KIN 3309 1st Edition Lecture 7 Outline of Last Lecture I The Lower Leg II The Knee Joint III Movements of the Knee Joint IV Anatomical and Functional Characteristics V Tibiofibular Joint of the Knee VI Knee Menisci and Ligaments VII Muscles Acting at the Knee VIII Strength and Force IX Injury Potential X The Ankle and Foot XI Anatomical and Functional Characteristics of the Ankle Joint XII Movements at the Ankle XIII Pronation and Supination at the Foot XIV Strength and Forces XV Injury Potential XVI Locomotion XVII The Vertebral Column XVIII Regions of the Spine XIX Key Muscles of the Trunk XX Motion Segments of the Spine XXI Range of Motion in Individual Motion Segments Contribution to Total Movement XXII Strength and Forces at the Vertebral Joints XXIII Posture XXIV Postural Deviations XXV Stretching and Strengthening Exercises XXVI Injury Potential XXVII Disc Degeneration XXVIII Effects of Aging on the Trunk XXIX Contribution of Trunk Musculature to Sports Skills or Movements XXX Quiz Outline of Current Lecture I Review of Mathematical Fundamentals These notes represent a detailed interpretation of the professor s lecture GradeBuddy is best used as a supplement to your own notes not as a substitute II Review for Quiz 1 III Kinematics vs Kinetics IV Cardinal Planes V Stress and Strain VI Stress Strain Curve VII Ossification Modeling and Remodeling VIII Types of Muscle IX Myofibril and Sarcomere X Motor Unit XI Characteristics of Muscle XII Role of Muscle XIII Net Muscle Actions XIV Force Length Relationship XV Recruitment and Rate Coding XVI Reflex XVII Proprioceptive Receptors XVIII EMG XIX The Shoulder Complex XX The Lower Leg XXI The Knee Joint XXII The Vertebral Column XXIII Key Muscles XXIV Effects of Aging on the Trunk Current Lecture Will provide scantrons for all quizzes and test 80 90 are from the quiz questions at the end of class I Review of Mathematical Fundamentals II Review for Quiz 1 a Cover Lecture 1 7 b Location GAR 205 c Time 4 5 30 III Kinematics vs Kinetics a Kinematics i Examines spatial space and temporal time characteristics of motion 1 Position displacement velocity and acceleration ii Example How fast the is moving how high it goes or how far it goes iii The force causing the motion are not considered b Kinetics i Examines forces torques that cause motion 1 Magnitude direction line of action point of application c Force is what distinguishes the two from each other IV Cardinal Planes a Sagittal i Left and right halves ii Mediolateral axis b Frontal coronal i Front and back halves ii Anteroposterior axis c Transvers horizontal i Upper and lower halves ii Longitudinal axis V Stress and Strain a Stress i force applied per unit area ii area is usually a cross sectional area iii Measured in N m2 b Strain i deformation caused by applied stress ii Dimensionless 1 Often put in terms of change in length VI Stress Strain Curve a Yield point i Up to yield point structure is in its elastic region ii Past the yield point is the structures plastic region b Failure i If the applied force continues past the plastic region the tissue will eventually fail VII Ossification Modeling and Remodeling a Ossification i Is the formation of bone by the activity of the osteoblasts and osteoclasts b Modeling i Occurs during growth to create a new bone c Remodeling i The bone matrix is constantly being removed and replaced 1 Osteoblasts build bone deposition 2 Osteoclasts convert consume bone resorption VIII Types of Muscle a Skeletal Muscle i Is associated with the bony skeleton and consists of large cells that bear striations and are controlled voluntarily b Cardiac Muscle i Occurs only in the heart and consists of small cells that are striated and under involuntary control c Smooth Muscle i Is found in the walls of hollow organs and consists of small elongated cells that are not striated and are under involuntary control IX Myofibril and Sarcomere a Contractile element of muscle fiber b Contain sarcomeres functional unit of skeletal muscle X Motor Unit a A motor neuron and all the muscle fibers it innervates all or none principle b Smallest unit of the neuromuscular system c The number of muscle fibers in a motor unit innervated by 1 motor neuron varies i Gastrocnemius 1 2 000 muscle fibers per motor neuron ii Extraocular muscles 1 10 muscle fibers per motor neuron d Ratio of muscle fibers to motor neurons i Affects the precision of movement XI Characteristics of Muscle a Irritability i Ability to respond to stimulation b Contractility i Ability to shorten ii Unique to muscle tissue c Extensibility i Ability to stretch lengthen beyond the resting length d Elasticity i Ability to return to resting length XII Role of Muscle a Prime mover b Assistant mover c Agonist d Antagonist e Stabilizer f Neutralizer XIII Net Muscle Actions a Isometric i Tension increases to the muscles capacity but the muscle neither shortens nor lengthens b Isotonic i The muscle changes in length decreasing the angle of the joint and moves the load ii Concentric 1 The muscle shortens to cause movement iii Eccentric 1 The muscle contracts as it lengthens to resist control or slow down movement and maximal force is generated XIV Force Length Relationship a b muscle can create the greatest tension at b XV Recruitment and Rate Coding a Recruitment i Tension generated is determined by the size and number of motor units recruited b Frequency coding i Also called rate coding ii High frequency can induce high tension production XVI Reflex a Myotactic reflex i Also called stretch reflex ii Causes contraction of a muscle being stretched b Flexor Reflex i Initiated by painful stimulus ii Causes quick withdrawal flexion of the limb c Cutaneous reflex i Causes relaxation of muscle with heat or massage XVII Proprioceptive Receptors a Sensory receptors in the musculoskeletal system b Muscle Spindle i Monitors muscle stretch QQ ii Intrafusal fibers c Golgi tendon organ i Monitors muscle force or tension ii Connected directly to extrafusal fibers XVIII EMG a Technique for evaluating and recording the electrical activity produced by skeletal muscles b Physiological basis i Muscle contraction due to a change in the relative sliding of thread like molecules or filaments 1 Actin and myosin ii Filament sliding triggered by electrical phenomenon Action Potential XIX The Shoulder Complex a Sternoclavicular i Articulation between the sternum and clavicle b Acromioclavicular i Articulation between the acromion process of scapula