click below
click below
Normal Size Small Size show me how
Muscles [Complete]
Question | Answer |
---|---|
Frontalis | Origin: Aponeurosis Insertion: Skin of eyebrow Action: Elevates eyebrows; Wrinkles forehead |
Orbicularis oculi | Origin: Frontal & maxillary bones Insertion: Tissue of eyelids Action: Closes eyes as in blinking |
Buccinator | Origin: Maxilla & mandible Insertion: Orbicularis oris Action: Compresses cheeks inward (whistling and sucking) |
Zygomaticus | Origin: Zygomatic bone Insertion: Skin & muscle at corner of mouth Action: Raises corners of mouth (smiling) |
Orbicularis oris | Origin: Maxilla & mandible Insertion: Skin & muscle around mouth Action: Puckers & closes the lips |
Temporalis | Origin: Temporal bone Insertion: Mandible (coronoid process) Action: Elevates mandible |
Masseter | Origin: Zygomatic arch Insertion: Mandible (ramus) Action: Elevates mandible |
Sternocleidomastoid | Origin: Sternum (manubrium); Clavicle Insertion: Temporal bone (mastoid process) Action: Rotates the head to the opposite side (one); Flexes head (both) |
Trapezius | Origin: Occipital bone; Thoracic vertebrae Insertion: Clavicle; Scapula (spine & acromion process) Action: Elevates & adducts scapula; Extends neck |
Levator scapulae | Origin: Vertebrae (upper cervical) Insertion: Superior scapula Action: Elevates & adducts scapula at superior angle |
Rhomboid major & minor | Origin: Vertebrae (C7-T5) Insertion: Scapula (medial border) Action: Adducts scapula |
Pectoralis minor | Origin: Ribs (3-5) Insertion: Scapula (coracoid process) Action: Oulls scapula downward & forward (abduct) |
Serratus anterior | Origin: Ribs (upper 8) Insertion: Scapula (anterior vertebral border) Action: Pulls scapula against the chest wall |
Supraspinatus | Origin: Scapula (supraspinous fossa) Insertion: Humerus (greater tubercle) Action: Hold head of humerus stable in glenoid cavity; Abduction of humerus (30°) |
Infraspinatus | Origin: Scapula (infraspinous fossa) Insertion: Humerus (greater tubercle) Action: Hold head of humerus stable in glenoid cavity; Lateral rotation & adduction of humerus |
Teres minor | Origin: Scapula (axillary border) Insertion: Humerus (greater tubercle) Action: Hold head of humerus stable in glenoid cavity; Lateral rotation of humerus |
Subscapularis | Origin: Scapula (subscapular fossa) Insertion: Humerus (lesser tubercle) Action: Hold head of humerus stable in glenoid cavity; Medial rotation |
Pectoralis major | Origin: Clavicle, sternum & ribs (1-6) Insertion: Humerus (intertubercular groove) Action: Adducts, flexes & medially rotates humerus at shoulder joint |
Deltoid | Origin: Lateral clavicle; scapula (spine & acromion process) Insertion: Humerus (deltoid tuberosity) Action: Abducts, flexes & medially rotates humerus at shoulder joint |
Coracobrachialis | Origin: Scapula (coracoid process) Insertion: Humerus (shaft) Action: Adducts & flexes humerus at shoulder joint (synergist to pectoralis major) |
Latissimus dorsi | Origin: Vertebrae (lumbodorsal fascia); Iliac crest & ribs (lower 4) Insertion: Humerus (intertubercular groove) Action: Adducts, extends & medially rotates humerus at shoulder joint |
Teres major | Origin: Scapula (inferior border & lateral border) Insertion: Humerus (intertubercular groove) Action: Adducts, extends & medially rotates humerus at shoulder joint (synergist to latissimus dorsi) |
Biceps brachii | Origin: Short head - Scapula (coracoid process); Long head - Scapula (supraglenoid tubercle) Insertion: Radius (radial tuberosity) Action: Flexes forearm at elbow (synergist to brachiallis); Supinates forearm |
Barchialis | Origin: Humerus (anterior shaft) Insertion: Ulna (coronoid process) Action: Flexes forearm at elbow |
Brachioradialis | Origin: Humerus (lateral supracondylar ridge) Insertion: Radius (styloid process) Action: Flexes forearm at elbow (synergist to biceps brachii) |
Triceps brachii (long, lateral, medial) | Origin: Scapula (infraglenoid tubercle); Posterior proximal humerus Insertion: Ulna (olecranon process) Action: Extends forearm at elbow |
Flexor carpi muscles (radialis, ulnaris) | Origin: Humerus (medial epicondyle) Insertion: Metacarpals Action: Flex hand at wrist |
Flexor digitorum muscles (superficialis, profundus, flexor pollicis) | Origin: Distal humerus; Proximal radius or ulna Insertion: Middle or distal phalanges Action: Flex the fingers |
Extensor carpi muscles (radialis, ulnaris) | Origin: Distal, lateral humerus Insertion: Metacarpals Action: Extend hand at wrist |
Extensor digitorum | Origin: Humerus (lateral epicondyle) Insertion: Distal phalanges Action: Extends the hands & fingers |
Rectus abdominis | Origin: Pubic bone (crest & symphysis) Insertion: Sternum (xiphoid process); Ribs (costal cartilages of ribs 5-7) Action: Flexes & rotates lumbar vertebrae; Stabilizes pelvis |
External oblique | Origin: Ribs (lower 8) Insertion: Ilium (iliac crest); Linea alba Action: Flexes vertebrae & compresses abdomen; Lateral trunk flexion & rotation |
