Anatomy + Kinesiology Exam 3

Good Posture

The proper alignment in all positions must be considered for its effect on the body.

*supports function by avoiding excessive stress

Kinetic Chain

- When the body moves, each segment affects the next, creating a chain reaction

- This is because the force generated by one segment is transferred to the next, building on the previous motion

Postural deviation (skeletal malalignment)

Misalignment of body segments. This causes other joints in the kinetic chain to compensate

joint stability

Integrity of a joint when it is placed under a functional load

optimal length-tension relationship

ideal position is where muscle can generate the most tension with the least effort (think door and door hinge)

insufficent length-tension relationship

can lead to muscle imbalance and nerve pathology, pain, joint effusion, poor posture, and repetitive activity of one muscle group

Postural Muscles

- support body against gravity

- usually deep muscles

- become overactivated and tightened or shortened

- prone to trigger points

trigger points

Pathological condition characterized by a small, hypersensitive area located within a muscle

Phasic muscles

- Provide movement to extremities

- Superficial muscles

- High percentage of fast-twitch (Type II) fibers

- Become inhibited and weakened

- Prone to tears and inflammation

Spinal Curves

primary curves develop before birth (anterior curve), and secondary curves after birth

Kyphotic Curve

- Anteriorly concave curves

- Thoracic and sacral spines

Lordotic

- Anteriorly convex curves

- Cervical and lumbar spines

Compensatory Curves

A change in curve in one portion of spinal column may result in compensation in other portions.

Common Types of Compensatory Curves

- Sway back -> increased lumbar lordosis

- Flat back -> decreased lumbar curve

How is the Pelvis the key to spinal curvature?

The neutral pelvis is when the iliac crests are level and the Anterior Superior Iliac Spines (ASISs) are level

Abnormal pelvis rotation

- Neutral pelvis = normal lordotic curve

- Anterior (forward) tilted pelvis = sway back occurs

- Posterior tilted pelvis = flat back occurs

Ways Compensatory Curves Can Develop:

- Working at a computer: increased thoracic kyphosis and cervical lordosis

- Texting: Increased thoracic kyphosis

- Scoliosis: Lateral curve of vertebral column

Scoliosis

- Primary curve: first curve to develop

- Secondary curve: compensatory curve; opposite primary curve

*Curve may be:

a. Functional curve: not a permanent curve

b. Fixed curve: permanent curve

Methods for observing posture

Objective tools:

1. Radiographs

2. Photographs

3. Computer analysis

Clinical tools:

1. Goniometers

2. Flexible rulers

3. Inclinometers

4. Plumb lines

Plumb lines

A string with a weight on the end suspended from above representing a "true" vertical landmark

Common Postural Deviations: Hips

Coxa Vara: Hip deformity, the angle of the femur and shaft are < 120 degrees

Coxa Valga: Hip deformity, the angle of the femur and its shaft are increased > 135 degrees

Common Postural Deviations: Knee

Genu Recurvatum: knee joint bends backward (Hyper-extension)

Genu Valgum: knees bend inward (Knock-kneed)

Genu Varum: knees bend outward (Bow-legged)

Common Postural Deviations: Feet

Pes Planus: flat arch

Pes Cavus: high arch

Leg-Length Discrepancy

- Structural (true)

Actual different in bone length between limbs (Measure ASIS to medial malleolus)

- Functional (apparent)

Attributed to something other than bone length discrepancies (Measure navel to medial malleolus)

Swayback Posture

- Increased lumbar lordosis

- Anterior pelvic tilt

- Hip assuming a slightly flexed position

(Potential causes: tight or shortened hip flexors/back extensors, weak or elongated extensors/abdominals)

Flat Back Posture

Decreased lumbar lordosis and lower thoracic kyphosis

(Potential causes: Shortened or tightened hip extensors, abdominal musculature, weakened/elongated hip flexors, back extensors, Decreased general muscle strength, Poor postural position sense)

