Frontal Belly (Epicranius) Occipital Belly (Epicranius) Orbicularis Oculi Orbicularis Oris Zygomaticus minor Zygomaticus major Buccinator Facial Expression Origin- stays still Raises eyebrows Galea aponeurotica Insertion- moves Skin of eyebrows Pulls scalp back Galea aponeurotica Occipital bones Masseter- in front of ear Temporalis Closes eyes Frontal bones Closes lips Maxilla Smile Zygomatic bone Smile Zygomatic bone Compresses cheeks Mandible The Jaw Closes jaw Zygomatic arch Closes jaw Temporal fossa Platysma The Neck Tenses skin of neck Deltoid Sternocleidomastoid Flexion of neck forward Medial of clavicle Thorax, Shoulder, Abdominal Wall Inserts of eyelid tissue Encircles mouth Skin at corner of mouth Skin at corner of mouth Orbicularis oris Angle of mandible Coronoid process of mandible Lower margin of mandible Mastoid process of temporal bone
Origin Clavicle Pectoralis Minor Prime mover of arm flexion, rotates arm Draws forward Serratus Anterior Rotate Lateral aspects of ribs Deltoid Acromion External Intercostals Prime mover of arm abduction Elevate rib cage Internal Intercostals Depress rib cage Diaphragm Prime mover of inspiration, flattens on contraction Rotate vertebral column Compress abdominal wall Compress abdominal wall Compress abdominal contents Superior border of rib below Lumbar vertebrae Pectoralis Major Rectus Abdominis External Obliques Internal Obliques Transversus Abdominis Anterior surface of ribs Inferior border of rib Insertion Intertubercular sulcus in Coracoid process Anterior surface of Deltoid tuberosity of Superior border of rib below Inferior border of rib above Central tendon Pubic crest Anterior surface of 8 ribs Iliac crest Xiphoid process Pubic crest Iliac crest Pubic crest Pubic crest
Trapezius Latissimus Dorsi Rhomboids Minor Rhomboids Major Infraspinatus Supraspinatus Teres Minor Teres Major Human Trunk- the Back Origin Rotates Thoracic vertebrae Prime mover of arm Lumbar vertebrae extension Stabilize Spinous processpointed tip of vertebrae Stabilize Spinous process s of Scapula (rotator cuff) Lateral rotation of Infraspinous fossa of Lateral rotation of Supraspinous fossa of Lateral rotation of Lateral margin of Rotation of Inferior angle of Humerus s act on Forearm Insertion Acromion of Floor of Medial border of Medial border of Greater tubercle of Greater tubercle Greater tubercle Intertubercular sulcus of
Triceps Brachii Forearm extensor Origin Inferior of glenoid cavity Biceps Brachii- Flexion of elbow Coracoid process Supraglenoid tubercle Distal of anterior Distal end of muscle closer to body Brachialis Flexion of forearm Brachioradialis Synergist (helper) in forearm flexion Pronator Teres-inner elbow Flexor Carpi Radialis Flexor Carpi Ulnaris Palmaris Longus 4. Extensor carpi radialis Longus 3. Extensor carpi radialis Brevis thumb side 2. Extensor Digitorum 1.Extensor carpi ulnaris Supinator on outside edge of elbow Humerus s act on Hands/ Fingers Pronate forearm Medial epicondyle of Flexor of wrist Medial epicondyle Flexor of wrist Tenses skin Extend wrist Insertion Olecranon processopposite end of ulna head Radial tuberosity- bump near the head Coronoid process- lower than olecranon of ulna Styloid process of radius- opposite end of head Midshaft of radius Base of metacarpals Medial epicondyle Medial epicondyle Lateral supracondylar ridge of Lateral epicondyle of Base of metacarpal 5 Skin of palm Base of metacarpal 2 Prime mover of finger extension Extend wrist Lateral epicondyle Distal phalanges Lateral epicondyle Base of metacarpal 5 Acts w/ biceps brachii to supinate forearm Lateral epicondyle Proximal end of radius Extend wrist Base of metacarpal 3 Radial head by the elbow, ulna head at other end by wrist Pronator teres touches flexor carpi radialis Under forearm: (thumb side) Brachioradialis- Flexor Carpi Radialis- Palmaris Longus- Flexor Carpi Ulnaris (pinky side) Above Forearm: (pinky side) Flexor Carpi Ulnaris- Extensor Carpi Ulnaris- Extensor Digitorum- extensor carpi radialis longus
Thigh and Leg
Iliopsoas Flex thigh Origin Iliac crest Sartorius Flex thigh Anterior superior iliac spine Ischial tuberosity Pubis Flex thigh Adductor Magnus Flex thigh Adductor Longusabove the magnus Gracilis- long muscle, Adducts thigh inner thigh Rectus Femorismain muscle on anterior leg Vastus Lateralis Vastus Medialis Vastus Intermedius Tensor Fasciae Latae Biceps Femoris Semitendinosus Semimembranous Gluteus Maximus Body of pubis Insertion Lesser trochanter of femur proximal tibia Linea aspera Linea aspera Medial of tibia Quadriceps (front of thigh) Extend knee Anterior inferior iliac spine Tibial tuberosity Extend knee Extend knee Extend knee Steadies trunk Tibial tuberosity Tibial tuberosity Tibial tuberosity Iliotibial tract Greater trochanter Linea aspera Lateral surface of femur Anterior aspect of iliac crest Hamstrings (back of thigh) Extend thigh Linea aspera Extend thigh Ischial tuberosity Extend thigh Ischial tuberosity Butt Powerful thigh extensor Coccyx and sacrum Head of fibula Upper tibial shaft Medial condyle of tibia Gluteal tuberosityfemur Medially rotates thigh Upper lateral surface of Greater trochanter of Gluteus Medius ilium femur Thigh Anterior: (left to right) Vastus Lateralis- Vastus Intermedius- Vastus Medialis [Rectus Femoris on top of V. Inter.]
