Unit 9: Key Terms

Structure of a skeletal muscle

blood vessels, nerves, connective tissue

Fiber

individual muscle cell

Endomysium

connective tissue layer that surrounds individual muscle cells (fibers)

Fasicle

a bundle of skeletal muscle fivers surrounded by perimysium

Perimysium

a connective tissue sheath that surrounds individual muscle fascicles

Epimysium

outer fibrous connective tissue wrapping surrounding (enclosed) fascicles

Fascia

most superficial connective tissue sheath: continuous with epimysium

Naming muscles

based on specific muscles appearance, size, or position

Naming muscles: Actions performed

flexors, extensors, adductors, abductors, levators

Functional Groups of muscles

take the cooperation of several individual muscles working as a group to perform the movement (action): roles of different muscles in a group

Agonists (prime movers)

provide most force for given muscle action

Antagonists

usually opposite side of bones and joint where they meet, opposite action of agonist

Synergists

aid agonists by supplying supplemental force, minimizing unwanted movement, helping stabilize joints

Fixators

also provide stabilizing force that anchors bone, provides movement efficiency and protection from injury due to unnecessary movements

Muscle origin and insertion

skeletal muscles begin and end at distinct anatomical locations

Origin

anchoring point on bone where skeletal muscle "originates from", typically not involved directly with movement of joint

Insertion

moving end of muscle whose tendon attaches to bone or other structures, usually on far side of joint

Lever System

3 components, load resistance, applied force that moves load, pivot point (fulcrum), changing configuration of these variables leads to lever classes

Superficial muscles: anterior view

head, shoulder, forearm, pelvis/thigh, leg, facial, neck, thorax, abdomen

Superficial muscles: posterior view

arm, forearm, leg, thigh, hip, shoulder, neck

Muscles of facial expression

occipitalis, epicranial aponeurosis, frontalis, orbicularis oculi, obicularis oris, platysma, zygomaticus minor and major, buccinator

Muscles of head

temporalis, maseter

Muscles of the neck

sternocleidomastoid, splenius capitis

Entrinsic Eye and Orbit muscles

each eye has six muscles attached to outer surface, allowing for quick and accurate movements, directing our vision

Four rectus muscles

superior, inferior, medial, lateral, named from straight line they take from origin to more anterior insertion

Superior and inferior oblique muscles

attach to eye at angle

Muscles of the vertebral column

critical for both locomotion and posture

Erector spinae

group of muscles along vertebral column and posterior ribs, mostly powerful extensors of the spine, also lateral bending and rotation

Erector spinae: spinalis

most medially situated muscle group on either side of vertebral column

Erector spinae: longissimus

just lateral to spinalis group

Erector Spinae: Iliocostalis

most lateral group

Quadratus lumborum

large, deep muscle, allowing the vertebral column to extend and bend laterally

Muscles of trunk

muscles grouped together by anatomical proximity, function, or both

Muscles of respiration

diaphragm, internal intercostals, and external intercostals

Abdominal muscles

rectus sheath, rectus abdominis, linea alba, internal oblique, transversus abdominis, external oblique

Transverse abdominis

located under the obliques it is the deepest of the abdominal muscles and wraps around your spine for protection and stability

Internal abdominal oblique

located under the external obliques, running in opposite direction

External abdominal oblique

located on the side and front of the abdomen

Rectus abdominis

located along the front of the abdomen, most well know abdominal muscle, "six pack"

Muscles of shoulder and arm: anterior view, Deltoid

shoulder muscle

Muscles of shoulder and arm: anterior view, Pectoralis major

large, superficial

Muscles of shoulder and arm: anterior view: Pectoralis minor

smaller, more deep

Muscles of shoulder and arm: anterior view: Serratus anterior

lateral side of ribs, "serrated"

Muscles of shoulder and arm: anterior view: Coracobranchialis

goes from the coracoid process, to the arm region down

Muscles of shoulder and arm: Posterior view: Trapezius

looks like a trapezoid, neck and back muscle

Muscles of shoulder and arm: Posterior view: Latissimus dorsi

superficial back muscle

Muscles of shoulder and arm: Posterior view: Levator scapulae

elevate our scapulae, deep muscle

Muscles of shoulder and arm: Posterior view: Rhomboid minor

small, deep muscle, looks like a rhombus

Muscles of shoulder and arm: Posterior view: Rhomboid Major

large, deep muscle, looks like a rhombus

Arm muscles: Biceps brachii

2 heads, superficial to brachialis

Arm muscles: Brachialis

2 heads, deep to biceps brachii

Arm muscles: Triceps brachii

underside of arm, three heads

Arm muscles: Brachioradialis

runs from the brachii to the radius

Rotator cuff

supraspinatus, infraspinatus, teres minor and major

Wrist flexors of the anterior forearm

flexor carpi radialis, palmaris longus, flexor carpi ulnaris

Finger and thumb flexors (deep anterior forearm)

flexor digitorum superficialis

Forearm Pronators

pronator teres, pronator quadratus

Forearm supinater

supinator

Wrist extensors of posterior and lateral forearm

extensor carpi radialis longus, extensor carpi radialis brevis, extensor carpi ulnaris

Extensors of fingers and thumb

extensor digitorum

Muscles of thigh and leg: Psoas major

lumbar vertebrae-> femur, part of lliopsoas

Muscles of thigh and leg: lliacus

iliac crest -> femur, broad, part of the iliopsoas

Muscles of thigh and leg: Gluteus Maximus

superficial muscle

Muscles of thigh and leg: Gluteus medius

upper posterior butt muscle, lies under gluteus maximus

Muscles of thigh and leg: Gluteus minimus

deep muscle, smaller

Muscles of thigh and leg: Piriformis

behind the gluteus maximus, runs diagonally from the lower spine to the upper surface of the femur

Muscles of thigh and leg: Tensor fasciae latae

IT band, proximal anterolateral thigh

Muscles of thigh and leg: Pectineus

pubic bone to the femur

Muscles of the thigh and leg: Adductors: Adductor Brevis

short, lateral

Muscles of the thigh and leg: Adductors: Adductor Longus

longer, lies in the middle

Muscles of the thigh and leg: Adductors: Adductor Magnus

largest one, interior of thigh

Muscles of the thigh and leg: Gracilis

interior of thigh, most medial

Muscles of the thigh and leg: Sartorius

runs obliquely over the adductors and gracilis

Muscles of the thigh and leg: Hamstrings: Biceps Femoris

lateral, long and short head

Muscles of the thigh and leg: Hamstrings: Semitendinosus

superficicial to semimenbranosus

Muscles of the thigh and leg: Hamstrings: Semimembranosus

deep to semitendinosus

Quads Group: Rectus Femoris

most superficial

Quads Group: Vastus medialis

medial

Quads Group: Vastus lateralis

lateral

Quads Group: Vastus intermedius

deep to rectus femoris

Lower leg muscles: Tibialis Anterior

medial

Lower leg muscles: Extensor Hallucis longus

long, connects to the big toe

Lower leg muscles: Extensor digitorum longus

connects to digits, lateral

Calf muscle

gastrocnemius

Calf muscles: Soleus

deep to gastrocnemius muscle

Calf muscle: Achilles tendon

connects your calf muscle in the back of your low leg to the heel bone in your foot

Calf muscles: Plantaris

runs down back of leg