BIOMECHANICAL COURSE ENT 218 l l Final exam

BIOMECHANICAL COURSE ENT 218 l l Final exam 60% Mid term: 15% Quizzes and assignments: 15% Lab : 10%

BASIC BIOMECHANICS Define the terms biomechanics, static, dynamics, kinematics, and kinetics and explain the ways in which they are related. Identify and describe the reference positions, planes, and axes associated with the human body. Define and appropriately use directional terms and joint movement terminology. Identify and describe the uses of available instrumentation for measuring kinematics quantities.

What is biomechanics? bio mechanics Application of mechanical principles in the study of living organisms

Biomechanics/Mechanics Statics : study of systems in constant motion, (including zero motion) Dynamics : study of systems subject to acceleration

Biomechanics/mechanics • Kinematics: study of the appearance or description of motion • Kinetics: study of the actions of forces

Mechanics Static Kinematics Movement with constant velocity An area of physics that consists of the study of motion and the effect of forces on an object Dynamics Kinetics Force acting on the object at rest and moving with constant velocity Kinematics Movement with acceleration Kinetics Force acting on the object moving with acceleration

KINESIOLOGY Biomechanics Kinematics Linear Angular Position Velocity Acceleration Kinetics Linear Angular Force Torque

KINESIOLOGY The scientific study of human movement. Human movement • Identify discrete phases in an activity • Describe segmental movements in each phases • Identify major muscle contributors to each joint movement Rising from chair • Movements of hip extension • Knee extension • Plantarflexion

BIOMECHANICS The applications of mechanics to human movement Human movement • Describing motion characteristics of human movement using parameters such as speed, direction, acceleration. • Study on how motion is created through application of forces both insides and outside the body. Rising from chair Measure and identify joint forces acting at the hip, knee, and ankle along with the force between the foot and the floor (all of which act together to produce the movement up out of the chair)

BIOMECHANICS RESEARCH Dr. OS (Housh, Housh and Johnson - 2003) Developmental biomechanics Evaluate fundamental movement patterns in performing gross (crawling, walking – involve large muscle group) and fine motor skills (manipulating small objects, transferring object – involve small muscle group).

BIOMECHANICS RESEARCH Occupational Biomechanics Focuses on providing safe and efficient working environment, both indoors and outdoors. l Better Safety equipment – helmets, shin guards, footwear to protect from any work hazards. l Safe and ergonomic working tools to minimize overuse injuries of both upper and lower limbs l Designing of mass public transportation – airplanes, trains, boats and automobiles for safety and efficiency. l Close allied with the science of ergonomics

BIOMECHANICS RESEARCH Rehabilitative Biomechanics Observe movement patterns of individuals who are either injured or/and disabled, provide appropriate interventions which enable injured and disabled person to function as close to, if not normally. Develop exercise equipment, supplementary aids such as walkers, orthotics and even substitution devices such as prostheses for rehabilitation purposes.

BIOMECHANICS RESEARCH Exercise and Sport Biomechanics Describe technique and movement patterns, quantify the contributions of joint actions to technique and in some cases, to predict and evaluate optimal conditions of performance l l l Integrate the use of exercise machines for improving strength, endurance, flexibility and speed. Minimize sport related injuries and enhancing performance Make improvements on equipment such that it is comfortable, easier to use, and provide a safe and effective resistance for improving training and performance.

Qualitative vs Quantitative Analysis Qualitative: pertaining to quality (without the use of numbers) Quantitative: involve numbers Both are important for biomechanical analysis of human motion. Some rely on quantitative, some on qualitative analysis.

ASSIGNMENT In a group of two, write a summary of two activities involving human motion analysis. Identify the following items: 1. What are the problems that encourage the writers to do such research? (10 marks) 2. What are the parameters involve in such analysis? (5 marks) 3. What are the equipments and method used in conducting the experiments? (5 marks) 4. Brief explanation on the results (15 marks) 5. What are things to be considered in the future related to the experiment? (15 marks)

ASSIGNMENT 1 • The assignment should be submitted within a month from the first lecturer. • Mark will be given according to explanation given (easy to understand, figures and other initiatives) • Please use MICROSOFT WORDS to write the assignment. • Any late report will have penalties on the marks.

Chapter 2 Kinematic Concepts for Analyzing Human Motion Identify and describe the reference positions, planes, and axes associated with the human body. Define and appropriately use directional terms and joint movement terminology. Identify and describe the uses of available instrumentation for measuring kinematics quantities.

What is anatomical reference position? Erect standing position with all body parts facing forward. Considered the starting point for all body segment movements

BODY SEGMENT NAMES Up pe Head ra Upper Extremity • AXIAL • Accounting 50% of body weight • Moves slower the other parts of the body APPENDICULAR • The lower and upper extremity • Away from trunk become smaller, • faster and their movement • is difficult to observe rm Forearm Hand NECK TRUNK Leg Foot Lower Extremity Thigh

Directional Terms Superior: closer to the head. Inferior: farther away from the head. Medial: toward the midline of the body. Lateral: away form the midline of the body.