Kypholordotic Posture

- Anterior pelvic tilt

- Flexed hip joint

- Increased lumbar lordosis

- Increased thoracic kyphosis

(Tightened or shortened hip flexors or back extensors, weakened or elongated hip extensors or trunk flexors, poor postural position sense)

Forward Shoulder Posture

- Humeral head anterior to line bisecting the body in the frontal plane

- Internal GH rotation

(Potential Causes: Shortened or overdeveloped anterior shoulder girdle muscles, Weakened or elongated scapular stabilizing muscles, Abnormal cervical and thoracic spine alignments, Postural muscle fatigue, Large breast development, Repetitive occupational and sporting positions)

Forward Head Posture

- Flexed lower cervical spine

- Flattening or flexion of mid-cervical spine

- Extended upper cervical spine

(Potential Causes: Wearing of bifocals, poor eyesight and need for classes, Muscle fatigue and weakness, Compensatory mechanism for other postural deviations)

Scapular Winging

- Medial border projects posteriorly

(Potential Causes: Weakness of serratus anterior and middle and posterior trapezius muscles, Secondary trauma to the long thoracic nerve

Long thoracic nerve

innervates serratus anterior

Ambulation

Activity of moving from place to place regardless of method (crawling, wheelchair)

Walking

Upright bipedal ambulation

Gait

Clinical term used when referring to walking

Limb/Leg

Entire lower extremity

Gait Cycle

One complete sequence of movements of one leg during walking

Stride or Stride Length

Interval between the time one foot touches the ground and the same foot touches the ground again

Step Width

Side to side distance when walking

Step or Step Length

Interval between the time one foot touches the floor and the other foot touches the floor.

Cadence

- Number of steps per minute

(Adults average about 107 steps per minute)

Velocity

Distance per unit of time

(adults average 2.5-4 mph)

Stance Leg

Weight-bearing limb during gait cycle

Swing Leg

Non-weight-bearing limb during gait cycle

Foot Angle

Angle of foot relative to line of progression

(Imaginary line from heel to 2nd toe)

Ground Reaction Force (GRF)

- Contact of the foot with the ground creates force yielding:

a. Vertical

b. Anteroposterior (A/P)

c. Mediolateral (M/L) components

Center of Pressure (CoP)

Shows the path of the pressure point under the foot during gait

2 Phases of Gait Cycle

1. Weight-bearing (WB) stance phase (60% of cycle)

2. Non-weight-bearing (NWB) swing phase (40% of cycle)

Weight-bearing (WB) stance phase

Begins on initial contact with the surface and ends when contact is broken. Kinetic energy is absorbed from the ground and transferred up the kinetic chain allowing body to move forward

Consists of:

- Initial Contact

- Loading Response

- Midstance

- Terminal Stance

- Preswing

What part of the foot should the Weight-bearing (WB) stance phase occur on?

i. On the lateral aspect of the heel

ii. Then move forward toward the lateral edge of foot

iii. Finally, toward the undersurface of the great toe

Non-weight-bearing (NWB) swing phase

Begins at the instant the foot leaves the surface and ends just before initial contact. This is the low energy phase

Consists of:

- Initial Swing

- Midswing

- Terminal Swing

Normal gait should consist of

i. Efficient gait

- Minimal side-to-side motion and maximal forward motion

ii. Center of gravity (COG)

- Also called "Center of mass"

- Observed as horizontal and vertical movement of the pelvis

(Path should be a sinusoidal curve)

iii. Comfortable Walking Speed

- Average adult = 1.2 to 1.4 m/s (Roughly around 3 mph) This decreases with age due to decreased strength

6 Determinants of Gait:

1. Lateral Pelvic Shift: pelvis moves side to side to maintain COG

2. Lateral Pelvic Tilt: unsupported side of pelvis falls lower than supported side

3. Pelvic Rotation: one side moves forward at a time, they alternate

4. Knee Flexion: causes limb to shorten during mid swing so you don't trip

5. Interaction of Knee Flexion and Plantarflexion: Coordinated to maintain an appropriate vertical distance from floor to pelvis

Gait during Running

- As velocity increases and periods of stance decrease, right and left swing phases reach a point where they overlap

1. This results in periods when neither foot is in contact with the ground "Float Phase"

2. No period of double limb support

- COM is constrained even more due to horizontal and vertical displacement.

