Clinical Kinesiology and Anatomy - Chapter 1
Definition and Scope of Kinesiology
Kinesiology is defined as the scientific study of human movement.
It represents the clinical application of four foundational sciences:
Anatomy
Physiology
Physics
Mechanics
The purpose of studying kinesiology in a clinical context is to understand the characteristics of typical or normal movement. This understanding allows practitioners to:
Effectively select appropriate treatments aimed at the development of physical therapy patient management.
Achieve maximum functional outcomes for the patient.
Mechanics and Biomechanics
Mechanics is the branch of physics that involves the study of forces exerted on objects.
Biomechanics involves the application of mechanical principles specifically to the study of human movement. It is divided into two main categories:
Kinematics: This branch describes the motion of a body without regard to the forces or torques that cause the motion. It encompasses both arthrokinematics and osteokinematics.
Kinetics: This branch describes the effect of forces and torques acting on the body.
Movement Classifications: Arthrokinematics and Osteokinematics
Arthrokinematic Motion:
Refers to movements occurring specifically between joint surfaces.
The three primary types of arthrokinematic motion are:
Roll
Spin
Glide (also referred to as slide)
Osteokinematic Motion:
Refers to the movement of limbs or body segments through space as they move about a joint.
Examples of these motions include:
Flexion and Extension
Abduction and Adduction
Medial Rotation and Lateral Rotation
Basic Principles of Joint and Muscle Function
Kinesiology relies on three fundamental principles regarding muscles and joints:
Understanding the specific movements that a particular joint allows.
Recognizing that a muscle must span a specific side of a joint surface in order to cause a specific movement.
Analyzing a muscle's line of pull relative to the joint it crosses (e.g., the elbow joint).
The Anatomical Position
The anatomical position is defined as an erect posture characterized by:
Body weight distributed evenly.
Eyes level and facing directly forward.
Feet parallel to each other and positioned slightly apart.
Arms resting at the sides with the palms of the hands facing forward.
Importance of the Anatomical Position:
It serves as the neutral starting position from which all limb segment movements are defined and measured.
Descriptive and Directional Terminology
The following terms are used to describe the location and relationship of body parts:
Superior: Toward the head or upper part of a structure.
Inferior: Away from the head or toward the lower part of a structure.
Anterior (Ventral): Toward the front of the body.
Posterior (Dorsal): Toward the back of the body.
Medial: Toward the midline of the body.
Lateral: Away from the midline of the body.
Proximal: Closer to the trunk or the point of origin.
Distal: Farther from the trunk or the point of origin.
Cranial: Toward the head.
Caudal: Toward the tail or inferior end of the body.
Segments of the Human Body
The body is divided into several primary segments and regions:
Head and Neck.
Trunk: Comprised of the Thorax and the Abdomen.
Upper Extremities: Comprised of the Arm, Forearm, and Hand.
Lower Extremities: Comprised of the Thigh, Leg, and Foot.
Kinetic Chain Systems
A kinetic chain consists of a series of connected rigid links, such as limb segments, which influence the type and nature of movements.
There are two primary types of kinetic chains:
Closed Kinetic Chain (CKC): In this system, the distal segment is fixed (stationary), while the proximal segment is free to move.
Open Kinetic Chain (OKC): In this system, the distal segment is free to move, while the proximal segment remains fixed.
Planes and Axes of Motion
Movement is categorized by the plane in which it occurs and the axis around which it rotates.
Planes of the Body:
Sagittal Plane: Passes vertically from anterior to posterior, dividing the body into right and left halves.
Frontal Plane: Passes vertically from side to side, dividing the body into anterior and posterior portions.
Horizontal (Transverse) Plane: Passes horizontally, dividing the body into superior and inferior portions.
Axes of the Body:
Sagittal Axis: Passes through a joint from anterior to posterior.
Frontal Axis: Passes through a joint from side to side.
Vertical Axis: Passes through a joint from superior to inferior.
Relationship Between Planes and Axes:
Flexion and Extension: Occur in the sagittal plane about a frontal axis.
Abduction and Adduction: Occur in the frontal plane about a sagittal axis.
Medial and Lateral Rotation: Occur in the horizontal plane about a vertical axis.
Degrees of Freedom
Degrees of freedom refer to the number of planes within which a specific joint can move.
Classifications:
Uniaxial Joint: Movement occurs in plane about axis; it possesses one degree of freedom.
Biaxial Joint: Movement occurs in planes about axes; it possesses two degrees of freedom.
Triaxial Joint: Movement occurs in planes about axes; it possesses three degrees of freedom.
Examples:
The Elbow joint has degree of freedom.
The Wrist joint has degrees of freedom.
The Shoulder and Hip joints each have degrees of freedom.
Specific Osteokinematic Movements
These movements can be performed as Active Range of Motion (AROM) or Passive Range of Motion (PROM) and are described in relation to the anatomical position:
Flexion and Extension
Abduction and Adduction
Horizontal Abduction and Horizontal Adduction
Medial (Internal) Rotation and Lateral (External) Rotation
Dorsiflexion and Plantarflexion
Radial Deviation and Ulnar Deviation
Lateral Flexion
Supination and Pronation
Inversion and Eversion
Circumduction
Opposition and Reposition
Scapular Retraction, Elevation, and Depression
Range of Motion (ROM)
Range of Motion is defined as the total amount of motion a joint is capable of moving in any of its possible directions.
Measurement and Standards:
ROM is measured using a tool called a goniometer.
The anatomical position is utilized as the degree point (zero point) for these measurements.