PTY1016 Foundation of Physiotherapy: Movement PDF

PTY1016 Foundation of Physiotherapy: Movement Movements This Photo by Unknown Author is licensed under CC BY Alan Wong, PhD [email protected] References Dutton, M. (2020). Dutton’s introduction to physical therapy and pat...

PTY1016 Foundation of Physiotherapy: Movement Movements This Photo by Unknown Author is licensed under CC BY Alan Wong, PhD [email protected] References Dutton, M. (2020). Dutton’s introduction to physical therapy and patient skills (Second edition.). McGraw Hill. Chapter 4: https://accessphysiotherapy.mhmedical.com/content.aspx?bookid=2976&sectionid=250229 067 Houglum, P. A., & Bertoti, D. B. (2012). Brunnstrom's Clinical Kinesiology. (6th ed.). Philadelphia: F. A. Davis Company, chapters 1 & 2. Oatis, C. A. (2016). Kinesiology: The Mechanics and Pathomechanics of Human Movement. (3rd ed.). New York: Wolters Kluwer, Part I (Biomechanical Principles). Norkin, Cynthia C. Levangie, Pamela K (2011) Joint Structure and Function A Comprehensive Analysis. New York, F. A. Davis Company, chapters 1 & 2. Donald A. Neumann (2017). Kinesiology of the Musculoskeletal System. Foundation for Rehabilitation. (3rd ed). NY: Mosby, Elsevier, chapters 1, 2, 4 Topics to be covered Movement Continuum Theory Anatomy and Biomechanics Underlying Movements Describing Movements – Planes of Movements Types of Movements Active vs Passive Movements Concepts Related to Muscle Strength Summary Topics to be covered Movement Continuum Theory Anatomy and Biomechanics Underlying Movements Describing Movements – Planes of Movements Types of Movements Active vs Passive Movements Concepts Related to Muscle Strength Summary Movement Continuum Theory (Cott et al, 1995) General Principles I Movement is essential to human life. II Movement occurs on a continuum from the microscopic level to the level of the individual in society. III Movement levels on the continuum are influenced by physical, psychological, social and environmental factors. Physical Therapy Principles IV Movement levels on the continuum are interdependent. V At each level on the continuum there is a maximum achievable movement potential (MAMP) which is influenced by the MAMP at other levels on the continuum and physical, social, psychological and environmental factors. VI Within the limits set by the MAMP, each human being has a preferred movement capability (PMC) and a current movement capability (CMC) which in usual circumstances are the same. VII Pathological and developmental factors have the potential to change the MAMP and/or to create a differential between the PMC and the CMC. VIII The focus of Physical Therapy is to minimize the potential and/or existing PMC/CMC differential. IX The practice of Physical Therapy involves therapeutic movement, modalities, therapeutic use of self, education, and technology and environmental modifications. Cott, C., Finch, E., Gasner, D., Yoshida, K., Thomas, S., & Verrier, M. (1995). The movement continuum theory of physical therapy. Physiotherapy Canada, 47(2), 87-96. 6 Movement Dimensions Allen, D. D. (2007). Proposing 6 dimensions within the construct of movement in the Movement Continuum Theory. Physical therapy, 87(7), 888-898. This Photo by Unknown Author is licensed under CC BY-SA-NC 6 Dimensions aligned to pathophysiology Allen, D. D. (2007). Proposing 6 dimensions within the construct of movement in the Movement Continuum Theory. Physical therapy, 87(7), 888-898. Topics to be covered Movement Continuum Theory Anatomy and Biomechanics Underlying Movements Describing Movements – Planes of Movements Types of Movements Active vs Passive Movements Concepts Related to Muscle Strength Summary Normal human movements Require an integration of all body systems. Physical activities and movements require a control of intake and expenditures of energy; this means a system for food ingestion, another to transform it into nutrients for normal cell metabolism, another to distribute it, another to transform it into energy, another to control the processes involved, etc. Impairment of one system may impact on human movement, however, extent of impact may differ, e.g. muscular system vs urinary system. Human movement studies would need understanding of other systems, besides skeletal, muscular, nervous and cardiovascular systems. Balderas, D., & Rojas, M. (2016). Human Movement Control. In Automation and Control Trends. IntechOpen. https://www.intechopen.com/chapters/51207 https://reverehealth.com/live-better/how-body-systems-connected/ Image source: https://store.prod.carolina.com/images/teacher-resources/infographics/infographic-Body-Systems-overall.jpg Topics to be covered Movement Continuum Theory Anatomy and Biomechanics Underlying Movements Describing Movements – Planes of Movements Types of Movements Active vs Passive Movements Concepts Related to Muscle Strength Summary Key Concepts Kinematics – types, directions and quantity of movement Osteokinematics Arthrokinematics Kinetics – forces produce or resist movement Planes and axes of movements Cardinal planes Coronal/frontal (XY) Sagittal (YZ) Horizontal/transverse (XZ) What is the anatomical position? Houglum, P. A., & Bertoti, D. B. (2012). Brunnstrom's Clinical Kinesiology. (6th ed.). Philadelphia: F. A. Davis Company. Reference positions Basis from which to describe joint movements Anatomical position Anatomical position Standing in an upright posture, feet parallel and close, palms forward When a human body is in anatomical reference position, all joint angles are zero. Anatomical position Anatomical Directional Terminology Anterior - In front in relation to another structure Posterior - In back in relation to another structure Inferior (infra) - Below in relation to another structure Superior (supra) - Above in relation to another structure Distal - Situated away from the center or midline of the body Proximal - Nearest the trunk or the point of origin Lateral - On or to the side Medial - Relating to the middle or center Anatomical Directional Terminology Contralateral - Pertaining to the opposite side Ipsilateral - On the same side Bilateral - Relating to the right and left sides of the body Deep - Beneath or below the surface Superficial - Near the surface Prone - stomach lying Supine - lying on the back Body Regions Axial Cephalic (Head) Cervical (Neck) Trunk (Thoracic and Lumbar) Appendicular Upper limbs Lower limbs Planes of Motion Three planes of movement: Sagittal plane (anterior-posterior) Frontal/coronal plane (medio-lateral) Transverse/horizontal plane (rotation) Kenyon, K., & Kenyon, J. (2018). The physiotherapist's pocketbook e-book: Essential facts at your fingertips. Elsevier Health Sciences, pp 1-89 Anterolateral views of the body, illustrating the three cardinal planes (sagittal, frontal, and transverse) Examples of motion of body parts within planes. A, Motions of the head and neck and the forearm within and oblique planes. A, Two examples of sagittal planes. B, Two examples of frontal planes. C, Two the sagittal plane. B, Motions of the head and neck and the arm within the frontal plane. C, Motions of the examples of transverse planes. D, Two examples of oblique planes. (Note: The upper oblique plane head and neck and the arm within the transverse plane. D, Motions of the head and neck and the arm has frontal and transverse components to it; the lower oblique plane has sagittal and transverse within an oblique plane. components to it.) Muscolino, J. E. (2016). The muscular system manual : the skeletal muscles of the human body (Fourth edition.). Elsevier, chapter 1. A to D, Anterolateral views that illustrate the corresponding axes for the three cardinal planes and an oblique plane; the axes are shown as red tubes. A, Motion occurring in the sagittal plane around a mediolateral axis. B, Motion occurring in the frontal plane around an anteroposterior axis. C, Motion occurring in the transverse plane around a superoinferior axis, or more simply, a vertical axis. D, Motion occurring in an oblique plane; around an oblique axis. Muscolino, J. E. (2016). The muscular system manual : the skeletal muscles of the human body (Fourth edition.). Elsevier, chapter 1. Sagittal Planes of Motion Divides body into equal, bilateral segments Bisects body into 2 equal symmetrical halves or a right and left half Movements? Frontal/Coronal Planes of Motion Divides the body into (front) anterior & (back) posterior halves Movements? Transverse/Horizontal Planes of Motion Divides body into (top) superior & (bottom) inferior halves when the individual is in anatomic position Movements? Diagonal Planes of Motion Axes of motion The axis around which the movement takes place is always perpendicular to the plane in which it occurs. Axes of Rotation Mediolateral (ML) Axis Has same orientation as frontal plane of motion and runs from side to side at a right angle to sagittal plane of motion Runs medial / lateral Also known as frontal, lateral or coronal axis Axes of Rotation Anteroposterior (AP) Axis Has same orientation as sagittal plane of motion & runs from front to back at a right angle to frontal plane of motion Runs anterior / posterior Also known as sagittal axis Axes of Rotation Supra-inferior (SI) Axis Runs straight down through top of head & is at a right angle to transverse plane of motion Runs superior/ inferior Also known as long or vertical axis Axes of Rotation Diagonal or Oblique Axis Also known as the oblique axis Right angle to the diagonal plane Topics to be covered Movement Continuum Theory Anatomy and Biomechanics Underlying Movements Describing Movements – Planes of Movements Types of Movements Active vs Passive Movements Concepts Related to Muscle Strength Summary Per-Olof Åstrand (21 October 1922 – 2 January 2015) Functional movements Few activities, and therefore movements, occur in the cardinal planes. Instead, most movements occur in an infinite number of vertical and horizontal planes parallel to the cardinal planes. Characteristics: Multijoint Multimuscle Multiplanar Occurs in a functional position (needed for activities of daily living) Incorporates balance Requires core stability Yoke, M. M., & Armbruster, C. K. (2020). Methods of group exercise instruction (Fourth Edition.). Human Kinetics, p.182.  “Primary” movement patterns for ADLs * ACE identified 5 primary movements for ADLs wora Bending/raising and lifting/lowering movements (e.g. squat) Single-leg movements Pushing movements Pulling movements American Council on Exercise. (2014). ACE personal trainer Rotational movements manual. 5th ed. San Diego, CA: American Council on Exercise. But other movements have been identified too: Hinge Lunge Walking Carrying Fundamental Moves to Master – JOHO (johofitness.org) Movements of the body Joint motion that occurs only in one plane is designated as one degree of freedom; in two planes, two degrees of freedom; and in three planes, three degrees of freedom.  ‘Special movement names’ Flexion Abduction External rotation Dorsiflexion Radial deviation Lateral rotation Supination Eversion Extension Adduction Internal rotation Plantarflexion Ulnar deviation Medial rotation Pronation Inversion Neumann, D. A. (2017). Kinesiology of the musculoskeletal system foundations for rehabilitation. (3rd ed.). St Louis: Elsevier. Conjunct Rotation Best illustrated by Codman’s paradox (1934). Rotation that occurs as a result of joint surface shapes, not due to muscle contraction. Conjunct rotations can only occur in joints that can rotate internally or externally. Conjunct rotation is only under volitional control in joints with 3 df (glenohumeral, hip); if < 3 df (hinge joints, e.g. tibiofemoral, humeroulnar), conjunct rotation occurs as part of the movement but is not under voluntary control. C.f. ‘screw-home’ mechanism in knee extension; forearm and pisiform ‘supination’ during elbow Lee, S. Y., Jeong, J., Lee, K., Chung, C. Y., Lee, K. M., Kwon, S. S.,... & Park, M. S. flexion, etc. (2014). Unexpected angular or rotational deformity after corrective osteotomy. BMC Musculoskeletal Disorders, 15(1), 1-7. Wolf, S. I., Fradet, L., & Rettig, O. (2009). Conjunct rotation: Codman’s paradox revisited. Medical & Biological Engineering & Computing, 47(5), 551-556. Cheng, P. L. (2006). Simulation of Codman's paradox reveals a general law of motion. Journal of Biomechanics, 39(7), 1201-1207.  Linear and Angular Movements Two basic types of movement movement aa Linear (or translatory) - cannotconde Angular (or rotatory) So far we have been talking about mainly angular movements. Muscolino, J. E. (2017). Kinesiology : the skeletal system and muscle function (3rd edition.). Elsevier, chapter 6. Translatory (Linear) versus Rotatory (Angular) imposite no movea i out REAL near rottu - - Oatis, C. A. (2016). Kinesiology: The Mechanics and Pathomechanics of Human Movement. (3rd ed.). New York: Wolters Kluwer. Osteokinematic vs Arthrokinematic motions bone joint Osteokinematic Arthrokinematic The axis of rotation for osteokinematic The motions occurring at the joint surfaces are motions is oriented perpendicular to the termed arthrokinematic movements. plane in which the rotation occurs. The small motion, which is available at the joint These are physiologic movements. surfaces, is referred to as accessory motion, or joint-play motion. These are accessory motions. This Photo by Unknown Author is licensed under CC BY  Types of Joints Various joint structure types: immoral synarthrodial, amphiarthrodial, and skull diarthrodial (synovial); hinge, condyloid, ellipsoidal, saddle, pivot, and ball and socket. : combined/fused 1617 types syn- extent joint certain dial : a do arthro morden : hi- amp joint -on planar * At gliding xid Houglum, P. A., & Bertoti, D. B. (2012). Brunnstrom's Clinical Kinesiology. (6th ed.). Philadelphia: F. A. Davis Company.  Basics about Arthrokinematics 2 8 leg extension. knee joint in squets 2. f Three fundamental arthrokinematics that occur between curved joint surfaces: roll, slide, and spin. A, Convex-on-concave movement. B, Concave- on-convex movement. Convex-Concave Principle The small arthrokinematic motions (a few millimetres) are called accessory movements, component movements, or joint play. Without these accessory motions, normal physiologic motion is not possible. Principle states that if the bone with convex joint surface moves on the bone with concave surface, the convex joint surface slides in the direction opposite to the bone segment’s rolling motion. If the bone with the concave surface moves on the convex surface, the concave articular surface slides in the same direction as the bone segment’s roll does. Arthrokinematic Principles of Movement * Convex-on-concave surface movement: convex member rolls and slides in opposite direction. Concave-on-convex surface movement: concave member rolls and slides in the same direction.  The active arthrokinematics of knee extension. (A) Tibial-on- femoral perspective. (B) Femoral-on-tibial perspective. In both (A) and (B), the meniscus is pulled toward the contracting quadriceps. Houglum, P. A., & Bertoti, D. B. (2012). Brunnstrom's Clinical Kinesiology. (6th ed.). Philadelphia: F. A. Davis Company.  -fulle ge Closed-packed Closed-packed – surfaces of a joint’s segments match each other perfectly in only one position of congruency: versus Maximum area of surface contact occurs loose(open)- Attachments of ligaments are farthest apart and under tension packed joint Capsular structures are taut Joint is mechanically compressed, difficult to distract (separate). positions 2 Loose-packed – if joint surfaces do not fit perfectly, are incongruent Ligamentous and capsular structures are slack Joint surfaces may be distracted several millimeters Allow the necessary motions of spin, roll and slide Joint’s resting position – position at which there is least congruency and at which capsule and ligaments are loosest or most slack Topics to be covered Movement Continuum Theory Anatomy and Biomechanics Underlying Movements Describing Movements – Planes of Movements Types of Movements Active vs Passive Movements Concepts Related to Muscle Strength Summary Goniometry Measurement of range of motion Universal goniometers Electronic goniometers App-based joint range of motion measurement Active, active-assisted and passive fires muscular Active – movement driven by muscle contractions, either through shortening or lengthening move external forces > objective Passive – movement effected by examiner or gravity What are some measurement and safety issues associated with passive movements? Active-assisted – what might a challenge in measuring active-assisted movement be? End-feel “Resistance palpated by the Normal Description Example End-feel examiner when moving joint Soft tissue Knee flexion (soft tissue of posterior thigh passively to end of its range; Soft contacting soft tissue of posterior leg) bonnet approximation Jel resistance reflects joint Hip flexion with knee straight (passive Muscular stretch structure and function.” elastic tension of hamstrings muscles) Houglum, P. A., & Bertoti, D. B. (2012). Brunnstrom's Clinical Kinesiology. (6th ed.). Philadelphia: F. A. Firm Capsular stretch Extension of MCP of fingers (tension in Davis Company. anterior capsule) Forearm supination (tension in palmar radioulnar ligament of inferior radioulnar Ligamentous stretch joint, interosseous membrane, oblique cord) Elbow extension (olecranon process of Hard Bone contacting bone ulna and olecranon fossa of humerus) Norkin, C. C., & White, D. J. (2009). Measurement of joint motion: a guide to goniometry. Philadelphia: FA Davis. * Pathological End-Feel indicative of ~ End-feel Description Example Boggy feel, occurring sooner or later in ROM than is Soft tissue oedema Soft usual or in a joint that is normally has a firm or hard Synovitis end-feel. Increased muscle tonus Occurring sooner or later in ROM than is usual or in Firm Capsular, muscular, ligamentous and a joint that normally has a soft or hard end-feel. fascial shortening Chondromalacia Bony grating or bony block, occurring sooner or later Osteoarthritis Hard in ROM than is usual or in a joint that normally has a Loose bodies in joint soft or firm end-feel. Myositis ossificans Fracture Acute joint inflammation No resistance is felt. There may be patient’s Bursitis protective muscle splinting or muscle spasm. The Empty Abscess lack of end-feel is due to pain preventing the patient Fracture reaching end of ROM Psychogenic disorder Norkin, C. C., & White, D. J. (2009). Measurement of joint motion: a guide to goniometry. Philadelphia: FA Davis. Topics to be covered Movement Continuum Theory Anatomy and Biomechanics Underlying Movements Describing Movements – Planes of Movements Types of Movements Active vs Passive Movements Concepts Related to Muscle Strength Summary Movements – Concepts Related to Muscle Strength Open vs Closed kinetic chain ‘Labels’ of muscles according to ‘roles’ Passive and active insufficiency Age and gender Delayed onset muscle soreness (DOMS) Adaptation to prolonged changes in length and activity Kinematic Chain An engineering concept used to describe the interconnectedness of movement segments and muscles to describe human movements. First conceptualized by a mechanical engineer in 1875; adapted by Arthur Steindler in 1995, particularly for the analysis of human movement during sport-specific activity patterns and exercise. Kinematic chain is used in rehabilitation to describe the function or activity of an extremity or trunk in terms of a series of linked chains. Refers to a series of articulated segmented links, such as the connected pelvis, thigh, leg, and foot of the lower extremity. Two types : open vs closed  Open versus Closed Kinematic Chain dmost limit wo - el Open kinematic chain (OKC) – occurs when the distal segment of the chain “moves freely Did without any external resistance”. Closed kinematic chain (CKC) – occurs when the distal segment “meets a ‘considerable in external resistance’ that restrains free motion”. oper closed Steindler, A. (1955). Kinesiology of the Human Body. Springfield, IL: Charles C Thomas. Reed, D., Cathers, I., Halaki, M., & Ginn, K. A. (2018). Shoulder muscle activation patterns and levels differ between open and closed-chain abduction. Journal of Science and Medicine in Sport, 21(5), 462-466. Dillman, C. J., Murray, T. A., & Hintermeister, R. A. (1994). Biomechanical differences of open and closed chain exercises with respect to the shoulder. Journal of Sport Rehabilitation, 3(3), 228-238. Dillman, C. J., Murray, T. A., & Hintermeister, R. A. (1994). Biomechanical differences of open and closed chain exercises with respect to the shoulder. Journal of Sport Rehabilitation, 3(3), 228-238.  ce man de difficult ope or ce ar Image sources: https://workoutlabs.com/  muscle external force contraction speed Types of Muscle Force Generation the influencing action Isometric Force generation without muscle length changes Internal (muscle) torque = external (load) torque Concentric (positive work) Force generated through muscle shortening Internal (muscle) torque > external (load) torque Eccentric (negative work) Force generated through muscle lengthening Internal (muscle) torque < external (load) torque Dunleavy, K., & Kubo Slowik, A. (2019). Therapeutic exercise prescription. Elsevier, pp. 2-11.  diviaeos et Are these terms helpful? offen not wein Terms Definitions* Examples Muscle or muscle group that is primarily responsible for Biceps brachii contracts concentrically to bring about elbow Agonists producing a motion. An agonist actively contracts to flexion. produce a concentric, eccentric, or isometric contraction. Prime movers Agonists are sometimes referred to as prime movers. - Muscle or muscle group that is primarily responsible for Antagonists producing motion that is directly opposite the desired or Triceps brachii is the antagonist of biceps brachii. intended motion. desired motion * very important ! So Conjoint: brachioradialis working with the brachialis during produce The muscle or muscle group that assists the agonist to elbow flexion. Synergists Neutralizer: wrist extensors prevent wrist flexion when the long produce the desired motion. finger flexors contract to grasp an object. Flexor carpi radialis Conjoint Conjoint: provides identical or nearly identical activity to performs both wrist flexion and radial deviation; extensor carpi that of the agonist. radialis longus performs both wrist extension and radial Neutralizer Neutralizer: obstructs an unwanted action of the agonist deviation; when both muscles act synergistically to radially deviate the wrist while the extension and flexion actions of the Stabilizer: stabilizes proximal joints for distal joint muscles are neutralized. Stabilizer movement Fixator: scapular muscles stabilizes the scapula for humeral rotation during shoulder external/internal rotation. Muscle or muscle group that act to stabilize a bone Fixators segment in order for the muscle that attaches to it to - move the other segment. c.f. stabilizers. * Houglum, P. A., & Bertoti, D. B. (2012). Brunnstrom's Clinical Kinesiology. (6th ed.). Philadelphia: F. A. Davis Company.  Physical Activity, Exercise and Physical Fitness Physical Fitness is the outcome of PA or Exercise. PA is “any bodily movement produced by skeletal muscles that results in energy expenditure. The energy expenditure can be measured in kilocalories”. Exercise is “a planned, structured, and repetitive behavior that is performed for the purpose of improving or maintaining physical fitness”. Gordon, Chambliss, H., Durstine, J. L., Jett, D. M., & Ross, L. M. (Eds.). (2022). ACSM’s resources for the exercise physiologist : a practical guide for the health fitness professional (Third edition.). Wolters Kluwer. Chapter 1.  Muscle Strength Training Muscle strengthening fore generate maximumuse can becom Exercises to increase muscle strength and muscle endurance; “resistance exercise is a often considered “medicine” due to the well-established benefits associated with this type of training”. 