Internal oblique | Origin: Ilium (iliac crest) Insertion: Pubic bone & lower ribs; Linea alba Action: Flexes vertebrae & compresses abdomen; Lateral trunk flexion & rotation |
Tansversus abdominis | Origin: Ilium (iliac crest); Ribs (lower 6) Insertion: Pubic bone; Linea alba Action: Compresses abdomen |
External intercostals | Origin: Inferior border of rib above Insertion: Superior border of rib below Action: Pulls ribs towards one another to elevate rib cage; Aid in inspiration (synergist to diaphragm) |
Internal intercostals | Origin: Superior border of rib below Insertion: Inferior border of rib above Action: Draws ribs together to depress rib cage |
Diaphragm | Origin: Inferior border of rib cage & sternum; Margins of thoracic cage Insertion: Central tendon of diaphragm Action: Contract to cause inspiration |
Sartorius | Origin: Ilium (anterior superior iliac spine) Insertion: Tibia (medial surface) Action: Flexes & laterally rotates thigh; Flexes knee |
Tensor fasciae latae | Origin: Ilium (iliac crest) Insertion: Iliotibial tract Action: Flexes & abducts thigh; Rotates thigh medially |
Iliopsoas | Origin: Ilium; Lumbar vertebrae Insertion: Femur (lesser trochanter) Action: Flexes thigh towards the trunk; Rotates thigh laterally |
Gluteus maxiumus | Origin: Posterior ilium; Sacrum & coccyx Insertion: Femur (gluteal tuberosity); Iliotibial tract Action: Extends thigh at the hip; Rotates thigh laterally |
Gluteus medius | Origin: Ilium (lateral surface) Insertion: Femur (greater trochanter) Action: Abducts & medially rotates thigh |
Gluteus minimus | Origin: Ilium (lateral surface) Insertion: Femur (greater trochanter) Action: Abducts & medially rotates thigh |
Adductor longus | Origin: Pubic bone (pubic symphysis) Insertion: Femur (linea aspera) Action: Adducts, flexes & medially rotates thigh |
Adductor brevis (humans) Adductor femoris (cats) | Origin: Pubic bone (inferior ramus) Insertion: Femur (linea aspera) Action: Adducts, flexes & medially rotates thigh |
Adductor magnus | Origin: Ischium & pubic bone Insertion: Femur (adductor tubercle & linea aspera) Action: Adducts, flexes & medially rotates thigh (anterior part); Extends thigh (posterior part) |
Pectineus | Origin: Pubic bone (pubic spine) Insertion: Posterior femur Action: Adducts, flexes & medially rotates thigh |
Gracilis | Origin: Pubic bone (pubic symphysis) Insertion: Tibia (proximal medial surface) Action: Adducts thigh; Flexes & medially rotates leg |
QUADRICEPS Rectus femoris | Origin: Ilium (iliac spine) Insertion: Patella & tibia via the patellar ligament Action: Extends leg at knee & flexes thigh at hip |
QUADRICEPS Vastus lateralis | Origin: Femur (greater trochanter) Insertion: Patella & tibia via the patellar ligament Action: Extends leg at knee |
QUADRICEPS Vastus medialis | Origin: Femur (medial surface) Insertion: Patella & tibia via the patellar ligament Action: Extends leg at knee; Stabilizes patella |
QUADRICEPS Vastus intermedius | Origin: Femur (anterior & lateral surface) Insertion: Patella & tibia via the patellar ligament Action: Extends leg at knee |
HAMSTRINGS Biceps femoris (2 heads) | Origin: Long head - Ischium (ischial tuberosity); Short head - Femur (linea aspera) Insertion: Tibia (lateral condyle); Fibula (head) Action: Flexes & rotates leg laterally; Extends thigh |
HAMSTRINGS Semitendinosus | Origin: Ischium (ischial tuberosity) Insertion: Tibia (upper medial surface of shaft) Action: Flexes & rotates leg medially; Extends thigh |
HAMSTRINGS Semimembranosus | Origin: Ischium (ischial tuberosity) Insertion: Tibia (medial condyle) Action: Flexes & rotates leg medially; Extends thigh |
Tibialis anterior | Origin: Tibia (lateral condyle & surface) Insertion: Medial cuneiform & 1st metatarsal Action: Dorsiflexes & inverts foot at angle |
Extensor digitorum longus | Origin: Tibia (lateral condyle) Insertion: Middle & distal phalanges Action: Dorsiflexes foot at ankle; Extends toes |
Fibularis (Peroneus) longus | Origin: Fibula (head) Insertion: By tendon curving under the foot to 1st metatarsal & medial cuneiform Action: Plantar flexes & everts foot at ankle |
Gastrocnemius (2 heads) | Origin: Femur (lateral & medial condyles) Insertion: Calcaneus via calcaneal (Achilles) tendon Action: Plantar flexes at ankle; Flexes leg at knee |
Soleus | Origin: Tibia (posterior surface); Fibula (posterior surface) Insertion: Calcaneus via calcaneal (Achilles) tendon Action: Plantar fleses foot at ankle |
Flexor digitorum longus (tendon posterior to medial malleolus) | Origin: Tibia (posterior surface) Insertion: Distal phalanges of toes 2-5 Action: Plantar flexes & inverts foot at ankle; Flexes toes |
Tibialis posterior | Origin: Tibia (posterior surface); Fibula (posterior surface) Insertion: Under foot medially into tarsals & metatarsals Action: Plantar flexes & inverts foot at ankle |