interdiction to biomechanics

Question 1

What is Biomechanics?

Answer 1

The application of mechanical laws to living structures, specifically to the locomotor system of the human body

Question 2

Less energy is required when:

Answer 2

There is minimal displacement of the center of mass Each moveable segment functions ideally -The Elements or Determinants of Gait

Question 3

How is this done efficiently?

Answer 3

-Newton’s Laws are applied -Muscles, tendons and ligaments function as levers and pulleys -The Elements or Determinants of Gait

Question 4

A series of movements orchestrated by: name 4

Answer 4

Stable joints Muscle actions Angular momentum Sequential kinematic activity

Question 5

What Creates Joint Stability?

Answer 5

Bones and Joints

Shape of bones

Design of articular cartilage in bones

Ligaments and Joint Capsule

Provide resistance against ground

reactive force

Prevent unwanted movement

Support desired joint position

Neuromuscular activity

Types of muscular contraction

Agonist, antagonist dynamics

Joint proprioception

Question 6

Bones work as

Answer 6

Levers and Shock Absorbers​

Question 7

Bones have ?

Intrinsic strength to resist—

Designed for function( name 3)

Answer 7

——Intrinsic strength to resist external forces or stresses

Shock absorption

—Distribution of external stresses

—Muscle attachments

Question 8

—Joint Stabilizers.

Osseous configuration of bone

Answer 8

—Anterior lip of tibial plateau

—Anterior medial aspect of calcaneus

—Posterior cuboid

Lateral process of talus

Question 9

—Knee Joint Extension

where is it and what does it pervent

Answer 9

—Anterior lip of the medial facet of the tibia

—Prevents over-extension of the knee

Question 10

—Calcaneo-cuboid Joint

what is excrssive pronation inhibited by ?

what does this create?

Answer 10

—Excessive pronation inhibited by the dorsal “overhang” of the calcaneus

—This creates a close-packed position

Question 11

—Articular congruity

type of joint

Answer 11

—Type of joint

—Ball and socket

—Condyloid

—Saddle

—Hinge

Question 12

—Ligaments

Answer 12

—Orientation

—Joints passed

Question 13

—Knee Joint Stability

Answer 13

—Medial and Lateral Collaterals

—Anterior and Posterior Cruciates

Question 14

—Ankle Joint

Answer 14

—Deltoid Collateral – Medial stability

—Lateral stability

Question 15

——Lateral stability-Intracapsular ligaments

Answer 15

—Anterior talofibular ligament

—Posterior talofibular ligament

Question 16

—Lateral stability-—Extracapsular crossing two joints

Answer 16

—Calcaneal fibular ligament

Question 17

Muscles are what type of movers?

Question 18

Joint Stabilizers depend on

Answer 18

—Muscles

—Orientation to joint

—Pennation

—Type of tendinous insertion

Question 19

—Role in joint movement

Answer 19

—Prime mover

—Antagonist

—Synergist

—Stabilizer

Question 20

—Type of contraction

Answer 20

—Isometric

—Isotonic

Question 22

—Architecture

Answer 22

—Parallel

—Pennate

—Type of muscle fibers

Question 23

Muscular Activity and Composition depends on

Answer 23

—Role in joint movement

—Type of contraction

Architecture

—Relation to joint axis

—Shape of tendon

Question 24

Stability
Neuromuscular Contributions

( will break slides up)

Answer 24

—Proprioception – “Sense of Self”

—Conscious – Dorsal Columns

—Unconscious – Cerebellar

—Mediators of Proprioception

—Muscle spindle – monitors muscle length

—Golgi tendon organ – monitors muscle tension

—Pacinian corpuscle - monitors pressure

Question 25

Proprioception

Answer 25

Sense of Self”

Question 26

Conscious

Answer 26

Dorsal Columns

Question 27

Unconscious

Answer 27

Cerebellar

Question 29

—Mediators of Proprioception

Answer 29

—Muscle spindle – monitors muscle length —Golgi tendon organ – monitors muscle tension —Pacinian corpuscle - monitors pressure

Question 30

Locomotion The Act of Walking Two basic requisites

Answer 30

—Continued ground reactive forces —Periodic movement in the direction of progression

Question 31

—Locomotion The Act of Walking Center of mass:

Answer 31

—Should remain in pelvis —The body should NOT tip!!!

Question 32

The Goal

Answer 32

To keep the center of mass within the pelvis

Question 33

To keep the center of mass within the pelvis

Answer 33

—Ideally… —It “hovers” at constant height and minimally changing velocity —Why??? —Decreases the energy required to walk

Question 34

Imaginary Points what are they and —Where is it?

Answer 34

—The Center of Mass —The Center of Gravity —Where is it? —2 inches anterior to the second sacral vertebrae —It follows vertical and horizontal displacement

Question 35

—The Center of Mass

Answer 35

—The point where the distribution of mass is equal in all directions —It does not rely on gravitational pull

Question 36

—The Center of Gravity

Answer 36

—The point in a body where the forces of gravity vanish —This may depend on the vertical orientation of the body —The is the product of mass x gravity

Question 37

—In the anatomical position:

Answer 37

—Anterior to S2 vertebra —At ~ 56% of persons height

Question 38

Balance is dependent upon how will it compensate?

