Muscles Flashcards
Sternocleidomastoid origin
Sternum and clavicle
Sternocleidomastoid insertion
Skull behind ear (Mastoid process)
Sternocleidomastoid use
Elevates sternum and clavicle and ribs
Scalenus Anterior origin
3rd through 6th cervical vertebrae
Scalenus Anterior insertion
Inner border of top of first rib
Scalenus Anterior use
Elevates 1st rib
Scalenus Medius origin
2nd through 7th cervical vertebrae
Scalenus Medius insertion
1st rib
Scalenus Medius use
Elevates first rib
Scalenus Posterior origin
5th through 7th cervical vertebrae
Scalenus Posterior insertion
Outer surface of 2nd rib
Scalenus Posterior use
Elevates 2nd rib
Pectoralis Major origin
Front surface of upper costal cartilages, sternum, and inner half of clavicle
Pectoralis Major insertion
Humerus
Pectoralis Major use
Elevates the sternum and ribs
Pectoralis Minor origin
2nd through 5th ribs near their cartilages
Pectoralis Minor insertion
Front surface of the scapula
Pectoralis Minor use
Elevates 2nd through 5th ribs
Subclavius origin
Undersurface of the clavicle
Subclavius insertion
1st rib near its cartilage
Subclavius use
Elevates 1st rib
Serratus Anterior origin
Outer surfaces of upper 8 or 9 ribs
Serratus Anterior insertion
Front of the scapula
Serratus Anterior use
Elevates upper ribs
External Intercostals description
11 connected muscles that fill the outer portions of the rib interspaces. Form a sheet of muscle
External Intercostals origin
1st rib, cervical vertebrae, and base of skull
External Intercostals insertion
Links each rib to the adjacent rib
External Intercostals use
Elevate ribs and stiffens interspaces
Internal Intercostals description
11 connected muscles that fill the inner portions of the rib interspaces (except at the back of the rib cage)
Internal Intercostals use
Primarily depress ribs and stiffen their interspaces
BUT
intercartilaginous internal intercostal muscles elevate the ribs
Transversus Thoracis origin
Inner surface of the lower sternum and 4th or 5th costal cartilages
Transversus Thoracis insertion
2nd through 6th ribs
Transversus Thoracis use
Depresses 2nd through 6th ribs
Latissimus Dorsi origin
Thoracic vertebrae (lower 6), lumbar vertebrae, and sacral vertebrae, and back surfaces of lower 3 to 4 ribs
Latissimus Dorsi insertion
Humerus
Latissimus Dorsi use
Whole muscles depresses rib cage wall; however, fibers that insert into lower ribs can elevate them
Serratus Posterior Superior origin
Cervical (C7) and thoracic (T1 to T3 or T4) vertebrae
Serratus Posterior Superior insertion
Ribs 2 through 5
Serratus Posterior Superior use
Elevates ribs 2 through 5
Serratus Posterior Inferior origin
Lower thoracic and upper lumbar vertebrae
Serratus Posterior Inferior insertion
Lower border of lower 4 ribs
Serratus Posterior Inferior use
Depresses lower 4 ribs
Lateral iliocostali Cervicis origin
Surfaces of 3rd through 6th ribs
Lateral iliocostalis Cervicis insertion
4th through 6th cervical vertebrae
Lateral iliocostalis Cervicis use
Elevates 3rd through 6th ribs
Lateral iliocostalis Lumborum origin
Lumbodorsal fascia, lumbar vertebrae, and back surface of coxal bone
Lateral iliocostalis Lumborum insertion
Lower edges of lower 6 ribs
Lateral iliocostalis Lumborum use
Depresses lower 6 ribs
Lateral iliocostalis thoracis origin
Upper edges of lower 6 ribs
Lateral iliocostais Thoracis insertion
Lower edges of upper 6 ribs
Lateral iliocostalis Thoracis use
Stabilizes the back of the rib cage wall and moves in concert with the cervicis and/or lumborum parts of the muscle group
Levatores Costarum origin
12 small muscles that originate from 7th cervical vertebrae through 11th thoracic vertebrae
Levatores Costarum insertion
Back surface of the rib below the vertebra of origin
Levatores Costarum use
Elevate the ribs
Quadratus Lumborum origin
Top of the coxal bone
Quadratus Lumborum insertion
1st 4 lumbar vertebrae and lowest rib
Quadratus Lumborum use
Depresses the lowest rib
Subcostals origin
Lower portion of the vertebral column on the inner surfaces of the ribs
Subcostals insertion
Inner surfaces of ribs above
Subcostals use
Depress the ribs
Diaphragm origin
Bottom of the sternum and lower 6 ribs and 1st 3 or 4 lumbar vertebrae
Diaphragm insertion
Central tendon
Diaphragm use
Pulls downward on the central tendon to enlarge the thorax vertically and/or elevates the lower 6 ribs to enlarge the thorax circumferentially
Abdominal Wall muscles (backside)
-Latissimus dorsi
-Lateral iliocostalis lumborum
-Quadratus lumborum
Rectus Abdominus origin
Front edge of coxal bone
Rectus Abdominus insertion
Outer surfaces of 5th through 7th costal cartilages and lower sternum (encased in abdominal aponeurosis)
Rectus Abdominus use
Depresses lower ribs and sternum
External Oblique origin
Upper surface of the coxal bone and abdominal aponeurosis near the midline
External Oblique insertion
On the lower 8 ribs
External Oblique use
Depresses lower 8 ribs and forces front and sides of abdominal wall inward
Internal Oblique origin
Upper surface of the coxal bone and lumbodorsal fascia
Internal Oblique insertion
Abdominal aponeurosis lower borders of the costal cartilages of the lower 3 to 4 ribs
Internal Oblique use
Depresses lower ribs and forces front and sides of abdominal wall inward
Transversus abdominis origin
Upper surface of the coxal bone, lumbodorsal fascia, and inner surfaces of the costal cartilages of ribs 7 through 12
Transversus Abdominis insertion
Into abdominal aponeurosis
Transversus Abdominis use
Forces front and sides of abdominal wall inward