7 fundamental PROCESS principles for resistance training programming : (a) Progression, (b) Regularity, (c) Overload, (d) Creativity, (e) Enjoyment, (f) Specificity, and (g) Supervision. Muscle re-education Suretiend Focus on engaging the neuromuscular system to remember how it works/acts before injury or surgery. Aim is to “provide feedback that will reestablish neuromuscular control or promote the ability of a muscle or group of muscles to contract. It may also be used to regain normal agonist/antagonist muscle action and for postural control retraining.” Gordon, Chambliss, H., Durstine, J. L., Jett, D. M., & Ross, L. M. (Eds.). (2022). ACSM’s resources for the exercise physiologist : a practical guide for the health fitness professional (Third edition.). Wolters Kluwer. Chapter 4. Prentice W.E. (2017). Biofeedback. Prentice W.E., & Quillen W, & Underwood F(Eds.), Therapeutic Modalities in Rehabilitation, 5e. McGraw Hill. https://accessphysiotherapy.mhmedical.com/content.aspx?bookid=2223&sectionid=173786320 * Passive Insufficiencyconcepta langthe When muscles become elongated over two or more joints simultaneously, they may reach the state of passive insufficiency. Passive tension of muscles that cross two or more joints may produce passive movements of those joints. This effect is called tenodesis (Gr. tenon, tendon; desis, a binding together) action of muscle. Se kee So O Due O Houglum, P. A., & Bertoti, D. B. (2012). Brunnstrom's Clinical Kinesiology. (6th ed.). Philadelphia: F. A. Davis Company. Passive Insufficiency ↓ Figure 4.15 Tenodesis occurs in the long ① finger flexors and extensors with movement of the wrist. A) The hand and wrist in a resting position. B) As the wrist flexes, the passive insufficiency of the long finger extensors causes the fingers to move into extension. C) As the wrist extends, the passive insufficiency of the long finger flexors moves the fingers passively into flexion Houglum, P. A., & Bertoti, D. B. (2012). Brunnstrom's Clinical Kinesiology. (6th ed.). Philadelphia: F. A. Davis Company. Active Insufficiency Active insufficiency occurs in multi-joint muscles when the muscle is at its shortest length when its ability to produce physiologic force is minimal. Figure 4.16 Active insufficiency. A) When a muscle is at its shortest, its ability to produce tension is at its lowest so finger flexors are unable to provide a strong grip when the wrist is flexed along with the finger flexors. B) By lengthening the muscle at another joint the muscle crosses, the muscle’s strength is maintained, so if the wrist extends, the finger flexors have enough length to provide a strong grip. Houglum, P. A., & Bertoti, D. B. (2012). Brunnstrom's Clinical Kinesiology. (6th ed.). Philadelphia: F. A. Davis Company. Age and Gender · Soci biochemical Komi, P. V., & Karlsson, J. (1978). Physical performance, skeletal muscle enzyme activities, and fibre types in monozygous and dizygous twins of both sexes. Acta Physiologica Scandinavica. Supplementum, 462, 1-28.  and pedit mining same is man fur women d Lindle, R. S., Metter, E. J., Lynch, N. A., Fleg, J. L., Fozard, J. L., Tobin, J.,... Hurley, B. F. (1997). Age and gender comparisons of muscle strength in 654 women and men aged 20–93 yr. Journal of Applied Physiology, 83(5), 1581-1587. Delayed Onset Muscle Soreness A form of ‘muscle injury’ following unaccustomed physical activity, accompanied by a sensation of discomfort, predominantly within the skeletal muscle; usu. eccentric action Usually in elite or novice athlete Intensity of discomfort increases within first 24 hours following cessation of exercise Peaks between 24 and 72 hours Subsides and eventually disappears by 5–7 days post-exercise Pain, stiffness, inability to contract are the main complaints Integrative theories explaining DOMS Cheung, K., Hume, P. A., & Maxwell, L. (2003). Delayed Onset Muscle Soreness. Sports Medicine, 33(2), 145-164. Adaptation to Prolonged Length Changes Prolonged muscle lengthening Prolonged muscle shortening Hypertrophy effect Atrophy effect  protein synthesis,  sarcomeres ->  sarcomeres -> peak contractile force  peak contractile force  Length-tension relationship maintained  sarcomeres in series ->  overall Muscles transition from type I to II fibres muscle fibre length, this remodeling maintains its length–tension relationship Mostly immobilization studies, so caution with generalizing to postural abnormalities Some muscles transition from type II to type I fibre Oatis, C. A. (2016). Kinesiology: The Mechanics and Pathomechanics of Human Movement. (3rd ed.). New York: Wolters Kluwer. Adaptation to Prolonged Activity Changes (DUH) GD BAD Prolonged activity/use Prolonged disuse Hypertrophy effect Atrophy effect CSA Resistance training  cross-sectional Disuse induces  CSA of both types of areas of type I and II fibres-> muscle force muscle fibres  Transition from type I to II fibres Changes in CSA of type II > I Unique cases in microgravity environment Some evidence (animals) of transition (i.e. in space) and ageing from type IIb to I Oatis, C. A. (2016). Kinesiology: The Mechanics and Pathomechanics of Human Movement. (3rd ed.). New York: Wolters Kluwer. Topics to be covered Movement Continuum Theory Anatomy and Biomechanics Underlying Movements Describing Movements – Planes of Movements Types of Movements Active vs Passive Movements Concepts Related to Muscle Strength Summary Summary Movements are described referenced to specific planes and axes. Not all movements occur in the cardinal planes; implies that precise description is necessary for movement analysis. /convex Movements can be translatory or rotatory. > concave Movements may be described as active, active-assisted or passive. End-feels are resistance to passive movement at the end of range of movement. Open and closed-chain is another way to describe movements. In active movements, muscles contract to produce the force for movements. They can generate tension through shortening (concentric), lengthening (eccentric) or without change in muscle length or range of motion (isometric). The convex-concave rule describes the relationship of translatory and rotatory movements occurring at a joint.  Posture http://pranayoga.co.in/asana/wp-content/uploads/posture-chart-final-Copy.png Alan Wong, PhD [email protected] References Kendall, F. P., McCreary, E. K., Provance, P. G., Rodgers, M. M., & Romani, W. A. (2005). Muscles, testing and function: with posture and pain. (5th ed.). Baltimore, MD: Lippincott Williams & Wilkins. Johnson. (2012). Postural assessment. Human Kinetics. https://singaporetech.primo.exlibrisgroup.com/permalink/65SIT_INST/1i4buil/alma9910008004 95204056 Slater, D., Korakakis, V., O'Sullivan, P., Nolan, D., & O'Sullivan, K. (2019). “Sit up straight”: time to Re-evaluate. Journal of orthopaedic & sports physical therapy, 49(8), 562-564. O'Sullivan, K., O'Sullivan, P., O'Sullivan, L., & Dankaerts, W. (2012). What do physiotherapists consider to be the best sitting spinal posture?. Manual therapy, 17(5), 432-437. Korakakis, V., O'Sullivan, K., O'Sullivan, P. B., Evagelinou, V., Sotiralis, Y., Sideris, A.,... & Giakas, G. (2019). Physiotherapist perceptions of optimal sitting and standing posture. Musculoskeletal Science and Practice, 39, 24-31. References Raine, S., & Twomey, L. (1994). Posture of the head, shoulders and thoracic spine in comfortable erect standing. Australian Journal of Physiotherapy, 40(1), 25-32. Refshauge, K., Goodsell, M., & Lee, M. (1994). Consistency of cervical and cervicothoracic posture in standing. Australian Journal of Physiotherapy, 40(4), 235-240. Booshanam, D. S., Cherian, B., Joseph, C. P. A., Mathew, J., & Thomas, R. (2011). Evaluation of posture and pain in persons with benign joint hypermobility syndrome. Rheumatology international, 31(12), 1561-1565. Glista, J., Pop, T., Weres, A., Czenczek-Lewandowska, E., Podgórska-Bednarz, J., Rykała, J.,... & Rusek, W. (2014). Change in anthropometric parameters of the posture of students of physiotherapy after three years of professional training. BioMed research international, 2014. Britnell, S. J., Cole, J. V., Isherwood, L., Stan, M. M., Britnell, N., Burgi, S.,... & Watson, L. (2005). Postural health in women: the role of physiotherapy. Journal of obstetrics and gynaecology Canada, 27(5), 493-500. References