- Vertical GRF increase 2-6 x's body weight

Walking vs. Running COM

When walking:

- Reduced vertical and horizontal displacement of the body's COM occurs

When running:

- Vertical and horizontal displacement of the body's COM is constrained even more

2 types of Gait Analysis

1. Qualitative Assessment

2. Quantitative Assessment

How to Observe (Andy's Rules)

1. Observe entire body

- Overall impression of cadence, balance, characteristics

2. View from all four sides

3. Observe one joint of one LE through entire cycle

- Usually start at foot/ankle

4. Observe trunk, UE, and head also

5. Observe with and without shoes

6. Using a water on person's sole to observe parts of gait cycle

- Or inspect shoe tread ware

Normal Arch Type

Neutral foot alignment

Shoe type: Stability

High Arch Type

Supinator

Shoe type: Cushioned

Flatfoot Type

Pronator

Shoe type: Motion control

Common Gait Deviations: Elderly

- Slower cadence

- Wider BOS

- Barely clear floor during swing

- Increased time in double stance

Common Gait Deviations: Temporary or permanent

- Orthopedic

- Neurological

- Acute or chronic

- Pain

Common Gait Deviations: Glutes

1. Gluteus maximus gait:

- Weak gluteus maximus

- Presents as a quick trunk extension movement at the time of initial contact to create hip extension

2. Gluteus medius gait:

- Also called "Trendelenburg gait"

- Weak gluteus medius

- Increased pelvic tilt to involved side

Common Gait Deviations: Abductor Twist gait

- Weak hip external rotators and abductors

- The foot abruptly abducts

Common Gait Deviations: Muscle Weakness

1. Quadriceps weakness:

- Decreased ability to extend knee or maintain knee extension

- Use of hand on thigh pushing posteriorly to keep knee extended

2. Dorsiflexor weakness:

Causes:

1. Foot slap: sound made at initial contact as forefoot hits ground

2. Steppage gait: greater hip and knee flexion (hip hike) to clear foot during swing

Drop foot

Common nerve pathology that prevents dorsiflexion

Common Gait Deviations: Calcaneal gait

During the stance phase, increased dorsiflexion and knee flexion occur on the affected side, resulting in a decreased step length

Common Gait Deviations: Waddling gait

Commonly observed in individuals with diffuse weakness such as that caused by muscular dystrophies

Common Gait Deviations: Vaulting gait

Unequal leg lengths or unable to flex knee. To compensate, plantar flexion of stance leg so swing leg can clear ground

Common Gait Deviations: Circumduction gait

Unequal leg lengths, Knee unable to flex during swing, During swing LE is abducted and swings out and around

Range of Motion Limitations (Toe-In gait vs Toe-out gait)

Toe-In gait:

- Found in midstance or just after push-off

- Can be cause by: Increased tibial rotation and/or Increased hip rotation

- Puts stress on lateral soft tissues and peroneus longus muscle

Toe-out gait:

- Causes same as Toe-in

- Puts stress on medial and plantar soft tissues

Neurological Causes

Hemiplegia gait: loss of function of one side of the body due to brain injury

Ataxic gait: "Parkinson's gait" Lack of coordinated movement. Movements are jerky and uneven, affecting balance

Scissors gait: Caused by spasticity of hip adductor muscles

Pain Causes: Antalgic gait

a "limp", When gait deviations result from pain

Effect of pain on cycle varies depending on:

