Spine Biomechanics midterm

What is the study of forces and their effects?

mechanics

What deals with geometry of the motion of objects (ie. displacement, acceleration, velocity)

Kinematics

Study of relationships between force systems acting on the body and the changes it produces in body motion

Kinetics

Used for solving problems related to structure and function of biological and physiological systems

Biomechanics

AN OBJECT AT REST STAYS AT REST AND AN OBJECT IN MOTION STAYS IN MOTION WITH THE SAME SPEED AND IN THE SAME DIRECTION UNLESS ACTED UPON BY AN UNBALANCED FORCE

Law of inertia ( Newtons first law of motion)

resistance to having its state of motion

changed by application of a force

Inertia

Either at rest or moving with a constant velocity

system in equilibrium

THE ACCELERATION OF AN OBJECT DEPENDS DIRECTLY UPON THE NET FORCE ACTING UPON THE OBJECT, AND INVERSELY UPON THE MASS OF THE OBJECT

Law of Force and Acceleration (Newtons second law of motion)

The observed change in motion is

acceleration

FOREVERYACTION,THEREISANEQUALAND OPPOSITE REACTION

Law of action and reaction (Newtons third Law of motion)

Synarthrosis

immovable joint

ie. Sutures of skull and manubriosternal joint

Amphiarthrosis

slightly movable joint

ie. - IVD and pubic symphysis

Diarthorotic

freely moveable

-and most common joint type

Syndesmosis

bones connected by ligaments

synchondrosis

-bones are bound by hyaline cartialge

-Ex. rib attachment to sternum by costal cartilage

Uniaxial movement

1 plane

elbow or knee joint

biaxial movement

2 plane

metacarpalphalangeal joints

triaxial joint

3 plane

should and hip joints

what makes up bone?

proteins, minerals, vitamins

what is the most common type of lever in the human body?

type 3 lever

ie- biceps

what is the rarest lever in the human body?

type 1 lever

In this type of lever the axis is always between the force and the resistance. This is the most versatile lever because it can be manipulated to serve all four of the functions of a simple machine

1st class lever

In this class lever, the resistance is always closer to the axis of rotation than the force. This means that the force lever arm will always be longer than the resistance moment arm

2nd class lever

What are examples of 2nd class levers

Heel raises

- a = supplied by toes

- R is supplied by COG

-F = is supplied by the calf muscle

Push-up

- a feet

- r is gravity

- F is the ground

in this lever the force is always closer to the axis and favors resistance, speed, and range of motion. If the force is moved a small amount the resistance will move a greater amount in the same amount of time

3rd class lever

What is an example of a 3rd class lever?

bicep curl

- a is supplied by the elbow

- f is suplied by teh muscle force

- R is supplied by the load in hand

What causes creep?

occurs in tissue due to expulsion of water

Creep

is the continued deformation over time when constantly loaded

Relaxation

the corresponding eventual decrease in stress that will occur as fluid is no longer exuded

Hysteresis

energy loss exhibited by viscoelastic materials when they are subjected to loading and unloading cycles

Where in the body is the IVD ratio the greatest?

The cervical spine

Where in the body is the IVD ratio the least?

The thoracic spine

In context to IVD the greater the the ratio the more what?

more spinal segment mobility

Annulus Fibrosus

-Fibrous tissue in concentric laminated bands

-Same direction within band

- opposite in adjacent bands

Overnight

The disk expands resulting in increased resistance to forces

During daytime

fluid exits disc

tension goes down and ROM increases allowing lumbar flexion up to 50%

With age and biomechanical stress the chem nature of disc become more or less fibrous

more fibrous

when disc's become more fibrous they become more or less flexible

less flexible

When does a disc deform more than a health one

when injury occurs

Sagittal plane

divides right and left

z-axis

frontal (coronal) plane

divides anterior and posterior

x-axis

transverse plane

Divides superior -inferior

y axis

Setup for overhead squat

- sholder width stance

- feet facing foward

- arms at 90 degrees holding bar and then press over head

Findings for overhead squat, Patient cannot make it to parallel/ decreased hip hinge

Psoas/quad dominance

Findings for overhead squat, knee valgus stress

Glute med/min weakness.

Findings for overhead squat, feet externally flare out on the way down?

Piriformis

Findings for overhead squat, Patient falls forward or backwards or cannot maintain neutral spine=

core weakness

Findings for overhead squat, Heels come up

ankle mobility/plantar fascitis/ achilles tendonitis

Setup for step down

- Have patient on flat surface or on a 6-inch box

- Have them step down, standing on the affected leg and take their unaffected heel on the ground and return to the starting position.

