Superficial Back Flashcards
External occipital protuberance
Midline bony prominence in the occipital bone.
Same level as superficial nuchal line.
Attachments:
1) Nuchal ligament
2) Trapezius muscle
Mastoid process
Pyramidal bony projection from the posterior section of the temporal bone.
4 attachments (all neck muscles):
1) SCM
2) Splenius capitus
3) Posterior belly of digastric muscle
4) Longissimus capitis
Superior nuchal line
Marks superior limit of neck.
Upper ridge.
Extends on either side of EOP.
Attachments:
1) Trapezius
2) Transversospinalis (splenius, erector spinae, transversospinalis)
Spinous processes of vertebrae
Median posterior projections of spine
- absent C1
- C3-C5 = bifid
- C7 = vertebra prominence
- Long + sloping T-spine
- Hatchet-shaped in L-spine
Iliac crest
Superior edge of ilium
*Landmark for L4
Scapula
Shoulder blade
*Inferior angle = landmark for T7
Spine of scapula
Ridge dividing posterior of scapula into:
1) Supraspinous fossa
2) Infraspinous fossa
Acromion process
Subcutaneous lateral point of scapula (palpable)
*Forms AC joint
Occipital artery
Origin: External carotid artery, emerges cranial border of splenius capitus
Course: Passes to posterior belly of digastric + mastoid processes; follows occipital nerve
Supplies: Scalp on back of head, as far as vertex
Greater occipital nerve
Origin: Medial branch of posterior ramus of spinal nerve C2
Course: Emerges btwn axis + obliquus capitis inferior; then pierces trapezius
Innervates: scalp region of occipital
Posterior cutaneous nerves + vessels
Superior neurovasculature supplying skin/cutaneous aspects posteriorly
*changes planes
Lateral cutaneous nerves + vessels
Superior neurovasculature supplying skin/cutaneous aspects laterally
*changes planes
Thoracolumbar fascia
Deep fascia - thoracic + lumbar
Medial attachment: nuchal ligament, tips of SPs, supraspinous ligament, median crest of sacrum
Lateral attachment: cervical + lumbar TPs, angles of ribs
Trapezius (origin + insertion)
Origin:
1) SNL
2) EOP
3) Nuchal ligament
4) SPs of C7-T12
Insertion:
1) Spine of scapula
2) Acromion
3) Lateral 1/3 clavicle
Latissimus dorsi (origin + insertion)
Origin:
1) SPs of T6-T12
2) Thoracolumbar fascia
3) Iliac crest
4) Ribs 9/10-12
Insertion:
Floor of intertubercular groove of humerus
Teres major (origin + insertion)
Origin:
1) Inferior part of lateral border of scapula
2) Posterior surface of inferior angle of scapula
Insertion:
Medial lip of intertubercular sulcus of humerus
Trapezius (function + innervation + vascularization)
Function:
1) Upper = elevate scapula + clavicle
2) Middle = retract scapula
3) Lower = depress scapula
4) Upper + Lower = rotate scapula up
* **Helps hold scapula on ribcage
Innervation:
1) Motor = spinal accessory nerve (CN XI)
2) Sensory = C3, C4 (pain + proprioception)
Vascularization:
1) Occipital artery (descending part)
2) Superficial or transverse cervical artery (transverse part)
3) Dorsal scapular artery (ascending part)
Latissimus dorsi (function + innervation + vascularization)
Function:
1) Adduct humerus
2) Extend humerus
3) Medial (internal) rotation of humerus
4) Raises body towards arms (pull-up)
Innervation:
Thoracodorsal (C6, C7) (C8)
*Found near lateral tendon
Vascularization:
1) Thoracodorsal artery
2) Perforating arteries of the 9th-11th posterior intercostal arteries
3) 1st-3rd lumbar arteries
Teres major (function + innervation)
Function:
1) Adduct shoulder joint
2) Medial (internal) rotation of shoulder joint
Innervation:
Lower subscapular nerve (C5) (C6)
Rhomboid major (origin + insertion)
Origin:
SP of T2-T5
Insertion:
Medial border of the scapula from spine to inferior angle
Rhomboid major (function + innervation + vascularization)
Function:
1) Retract scapula
2) Rotate GH cavity inferiorly
3) Fix scapula to thoracic wall
Innervation:
Dorsal scapular nerve (C5) (C4)
Vascularization:
1) Dorsal scapular artery
2) Deep branch of transverse cervical artery
3) Dorsal branch of upper 5 or 6 posterior intercostal arteries
Rhomboid minor (origin + insertion)
Origin:
1) Nuchal ligament
2) Spinous process of C7 and T1
Insertion:
Medial border of the scapula, down to the spine
Rhomboid minor (function + innervation + vascularization)
Function:
1) Retract scapula
2) Rotate GH cavity inf
3) Fix scapula to thoracic wall