1. Cause

2. Location

3. Intensity of pain

Vertebral Column: 5 Regions

Cervical: 7 vertebrae

Thoracic: 12 vertebrae

Lumbar: 5 vertebrae

Sacral: 5 vertebrae

Coccyx: 3 fused vertebrae

(Think meal times)

Atlantooccipital (AO) joint

- C1 and occiput

- Main movement his head nodding ("yes")

Atlantoaxial (AA) joint

- C1-C2

- Main movement is rotation ("no")

Cervical Spine

- C2-C7

- Flexion, extension, rotation, side-bending

Thoracic Spine

- T1-T12

- Flexion, extension, rotation, side-bending

- Movement can be limited by rib cage

Lumbar Spine

- L1-L5

- Flexion, extension, slight side-bending

- No rotation

Vertebral Column: Motions

Movement at each intervertebral joint is small, but the sum of all joints produces significant movement

- Flexion

- Extension

- Rotation

- Lateral (side) bending

Vertebral Column: Bony Landmarks draw this one

know these

- Body

- Vertebral arch

- Vertebral foramen

- Pedicle

- Transverse process

- Spinous process

- Lamina

- Facet

- Intervertebral foramen

Intervertebral Discs

- 23 discs, beginning between C2 and C3

- Shock absorption during transmission of forces through spine

- Loss of water content contributes to loss of height with aging

Components of the Intervertebral Discs

Annulus Fibrosus:

- Outer portion

- Encircles and contains nucleus pulposus

Nucleus Pulposus:

- Gelatinous substance in the center

- High water content (70-80%)

Trunk (Soft Tissue Structures)

Linea Alba:

- Vertical fibrous band in anterior midline

- Extends from xiphoid process to pubic symphysis

Rectus Fascia:

- Sheet-like tendon

- Connects obliques and transverse abdominals muscles to Linea Alba

Sternocleidomastoid

- Bilaterally: head and neck flexion

- Unilaterally: lateral neck flexion to same side; rotation of head to opposite side

Scalenes

- Bilaterally: neck flexion

- Unilaterally: lateral neck flexion to same side

Splenius Capitis

- Bilaterally: head and neck extension

- Unilaterally: lateral flexion and rotation of head to same side

Splenius Cervicus

- Bilaterally: neck extension

- Unilaterally: lateral flexion to same side

External Intercostals

Elevate ribs during inspiration

Internal Intercostals

Depress ribs during expiration

Rectus Abdominis

Trunk flexion

External Oblique

- Bilaterally: trunk flexion

- Unilaterally: trunk lateral flexion and rotation to opposite side

Internal Oblique

- Bilaterally: trunk flexion

- Unilaterally: lateral trunk flexion and rotation to same side

Transverse Abdominis

Compression of abdomen

Accessory muscle of respiration

Erector Spinae Group

All perform either cervical and trunk extension

Thoracic Outlet Syndrome

- A disorder caused by compression of: Brachial plexus, Subclavian artery, Subclavian vein

- Results in various vascular, neurological, or muscular s/s

Compression caused by:

Tightness of Scalenes

Cervical rib & clavicle

Possibly an extra cervical rib

Pec minor and rib cage

Poor posture

Brachial Plexus Pathology

a "burner" or a "stinger"

- Caused by either traction or impingement of brachial plexus

- Pain on opposite side of lateral bending= tension

- Pain on side toward lateral bending = compression)

Erb's point

- 2-3 cm superior to the clavicle

- Represents most superficial passage of brachial plexus

- Pressure here can result in pain and paresthesia radiating into arm

Torticollis

- A condition where the neck muscle become tight

- Causes the head to tilt or turn to one side

- Can be:

1. Congenital -> present at birth

2. Acquired -> develops later in life

Rib Contusions

- Bruise to the ribs

- MOI - A blow to the ribs

Costochondral Separation

- Separation of the rib bone from costo cartilage

- MOI -Direct blow or a twisting + Compressive mechanism