8 8 Major Skeletal Muscles What muscle names
- Slides: 40
8. 8 Major Skeletal Muscles
What muscle names tell us Relative size v Shape v Location v Action v Number of attachments v Direction of fibers v
Examples Zygomaticus – originates at the zygomatic bone v Gluteus maximus – originates in the gluteal region and is a large muscle v Tibialis anterior – originates on the anterior surface of the tibia v
Muscles of Facial Expression
Epicranus Origin – occipital bone v Insertion – skin and muscles around eye v Action – raises eyebrow v
Orbicularis oculi Origin – maxillary and frontal bones v Insertion – skin around eye v Action – closes eye v
Orbicularis oris Origin – muscles near the mouth v Insertion – skin of lips v Action – closes and protrudes lips v
Buccinator Origin – outer surfaces of maxilla and mandible v Insertion – orbicularis oris v Action – compresses cheeks inward v
Zygomaticus Origin – zygomatic bone v Insertion – orbicularis oris v Action – raises corner of mouth v
Platysma Origin – fascia in upper chest v Insertion – lower border of mandible v Action – draws angle of mouth downward v
Muscles of Mastication
Masseter Origin – lower border of zygomatic arch v Insertion – lateral surface of mandible v Action – closes jaw v
Temporalis Origin – temporal bone v Insertion – coronoid process and lateral surface of mandible v Action – closes jaw v
Muscles that move the head
Sternocleidomastoid Origin – anterior surface of sternum and upper surface of clavicle v Insertion – mastoid process of temporal bone v Action – pulls head to one side, pulls head toward chest, or raises sternum v
Splenius capitis Origin – spinous processes of lower cervical and upper thoracic vertebrae v Insertion – mastoid process of temporal bone v Action – rotates head, bends head to one side, or brings head into an upright position. v
Semispinalis capitis Origin – processes of lower cervical and upper thoracic vertebrae v Insertion – occipital bone v Action – extends head, bends head to one side, or rotates head. v
Muscles that move the pectoral girdle Closely associated with those that move the arm. v Many of these move the scapula up and down, back and forth. v
Muscles that move the pectoral girdle
Trapezius Origin – occipital bone and spines of cervical and thoracic vertebrae v Insertion – clavicle; spine and acromion process of scapula v Action – rotate scapula and raises arm, raises scapula, pulls scapula medially or pulls scapula and shoulder downward. v
Rhomboideus major Origin – spines of upper thoracic vertebrae v Insertion – medial border of scapula v Action – raises and adducts scapula v
Levator scapula Origin – transverse process of cervical vertebrae v Insertion – medial margin of scapula v Action – elevates scapula v
Serratus anterior Origin – outer surface of upper ribs v Insertion – ventral surface of scapula v Action – pulls scapula anteriorly and downward v
Pectoralis minor Origin – sternal ends of upper ribs v Insertion – coracoid process of scapula v Action – pulls scapula anteriorly and downward or raises ribs v
Muscles that move the arm Arm is freely movable. v Muscles are grouped by their primary action. v Flexion – flexors v Extension – extensors v Abduction – abductors v Rotation - rotators v
Flexors Coracobrachialis v Pectoralis major v
Coracobrachialis
Extensors Teres major v Latissimus dorsi v
Abductors Supraspinatus v Deltoid v
Rotators Subscapularis v Infraspinatus v Teres minor v
Muscles that move the forearm Most forearm movement is accomplished by muscles that connect the radius or ulna to the humerus or pectoral girdle. v Again, we have flexors, extensors and rotators. v
Flexors Biceps brachii v Brachialis v Brachioradialis v
Extensor v Triceps brachii
Rotators Supinator v Pronator teres v Pronator quadratus v
Muscles that move the hand v v v Flexors Anterior side Flexor carpi radialis Flexor carpi ulnaris Palmaris longus Flexor digitorum profundus v v v Extensors Posterior side Extensor carpi radialis longus Extensor carpi radialis brevis Extensor carpi ulnaris Extensor digitorum
Muscles of the abdominal wall External oblique v Internal oblique v Transversus abdominis v Rectus abdominis v
Muscles of the pelvic outlet v v Pelvic diaphragm Levator ani v v Urogenital diaphragm Superficial transversus perinei Bulbospongiosus Ischiocavernosus
Muscles that move thigh Anterior group v v Psoas major Iliacus Posterior group v v Gluteus maximus Gluteus medius Gluteus minimus Tensor fasciae latae
Muscles that move the leg Flex the knee v v Biceps femoris Semitendinosus Semimembranosus Sartorius Extend the knee v v v Quadriceps femoris group, consisting of: Rectus femoris Vastus lateralis Vastus medialis Vastus intermedius
Muscles that move the foot Dorsal flexors v v v Tibialis anterior Fibularis Extensor digitorum Plantar flexors v v v Gastrocnemius Soleus Flexor digitorum longus
- Major muscle
- Skeletal and muscular system
- Fusiform muscle
- Gap junction in smooth muscle
- Skeletal muscles
- Muscles of the leg
- Naming skeletal muscles
- Microscopic anatomy of skeletal muscles
- Secretory tissue
- How are muscles named
- Skeletal muscles anterior view
- Naming muscles
- Organization of muscle
- T tubules
- Cross bridge anatomy
- Skeletal muscle belly
- Microscopic anatomy of skeletal muscle figure 6-2
- Purpose of smooth muscle
- Cardiac skeletal and smooth muscle comparison
- Skeletal muscle tissue structure
- Centrally acting skeletal muscle relaxants
- Specialized connective tissue blood
- Structure of skeletal muscle
- Label the superficial muscles
- Skeletal muscle
- Skeletal muscle
- Multinucleated muscle cells
- Filament bending
- Skeletal muscle crash course
- 2 functions of muscles
- Is skeletal muscle an organ
- Lesson 5.1 the organization of a skeletal muscle
- Slide
- Macro and micro structure of the skeletal muscle
- Pseudostratified vs simple columnar
- Dantrolene
- Cardiac muscle cell vs skeletal
- Microscopic anatomy of skeletal muscle
- Skeletal muscle tissue
- Comparison of skeletal cardiac and smooth muscle
- Contractile unit of muscle