Innervation:
Dorsal scapular nerve (C5) (C4)
Vascularization:
1) Dorsal scapular artery
2) Deep branch of transverse cervical artery
3) Dorsal branch of upper 5 or 6 posterior intercostal arteries
Levator scapulae (origin + insertion)
Origin:
Posterior tubercles of TPs of C1-C4
Insertion:
Superior angle of the scapula
Levator scapulae (function + innervation + vascularization)
Function:
Elevate scapula, rotate scapula down, rotate GH cavity inf
Innervation:
Dorsal scapular nerve (C4, C5) + C3, C4 spinal nerves
Vascularization:
Transverse cervical and ascending cervical arteries (branches of the thyrocervical trunk)
Serratus posterior inferior muscles (origin + insertion)
Origin:
Spinous processes of T11-L2
Insertion:
Inferior borders of ribs 8-12 near angles
Serratus posterior superior muscles (function + innervation)
Function:
Elevate ribs
*Serves as retinacula (keeps deep back muscles in place)
Innervation:
Intercostal nerves 2-5
Serratus posterior superior muscles (origin + insertion)
Origin:
1) Nuchal ligament
2) Spinous processes of C7-T3 vertebrae
Insertion:
Superior borders of ribs 2-4
Serratus posterior inferior muscles (function + innervation + vascularization)
Function:
- Depress ribs
- Serves as retinacula (keeps deep back muscles in place)
Innervation:
1) Intercostal nerves 9-11
2) T12 subcostal nerve
Vascularization:
1) Posterior intercostal arteries
2) Subcostal artery & upper lumbar arteries
What common symptom will present if nerves supplying the scapulothoracic stabilizer muscles are injured? What muscles are those?
- Winging scapula
- Involves serratus anterior, trapezius, rhomboids
- Primary - due to dysfunction in scapulothoracic stabilizer muscles
- Secondary - in association w/ other pathologies (subacromial bursitis, GH joint disorders)
- Trapezius helps keep scapula against ribcage
- Typically injured in posterior triangle of the neck (e.g., lymph node dissection, or iatrogenic [surgical] injury)
Types of spinal curvature abnormalities
1) Scoliosis
2) Kyphosis (thoracic)
3) Lordosis (lumbar)
Vertebral body
Round osseous part with flat ends sup + inf.
Separated by IV discs.
Pedicle
“Arms” reaching out from VB.
*Screws go through this to secure VBs.
Articular process
Sup + inf processes that articulate with adjacent VBs
Lamina
Top of arch forming posterior end of vertebral arch, extends from pedicles
Transverse process
Bilateral projections on either side of neural arch that serve as attachment points for muscles
Vertebral notches
Sup + inf, form the IV foramina when joined
Annulus fibrosis
Fibrocartilage rings around circumference of IV disc
Nucleus pulposus
Central core of IV disc that is soft and malleable
*Can herniate into VC + compress SC/nerve roots
Uncovertebral joints
Synovial joints btwn uncus of VB of C3-C6
*Frequent sites of spur formation
C7 landmark
Vertebra prominence
*Most easily palpated
T7 landmark
Inferior angles of scapula
L4 landmark
Iliac crest
Sacral promontory
Sacral landmark on radiographs
*L5 right above
Layers of back
1) Skin
2) Superficial (subcutaneous) fascia
- Aka tela cubcutanea, hypodermis
3) Deep (investing) fascia
4) Muscle
5) Bone
Function of superficial (extrinsic) back muscles
1) Connect upper limb to the trunk
2) Control limb movement
Function of intermediate (extrinsic) back muscles
Serve as retinacula (help hold deeper muscles in place)
*Minor role in respiration
Function of deep (intrinsic) back muscles
1) Control posture
2) Control movements of vertebral column
Scapulohumeral rhythm
Ratio of the glenohumeral movement to the scapulothoracic movement during arm elevation
Superficial fascia
Thin layer of loose fatty connective tissue underlying the dermis and binding it to the parts beneath
Name the superficial (extrinsic) back muscles
1) Trapezius
2) Latissimus dorsi
3) Rhomboid major
4) Rhomboid minor
5) Levator scapulae
What muscle does the spinal accessory nerve innervate?
- Trapezius
- SCM
What muscles does the dorsal scapular nerve innervate?
1) Rhomboid major
2) Rhomboid minor
3) Levator scapulae
What muscle does the thoracodorsal nerve innervate?
- Latissimus dorsi
What muscle helps abduct shoulder joint to 15 degrees?
- Supraspinatus
Name the intermediate extrinsic back muscles
- Serratus posterior superior
- Serratus posterior inferior
