Muscles Masterlist Flashcards
OINAs
Latissimus Dorsi
A: extend, adduct, IR shoulder
PA: thoracolumbar fascia, iliac crest, ribs 9/10-12, SP T7-T12, *inferior angle
DA: intertubercular sulcus of humerus
N: thoracodorsal nerve (C6, C7, C8)
Trapezius
UT A: bilateral extension of head and neck; unilateral ipsilateral lateral flexion & contralateral rotation of head and neck; elevate & upwardly rotate scapula
MT A: adduct/retract & stabilize scapula
LT A: depress & upwardly rotate scapula
PA: external occipital protuberance, superior nuchal line, nuchal ligament, SP C7-T12
DA: lateral 1/3 clavicle, acromion, spine of scapula
N: spinal accessory nerve (CN XI), ventral rami C3 and C4
Levator Scapulae
A: elevate & downwardly rotate scapula
PA: TP C1-C4
DA: medial border of scapula (b/w superior angle and root)
N: dorsal scapular nerve (C4, C5), cervical C3 and C4
Rhomboid Major/Minor
A: adduct/retract & downwardly rotate scapula, fix scapula to thoracic wall
PA: (major) SP T2-T5, (minor) nuchal ligament & SP C7-T1
DA: (major) medial border of scapula b/w root and inferior angle, (minor) medial border of scapular spine
N: dorsal scapular nerve (C4, C5)
Splenius
A: bilateral extension of head and neck, unilateral ipsilateral lateral flexion & ipsilateral rotate of head and neck
PA: nuchal ligament, SP C7-T6
DA: (capitis) mastoid process & superior nuchal line, (cervicis) TP C1-C4
N: dorsal rami of spinal nerves
Erector Spinae Group
A: bilateral extension of vertebral column, unilateral lateral flexion of vertebral column
PA: thoracolumbar fascia, iliac crest, SP T11-L5
DA: (iliocostalis) lower rib angles & cervical TP, (longissimus) b/w rib tubercles and angles to thoracic TP, (spinalis) upper thoracic SP & cranium
N: dorsal rami of spinal nerves
Rotatores
A: bilateral local extension of vertebral column, unilateral contralateral rotation of vertebral column
IA: TP of vertebrae
SA: SP C2-L5 (spans 1-2 segments)
N: dorsal rami of spinal nerves
Multifidus
A: bilateral extension of vertebral column, unilateral contralateral rotation of vertebral column, stabilize vertebrae
IA: SI ligaments, TP T1-T3, aponeurosis of erector spinae group, axillary processes C4-C7, mammillary processes L1-L5, PSIS, posterior sacrum
SA: SP of vertebrae (spans 2-4 segments)
N: dorsal rami of spinal nerves
Semispinalis
A: bilateral extension and unilateral contralateral rotation of head, neck, and thoracic spine
IA: TP C4-T12
SA: cervical and upper thoracic SP, occipital bone (spans 4-6 segments)
N: dorsal rami of spinal nerves
Rectus Capitis Posterior Major
A: rock and tilt head into extension, unilateral ipsilateral rotation of head
O: SP C2
I: lateral inferior nuchal line
N: suboccipital nerve (dorsal ramus C1)
Rectus Capitis Posterior Minor
A: rock and tilt head into extension, unilateral ipsilateral rotation of head
O: posterior tubercle of C1
I: medial inferior nuchal line
N: suboccipital nerve (C1)
Obliquus Capitis Superior
A: rock and tilt head into extension, ipsilateral lateral flexion of head
O: TP C1
I: occipital bone b/w nuchal lines
N: suboccipital nerve (C1)
Obliquus Capitis Inferior
A: ipsilateral rotation of head
O: SP C2
I: TP C1
N: suboccipital nerve (C1)
Deltoid
A: (anterior/clavicular) flex & IR shoulder, (middle/acromial) abduct shoulder, (posterior/spinal) extend & ER shoulder
O: clavicle, acromion, spine of scapula
I: deltoid tuberosity of humerus
N: axillary nerve (C5, C6)
Pectoralis Major
A: adduct, IR, and horizontally adduct shoulder; draw scapula anteriorly and inferiorly; (clavicular head) flex shoulder; (sternocostal head) extend shoulder from flexed position
O: (clavicular head) clavicle; (sternocostal head) sternum, superior six costal cartilages, external oblique muscle
I: lateral lip of intertubercular sulcus of humerus
N: medial and lateral pectoral nerves; clavicular head (C5, C6), sternocostal head (C7, C8, T1)
Pectoralis Minor
A: stabilize scapula against thoracic wall; (w/ fixed scapula) elevate thorax during forced inhalation
O: ribs 3-5
I: coracoid process
N: medial (C8, T1) and lateral (variable) pectoral nerves
Teres Major
A: extend, adduct, IR shoulder
O: posterior surface of inferior angle of scapula
