 To identify the types of muscles
 Understand terms related to muscles
 To know how are the muscles named

 Skeletal:striated, and voluntary.
 Smooth:nonstiated, and involuntary.
 Cardiac:striated, and involuntary.

 Endomysium : a delicate connective tissue sheath surrounds muscle fibre.
 Perimysium : a coarser fibrous membrane surrounds several sheathed muscle fibers to form bundle of fibers called a fascicle.
 Epimysium : a tougher overcoat of connective tissue surrounds many fascicles.

 The epimysia blend into the strong, cordlike tendons, or into sheet-like aponeurosis .
 Function :
1-Attaching the muscle to bone….
2-Providing durability
3-Conserving space

 Skeletal muscles cause the skeleton to move at joints
 They are attached to skeleton by tendons.
 Tendons transmit muscle force to the bone.
 Tendons are made of collagen fibres & are very strong & stiff

 Providing movement
 Maintaining posture
 Stabilizing joint
 Generating heat



 Functions of Skeletal
Muscle
– Produce Movement
– Maintain posture
– Stabilize joints
– Generate Heat
Sites of Muscle
Attachment
– Bones
– Cartilage
– Connective tissue coverings

Muscle Fibers blend into a connective tissue attachment
– Tendon—cordlike structure
– Aponeurosis—sheet-like structure
Properties of Muscle
– Irritability – ability to receive and respond to a stimulus
– Contractibility – ability to shorten when an adequate stimulus is received
– Extensibility – ability to lengthen when an adequate stimulus is received
– Elasticity – ability to return to normal shape

 Muscles:
Are responsible for almost all the movements in animals

 Origin : is the point where the muscle is attached to immovable or less movable bone.
 Insertion : is the point where the muscle attached to movable bone.

 Prime mover : the muscle that has the major responsibility for causing a movement.
 Antagonist : the muscle that reverse a movement.

 Muscles are either contracted or relaxed
 When contracted the muscle exerts a pulling force, causing it to shorten
 Since muscles can only pull (not push), they work in pairs called antagonistic muscles
 The muscle that bends the joint is called the flexor muscle
 The muscle that straightens the joint is called the extensor muscle

 The best known example of antagonistic muscles are the biceps & triceps muscles
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
Direction of the muscle fibers: Orbicularis oris, Occuli
 Relative size of the muscle: Gluteus maximus, medius, minimus…Major, minor.
 Location of the muscle:Obturator internus
 Number of the origin:Biceps, Triceps
 Location of the muscle’s origin and insertion : Occipitofrontalis
 Shape of the muscle:Deltoid
 Action of the muscle:Pronator Quadratus

 Flexion&extension in sagittal plane angle of the joint

 Rotation
It is the movement of a bone around its long axis atlas around the dens of axis

 Abduction &adduction moving the limb away or toward the midline of the body

 Circumduction is a combination of flexion,extension,abduction and adduction

 Dosiflexion&planter flexion
 Inversion and evasion
 Supination and pronation
 opposition

 Facial Muscles (Frontalis, Orbicularis oculi
Orbicularis oris, Buccinator,Zygomaticus) .
 Chewing Muscle (Buccinator,Masseter,
Temporalis).

 Frontalis : It covers the frontal bone
 It raise the eyebrows
 It wrinkle the forehead
 Orbicularis oculi : It has fibres that run in circles around the eyes.
 It closes the eyes, squint, blink.

 Orbicularis oris : it is a circular muscle of the lips.
 It closes the mouth
 It protrude the lips
 Buccinator : it runs horizontally across the cheek and inserts into orbicularis oris.
 It flatten the cheek.

 Zygomaticus
 It extends from the corner of the mouth to the cheekbone.

 Buccinator
 Masseter : it covers the angle of lower jaw
 It closes the jaw by elevating the mandible
 Temporalis : it is a fan shaped muscle overlying temporal bone
 It is synergist of the masseter in closing the jaw.

 Sternocleidomastoid : it is a paired muscles with two headed muscles, one from each side of the neck.
 platysma

 Anterior muscles
 Muscles of the abdominal wall
 Posterior muscles (Post. Antigravity muscles)

 Anterior muscles :
Pectoralis major : a large fan shaped muscle covering the upper part of the chest.
It adduct and flex the arm. It forms the anterior wall of the axilla
Intercostal muscles

 Muscles of the abdominal wall :
 Rectus abdominis
 External oblique
 Internal oblique
 Transversus abdominis

 Posterior muscles :
Trapezius : It is the most superficial muscles of posterior neck and upper trunk.
Diamond –shaped.
Extend the head &antagonist sternocleidomastoid.
Also,it can elevate, depress, adduct , and stabilize the scapula.

 Latissmus Dorsi
Large, flat muscle pair that cover the lower back.
Extends and adducts the humerus.
Erector spinae
Prime mover of back extention
Paired muscles
Deep muscles of the back.
Spasm of these muscles lead to lower back pain.

 Deltoid
Fleshy, triangle-shaped muscles
Favorite injection
Prime movers of arm abduction.

 The first group include muscles that arise from the shoulder girdle and cross the shoulder joint to insert into the humerus
(pectoralis major, latissimus dorsi, and deltoid).

 The second group causes movement at the elbow joint (Biceps brachii,brachialis,brachioradialis, and triceps brachii)

 The third group causes movement at the wrist joint (flexor carpi and flexor digitorum)
(extensor carpi and extensor digitorum)

 Muscles causing movement at the hip joint
 Muscles causing movement at the knee joint
 Muscles causing movement at the ankle and foot joint

 Muscles causing movement at the hip joint
(gluteus maximus,gluteus medius,illiopsoas
,adductor muscles)

 Muscles causing movement at the knee joint
(hamstring group,sartorius ,quadriceps group)

 Muscles causing movement at the ankle and foot joint (tibialis anterior,extensor digitorum longus,fibularis muscles,gastrocnemius,soles)