Directional Terms Anterior: toward the front of the body Posterior: toward the back of the body Proximal: closer to the trunk Distal: away from the trunk

Directional Terms Superficial: toward the surface of the body Deep: inside the body away from the surface

Reference Planes Sagittal plane - in which forward and backward movements occur Frontal plane - in which lateral movements occur Transverse plane - in which rotational movements occur

Reference Axes Mediolateral axis - around which rotations in the sagittal plane occur Anteroposterior axis around which rotations in the sagittal plane occur Longitudinal axis around which rotational movements occur

FORM OF MOTION Linear Motion Rectilinear Motion = along a straight line Curvelinear Motion = along a curved line + Angular Motion = rotation around an axis = General Motion = Combination of linear motion and angular motion

Forms of Motion Linear motion: motion along a line Rectilinear motion: (along a straight line) Curvilinear motion: (along a curved line)

GENERAL MOTION General motion: a combination of linear and angular motion (includes most human motion)

THE MOVEMENTS DESCRIPTION The six basic movement descriptors Flexion, extension, Abduction, adduction, Rotation (medial and lateral). Specialized movement descriptors Head and trunk only Lateral flexion Shoulder girdle movement Elevation, depression Protraction and retraction (adduction and abduction in scapula) Upward and downward rotation

THE MOVEMENTS DESCRIPTION Specialized movement descriptors Arm and thigh Horizontal abduction and adduction Forearm Pronation and supination Wrist joint Radial and ulnar flexion Foot Plantar and dorsiflexion Inversion and eversion Pronation and supination

MOVEMENTS IN THE SAGITTAL PLANE Flexion Anteriorly directed sagittal plane rotations of the head, trunk, upper arm, forearm, hand thigh. Posteriorly directed sagittal plane rotation of the lower leg. Bending movement in which the relative angle of the joint between 2 adjacent segements decreases. Extension Return the body to the anatomical position. Straightening movement in which the relative angle of the joint between 2 adjacent segments increases as the joint return to the reference position. Hyperextension

MOVEMENTS IN THE SAGITTAL PLANE Hyperflexion (Hyperextension) – movement that goes beyond the normal range of flexion (extension - movement that goes beyond the anatomical reference position and opposite of flexion)

SAGGITAL PLANE MOVEMENT Dorsiflexion: bringing the top of the foot toward the Tibia, angle between the leg and foot decrease. Plantarflexion: opposite motion of Dorsiflexion, bottom of the foot moves down and the angle between the leg and foot increase. Dorsiflexion Plantar flexion

Movements in the frontal plane • Abduction & adduction – move a body segment away from and closer to the midline of the body, respectively. Abduction Adduction

Lateral flexion l Bending to one side. The term lateral flexion is used to describe motions of the trunk and neck. Elevation & depression l Movement of shoulder girdle in the superior and inferior direction Lateral flexion Elevation Depression

Inversion & eversion l Inward and outward rotation of the sole of the foot, respectively. Radial & ulnar deviation l. Side-to-side movement of the hand at the wrist, toward and away from the thumb, respectively. r e d u c t i o n i n h a n d s t r e n g t h w i t h j u s t 2 5 ° o f m o t i o n f r o Eversion Inversion

Movements in the transverse plane Left & right rotation (head, neck, trunk) Medial (internal) & lateral (external) rotation – toward midline and away from midline, respectively. Medial rotation Lateral rotation

Supination – Outwards or upwards. Frontal Plane Rotation of a body part, usually the hand forearm so that the palm is down. Transverse Plane Rotation of the forearm, outwards and inwards. In the foot (subtalar joint), it is a combination of motions resulting in a position such that the foot is abducted and everted. Pronation – Inwards or downwards. Oppose the supination Pronat Supin ion ation

**Horizontal abduction & adduction Adduction - from lateral to anterior position (also called horizontal flexion) Abduction – from anterior to lateral position (also called horizontal extension) Horizontal adduction Horizontal abduction

Spatial Reference Systems Useful for standardizing descriptions of human motion. Most commonly used is the Cartesian coordinate system. Human body joint centers are labeled with numerical x and y coordinates.

Spatial Reference Systems Y (x, y) = (3, 7) (0, 0) X Cartesian coordinates of the hip

Spatial Reference Systems y x=y=+ x=+ y=+ x (0, 0) x=y=- x=+ y=- Coordinates can be both positive and negative.

TOOLS FOR MEASURING KINEMATIC QUANTITIES Objective: To determine the coordinates of the marked points as a function of time Direct Measurement Techniques Goniometers Special Joint Angle Measuring Systems Accelerometers Indirect Measurement (Imaging) Techniques Cinematography Television Optoelectric technique Others indirect measurement

TOOL FOR KINEMATICS MEASUREMENT OPTICAL SYSTEM Cinematography (movie cameras) Type of film use depend on lighting available, Television The major difference between Cinematography and Television is the frame rate (The number of images that are shown or sent each second) , where the Television has a fixed frame rate (50 or 60 Hz). Television has high enough field rate for most movement, but too low for quantitative analysis of rapid athletic movement. • Standard video camera – reflective marker produces a trailing edge and blurs image when there is a rapid movement. • CCD cameras – eliminates both blurring and skewing • Infrared cameras – reflected infrared lights from the markers is the only lights picked up by the camera.

Optoelectric Techniques optical Subject wear tiny infrared lights on each desired anatomical landmarks. The lights were flashed sequentially, and detected on a special camera. Non Optical techniques Magnetic System – Sensors are linked by cables to a computer. Electromagnetic System – the subjects wear a body suit. Acoustic Systems –Sonar uses reflected sound waves.

Advantages and Disadvantages of Optical Systems Advantages Most systems are not limited to the numbers of markers used. Encumbrance to movement is minimal (lightweigth reflective markers). Inexpensive (VCR and TV cameras). TV and Cine can be replayed for teaching purposes or for qualitative analysis of the total body movement. Disadvantages Most multiple cameras are expensive. Some imaging system cannot be used outdoor.

TUTORIAL FOR NEXT WEEK In a group of 5, write a five minute presentation on the motion capture system. The presentation will be done during the tutorial session. The purpose of the presentation is to identify and describe the type of kinematics measuring equipment that are currently available. Includes: 1. Classification (imaging – Cinematography, Television, Optoelectric technique; Other techniques - Magnetic, electromagnetic, acoustic or any other technique). 2. Advantage and disadvantages of the system (cost, limitation in place, and other factors to be considered)