I: medial lip of intertubercular sulcus of humerus
N: lower subscapular nerve (C5, C6)
Supraspinatus
A: initiates and assists w/ shoulder abduction, stabilize head of humerus in glenoid cavity
O: supraspinous fossa of scapula
I: greater tubercle of humerus
N: suprascapular nerve (C4, C5, C6)
Infraspinatus
A: ER shoulder, stabilize head of humerus in glenoid cavity
O: infraspinous fossa of scapula
I: greater tubercle of humerus
N: suprascapular nerve (C5, C6)
Teres Minor
A: ER shoulder (helper), stabilize head of humerus in glenoid cavity
O: lateral border of scapula
I: greater tubercle of humerus
N: axillary nerve (C5, C6)
Subscapularis
A: IR shoulder, stabilize head of humerus in glenoid cavity
O: subscapular fossa of scapula
I: lesser tubercle of humerus
N: lower and upper subscapular nerve (C5, C6, C7)
Serratus Anterior
A: draw scapula anteriorly and inferiorly, upwardly rotate scapula, hold scapula against thoracic wall
O: lateral parts of ribs 1-8/9
I: medial border of scapula
N: long thoracic nerve (C5, C6, C7)
Sternocleidomastoid
A: unilateral lateral flexion & contralateral rotation of head and neck; bilateral extension (OA joint), flexion (cervical vertebrae), and/or extension of superior cervical w/ flexion of inferior cervical
SA: mastoid process, superior nuchal line
DA: (sternal head) manubrium of sternum, (clavicular head) medial 1/3 clavicle
N: spinal accessory nerve (CN XI), C3 and C4
Platysma
N: facial nerve (CN VII)
Suprahyoids
mylohyoid, geniohyoid, stylohyoid, digastric (anterior and posterior belly)
Infrahyoids
thyrohoid, sternohyoid, sternothyroid, omohyoid (superior and inferior belly)
Intercostals
A: (external) elevate ribs during inhalation, (internal) depress ribs during exhalation
O: inferior border of rib above
I: superior border of rib below
N: thoracic - segmental intercostal nerve
Diaphragm
A: draw central tendon down to increase volume of thoracic cavity during inhalation
O: (sternal) inner part of xiphoid process, (costal) inner surface of ribs 7-12, (lumbar) L1-L2/3
I: central tendon
N: phrenic nerve (C3, C4, C5)
Serratus Posterior Superior/Inferior
forced breathing
superior: SP C7-T3, elevate ribs w/ inhalation
inferior: SP T12-L3, depress ribs w/ exhalation
Quadratus Lumborum
A: unilateral lateral tilt/hike of pelvis, unilateral extension and lateral flexion of vertebral column, bilaterally fix rib 12 during forced inspiration
SA: rib 12, tips of TP L1-L5
IA: iliac crest, iliolumbar ligament
N: ventral branches T12, L1-L4
Psoas Major
A: balance trunk; acts superiorly to laterally flex vertebral column; acts inferiorly w/ iliacus to flex hip and (while sitting) flex trunk
SA: TP T12-L5, sides of lumbar vertebral bodies, discs b/w them
IA: lesser trochanter of femur
N: ventral rami L1, L2, L3
Iliacus
A: (w/ psoas major) hip/thigh flexion, stabilize hip joint
SA: iliac fossa, anterior sacroiliac ligaments, sacrum
IA: lesser trochanter of femur, psoas tendon
N: femoral nerve (L2, L3, L4)
Rectus Abdominis
fibers run vertically
A: flexion of vertebral column, compress abdominal viscera, posterior tilt of pelvis
N: thoraco-abdominal nerves (ventral rami T6-T12)
External Oblique
fibers run down and in
A: bilateral flexion of vertebral column, unilateral lateral flexion and contralateral rotation of vertebral column, compress abdominal contents
N: thoraco-abdominal nerves (ventral rami T7-T11), subcostal nerve
Internal Oblique
fibers run down and out
A: bilateral flexion of vertebral column, unilateral lateral flexion and ipsilateral rotation of vertebral column, compress abdominal contents
N: thoraco-abdominal nerves (ventral rami T6-T12), first lumbar nerve
Transversus Abdominis
fibers run horizontally
A: compress and support abdominal viscera, antagonist of diaphragm w/ expiration
N: thoraco-abdominal nerves (ventral rami T6-T12), first lumbar nerve
Pelvic Floor Superficial Layer
- ischiocavernosus
- bulbospongiosus
- superficial transverse perineal muscle
- external anal sphincter
- innervated by pudendal nerve (S2, S3, S4)
Pelvic Floor Deep Layer
- levator ani (puborectalis, pubococcygeus, iliococcygeus)
- coccygeus
- obturator internus = side wall
- piriformis = back wall
