24

Composite movement

Question 25

Composite movement is important in achieving _____ packing of joints

Answer 25

close

Question 26

Composite movement must have a component of _______

Answer 26

rotation

Question 27

Composite movement occurs during ____________

Answer 27

most functional movements

Question 28

Rotation of bone and associated structures that occurs in series in the same direction as that of an adjacent bone

Answer 28

Congruent rotation

Question 29

In congruent rotation, rotation does not need to be at the same _____

Answer 29

rate

Question 30

Congruent rotation is a mechanism to prevent _______

Answer 30

torsion

Question 31

Movement occurring as a result of the shape of the joint surfaces and effect of the ligaments rather than muscular effort

Answer 31

Conjunct rotation

Question 32

In conjunct rotation, as the ligament tightens it brings the two joint surfaces ______ together

Answer 32

closer together (towards closed pack position)

Question 33

Conjunct rotation must occur in joints with _______

Answer 33

one degree of freedom

Question 34

Conjunct rotation is a rotation (spin) which must accompany an _______ swing

Answer 34

impure

Question 35

Conjunct rotation is characteristic of movements at both ______ joints and the majority of _______ joints Ex. knee extension with lateral rotation

Answer 35

sellar joints and ovoid joints

Question 36

Consequential movement

Answer 36

Conjunct rotation occurring as a result of a succession of movements

Question 37

Movement that consistently occurs with another that is not a result of voluntary effort

Answer 37

Coupled movement

Question 38

Every diadochal movement contains a _______ (_______) movement

Answer 38

consequential (conjunct)

Question 39

A closed diadochal movement brings the bone _____ from then back to its original position but not necessarily back to its original _______

Answer 39

away | posture

Question 40

An open diadochal movement does not return the bone to its ______

Answer 40

original position

Question 41

Diadochal movement occurs during the

Answer 41

2nd swing

Question 42

Diadochal movement can be undone by performing ________ rotation in the opposite sense during the second swing

Answer 42

adjunct

Question 43

The most common movement of a bone that brings it towards, and away from, the close pack position of the joint

Answer 43

Habitual movements

Question 44

Habitual movements are always _______ swings (swing and spin)

Answer 44

arcuate swings

Question 45

In habitual movements, the swing element ______ the joint structures as it comes toward the close packed position

Answer 45

tightens

Question 46

In habitual movements, the spin element tautens these elements by producing a ___________ to the structure

Answer 46

spiral twist

Question 47

Rotation of bone and associated structures that does not occur in series in the same direction as that of an adjacent bone

Answer 47

Incongruent rotation

Question 48

Incongruent rotation goes against the _________ pattern of movement

Answer 48

habitual

Question 49

Fractures of long bones are susceptible to _________ rotations Ex. If the radius fractures below the level of the supinator muscle, the upper fragment is pulled into supination while the lower fragment is pulled into pronation by pronator quadratus

Answer 49

incongruent

Question 50

Pattern of motion described by the total range of motion undergone during all swings of the mechanical axis of the bone

Answer 50

Ovoid of motion

Question 51

Syndesmosis | Has an interosseus ligament Ex. inferior tibiofibular ligament

Answer 51

Fibrous Joints

Question 52

Syncondrosis Has an articular disc Symphysis: fibrocartilage Synotosis: has bony structures

Answer 52

Cartilaginous Joints

Question 53

Articular surface predominantly hyaline cartilage, sometimes fibrocartilage Consists of fibrous capsule, synovial membrane, synovial fluid

Answer 53

Synovial Joints

Question 54

One pair of articulating surfaces | Most common: One surface convex, one surface concave Ex. hip joints, glenohumeral joint

Answer 54

Simple Synovial Joint

Question 55

More than one articulating pair in a single capsule Neither will articulate with the surface which belongs to the other Ex. Radio-carpal joint, ulno-menisco-carpal joint