Findings for step down? medial deviation of the effected knee

Glute med/min (step)

Findings for step down? lateral knee pain on affected side the whole way down

IT band

Findings for step down? posterior lateral knee pain on the affected side upon unlocking the knee

popliteus

Findings for step down? Heel lifts and pain in heel on the affected side is relieved

achilles

Findings for step down? Heel lifts but pain increases on the affected side

plantar fasciitis

Wall angel Setup

-Heel, Butt, Low back, Upper back, Head, against the wall

-Shoulders in 90-degree angle and flat against the wall

Wall angel findings? pain in shoulder when placing the setup actively

external rotators

Wall angel findings? no pain but inability to place shoulder in setup position

internal rotators

Wall angel findings? pain over acromion process when placing shoulder

impingement

Wall angel findings? Scapula not on the wall in setup or wall slide

rotator cuff syndrome/ scapula dysfunction

Wall angel findings? low back not in contact with the wall even after feet are moved foward to allow pelvic tilt

psoas contrature

What are the secondary curvatures in the spine?

cervical and lumbar

Coupled motion for c2-t5

lateral bending to one side will result in rotation to the same side for these segments

Coupled motion for T6-L5

Lateral bending to one side will result in rotation to the opposite side in these segments

When does the cervical curve develop?

prior to birth

What limits extension in the thoracic spine?

spinous processes

What is most limited in the thoracic spine?

extension due to spinous process and articular processes

what is the primary movement in the thoracic spine?

lateral bending with axial rotation

what is the primary movement of the lumbar spine?

Flexion/extension

twice as much flexion compared to extension

When does the secondary lordotic curve of the lumbar form

9-12 months beginning to sit up

What is the major stabilizer of the lumbar spine

quadratus lumborum

what does the pelvic joint do?

Provides support for the trunk, guide movement, and helps to absorb the compressive forces associated with locomotion and weight-bearing

at birth the SI joints are....

undveloved, smooth and flat

after ambulation of the SI joints start they....

begin to take on their adult characteristics

Procedure and indication for respiration

°Visually observe the patients normal, relaxed breathing pattern.

°Manually palpate the Lateral Rib cage from T6-T10

Indicate

- poor posture

- MSK pain

Failure for respiration test?

Clavicles or shoulders elevate

lower ribcage does not widen in the horizontal plane

Failure for respiration (supine) test?

Chest breathing dominates abdominal breathing

abdomen moves IN rather than OUT

Modified Thomas Muscle Length Test Indications

Subacute MSK pain

Modified Thomas Muscle Length Test procedure?

•Patient perching at the edge of the table, bring one knee to the chest

•Slowly lower themselves to the table

•Keep knee close to the chest so that the back remains flat

•Allow the opposite (tested) leg to dangle freely from the table

Modified Thomas Muscle Length Test -°If the thigh is horizontal or above horizontal the

hip flexors are shortened or hyperactive

Modified Thomas Muscle Length Test -If the knee extends beyond 90 degrees,

The rectus femoris is shortened

Modified Thomas Muscle Length Test -If the thigh does not extend below horizontal but the knee does fall at 90 degrees,

Then the iliopsoas is shortened

Modified Thomas Muscle Length Test -If the thigh abducts beyond neutral,

Then the TFL is shortened

Modified Thomas Muscle Length Test - if the thigh adducts beyond neutral,

then the joint adductors are shortened

What are the Indications of Janda's Hip Abduction test?

-Lower extremity pain

- Ankle sprain

- IT band syndrome

- Patello-femoral pain syndrome

- Low back pain

- Hip hiking during gait

- QL trigger points

Janda's Hip Abduction procedure?

-Side lying with lower leg flexed at the hip and knee

- Pelvis should be perpendicular to the table

- slowly raise the leg straight up to the ceiling (done by patient)

Janda's Hip Abduction - initiation of movement, cephalad shift of pelvis indicates...

QL involvement

Janda's Hip Abduction - Hip flexion within the first 40 degrees=

TFL involvement

Janda's Hip Abduction - Hip external rotation =

piriformis involvement

Janda's Hip Abduction pelvic rotation =

Glute Med weakness

Janda's Hip Abduction decreased range of motion in abduction =

adductor tightness

Forward Lung

Procedure

- •Step forward and kneel on the floor with one knee down

-•Then, rise back up to a standing position

Scoring

•Fail if

•Inability to reach the floor with the back knee

•Poor balance

•Subtalar hyperpronation

•Knee valgus

•Trunk flexion

•Knee flexion beyond line of the toes

Squat

Procedure

- stand with feet hip width apart

- arms straight ahead or supported

- Squat down until thighs are nearly parallel to the floor

Fail if

°Decreased squat depth

°Subtalar hyperpronation

°Knee valgus

°Knee flexion beyond line of the toes

±Due to restricted posterior hip tightness

°Lumbar hyperextension

°Lumbar Flexion

Mouth opening

Indication

°TMJ, Headaches, Neck Pain

Procedure

°Instruct the patient to open their mouth fully

Scoring

°Failure if

±Chin protrudes forward

±Decreased range of motion (ROM) (less than 3 knuckles vertical clearance)

±Head extends backwards

Janda's Neck flexion test

Indication

°Neck, Whiplash, or Headache pain

Procedure

°Ask patient to actively raise their head up from the table toward their chest

Scoring

°Failure if

±Chin protrusion

±SCM over activity

Shaking