Wilkes, C., Kydd, R., Sagar, M., & Broadbent, E. (2017). Upright posture improves affect and fatigue in people with depressive symptoms. Journal of behavior therapy and experimental psychiatry, 54, 143-149. Chansirinukor, W., Wilson, D., Grimmer, K., & Dansie, B. (2001). Effects of backpacks on students: measurement of cervical and shoulder posture. Australian Journal of physiotherapy, 47(2), 110-116. Lomas-Vega, R., Garrido-Jaut, M. V., Rus, A., & del-Pino-Casado, R. (2017). Effectiveness of global postural re-education for treatment of spinal disorders: a meta-analysis. American journal of physical medicine & rehabilitation, 96(2), 124-130. Assessing Posture Here are three people. - One has had chest surgery 2 - One has hypermobile joints 3 - One has very tight external hip rotators. Can you tell which is which by looking at these photographs? Johnson, J. (2012). Introduction to Postural Assessment. In Postural Assessment: Hands-On Guides for Therapists (pp. 3–14). Champaign, IL: Human Kinetics. Retrieved August 20, 2023, from http://dx.doi.org/10.5040/9781718209619.ch-001  hypermobile chest sungey light hip morefore Johnson, J. (2012). Introduction to Postural Assessment. In Postural Assessment: Hands-On Guides for Therapists (pp. 3–14). Champaign, IL: Human Kinetics. Retrieved August 20, 2023, from http://dx.doi.org/10.5040/9781718209619.ch-001  "Good posture is that state of muscular and skeletal balance which protects the supporting structures of the body against injury or progressive deformity irrespective of the attitude What is Good (erect, lying, squatting, stooping) in which these Posture? structures are working or resting. Under such conditions the muscles will function most efficiently and the optimum positions are afforded for the thoracic and abdominal organs." American Academy of Orthopaedic Surgeons (AAOS), 1949, quoted by Kendall, F. P., McCreary, E. K., Provance, P. G., Rodgers, M. M., & Romani, W. A. (2005). Muscles, testing and function: with posture and pain. (5th ed.). Baltimore, MD: Lippincott Williams & Wilkins.  parts of body other hande worke to need T to compensate Poor posture is "... a faulty relationship of the various parts of the body What is Poor which produces increased strain on the Posture? supporting structures and in which there is less efficient balance of the body over its base of support." Posture Committee of the American Academy of Orthopaedic Surgeons (AAOS), 1947, quoted by Kendall, F. P., McCreary, E. K., Provance, P. G., Rodgers, M. M., & Romani, W. A. (2005). Muscles, testing and function: with posture and pain. (5th ed.). Baltimore, MD: Lippincott Williams & Wilkins. Posture Ideal posture ensures physiological and biomechanical efficiency, reduces undue stress and strain on bones, joints, ligaments and muscles. symptoms Faulty or non-ideal (and habitual) posture may be related to pain, discomfort, muscle weakness or tightness. Faulty alignment results in undue stress and strain. Joint positions in faulty posture indicate muscles that are weak or tight. Kendall, F. P., McCreary, E. K., Provance, P. G., Rodgers, M. M., & Romani, W. A. (2005). Muscles, testing and function: with posture and pain. (5th ed.). Baltimore, MD: Lippincott Williams & Wilkins, pp.49-95  What Does Research Say About Posture? Physiotherapists differ in their professional opinion of the optimal sitting/standing posture although majority (>40%) prefer upright sitting/standing with normal lumbar spine lordosis (O’Sullivan et al., 2012; Korakakis et al., 2019). There is limited evidence supporting a correlation between spinal symptoms and poor sitting/standing postures (O’Sullivan et al., 2012) whereas some researchers have found some evidence that supports posture correction improves spinal symptoms (Lomas-Vega et al., 2017) Forces acting on the body can affect posture, e.g. carrying a backpack weighing 15% of body weight appeared to be too heavy to maintain head and shoulder posture in standing for adolescents (Chansirinukor et al., 2001). Forward head posture appears to be related to thoracic kyphosis, rather than rounded shoulders or upper cervical extension (Raine & Twomey, 1994). Posture re-education by physiotherapists is important for people with benign joint hypermobility (Booshanam et al., 2011), for women during or after pregnancy (Britnell et al., 2005) and improves arousal/reduce fatigue in depressive conditions (Wilkes et al., 2017). PT students appear to have poorer posture at the end of their studies (Glista et al., 2014)! * Plumb Line Test When viewed from the side, the body is observed in relation to a real or imaginary plumb line that hangs just in front of the centre of the ankle joint. In ideal alignment, the plumb line – bisects the ear bisects the shoulder joint runs down the bodies of the lumbar vertebrae bisects the greater trochanter of the femur runs just behind the centre of the knee runs just in front of the centre of the ankle The point of reference is at the base, hence aligned to a point just anterior to the lateral malleolus.  Observation A core competency of Physiotherapist Passier, L. N., Nasciemento, M. P., Gesch, J. M., & Haines, T. P. (2010). Physiotherapist observation of head and neck alignment. Physiotherapy theory and practice, 26(6), 416-423. Kendall, F. P., McCreary, E. K., Provance, P. G., Rodgers, M. M., & Romani, W. A. (2005). Muscles, testing and function: with posture and pain. (5th ed.). Baltimore, MD: Lippincott Williams & Wilkins. # Ideal Plumb Alignment Head and Neck Upper Back Shoulder Side: through the lobe of Side: slight curve Side: midway through the the ear shoulder Back: equidistant of Back: spinous processes of scapulae from the vertebral Back: scapulae flat against cervical spine column upper back, approx. T2 to T7 level Pelvis and Low Back Hips and Knees Ankles and Feet Side: pelvis in neutral Side: slight posterior to hip Side: slight anterior to position, normal low back joint (through greater lateral malleolus and apex curvature; midway of trunk trochanter) and slight anterior of arch (calcaneocuboid to knee joint joint) Back: bilat. PSIS are level Back: level gluteal folds Back: heels equidistant apart Factors Affecting Posture (1) Structural or anatomical Scoliosis in all or part of the spine Discrepancy in the length of the long bones in the upper or lower limbs Extra ribs Extra vertebrae Increased elastin in tissues (decreasing the rigidity of ligaments) > Marten's syndrome Age Posture changes considerably as we grow into our adult forms, with postures in children being markedly different at different ages. Physiological Posture changes temporarily in a minor way when we feel alert and energised compared to when we feel subdued and tired. Pain or discomfort may affect posture as we adopt positions to minimise discomfort. This may be temporary or could result in long-term postural change if the position is maintained. Physiological changes that accompany pregnancy are temporary (e.g., low backache before or after childbirth), but sometimes result in more permanent, compensatory postural change. Factors Affecting Posture (2) Pathological Illness and disease affect our postures especially when bones and joints are involved. Osteomalacia may show up as genu varum; arthritic changes are often revealed when joints in the limbs are observed. Pain can lead to altered postures as we attempt to minimise discomfort (e.g., following a whiplash injury a client may hunch the shoulders protectively; abdominal pain may lead to spinal flexion). Mal-alignment in the healing of fractures may sometimes be observed as a change in bone contour. Certain conditions may lead to an increase or a decrease in muscle tone. For example, someone who has suffered a stroke may have increased tone in some limbs but decreased tone in others. As elderly adults, we tend to lose height as a result of osteoporotic changes and so develop stooped postures; postmenopausal women may develop a dowager’s hump. Factors Affecting Posture (3) Occupational Consider the postural differences between a manual worker and an office worker, and between someone active