Answer 38

upon maintaining the COG above the feet —Body will compensate by bending and extending * Body leans away from the load * Arm swings away from body

Question 39

Vertical Displacement B in pic

Answer 39

—Up and down movement —Highest point: —Midstance —Lowest point: —Double support —Average displacement: —~ 5 cm

Question 40

Horizontal Displacement A in pic

Answer 40

—Side to side movement —Lateral limit: —Midstance —~ 5 cm displacement

Question 42

The Gait Cycle is composed of? and what phase ?

Answer 42

—Composed of: —Stance Phase —Contact —Foot Strike —Loading response ending with Full Forefoot Load —Midstance —Propulsion —Heel Off —Toe Off —Swing Phase – Acceleration, Midswing, Deceleration

Question 43

**Stance Phase** ## Footnote —Closed kinetic chain – divided into?— decrrible the 2 stances

Answer 43

—Closed kinetic chain – weightbearing​ ## Footnote **—Divided into:** —Contact – foot strike to full forefoot load —Foot is loading – “loading response” —Foot adapting to terrain —Absorbs shock **—Midstanc**e – full forefoot load to heel off —Foot converting to rigid lever **—Propulsion** (Terminal Stance) – heel off to toe off —Forward movement of the limb

Question 44

Stance Phase Contact

Answer 44

getting the foot flat on the ground —Foot strike —Loading response

Question 45

Stance Phase what should happen? When does it end?

Answer 45

—Foot becomes “unlocked” to become a **mobile adaptor** —Controlled flattening results in **shock absorption** —Limb is actively extending at the hip and knee —When does it end? Full forefoot load

Question 46

Stance Phase Midstance-what is it? what do muscles act to convert? which mucles are it?

Answer 46

—Midstance – converting to a rigid lever —Muscles acting to convert from a mobile adaptor to a rigid lever: —Hip and knee extensors —Supinators of the subtalar joint —Plantarflexors of the first ray

Question 47

Stance Phase ## Footnote —Propulsion

Answer 47

**—Pre-swing:** —Heel lift —Toe off Foot off loaded —Muscles working to “shorten” the limb to clear the ground —Hip and knee flexors —Dorsiflexion and inversion of foot and ankle

Question 48

Swing Phase ## Footnote —Open kinetic chain? —Divided into: —I —Extending the limb for contact

Answer 48

—Open kinetic chain – distal segment moves freely —Divided into: 1)—Initial swing – limb is accelerating —2)Mid swing —3)Late or Terminal swing : —-Limb is decelerating —-Extending the limb for contact

Question 49

First Element is

Answer 49

Pelvic Rotation​

Question 50

First Element **Pelvic Rotation** —Rotation about ? —This is\_\_\_\_\_\_\_plane motion —Accomplished with ? —Rotation of ? —Increases with ? —The swing leg rotates ? —Rotation is \_\_\_with \_\_\_\_\_\_\_ what is the Goal:? —This action occurs with:

Answer 50

—Rotation about **vertica**l axis —This is **transverse** plane motion —Accomplished with flexion and extension of the hip —Rotation of ~4° on either side of axis —Increases with speed —The swing leg rotates medially —Rotation is 4° with double support Goal: —Vertical adjustment —The limbs are essentially lengthened without lowering the COM —This action occurs with: —Forward advancement of the swing limb —Preparation for heel strike

Question 51

Second Element **Pelvic List** ## Footnote **what type of movent where?** **—Alternating what movement?** **—Adduction =?** **—Abduction=?** **what type of displacemnt ?** **—There is a 5° dip on what?** **—This reduces what?** **—This action occurs with:**

Answer 51

—Downward movement in the frontal plane —Alternating hip movement —Adduction – stance —Abduction – swing —~ 5° angular displacement —There is a 5° dip on the swinging limb —This reduces the height of the apex of the curve —This action occurs with: —Adduction of the weight bearing limb —Abduction of the swing limb

Question 52

Third Element **Knee Flexion in Stance Phase​** **what type of stance –** **what does stance do?** **—Flexes or extend? until when?** **—Normally ~ what degrees?** **—Moves to ______ with \_\_\_\_\_\_\_\_** **—Then does what?**

Answer 52

—Enters stance – —Close to full extension —Flexes until the foot is flat on the ground —Normally ~ 15 —Moves to extension with full weight bearing —Then… flexion with heel off —Elongates and shortens limb

Question 53

Elements 1, 2 and 3 all do what?

Answer 53

—Decrease vertical displacement of COM —Abrupt displacements still occur —Walking is still a series of arcs – not a smooth curve

Question 54

Fourth and Fifth Element Ankle and Foot Mechanisms – ## Footnote —Two intersecting arcs of rotation what do both do ?

Answer 54

—Two intersecting arcs of rotation **—Heel contact –**rotation of ankle about radius formed by heel **—Heel rise –**Rotation of the forefoot Smoothing out the Pathway!

Question 55

Sixth Element Lateral Displacement of Body what type of displacement how long? —Increased when ? —Decreased when? —Slight genu valgum keeps what?

Answer 55

—Side to side displacement —~4-5 cm with each stride —Increased when feet are further apart —Decreased when feet are closer —Slight genu valgum keeps tibia vertical

Question 56

videos

Answer 56

—https://www.youtube.com/embed/6ObNnCTV6MY — —Introduction to gait cycle —Youtube.com/watch?v=QAnEhz6Eqn4&feature=youtu.be