Axial Anatomy muscles Flashcards
External oblique
Outer surface ribs 5-12 and costal cartilages
- linea alba via anterior rectus sheath
Inguinal ligament
Anterior 2/3 iliac crest
Anterior rami t7-12
External oblique actions
Bilateral- trunk flexion
Posterior pelvic tilt
Unilaterally- contralateral rotation
Ipsilateral- lateral side flexion
Internal oblique
-Lower border ribs 10-12 Linea alba via ant + post rectus sheath Pectin pubis - Lateral 2/3 inguinal ligament Anterior 2/3 iliac crest Thoracolumbar fascia
Anterior rami t7-12
Internal oblique actions
Bilaterally- trunk flexion against resistance
Posterior pelvic tilt
Ipsilateral- rotation
Lateral side flexion
Transverse abdominus
- Internal surfaces ribs 7-12 costal cartilages Thoracolumbar fascia Iliac crest Lateral 1/3 inguinal ligament - Linea alba via rectus sheath Pectin pubis
Anterior rami T7-12
Transverse abdominus actions
Stabilises lumbar spine
Raise intra abdominal pressure
Rectus abdominus
-Xiphoid process
Costal cartilages of rib 5-7
- Pubic symphysis
Pubic crest
Anterior rami T6-12
Rectus abdominus actions
Bilateral- trunk flexion
Posterior pelvic tilt
Contralaterally- rotation
Ipsilaterally- lateral side flexion
Functions of abdominals
Trunk movement
Protection of abdominal viscera
Spinal stabilisation
Abdominal pressure- forced expiration, micturition, defecation, parturition, vomiting
Sitting up from lying, getting out of bed
Quadratus lumborum
- Medial half lower border rib 12
TP lumber vertebrae L5
Iliolumbar ligament
-Iliac crest
Ventral roots T12-L4
Quadratus lumborum actions
Ipsilaterally- lateral side flexion
Bilaterally- lumbar extension
Depress and stabilise rib 12
Muscle of deep inspiration
Erector spinae
Medial limb- Spinalis
-Lower 6 ribs and rib angles
- T11-L5 SP
Supraspinous ligament
Sacro-iliac ligament
Medial sacral crest
Dorsal rami of adjacent throacolumbar nerves
Erector spinae
Lateral limb- Iliocostalis
Lower six ribs and rib angles - Lateral sacral crest Sacrotuberous ligament Sacrococcygeal ligament Posterior sacro iliac ligament Posterior iliac crest
Dorsal rami of adjacent throacolumbar nerves
Erector spinae
Deep limb- Longissimus
Lower 6 ribs and rib angles
- iliac tuberosity
Inner lip of iliac crest
Dorsal rami of adjacent throacolumbar nerves
Erector spinae actions
Bilaterally- extension of vertebral column
Control of flexion
Unilaterally- Ipsilateral lateral side flexion
Ipsilateral rotation
Maintains lumbar lordosis
Semispinalis
TP T6-10
Lower cervical and upper thoracic SP
Semispinalis action
Bilaterally- Extension of cervical and thoracic spine
Unilaterally- Assists rotation
Rotatores action
Stabiliser
Contralateral- rotation
Interspinales action
Stabiliser muscle
Intertransversus action
Stabiliser
Ilsilaterally- Lateral side flexion
Multifidus actions
Bilaterally- Extension
Unilaterally- Ipsilateral Lateral side flexion
Contralateral rotation
Sternocleidomastoid
Sternal head- Upper anterior manubrium
Lateral 1/2 superior nuchal line of occipital bone
Clavicular head- Superior surface medial 1/3 clavicle
Lateral surface mastoid process of temporal bone
Sternocleidomastoid actions
Ipsilateral- shoulder tilt/ lateral side flexion Contralateral- head rotation Bilateral- cervical spine flexion Draws head anteriorly Accessory muscle of respiration
Diaphragm
Peripheral attachments:
Anteriorly- costal surface xiphoid process
Costal margin/thoracic wall
Laterally- Ends of ribs 11-12
Posteriorly- Lumbar vertebrae
Medial and lateral arcuate ligaments
Left crura- L1-2 and intervertebral disc
Right crura- L1-3 and intervertebral disc
Central attachment:
Muscle fibres converge forming central tendon
Diaphragm actions
Contracts and flatterns during inspiration
Increases thoracic pressure so air enters
Diaphragm function
Helps with: Breathing and inspiration Core stability Active contraction in labour or urination Vomiting
Scalenes
Anterior- TP C3-6
- Rib 1
Medius- Tp C1-7
- Rib 1
Posterior- TP C4-6
- Rib 2
Ant- ventral rami c4-6
Med- ventral rami c3-8
Post- ventral c6-8
Scalenes actions
Unilaterally- Ipsilateral lateral side flexion
Bilaterally- cervical flexion
Accessory muscle of respiration- Elevates rib 1
External Intercostal
Inferior margin of superior rib (Ribs 1-11)
Superior margin of inferior rib (Ribs 2-12)
External intercostal actions
Rib elevation
Increasing transverse dimensions of thoracic cavity
Most active in inspiration
Internal intercostals
Lateral edge of costal groove of superior rib
Superior margin of inferior rib
Internal intercostal actions
Depress ribs
Decreases transverse dimensions of thoracic
Support intercostal space
Most active in expiration
Innermost intercostals
Inferior margin and internal surface of costal cartilage ribs 2-6
Inferior aspect of deep xiphoid process
Costal cartilage ribs 4-7
Innermost intercostals
Decreases transverse dimensions of thoracic cavity.
