Back Flashcards
Which are key distinguishing features between vertebrae?
Cervical: foramen in transverse process
Thoracic: costal facets
Lumbar: neither
What type of joint is an intervertebral disc?
A secondary cartilaginous joint / symphysis
Upper and lower bodies covered in hyaline cartilage, united by annulus fibrosus.
What are the remnants of the embryonic notochord in the adult body?
The nucleus puloposis and the apical ligament of the atlas
What are the key stabilising ligaments of the sacro-iliac joint?
Opposing gliding movement
- interosseous sacroiliac
- iliolumbar
Opposing forward rotation of sacral promontory
- sacrotuberous
- sacrospinous
From lateral to medial, which structures lie behind rectosacral fascia on the sacrum?
sacral sympathetic trunk
sacral foraminae
median sacral artery
lymph nodes
What is the sequential blood supply of vertebrae from superior to inferior?
- vertebral artery
- ascending cervical
- deep cervical
- posterior intercostal
- lumbar
- lateral sacral arteries
- each give small branches to vertebral bodies
What is the venous drainage of vertebrae?
INTERNAL VERTEBRAL VENOUS PLEXUS
- drains posteiror surface via basivertebral veins
- lies inside vertebral canal outside dura
drains inter external vertebral venous plexus
- drains into vertebral/posterior intercostal/lumbar/lateral sacral veins
- drains into BCV, SVC, IVC, internal iliac
How does malignant disease spread to the spine?
Venous communication with drainage systems with
- renal veins
- azygous (breast and bronchus drainage)
- inferior thyroid
- pelvic visceral veins
valveless path to vertebrae
What are the extrinsic muscles of the back and their actions?
Trapezius: elevates, retracts and depresses scapula
- Accessory Nerve
Latissimus Dorsi: adducts, extends, and internally rotates humerus
- Thoracodorsal Nerve
Rhomboids maj/min: press scapula against thoracic wall
- Dorsal Scapular Nerve
Levator scapularis: elevates scapula
- Dorsal scapular nerve
What are the intermediate muscles of the back and their actions?
Serratus posterior superior: elevates ribs
Serratus posterior inferior: depresses ribs
What are the intrinsic muscles of the back and their actions?
Spinotransversalis
- splenius capitis: retracts head, extends neck, rotates unilaterally
- splenius cervicus
Erector Spinae (lat to med) - iliocostalis - longissimus - spinalis (i long for spinach) primary extensors of vertebral column
Transversospinalis
- semispinalis
- multifidus
- rotatores
What are the principles of innervation for back musculature?
All EXTRINSIC muscles innervated by VENTRAL rami because muscles insert onto the UPPER LIMBS
All INTRINSIC muscles innervated by DORSAL rami because they are limited to the SPINE
What are the origins and insertions of the trapezius?
- medial 3/4 superior nuchal line to spine of C7 vertebra along ligamentum nuchae, extending to spinous processes/supraspinous ligaments of all T vertebrae
- occipital fibres insert into lateral 1/3 clavicle
- fibres insert along medial border acromion, superior and medial lip of scapular spine
What is the nerve supply to trapezius?
Spinal part of accessory nerve
- C1-5/6
Branches from Cervical plexus (proprioception)
- C3/4
What is the origin/insertion of latissimus dorsi?
- T7 spine, supraspinous ligaments of al llumbar and sacral vertebrae
- posterior crest of ilium
- a few fibres from apex of scapula
- lower 4 ribs interdigitating with external oblique
- inserts into floor of intertubercular groove