and someone sedentary. Recreational Consider the postural differences between someone who plays regular racket sports and someone who is a committed cyclist. Environmental When people feel cold they adopt a different posture to that when they feel warm. Social and cultural People who grow up sitting cross-legged or squatting develop postures that are different from those of people who grow up sitting on chairs. Johnson, J. (2012). Introduction to Postural Assessment. In Postural Assessment: Hands-On Guides for Therapists (pp. 3–14). Champaign, IL: Human Kinetics. Retrieved August 20, 2023, from http://dx.doi.org/10.5040/9781718209619.ch-001 Factors Affecting Posture (4) Emotional Usually, the posture we subconsciously adopt to match certain moods is temporary, but in some cases it persists if the emotional state is habitual. Consider the posture of a person who is grieving, or the muscle tone of a person who is angry. Clients who fear pain may adopt protective postures. arsident pain behavious Johnson, J. (2012). Introduction to Postural Assessment. In Postural Assessment: Hands-On Guides for Therapists (pp. 3–14). Champaign, IL: Human Kinetics. Retrieved August 20, 2023, from http://dx.doi.org/10.5040/9781718209619.ch-001  Four types of postural alignments Kendall, F. P., McCreary, E. K., Provance, P. G., Rodgers, M. M., & Romani, W. A. (2005). Muscles, testing and function: with posture and pain. (5th ed.). Baltimore, MD: Lippincott Williams & Wilkins. 1. ‘Ideal’ Segmental Alignment Head: Neutral position, not tilted forward or back Cervical spine: Normal curve, slightly convex anteriorly Scapulae: Flat against upper back Thoracic spine: Normal curve, slightly convex posteriorly normal kyphosis Lumbar spine: Normal curve, slightly convex anteriorly normal verdosis Pelvis: Neutral position, ASISes in the same vertical plane as symphysis pubis Hip joints: Neutral position, neither flexed nor extended Knee joints: Neutral position, neither flexed nor hyperextended Ankle joints: Neutral position, leg vertical and at a right angle to the sole of the foot Kendall, F. P., McCreary, E. K., Provance, P. G., Rodgers, M. M., & Romani, W. A. (2005). Muscles, testing and function: with posture and pain. (5th ed.). Baltimore, MD: Lippincott Williams & Wilkins. 2a. Kyphotic-Lordotic Posture Head: Forward a ↑ Cervical spine: Hyperextended evie dis Scapulae: Abducted Thoracic spine: Kyphotic (increased flexion) Lumbar spine: Lordosis (hyperextended) Pelvis: Anteriorly tilted lumbo pelvic rhythm Hip joints: Flexed Knee joints: Slight hyperextended Ankle joints: Slight plantarflexed because of backward inclination of the leg Which muscles tend to be weak? Which muscles tend to be tight? Kendall, F. P., McCreary, E. K., Provance, P. G., Rodgers, M. M., & Romani, W. A. (2005). Muscles, testing and function: with posture and pain. (5th ed.). Baltimore, MD: Lippincott Williams & Wilkins. 2b. Lordotic Posture Head: Neutral position Cervical spine: Normal curve (slight anterior) Thoracic spine: Normal curve (slight posterior) Lumbar spine: Lordosis (hyperextended) Pelvis: Anteriorly tilted Hip joints: Flexed Knee joints: Slight hyperextended Ankle joints: Slight plantarflexed Which muscles tend to be weak? Which muscles tend to be tight? Kendall, F. P., McCreary, E. K., Provance, P. G., Rodgers, M. M., & Romani, W. A. (2005). Muscles, testing and function: with posture and pain. (5th ed.). Baltimore, MD: Lippincott Williams & Wilkins. 3. Flat-Back Posture Head: Forward Cervical spine: Slightly extended mana , Thoracic spine: Upper part - increased loss of kyphosis flexion; lower part - straight Lots of Lumbar spine: Flexion (straight) hordosis Pelvis: Posteriorly tilted Hip joints: Extended Knee joints: Extended Ankle joints: Slight plantarflexion Which muscles tend to be weak? Which muscles tend to be tight? Kendall, F. P., McCreary, E. K., Provance, P. G., Rodgers, M. M., & Romani, W. A. (2005). Muscles, testing and function: with posture and pain. (5th ed.). Baltimore, MD: Lippincott Williams & Wilkins. 4. Sway-Back Posture Head: Forward Cervical spine: Slightly extended Thoracic spine: Increased flexion (long kyphosis) with posterior displacement of the upper trunk [ Lumbar spine: Flexion (flattening) of the lower lumbar area ofkyphosa a lose Pelvis: Posteriorly tilted Hip joints: Hyperextended with anterior displacement of the pelvis Knee joints: Hyperextended Ankle joints: Neutral Which muscles tend to be weak? Which muscles tend to be tight? Kendall, F. P., McCreary, E. K., Provance, P. G., Rodgers, M. M., & Romani, W. A. (2005). Muscles, testing and function: with posture and pain. (5th ed.). Baltimore, MD: Lippincott Williams & Wilkins.  > - PSIS-Asis Pelvic Tilt < Ass > - psis Asymptomatic normal individuals: Ave. 8.35° SD 4.17 (range 1.99°-15.72°) (Gajdosik et al., 1985). Cadavers: Ave. 13° SD 5 (range 0-23°) (Preece et al 2011). What is ‘normal’? (Herrington 2011) Among 65 male: 85% - anterior tilt 6% - posterior tilt 9% - neutral Among 55 female: 75% - anterior tilt Gajdosik, R., Simpson, R., Smith, R., & DonTigny, R. L. (1985). Pelvic tilt: Intratester reliability of measuring the standing position 7% - posterior tilt and range of motion. Physical Therapy, 65(2), 169-174. 18% - neutral Herrington, L. (2011). Assessment of the degree of pelvic tilt within a normal asymptomatic population. Manual Therapy, 16(6), 646-648. Preece, S. J., Willan, P., Nester, C. J., Graham-Smith, P., Herrington, L., & Bowker, P. (2008). Variation in pelvic morphology may prevent the identification of anterior pelvic tilt. Journal of Manual & Manipulative Therapy, 16(2), 113-117. Le Huec, J. C., Aunoble, S., Philippe, L., & Nicolas, P. (2011). Pelvic parameters: origin and significance. European Spine Journal, 20(5), 564. Kendall, F. P., McCreary, E. K., Provance, P. G., Rodgers, M. M., & Romani, W. A. (2005). Muscles, testing and function: with posture and pain. (5th ed.). Baltimore, MD: Lippincott Williams & Wilkins. Posterior View – Ideal Alignment Head: Neutral, not tilted nor rotated Cervical spine: Slight lateral flexion Shoulders: Level, not elevated nor depressed Scapulae: Neutral, medial borders parallel Thoracic and lumbar spines: Straight Pelvis: Level, both PSISes in same horizontal plane Hip joints: Neutral, not abducted nor adducted Lower extremities: Straight, not bowed nor knocked Feet: Parallel, neither pronated nor supinated Kendall, F. P., McCreary, E. K., Provance, P. G., Rodgers, M. M., & Romani, W. A. (2005). Muscles, testing and function: with posture and pain. (5th ed.). Baltimore, MD: Lippincott Williams & Wilkins. Posterior View – Faulty Alignment 1 Head: Erect, not tilted nor rotated Cervical spine: Straight Shoulders: Right -> low f Scapulae: Adducted, right -> slightly depressed Thoracic and lumbar spines: Curve · convex to the left · Pelvis: Lateral tilt, right -> higher Hip joints: Right -> adducted, slightly medial rotated; left -> abducted Lower extremities: Straight, not bowed nor knocked Feet: Slight pronated What muscles are likely to be ‘elongated and weak’ or ‘short and tight’? Kendall, F. P., McCreary, E. K., Provance, P. G., Rodgers, M. M., & Romani, W. A. (2005). Muscles, testing and function: with posture and pain. (5th ed.). Baltimore, MD: Lippincott Williams & Wilkins. Posterior View – Faulty Alignment 2 Head: Erect, not tilted nor rotated Cervical spine: Straight Shoulders: Elevated and adducted. Joints are medially rotated as indicated by hand g position facing posteriorly Scapulae: Adducted and elevated Thoracic and lumbar spines: Slight convex Reha in to the right Pelvis: Lateral tilt, left -> higher Hip joints: Left -> adducted, slightly medial rotated; right -> abducted Lower extremities: Straight, not bowed nor knocked Feet: Slightly pronated What muscles are likely to be ‘elongated and weak’ or ‘short and tight’? Kendall, F. P., McCreary, E. K., Provance, P. G., Rodgers, M. M., & Romani, W. A. (2005). Muscles, testing and function: with posture and pain. (5th ed.). Baltimore, MD: Lippincott Williams & Wilkins. Summary Posture analysis as an introduction to