Musculoskeletal System - Unit 1 PDF

UNIT 1:MUSCULO-SKELETAL SYSTEM LEARNING OBJECTIVES At the end of the unit the students should: 1. Identify the bones and muscles in the body, 2. Analyze which specific muscle/s produce specific movement at the joints, and 3. Relates Musculo -skeletal activities to production of movement patte...

UNIT 1:MUSCULO-SKELETAL SYSTEM LEARNING OBJECTIVES At the end of the unit the students should: 1. Identify the bones and muscles in the body, 2. Analyze which specific muscle/s produce specific movement at the joints, and 3. Relates Musculo -skeletal activities to production of movement patterns. THE SKELETAL SYSTEM The skeletal system is the structure that gives our shape, provides protection for our internal organs and offers a support framework for the attachment of muscles therefore facilitating movement. It has 2 types- appendicular and axial. Shoulder girdle & upper limbs Skull Thoracic girdle Pelvic girdle & upper limbs Vertebral Column TYPES OF BONE AND CARTILAGE Bone is made of collagen fibers filled with minerals, mainly calcium salts. JOINTS Joints are links between the bones of the skeleton. They act to allow movement but also work to stabilize areas of the body. MOVEMENTS OF SYNOVIAL JOINTS The movements at any joint are possible because of its structure and the skeletal muscles that contract to pull the bone into a different position. Every skeletal muscle is attached to bone at a minimum of two points on opposite sides of a joint. When the muscle contracts across a joint, one point of attachment is pulled towards the other, causing joint movement. FLEXION AND EXTENSION Flexion of a joint makes a body part move in a forward direction from the anatomical position. Extension of a joint makes a body part move in a backwards direction. HORIZONTAL FLEXION AND HORIZONTAL EXTENSION Horizontal flexion occurs when the shoulder is already flexed with the arm parallel to the ground and the shoulder joint moves towards the center of the body. Horizontal extension occurs when the shoulder joint with the arm parallel to the ground moves away from the middle of the body. ABDUCTION AND ADDUCTION Abduction of a joint makes a body part move away from the midline of the body in the anatomical position. Adduction of a joint makes a body part move towards the midline of the body. ROTATION Rotation of a joint is when a body part turns about its long axis from the anatomical position. CIRCUMDUCTION Circumduction of a joint makes a body part move from the anatomical position, describing a cone shape. The joint performing circumduction stays still while the furthest end of the body part moves in a circle. PRONATION AND SUPINATION Pronation and supination are anatomical terms unique to the radio-ulnar joint and are separate terms to describe rotation of the forearm. In the anatomical position the radio-ulnar joint is supinated. LATERAL FLEXION Lateral flexion is an anatomical term unique to the spine. It involves bending the spine sideways DORSILFLEXION AND PLANTAR FLEXION Dorsiflexion and plantar flexion are anatomical terms unique to the ankle joint. Dorsiflexion of the ankle joint makes the foot move towards the shin as when you walk on your heels. Plantar flexion of the ankle joint makes the foot move away from the shin as when you walk on your tiptoes. Joint Joint type Joint movement Left shoulder Ball & socket Flexion Right wrist Condyloid Extension Right knee Hinge Extension The Muscular System The Muscular System Muscles pull the bone to produce movement. Movement of muscle and bones goes in pairs. Antagonistic muscle action- whatever one muscle can do, there is another muscle that can undo it to return the body to the original position. Agonist muscle Antagonist muscle -Prime movers -Opposite action -Muscles that pull -Stabilize joint movement -Shortens during movement -Lengthens during movement  Movement in the muscle Agonist muscle -Prime movers Biceps Triceps Hamstrings Quadriceps -Muscles that pull -Shortens during movement Antagonist muscle -Opposite action Triceps Biceps Quadriceps Hamstrings -Stabilize joint movement -Lengthened during movement  Rotator cuff Infraspinatus subscapularis