I. Basic Concepts in Kinesiology. Kinematics

I. BASIC CONCEPTS IN KINESIOLOGY: KINEMATICS BRIEF HISTORY KINESIOLOGY ● study of human motion = art + science ● appreciation of beauty of human movement + understanding of scientific principles that provide movement ● theories and principles from: ○ Biomechanics: The application of the principles of mechanics to the living human body ○ Anatomy: The study of the structure and organization of living organisms, focusing on the physical makeup of their bodies ○ Physiology: The study of the functions and processes of living organisms and their parts, explaining how the body's systems work. ○ Mechanics: The branch of physics that deals with the behavior of physical bodies when subjected to forces or ● displacements, and the effects of these on their motion. ○ Anthropology: The study of humans, their societies, cultures, and development over time, encompassing both biological and social aspects ○ Physics: The science that studies matter, energy, and the fundamental forces of nature, exploring how they interact and govern the universe CLINICAL KINESIOLOGY: application of kinesiology to environments of the health care professional ○ PURPOSE: To understand the movement & the forces acting on the human body learn how to manipulate these forces to prevent injury, restore function, and provide optimal human performance KINES: STUDY OF HUMAN MOVEMENT ● ● Kinetics: forces Kinematics: motion (types, direction, quantity) ○ Osteokinematics: movements of bony partners/segments that make up a joint; flex, ext, abd, add ○ Arthrokinematics: small movements occuring within the joint & between joint surfaces; gliding, rolling, spinning PLANES OF MOTION: CARDINAL PLANES NAMING MOVEMENTS AT JOINTS ● ● ● ● 3 primary planes that divide the body and guide its movements flat, 2D surfaces along which movement occurs help describe how an object moves in relation to its orientation We name joints by using the names of the 2 bones that form the joint, typically by naming the proximal bone first ○ eg: RU, AA, SI joints AXES OF MOTION ● ● ● An imaginary line around which the body or its segments rotate during movement Axes around which movement occurs Perpendicular to the planes of motion SPECIAL CASES: Thumb ● Normal position is rotated 90° from the plane of the hand ● Motions of flexion and extension occur in the frontal plane rather than the sagittal plane ● Abduction and adduction occur in the sagittal plane rather than the frontal plane Forearm: Pron & Sup ● As the forearm rotates, the motion no longer occurs on a longitudinal axis but on an anterior-posterior axis Hip: Med & Lat Rotation ● As the flexed hip rotates, the motion no longer occurs on a longitudinal axis but on an anterior-posterior axis TYPES OF MOTION ● The body and its segments move one of two ways: motion is either translatory or rotary ● Linear + Rotatory movements = FUNCTIONAL MOTION ● Translatory ○ Linear ○ occurs along or parallel to an axis ■ Rectilinear ● movement in a straight line ■ Curvilinear ● movement in a curved path Rotatory ○ Angular ○ occurs in a circle around an axis or a pivot point, ○ so every point on the object attached to the axis follows the arc of a circle ○ Axis of rotation ■ pivot point for this angular or rotary motion ● DEGREES OF FREEDOM ● ● Number of planes within which a joint moves Given that the body and its segments move in: 3 planes of motion, degrees of freedom (maximal) at 3° ○ maximal degrees of freedom = maximum number of different ways a body part can move A. UNIaxial a. joints that move in 1 plane around 1 axis b. 2 types: i. Hinge ii. Pivot B. BIaxial a. joints that move in 2 planes around 2 axes b. 3 types: i. Condyloid ii. Ellipsoidal iii. Saddle C. TRIaxial a. Joints that move in 3 planes around 3 axes b. Ball-and-socket joints UNIaxial Hinge ● ● ● ● Pivot ● ● ● ● ● Saddle convex + concave surfaces Interphalangeal (IP) Humeroulnar (Elbow Joint) Tibiofemoral & Patellofemoral (Knee Joint) cylindrical or conical synovial / rotary joints type of synovial joint Atlantoaxial (C1 and C2) ○ rotation of the head from side to side, shaking the head "no” Radioulnar Joint BIaxial ● ● ● have greater ROM perpendicular concave + convex surfaces Carpometacarpal (CMC) TRIaxial Ball-and-socket ● spherical ball + ● concave cup ● Glenohumeral (Shoulder joint) ● Pelvic Acetabulum & Femoral Head (Hip joint) CIRCUMDUCTION VS ROTATION ○ ellipsoid joints are essentially a subtype of condyloid joints with a more specific shape. Condyloid ● oval-shaped condyle + elliptical cavity ● spherical convex + shallow concave ● MCP + MTP Ellipsoid Joints ● ovoid condyle (elongated) + elliptical cavity ● flattened convex + fairly deep concave ● Atlanto-occipital ● Radiocarpal (wrist) CIRCUMDUCTION ROTATION - circular or conical movement -sequential combination of: flex, ext, abd & add -turning or spinning around a central point or axis -without changing the position of the joint itself from side to side