Movement Science - Exam 2

One full gait cycle

starts with heel contact of one foot (0%) and ends with another heel contact of the same/ipsilateral foot (100%)

50% of gait cycle

heel contact of opposite/contralateral foot

Stance phase

60%

foot is on floor (early, middle, late subphases)

Swing phase

40%

leg is swinging forwards

Major determinants of gait result from

minimizing COM movement and minimizing overall energy expenditure

MD of Gait - Stance phase knee flexion

normal = 20 degrees

minimizes vertical movement of COM by keeping body low

MD of Gait - Pelvis list (hip drop)

normal = <1 inch of lateral translation

as foot impacts w/ground - pelvis drops downward on opposite side

minimizes vertical movement of COM

Hip drop and posterior hip rotation are energy efficient movements because they

reduce the movement of COM

MD of Gait - Posterior pelvic rotation

rotation of pelvis posteriorly helps reduce energy expenditure by minimizing the movement of COM

reduces the “braking phase” of gait

MD of Gait - Pronation of the

subtalar joint

MD of Gait - 1st ray dorsiflexion (big toe/1st MTP)

normal = >60 degrees during walking

crucial during toe-off phase of gait

crucial for windlass effect of plantar fascia and subsequent support of foot during weight-bearing activities

MD of Gait - Ankle dorsiflexion

normal = 40 degrees

only need 10-20 degrees during normal gait

What does the talus function as in ankle dorsiflexion during gait

as a frictionless ball bearing (b/c 70% of it is covered with cartilage)

MD of Gait - Gluteal friction

essential for controlling motion at the knee and further down the kinetic chain

• upper fibers - lever arm controlling frontal plane motion

• lower fibers - control sagittal and transverse plane motions

Gait cycle of running

contact, midstance, propulsion

**Extra phase = double float phase

Most of running injuries are a result of

overload or “chronic overuse”

The 1st thing you should look at when assessing a running injury is

the individual’s training logs and their running experience

People w/low arches

pronate more rapidly through larger ranges of motion

exhibit more SOFT TISSUE injuries

People w/high arches

hit the ground harder and pronate through very small ranges

exhibit more BONY injuries

Who has the 1st highest injury prevalence? 2nd?

1st = people with LOW arches

2nd = people with HIGH arches

Can stretching be generalized as a recommendation to reduce injury risk for running injuries

NO! (choose what pre-exercise warm-up is right for the patient)

What impact does strength training have on load capacity, stress, and strain on joints

increases load capacity

reduces stress and strain on joints

**Runners who strength train exhibit reduced injury rates

Neurodynamics

communication btw different parts of the NS and its relationship to the MSK system

**ability of nerves to move freely and independently of other tissues

Intervention of neurodynamics

mobilization of the NS as an approach of physical treatment

Neurodynamic assessment

evaluates the length and mobility of the NS

How do neurodynamic assessments influence pain physiology

via the mechanical properties of neural tissues and non-neural structures surrounding the NS

Role of the nerve in neurodynamics

helps muscle move (motor), transmits sensory feedback, reflex, autonomic functions

Nerve symptoms and what they may be manifested as

symptoms - numbness, tingling, burning, pain

manifested as - muscle weakness, atrophy, headaches

Clinical neurodynamics

clinical application of mechanics and physiology of the NS as they relate to each other and are integrated with MSK system

Neurodynamic test

series of intentionally sequence body movements that produces mechanical and physiological events in the NS according to the movements of the test

Neurogenic pain

pain that is initiated or caused by a primary lesion or dysfunction in the PNS or CNS

Mechanical functions

tension, compression, movement

Positive neurodynamic test

provocation or reproduction of symptoms

Physiologic functions/key components being tested in neurodynamic testing (interrupt the most!)

intraneural blood flow, impulse conduction, axonal transport, inflammation, mechanosensitivity

Innervated tissues

any tissue innervated by the NS (skin, muscle, tendon…)

Three primary mechanical functions that the NS must successfully execute to move normally

withstand tension

slide in its container

be compressible

Effects of tension on intraneural blood flow

8% elongation - flow of venous BF from nerves starts to diminish

15% elongation - all circulation in/out of nerve is obstructed

Effects of compression on intraneural blood flow

nerves that have been previously compromised by compression may be more sensitive to smaller pressure producing neuropathic symptoms

Neurodynamic sequencing

performance of a set of particular component body movements so as to produce specific mechanical events in the NS

Neurodynamic sequencing - greater strain in nerves occurs where

the force is applied 1st and most strongly

Sequence of movements influences the

location of symptoms

Structural differentiation is performed with

ALL neurodynamic tests

Structural differentiation is achieved by

moving the neural structures in the area in question without movement the MSK tissues in the same region

