Muscular system Structures, functions, and more.

Functions Muscles hold the body erect and make movement possible. Muscle movement generates nearly 85 % of our body heat. Movement adds to the flow of blood through veins as it returns to the heart. Movement moves fluid through the ducts and tubes associated with other body systems.

Types of muscle tissue Skeletal muscle: these are voluntary muscles that attach to the bones. These muscles produce movement on command from the brain. Skeletal muscles are also called: Striated (striped) muscle and voluntary muscle.

Types of muscle tissue Cardiac-Involuntary muscle of the heart. Beats bpm’s. Also know as the myocardial muscle. Cardiac muscle is specialized tissue that is like striated muscle in appearance but like smooth muscle in action. It is the contraction and relaxation of this muscle that causes the heartbeat.

Muscle tissues Smooth muscles: also know as involuntary muscle or unstriated or visceral Smooth muscle is located in the walls of internal organs, blood vessels, ducts leading from glands. Their function is to move and control the flow of fluids through this structures.

Associated structures Tendons: anchors muscle to bone. Be careful not to confuse tendons with ligaments. Remember ligaments hold bone to bone. Fascia: a fibrous membrane that covers, supports, and separates muscles Aponeurosis – very similar to a tendon. An aponeurosis attaches a muscle to other tissues.

Skeletal muscle terminology Point of origin- place at which the muscles attaches to the bone, but no movement occurs. Point of insertion- place at which muscles attaches to the bone and movement occurs.

Example of origin and insertion. Sternocleidomastiod Origins: midline at the sternum and clavicle. Insertion: at the mastoid process. These muscle allows for flexion of the neck and rotation of the head.

Characteristics of muscles Antagonistic muscle pairs- the muscles are arranged in antagonistic pairs. Meaning they work on opposition of each other. In an antagonistic pair one muscle produces movement in one direction, and the other produces movement in the opposite direction.

Range of motion Range of Motion ( ROM) is the change in joint position that is produced by muscle movement. Range of motion exercises- form of therapeutic exercises to increase strength, flexibility, and mobility.

Examples Passive ROM -

Active ROM

Contrasting muscle movements 1. Abduction- away from midline Adduction – toward the midline 2. Flexion – bending ( decreases an angle as in bending a joint. Extension – (straightening) increases the angle as in straightening a joint.

Contrasting muscle movements 4. Elevation – raises a body part. Depression – lowers a body part 5. Rotation – turns a bone on its own axis. Circumduction – turns at far end. 6. Supination – turns the palm upward or forward Pronation _ turns tha palm downward or backwards.

Contrasting muscle movements 7. Dorsiflexion – bends the foot upward Planterflexion – bends the foot downward ( pointing toes)

How muscles are named Origin and insertion Example : sternocleidomastoid; helps flex the neck. Origin begins at the midline from the sternum and clavicle. It inserts into the mastoid process.

How muscles are named For location Example: pectoralis major: pectoral means relating to chest

How muscles are named For fiber direction Examples: retus abdominis ( retus means straight) External oblique's ( oblique means slanted) Transverse abdominis ( transverse means a crosswise or straight direction)

How muscles are named For the number of divisions Examples : Biceps are formed from two divisions ( bi- meaning two) Triceps are formed from three divisions. ( tri- means three) quadriceps are formed from four divisions ( quad – meaning four)

Key word parts Bi--taxia Tri-my/o Quad--plegia -cele - tonia -desis tend/o Fasci/o tendin/o Kinesi/o Brady-

Key Terms Torticollis Atrophy Bradykinesia- Myorrhapy- Fasciotomy- Adhesion- Dystonia-

Key Terms Tenodesis- Spasm- Fasciitis- Tenoplasty- Kinesiology- Hyperkinesia- Hypokinesia- Contracture-