understanding human movements. Faulty postures may or may not be related to muscle weakness (tendency to be elongated) and tightness (tendency to be short). Identifying faulty postures help physiotherapists decide whether to test muscle weakness/tightness. There is a need to correlate with symptoms. Developing observational skills. PTY1016 Foundation of Physiotherapy: Movement Biomechanics Basic Concepts of Mechanics of Biological Tissues Alan Wong, PhD, MPH [email protected] Kinetic Concepts Forces Gravity Muscles Externally applied resistances Friction Types of Forces on Musculoskeletal System The manner by which forces or loads are most frequently applied to the musculoskeletal system is shown. The combined loading of torsion and compression is also illustrated. Neumann, D. A. (2017). Kinesiology of the musculoskeletal system : foundations for rehabilitation (Third edition.). Elsevier. Basic Mechanics Concepts – (1) Stress Stress (σ) is a physical quantity. The stress is the force per unit area applied to the material. Basic Mechanics Concepts – (2) Strain Stresses lead to strain (or deformation). Putting pressure on an object causes it to stretch. Strain is a measure of how much an object is being stretched. Stress and Strain Elastic Modulus Stress divided by strain is defined as the modulus of elasticity an indicator of an object's likelihood to deform when a force is applied. Page 17 Basic Mechanics Concepts – Stress-Strain Curves Ref: Nihat Özkaya and Margareta Nordin. Fundamentals of Biomechanics: Equilibrium, Motion, and Deformation. 2nd ed. Springer; 1999. Tensile Stress-Strain Response There are 3 distinct regions in the stress- strain curve: Initial linearly elastic region where slope = elastic modulus (E). Intermediate region – exhibit yielding & nonlinear elasto- plastic material behaviour. Final region – exhibits linear plasticity where slope = strain hardening modulus. In biological tissues: therapeutic range - > Dunleavy, K., & Kubo Slowik, A. (2019). Therapeutic exercise prescription. Elsevier, chapter 1. In biological tissues: Dunleavy, K., & Kubo Slowik, A. (2019). Therapeutic exercise prescription. Elsevier, chapter 1. Stress-strain Relationship The stress-strain relationship of an excised ligament that has been stretched to a point of mechanical failure (disruption). Neumann, D. A. (2017). Kinesiology of the musculoskeletal system : foundations for rehabilitation (Third edition.). Elsevier. * Viscoelasticity All connective tissues are viscoelastic materials, i.e. fluid-like component to their behaviour Viscosity – material's resistance to flow (a fluid property) High-viscosity fluids (e.g., honey) flow slowly. Lower-viscosity fluids (e.g., water) flow quickly. Decreases with temperature and slowly applied loads Elasticity – material’s ability to return to its original length or shape after the removal of deforming load. Length changes or deformations are proportional to applied forces/loads. Depend on connective tissue’s collagen and elastin content and organization. When stretched, work is done (= force x distance) and energy in stretched material increases. Oatis, C. A. (2016). Kinesiology: The Mechanics and Pathomechanics of Human Movement. (3rd ed.). New York: Wolters Kluwer. Levangie, P. K., & Norkin, C. C. (2011). Joint structure and function a comprehensive analysis. (5th ed.). Philadelphia: F.A. Davis. Time- and rate-dependent properties Viscoelastic materials deform under either tensile or compressive forces, but return to their original state after removal of the force Creep Stress-relaxation Strain-rate sensitivity Hysteresis Levangie, P. K., & Norkin, C. C. (2011). Joint structure and function a comprehensive analysis. (5th ed.). Philadelphia: F.A. Davis.  Time- and rate-dependent properties of dense connective tissues. A. Creep: When the tissue is loaded to a fixed force level, and length is measured, the latter increases with time (T0 to T1) and the tissue recovers its original length in a nonlinear manner (T1 to T0). (From Oskaya N, Nordin M: Fundamentals of Biomechanics, Equilibrium Motion and Deformation [ed. 2]. New York, Springer-Verlag, 1999, with permission from the publisher as well as the author, Margarita Nordin.) Levangie, P. K., & Norkin, C. C. (2011). Joint structure and function a comprehensive analysis. (5th ed.). Philadelphia: F.A. Davis. Creep Progressive strain (deformation) of a material when under a constant load over time. A phenomenon of viscoelasticity, and therefore common in human tissue. What are some examples for clinical practice?  Time- and rate-dependent properties of dense connective tissues. B. Force or stress-relaxation: If the tissue is stretched to a fixed length and held there, the force needed to maintain this length will decrease with time. (From Oskaya N, Nordin M: Fundamentals of Biomechanics, Equilibrium Motion and Deformation [ed. 2]. New York, Springer-Verlag, 1999, with permission from the publisher as well as the author, Margarita Nordin.) Levangie, P. K., & Norkin, C. C. (2011). Joint structure and function a comprehensive analysis. (5th ed.). Philadelphia: F.A. Davis. Stress Relaxation Stress relaxation is the reduction of stress within a material over time as the material is subjected to a constant deformation. When applying and maintaining a fixed displacement, or strain, the resisting force (from which stress is calculated) can be measured as a function of time. Stress generally decreases with time and hence the label “relaxation.”  Both creep and stress relaxation are important behaviors in biological soft tissue.  What are some examples of stress relaxation in human movement?  Time- and rate-dependent properties of dense connective tissues. C. Hysteresis: As the tissue is loaded and unloaded, some energy is dissipated through tissue elongation and heat release. (From Oskaya N, Nordin M: Fundamentals of Biomechanics, Equilibrium Motion and Deformation [ed. 2]. New York, Springer-Verlag, 1999, with permission from the publisher as well as the author, Margarita Nordin.) - Levangie, P. K., & Norkin, C. C. (2011). Joint structure and function a comprehensive analysis. (5th ed.). Philadelphia: F.A. Davis. Hysteresis When force is applied (loaded) and removed (unloaded) to a structure, the resulting load- deformation curves do not follow the same path. Not all of the energy gained as a result of the lengthening work (force x distance) is recovered during the exchange from energy to shortening work. Some energy is lost, usually as heat.  Time- and rate-dependent properties of dense connective tissues. D. If the tissue is loaded rapidly, f Better more energy (force or stress) is required to deform the tissue. (From Oskaya N, Nordin M: Fundamentals of Biomechanics, Equilibrium Motion and Deformation [ed. 2]. New York, Springer- Verlag, 1999, with permission from the publisher as well as the author, Margarita Nordin.) Levangie, P. K., & Norkin, C. C. (2011). Joint structure and function a comprehensive analysis. (5th ed.). Philadelphia: F.A. Davis. Strain-rate sensitivity Most tissues behave differently if loaded at different rates. When a load is applied rapidly, the tissue is stiffer, and a larger peak force can be applied to the tissue than if the load was applied slowly. The subsequent stress-relaxation also will be larger than if the load was applied slowly. Creep will take longer to occur under conditions of rapid loading. What are some examples of clinical applications? Levangie, P. K., & Norkin, C. C. (2011). Joint structure and function a comprehensive analysis. (5th ed.). Philadelphia: F.A. Davis. PTY1016 Foundation of Physiotherapy: Movement Biomechanics Biomechanics of the Bone, Joint and Soft Tissues Alan Wong, PhD, MPH, BPhty(Hons) [email protected] Biological Tissues Biological tissues can be classified as : Hard – e.g. bone, teeth. Soft – Tendons, ligaments, joint capsules, skin, muscles, articular cartilage. Page Fracture Bone fractures heal by forming bone callus at the site of fracture. When a bone is fractured, blood pours into the injured area to form a clot. This is known as a fracture