The NS is emphasized in structural differentiation when the relevant neural structures are moved without

moving the adjacent MSK structures

You use structural differentiation to ______ your diagnosis

confirm

Events occur in the following order during a joint movement

taking up of slack early in the range

rapid neural sliding in the mid-range

tension builds in the NS as nerve movement diminishes at end range

ULNT1 tests what nerve and roots

median N

C5-7

ULNT2 (“supination”) tests what nerve and roots

median N

C5-7

ULNT3 (“pronation”) tests what nerve and roots

radial N

C5-T1

ULNT4 (“goggles on”) tests what nerve and roots

ulnar N

C8-T1

LLNT - Straight leg raise tests what nerve and roots

sciatic N

L4-S2

LLNT - Slump test tests what nerve and roots

sciatic N

L4-S3

LLNT - Femoral N stretch test (prone knee bend test) tests what nerve and roots

femoral N

L2-4

Which of the lower limb neurodynamic tests is the most sensitive for L5/S1

slump test

Which of the lower limb neurodynamic tests is one of the most reliable tests for mid-lumbar nerve root impingement

femoral N stretch test

Overt signs

observable and explicit responses during clinical assessments related to the NS

Structural differentiation gives what type of result

neural result

Covert signs

refer to subtle findings that may not cause overt symptoms but can still provide valuable diagnostic information

**doesn’t reproduce pt clinical pain

Sliders (nerve flossing)

produces a sliding movement of neural structures relative to their adjacent tissues

**performed by placing tension (elongating) one end of the nerve and reducing tension (shortening) the other end of the nerve in an alternating pattern

Tensioners

produces an increase in tension in neural structures

relies on natural viscoelasticity of the NS but does not pass the elastic limit

**performed by placing tension (elongating) BOTH ends of the nerve

Muscle imbalances lead to

tissue changes that may result in inappropriate patterns of movement

Muscle imbalances are commonly caused by

sedentary lifestyle

What does overuse or underuse of muscles lead to

overuse - shortening/tightening of tonic muscles

underuse - weakening/inhibition of phasic muscles

Global vs local stabilizers

Global - large, long superficial muscles that span two or more joints

Local - small, short deep muscles that span two or more joints

Global and Local stabilizer roles

stabilize and static proprioceptive feedback

**contraction creates tension to introduce stability

Global vs Local movers

Global - large, long superficial muscles that span two or more joints

Local - small, short deep superficial muscles that span two or more joints

Global and Local mover roles

movement and dynamic proprioceptive feedback

**contraction creates movement within a specific pattern

Three types of neuromuscular phenomena that can lead to muscle imbalances

reciprocal inhibition

synergistic dominance

arthrokinetic inhibition

Reciprocal inhibition

occurs when a tight muscle decreases the neural drive to its functional antagonist

**leads to predictable injury patterns

Synergistic dominance

occurs when synergists and stabilizers take over for a weak or inhibited prime mover

Arthrokinetic inhibition

occurs when a muscle is inhibited by joint dysfunction or the capsule that crosses the joint

What things are necessary to ensure proper activity of skeletal muscles

exposure of the human body to gravity forces

routine stability functions

Deficit locomotor system stability triggers

compensatory mechanism - stabilizing function is overtaken by the mobilizing muscles (decreases flexibility)

Upper Crossed Syndrome - Tight/Overactive

upper traps and levator scapulae

pec major/minor

Upper Crossed Syndrome - Weak/Underactive

deep cervical neck flexors

middle and lower traps

Postural imbalances in Upper Crossed Syndrome

forward head posture

increased cervical lordosis and thoracic kyphosis

elevated and protracted (rounded) shoulder

rotation/abduction and winging of scapulae

Lower Crossed Syndrome - Tight/Overactive

thoracolumbar extensors

hip flexors

Lower Crossed Syndrome - Weak/Underactive

abdominals

gluteal muscles (maximus)

Postural imbalances in Lower Crossed Syndrome

thoracic hyperkyphosis

lumbar hyperlordosis

anterior pelvic tilt

slight hip and knee flexion

Key point in MDT

We don’t FIX patients - we ASSIST patients and TEACH them how to self-manage

Primary goal of MDT

identify if pts are appropriate for mechanical therapy or need referral to another provider

Keys to the successful use of MDT

meticulous assessment

emphasis on educating the pt in self-management

appropriate use of progression of forces

Directional preference

direction of loading that reduces or centralizes symptoms and/or improves function

Centralization

PROCESS in which distal symptoms move proximally and remain improved after loading strategies

Centralizing

DURING the application of the loading strategy distal symptoms are being abolished

Centralized

AFTER the application of the loading strategy all distal symptoms are abolished, and only centralized back pain remains

Peripheralization

symptoms move distally or worsen distally with a given direction

End-range and WHY it matters

the final available range with a distinct barrier

often required for meaningful change

Progression of forces (least to most)

pt generated forces

pt overpressure

clinician overpressure

clinician mobilization techniques

manipulation

Average starting point for most patients

10x every 2-3hrs

Postural syndrome

pain only after sustained end-range posture

normal ROM

minimal change with reps

Classification of Postural Syndrome

intermittent local pain

no movement loss

no effect w/repeated movements

pain produced w/sustained static positioning

Treatment of Postural syndrome

micro-break strategies (30-60sec movement breaks every 20-40min)

Dysfunction syndrome (tissue)

local, consistent end-range pain

range loss in that direction

slow remodeling over weeks

Presentation of Dysfunction syndrome

decreased ROM

pain at end ROM

normal load on shortened tissues leads to symptoms

Treatment of Dysfunction syndrome

repeated end-range loading into the limited direction (load/time)

motto is no pain, no gain!

What is the MC syndrome

Derangement syndrome

Derangement syndrome

variable symptoms

possible distal pain, obstructed range

potential for rapid change with the correct direction

What is the “Great imposter” in Derangement syndrome

onset will go from fully functional to total disability

Presentation of Derangement syndrome

typically decreased ROM or obstruction