Tibialis anterior Tibialis posterior EXTENSOR digitorum longus FLEXOR digitorum longus Gastrocnemius Soleus Popliteus Feet and Ankle Origin Prime mover of Lateral condyle- femur dorsiflexion Prime mover of foot Superior of tibia inversion Prime mover of toe Lateral condyle of tibia extension Flexes toes Posterior of tibia Plantar flexes foot (move foot up and down) Plantar flexion Flexes leg Insertion Metatarsal 1 Several tarsals Distal phalanges Distal phalanges Medial condyle of femur Calcaneus (heel bone) Proximal portion of tibia Lateral condyle of femur Calcaneus Proximal tibia
All muscles exert their force by pulling between at least two points of attachment. The movement that results from contraction is called the action of the muscle. Typically, one attachment remains stationary and is called the origin and the other attachment moves and is called the insertion. Almost all muscles cross at least one joint (moveable connection between two bones) and cause an action across that joint. The type of movement that results depends upon the nature of the joint. Common types of movement that result from muscle contraction include: Flexion A movement that decreases the angle between two bones at the joint. Extension A movement that increases the angle between two bones at the joint. However, if the angle goes past 180o (a straight line) in the direction opposite flexion the movement is called hyperextension. Rotation Rotation is a movement that results in movement of one bone around its longitudinal axis. Abduction A movement that results in the part moving away from the midline.
Adduction A movement that results in the part moving toward the midline. Special types of movement occur at particular joints and include: Dorsiflexion and plantar flexion These movements only apply to movements of the foot at the ankle joint. Dorsiflexion is when the foot is raised as when you dig in your heels. Plantar flexion is when you lower your foot as when you lift yourself onto the balls of your feet. Inversion and eversion These movements also apply only to the feet. Inversion is when you turn your feet inward so that your soles are facing one another. Eversion is when you turn your feet outward so that your soles are facing laterally. Supination and pronation These movements apply to the forearm. Pronation is rotation of the radius across the ulna that results is your palms facing backwards. Supination is movement in the opposite direction that uncrosses the radius from the ulna to cause the palms to face forward. Opposition This movement enables us to be skillful tool users. Opposition is the movement of the tip of the thumb that enables it to touch the tips of the other fingers. Chapter 12- anatomy of Skeletal Sarcolemma-plasma membrane of skeletal cells Myofibrils- longitudinally arranged, fill sarcoplasm, push nuclei peripherally Myofilaments- smaller threadlike structures make up the myofibrils - Composed of contractile proteins: actin and myosin (slide past each other during muscle activityshorten or contract muscle cells) Sarcomeres- actual contractile units of muscles extending from Z disc to next Z disc (middle of I band) Transverse tubule (T tubule)- formed by the sarcolemma indents in muscle cell (junction of A and I bands) - Tubules run deep btwn cross channels or terminal cisternae - Sarcoplasmic Reticulum- elaborate smooth endoplasmic reticulum - Triads- regions where SR terminal cisternae abut a T tubule on each side Endomysium- delicate areolar CT sheath wrapping muscle fiber Perimysium- collagenic membrane wrapping sheathed muscle fibers Fascicle- a bundle of fibers formed by perimysium wrapping the fibers together Epimysium- overcoat of dense CT which sheathes entire muscle Deep Fascia- coarse sheets of dense CT that bind muscle into function groups (tendons or aponeuroses) Aponeuroses- sheetlike functional group which attaches muscles to each other or indirectly to bones Insertion- movable attachment Origin- fixed/ immovable attachment Tendons fx- provide durability and conserve space Neuromuscular junction- junction btwn nerve fiber (Axon) and muscle cell - Neuron and muscle fiber membranes don t touch, are separated by small fluid filled gap called the synaptic cleft Triceps brachii- forearm extension- INFERIOR OF GLENOID CAVITY olecranon process of ulna Biceps brachii- elbow flexion- supraglenoid tubercle and coracoid process- radial tuberosity Brachialis- forearm flexion- distal end of -coronoid process ulna Brachioradialis- synergist arm flexion- distal end of - styloid process radius