haematoma and its role is to act as a provisional scaffold for migration of cells and a source of growth factors released by the haematopoietic cells trapped in the haematoma. These growth factors induce the migration and proliferation of osteoblasts, fibroblasts and mesenchymal cells, which form a type of granulation tissue around each fracture end, thus forming a bridge between the separated ends. In the first week of injury, the granulation tissue gives rise to islands of cartilaginous procallus, also known as soft callus , to anchor the broken ends together. Within two to three weeks, through a process known as endochondral ossification, the soft callus is slowly converted to a hard bony framework to further stabilise the connection between the separated ends. Between four to 16 weeks, the callus is remodelled so that the cartilaginous structure converts to calcified bone matrix and the bone is shaped to return towards the near-normal shape and function, including clear separation of the medullary cavity from the compact bone. The most important factors that influence bone healing include blood supply, mechanical stability, the location of the injury and bone loss due to age-associated changes or the extent of trauma to the bone. Patient diet also has an impact on the quality of formed bone; for example, nutritional deficiencies in calcium and vitamin D or loss of capacity to absorb calcium through procedures such as gastric bypass. Medication prescribed, such as bisphosphonates, also affects a patient's Tomkins, Z. (2020). Applied Anatomy & Physiology : an interdisciplinary approach. capacity to generate good-quality bone. Elsevier, pp. 279-304. Bone Tissue Bone is the primary structural element of the human body Supports and protects the internal organ. Assists movement: Sites for muscle attachment Facilitates muscle actions and body movement Mineral “bank”: Reservoir for calcium deposit to maintain homeostasis of blood calcium Blood cell production: Hemopoiesis (red marrow) Energy storage: Adipose tissue (yellow marrow) Page Types of the Bones Patton, K. T., & Thibodeau, G. A. (2019). Anatomy & physiology ([Adapted International edition].). Elsevier, chapter 11. Long Bone Patton, K. T., & Thibodeau, G. A. (2019). Anatomy & physiology ([Adapted International edition].). Elsevier, chapter 11. Flat and other bones Patton, K. T., & Thibodeau, G. A. (2019). Anatomy & physiology ([Adapted International edition].). Elsevier, chapter 11. Composition of the Bone Biologically, bone is a connective tissue which binds together various structure of the body. Mechanically, bone is a composite material with various solid and fluid phases. Bone contains inorganic components which makes it hard and rigid and organic components which provide the flexibility. https://in.pinterest.com/pin/773000723516028291/ Composition of the Bone There are two types of bone tissue: 1 Cortical or compact bone tissue is a dense material forming outer shell (cortex) of bones. 2 Cancellous, trabecular, or spongy bone tissue consists of thin plates (trabeculae) in a loose mesh structure enclosed by the cortical bone. Bones are surrounded by a dense fibrous membrane called the periosteum and covers entire bone except for the joint surfaces which are covered by articular cartilage. Spongy Bone vs. Compact Bone: What's the Difference? https://www.pinterest.com/pin/718676053017868345/ # Mechanical Properties of the Bone Major factors influencing mechanical behavior of bone: Composition of bone. Mechanical properties of tissues comprising the bone. Size and geometry of bone. Direction, magnitude, and the rate of applied loads. I how fast Page 33 Mechanical Properties of the Bone Bone can be characterised as: Nonhomogeneous material as it consists of various cells, organic and inorganic substances with different material properties. Anisotropic (direction dependent) as material properties is different when acted - - - upon in different directions. Viscoelastic (time and rate dependent), e.g., bone can resist rapidly applied load much better than slowly applied loads. Hence, bone is stiffer and stronger at higher strain rates. Page 34 Effects of Anisotropy Stress-strain behavior is dependent on orientation of bone with respect to direction of loading. - stiffest - less stiff Page 35 Effects of Anisotropy Table: Mechanical properties for cortical bone Example: Cortical bone Loading Mode Ultimate Strength Has larger ultimate strength (MPa) (ie stronger) and a larger Longitudinal elastic modulus (ie stiffer) in Tension 133 the longitudinal than Compression 193 Transverse transverse direction. Tension 51 Also, it is more brittle (w/o Compression 133 yielding) as compared to bone ELASTIC MODULI, E specimens loaded in longitudinal Longitudinal 17.0GPa direction. Transverse 11.5GPa SHEAR MODULUS,G 3.3GPa An experiment to demonstrate Anisotropic behavior Viscoelastic Property of the Bone Page 25 Comparison of Mechanical Properties Between Cortical and Cancellous Bones D Structural Integrity of the Bone Factors affecting integrity of bone: Osteoporosis reduces bone integrity in terms of strength and stiffness by reducing apparent density. Surgery altering normal bone geometry. Bone defects. - usually congenital Screw holes for pins & bone plates can cause stress concentrations on bone. wedeed - on bar Bone fracture occurs when stresses generated in bone exceeds the ultimate strength of bone. Osteoporosis Osteoporosis is the most epidemic bone disease in older populations. It is characterized by: low bone mass, deterioration of bone micro-architecture, compromised bone strength. It leads to bone fragility and increased risk of fracture under low loads. Biomechanics of Soft Tissues Page 29 Musculoskeletal Soft Tissues Types of soft tissues Articular Cartilage Tendon Ligament Muscle Joint Capsules Skin Others Composition of the Soft Tissues All soft tissues are composite materials. Collagen and elastin fibers made up the main structural elements of soft tissues. Collagen Fibers Collagen fibres are not effective under compression. When stretched, energy is stored in the fiber like a spring. When release, energy returns to the fiber to its unstretched state. Individual fibrils of the collagen fibers are surrounded by a gel-like ground substance, which consists mainly of water. Collagen fibre possesses a two-phase, solid-fluid, or viscoelastic material behavior. Elastin Fibres The noncollagenous tissue components include: Elastin which is another fibrous protein whose material properties resemble the properties of rubber. Elastin and microfibrils form the elastic fibres that are highly extensible and reversible even at high strains. not stiff Elastin fibres possess a low-modulus elastic material property, while collagen fibres show a higher-modulus viscoelastic behavior. v , stiff Collagen vs Elastin Collagen Elastin Found in skin and protective tissue. Found in the connective tissue of elastic structures. 3rd most abundant protein in the body. Less abundant. Generally white. Generally yellow. Gives strength to structures. Provides elasticity to structures. Produced until the ageing process begins. Produced mainly in the fetal period. Viscoelastic Behavior of Biological Tissues In general, the mechanical behavior of biological tissues can be described as viscoelastic. A viscoelastic model comprises: A spring to model the elastic behavior, and A dashpot to model the time dependent behavior. Biomechanics of Muscles and Joints Page 36 Skeletal Muscles Movement of human body segments is achieved as a result of forces generated by skeletal muscles which convert chemical energy into mechanical work. The skeletal muscle is composed of muscle fibres and myofibrils. Muscles exhibit viscoelastic material behaviour. Muscles are viscous in the sense that there is an internal resistance to motion. Muscle Contraction Contraction is a unique ability of the muscle tissue, which is defined as the development of tension in the muscle. In engineering mechanics, contraction implies shortening under compressive forces. In muscle mechanics, contraction can oc