Movement Analysis Intro

Core tasks in the Movement analysis framework

• sitting

• Sit to stand

• Standing

• Walk & turn

• Step up & down

• Reach / grasp / manipulate

Components of the movement continuum

• initial conditions

• Preparation

• Initiation

• Execution

• Termination

Initial conditions

• initial conditions for first task performance

• Can be systematically varied in subsequent repetitions

Preparation

Evaluate if performer understood the instructions and task requirements

Initiation, Execution, and termination

Evaluate movement patterns and strategies using observable movement constructs

How does movement analysis relate to outcome measures?

Movement analysis is the qualitative component of how a patient executes an outcome measure, not the outcome measure itself but the assessment of a person’s movement while executing the tasks.

Observable movement constructs

• symmetry

• Speed

• Amplitude

• Alignment

• Postural control

  • verticality

  • stability

• Coordination

  • Smoothness

  • Sequencing

  • Timing

  • Accuracy

• symptom provocation

Symmetry

Agreement of the external kinematics and kinematics of movement (ex: left vs right)

Speed

Rate of change or velocity of segment or body displacement from start to finish of a task

Amplitude

The extent or range of movement used to complete a task

Alignment

Biomechanical relationship of body segments to one another as well as to the base of support and environment, in order to achieve the task

What are the components of postural control?

Verticality and stability

Verticality

Ability to orient the body in relation to the line of gravity

Stability

The ability to control the body’s center of mass in relation to the base of support under quasi-static and dynamic conditions

What are the components of coordination?

• smoothness

• Sequencing

• Timing

• Accuracy

Smoothness

A movement is perceived to be smooth when it happens in a continual fashion without any interruptions in velocity or trajectory

Sequencing

Specific order of motor output required to achieve the intended goal of the action

Timing

The overall temporal structure of movement that includes the relative percentage of time devoted to movement segments, including initiation, execution and termination

Accuracy

The closeness of a measured value to a standard or known value; freedom from error

Symptom provocation

An observation or patient report of symptoms; movement that evokes a particular response

How many times per day does an average adult perform sit-stand?

33-71 times daily

What may adults who stand fewer than 45 times daily need to address?

They may need to increase activity to avoid strength deficits

Personal factors that affect sit to stand mechanics/proficiency?

• age

• Height

• Weight

• Lower limb muscular strength

• Balance activity

• Somatosensory and visual perceptual ability

• Psychological anxiety status

Is it easier to perform sit to stand quickly or slowly?

Quickly; performing STS slowly requires greater strength and is overall higher demand

Task and environmental differences affecting STS

• amount of thigh contact

• Speed

• Trunk movement

• Foot placement

• Type of chair

• Chair height compared to individual height

• Use of armrests

• Compliance or stability of surface

Phases of sit to stand

• flexion momentum

• Momentum transfer

• Extension

• Stabilization

Kinetics- definition

• the branch of biomechanics concerned with what causes a body to move the way it does

• The branch of mechanics dealing with the actions of forces in producing or changing the motion of masses

Kinematics

• the branch of biomechanics concerned with the study of movement from a geometrical point of view

• The science which analyzes motion without reference to force

Flexion momentum: critical events

• initial foot placement 10 cm behind knee

• Momentum generation at trunk

Flexion momentum: muscle activation

• tibialis anterior

• Rectus femoris and erector spinae

• Gluteus Maximus and quadriceps

Momentum transfer: critical events

Continued flexion of the hips with ankle dorsiflexion

Momentum transfer: muscle activation

• gluteus Maximus

• Quadriceps

Extension: critical events

• sequence of lower limb extension (knee, hip, and ankle)

Extension: muscle activation

• gluteus Maximus

• Quadriceps

• Gastroc-soleus

Stabilization: critical event

Ankle strategy

Stabilization: muscle activation

• gastroc-soleus

• Tibialis anterior

Outcome measures incorporating STS

• 5 time sit to stand (5xSTS)

• 30 second sit to stand (30sSTS)

• Timed up & go (TUG)

5xSTS

• time how long it takes to STS five times with arms crossed

• 17in chair height

Age norms for 5xSTS

• 60-69 years: less than 11.4 sec

• 70-79 years: less than 12.6 sec

• 80-89 yers: less than 14.8 sec

5xSTS tested in what populations

• Cerebral palsy

• COPD

• Healthy elderly

• Knee OA

• low back pain

• MS

• Parkinson Disease

• peripheral artery disease

• Renal transplant

• Rheumatoid arthritis

• Stroke

• TKA

• Vestibular disorders