Answer 55

Compound Synovial Joints

Question 56

Has an articular disc Ex. sternoclavicular joint, TMJ

Answer 56

Complex Synovial Joints

Question 57

Concave or convex in all planes Degree of curvature will vary from point to point Egg shaped rather than spherical

Answer 57

Ovoid

Question 58

Shape is spherical Allows 3 degrees of freedom Ex. Glenohumeral joint, Hip Joint

Answer 58

Unmodified Ovoid

Question 59

Degree of curvature is more marked in one plane than the other Allows 2 degrees of freedom Ex. MCP, radiocarpal joints

Answer 59

Modified Ovoid

Question 60

Saddle shape Predominantly concave in one plane and convex at right angles to this Tends to be stable and efficient -- requires fewer ligaments as the surface is more congruent

Answer 60

Sellar

Question 61

Joint surfaces are purely concave in one plane and purely convex in the other Joint surfaces are perpendicular to each other Allows 2 degrees of freedom -- Ex. 1st CMC joint

Answer 61

Unmodified Sellar

Question 62

The joint surfaces have both a concave and a convex portion in the same plane Joint surfaces are not perpendicular to each other Allows 1 degree of freedom -- Ex. calcaneocuboid joint

Answer 62

Modified Sellar

Question 63

Movements occurring in joints

Answer 63

Spin Slide Roll

Question 64

Simultaneous sliding and rolling movements of articular surfaces increase the ____________ at a joint and allows maximal ROM with minimal articular surface area

Answer 64

effective range of motion

Question 65

Spin is independent Slide occurs in the same direction as the bone is moving Roll always accompanies slide except at the beginning and end of movement Slide is the most important movement Ex. MCP joint

Answer 65

Concave Ovoid Surface

Question 66

Spin is independent Convex surface rolls along the concave surface Rolls in the same direction as the bone is moving Slide occurs in accompaniment with the roll Occurs in the opposite direction to the moving bone in order to increase movement with smaller joint surfaces

Answer 66

Convex Ovoid Surface

Question 67

Movement within a joint and surrounding soft tissues that is requires for normal ROM but is not performed voluntarily Is reproduced passively Most amount of movement is available from the resting position

Answer 67

Accessory movements

Question 68

When mobilizing a concave on convex surface, the glide is in the _____ direction as the desired movement

Answer 68

same

Question 69

When mobilizing a convex on a concave surface the glide is in the _______ direction to the desired movement

Answer 69

opposite

Question 70

Articular surfaces are maximally congruent The capsule and most of the ligaments are taut The joint surfaces cannot be separated

Answer 70

Close pack position

Question 71

Bone fracture is more likely in this position

Answer 71

Close pack position

Question 72

Combination of swing and spin "screw home" the joints Ex. the knee Most stable joint position Position used to test ligament stability

Answer 72

close pack position

Question 73

Biomechanically efficient position - inability to achieve closed pack position will result in muscle overuse and potential proximal/distal adaptations

Answer 73

Close pack position

Question 74

The close pack position is important for joint lubrication known as ______

Answer 74

weeping

Question 75

Can't mobilize or manipulate in the position

Answer 75

Close pack position

Question 76

Can use to lock joint above or below to obtain specificity

Answer 76

Close pack position

Question 77

Should not rest or splint in this position

Answer 77

Close pack position

Question 78

Any position of the joint that is not close pack | Ligaments and capsule are slack and articular surfaces are not congruent

Answer 78

Loose pack position

Question 79

Position where joint distraction is available | Easy to mobilize in this position

Answer 79

Loose pack position

Question 80

Resting position for inflamed joints | Splinting and casting position

Answer 80

Loose pack position

Question 81

Most distraction of joint surfaces is available | Greatest potential joint space

Answer 81

Rest position

Question 82

Can mobilize in this position Use as a resting position for inflamed joints Position for splinting and casting

Answer 82

Loose pack position | Rest position