Active in expiration
Serratus anterior
Outer surfaces upper 8-9 ribs
Deep fascia overlaying deep intercostal space
Costal surface medial border of scapula
Serratus anterior actions
Protraction of scapula
Lateral rotation of scapula
Long thoracic c5-7
Pectoralis major
Inferior and anterior clavicular
Anterior sternum
First 7 costal cartilages
Aponeurosis of external obliques
Lateral lip of intertubercular groove
Pectoralis major action
Clav- flexion (sternal RI)
Sternal- extension (clav RI)
Both- adduction and MR humerus
Medial and lateral pectoral nerves c5-8
Latissimus dorsi
Thoracolumbar fascia from SP T6-12 and all of sacral and lumbar vertebrae Iliac crest Inferior angle of scapula Lower 4 ribs Some fibres to sacrum and coccyx
Floor of intertubercular groove
Latissimus dorsi action
Extension, MR and adduction of humerus
Respiratory action when arms fixed (deep cough)
Thoracodorsal nerve C6-8
Muscles of inspiration
Diaphragm
External intercostals
Serratus posterior superior
Muscles of respiratory distress
Sternocleidomastoid (sternomastoid) Scaleni Serratus anterior Pectoralis major Pectoralis minor Latissimus dorsi
Muscles of forced expiration
Intercostal muscles Transversus Thoracis Subcostals Serratus posterior inferior External oblique Internal oblique Rectus abdominus Transversus abdominus Latissimus dorsi Quadratus lumborum
Transverus thoracis actions
Depress costal cartilages
Longus capitis actions
Unilaterally- ipsilateral lateral side flexion
Bilaterally- cervical spine flexion
Supports cervical lordosis
Longus colli actions
Bilaterally- cervical spine flexion
Unilaterally- ipsilateral side flexion
Supports cervical lordosis
Rectus capitis anterior and lateralis action
Deep cervical flexion
Stabiliser muscle
Ipsilateral lateral flexion
Rectus capitis posterior minor and major
Obliqus capitis inferior and superior
Bilaterally- upper cervical extension
Unilaterally- Ipsilateral lateral flexor
Levator scapulae
C1–4 TP
Medial scapula border
Levator scapulae actions
Elevation of scapula
Ipsilateral lateral flexion
Cervical neck extension
Dorsal scapula nerve C5
Levator scapulae function
Scapula stability
Resists depression with weight in hand
Upper trapezius
External occipital protuberance
Medial 1/3 superior nuchal line
Ligamentum nuchae
SP T7-12 and supraspinous ligament
Posterior border lateral 1/3 clavicle
Upper trapezius actions
Cervical spine- bilaterally- cervical spine extension
Unilaterally- ipsilateral lateral side flexion
Shoulder girdle/scapula- elevation of shoulder girdle
Upwards scapula rotation
Thoracic outlet syndrome
Between scapula anterior and middle the whole brachial plexus and arterial supply to upper limbs and venous supply return to upper limb exits.
Splenius cervicis actions
Bilaterally- cervical spine extension
Unilaterally- ipsilateral lateral flexion
Rotation
Splenius capitis actions
Extension of cervical spine and head
Neck and head retraction
Semispinalis capitis actions
Bilaterally- cervical extension
Unilaterally- ipsilateral lateral side flexion
Stability muscle
