Kine 2031 Muscles study guide
Hinge joint
uniaxial movement, flexion and extension
Muscles that abduct the humerus
Deltoid (spinal, acromial, clavicular)
Supraspinatus
Sternocleidomastoid
Origin: Clavicle, Sternum
Insertion: Mastoid Process of temporal bone
Actions: Lateral flexion of head and neck, Rotation of head
Erector Spinae
Origin: Iliac crest, Sacrum, lumbar and thoracic spinous process
Insertion: Ribs, Transverse/spinous processes of cervical/thoracic
vertebrae
Actions: Back extension, lateral flexion of back
Quadratus Lumborum
,Origin: Iliac crest
Insertion: Inferior border of rib 12, L1-L4
Actions: Lateral flexion of back
Neck Muscles
Sternocleidomastoid
External Intercostals
Origin: Rib above
Insertion: Rib below
Action: Inspiration
Internal Intercostals
Origin: Rib below
Insertion: Rib above
Action: Expiration
Innermost Intercostals
,Origin: Rib below
Insertion: Rib above
Action: Expiration
Diaphragm
Origin: Lumbar vertebrae, inferior ribs, xiphoid process
Insertion: Central tendon
Action: Increases vertical dimensions for thorax (inspiration)
Abdominal muscles
Perform trunk flexion
Consists of: External oblique, Rectus abdominis, Internal Oblique
Deepest: Transverse abdominis
Rectus Abdominis
Origin: Pubis bone
Insertion: Xiphoid process, lower ribs
Action: Trunk flexion, increases intra-abdominal pressure
External Oblique
, Origin: Outer surface of ribs
Insertion: Linea alba, inguinal ligament
Action: Trunk flexion/rotation/lateral flexion, increases intra-abdominal
pressure (twist)
Internal Oblique
Origin: Lumbar fascia, iliac crest
Insertion: Lubea alba, lower ribs
Action: Trunk flexion/rotation/lateral flexion, increases intra-abdominal
pressure (twist)
Transversus Abdominis
Origin: Lumbar fascia, iliac crest, inguinal ligament (deep to external
and internal obliques)
Insertion: Linea alba
Action: Increases intra-abdominal pressure
Trapezius
Origin: Nuchal ligament, spines of thoracic vertebra, Occipital bone
Insertion: Clavicle, Acromion process, spine of scapula
Hinge joint
uniaxial movement, flexion and extension
Muscles that abduct the humerus
Deltoid (spinal, acromial, clavicular)
Supraspinatus
Sternocleidomastoid
Origin: Clavicle, Sternum
Insertion: Mastoid Process of temporal bone
Actions: Lateral flexion of head and neck, Rotation of head
Erector Spinae
Origin: Iliac crest, Sacrum, lumbar and thoracic spinous process
Insertion: Ribs, Transverse/spinous processes of cervical/thoracic
vertebrae
Actions: Back extension, lateral flexion of back
Quadratus Lumborum
,Origin: Iliac crest
Insertion: Inferior border of rib 12, L1-L4
Actions: Lateral flexion of back
Neck Muscles
Sternocleidomastoid
External Intercostals
Origin: Rib above
Insertion: Rib below
Action: Inspiration
Internal Intercostals
Origin: Rib below
Insertion: Rib above
Action: Expiration
Innermost Intercostals
,Origin: Rib below
Insertion: Rib above
Action: Expiration
Diaphragm
Origin: Lumbar vertebrae, inferior ribs, xiphoid process
Insertion: Central tendon
Action: Increases vertical dimensions for thorax (inspiration)
Abdominal muscles
Perform trunk flexion
Consists of: External oblique, Rectus abdominis, Internal Oblique
Deepest: Transverse abdominis
Rectus Abdominis
Origin: Pubis bone
Insertion: Xiphoid process, lower ribs
Action: Trunk flexion, increases intra-abdominal pressure
External Oblique
, Origin: Outer surface of ribs
Insertion: Linea alba, inguinal ligament
Action: Trunk flexion/rotation/lateral flexion, increases intra-abdominal
pressure (twist)
Internal Oblique
Origin: Lumbar fascia, iliac crest
Insertion: Lubea alba, lower ribs
Action: Trunk flexion/rotation/lateral flexion, increases intra-abdominal
pressure (twist)
Transversus Abdominis
Origin: Lumbar fascia, iliac crest, inguinal ligament (deep to external
and internal obliques)
Insertion: Linea alba
Action: Increases intra-abdominal pressure
Trapezius
Origin: Nuchal ligament, spines of thoracic vertebra, Occipital bone
Insertion: Clavicle, Acromion process, spine of scapula
