Anatomy 2: Back, Spine and Spinal Cord Flashcards
What vertebrae can be palpated first on the back?
T1 spinous process
What do skin dimples on the lower back represent?
PSIS
What are the three parts of the trapezius, relative to their position on the back?
Descending (superior)
Transverse (middle)
Ascending (inferior)
Which rotator cuff muscle can be palpated on the back?
Teres major
Which muscle may be affected in lower back pain?
Erector spinae
What are the extrinsic back muscles (top - bottom), and what do they attach to?
Levator scapulae Rhomboid major and minor Trapezius Latissimus dorsi PECTORAL GIRDLE
What is the function of the extrinsic back muscles?
Move upper limb
What is the function of the intrinsic back muscles?
Maintain posture and extend the spine (ES) or rotate the spine (TVSPS)
What is the main superficial intrinsic back muscle? Where does it attach inferiorly?
Erector spinae
Common tendon to sacrum and iliac crest
What are the divisions of the erector spinae, and thus where do they attach superiorly?
Rib (Costalis)
Transverse process of vertebra (Longus)
Spinous process of vertebra (Spinous)
What is the main deep intrinsic back muscle? Where is it located?
Transversospinalis
Within grooves between transverse and spinous processes
Where do the muscle fibres of transversospinalis attach between?
Vertebra and skull
Vertebra and rib
One vertebra and another
Sacrum and vertebra
What is the nerve supply to the back muscles?
Segmental (as per dermatome/ myotome)
Via posterior ramii branches (cervical , thoracic, lumbar)
What muscles lie laterally to the vertebral column?
MUSCLES OF POSTERIOR ABDO WALL
Psoas major
Quadratus lomborum
What muscles lie posterally to the vertebral column?
INTRINSIC BACK MUSCLES
Transversospinalis
Erector spinae
What muscles lie laterally to the posterior abdominal wall muscles?
MUSCLE OF UL Latissimus dorsi MUSCLES OF ANTEROLATERAL ABDO WALL Transverse abdominus Internal oblique External oblique
If the erector spinae muscle contracts bilaterally the spine will undergo…
Extension
If the erector spinae muscle contracts unilaterally the spine will undergo …
Lateral flexion
What muscles control flexion of the spine?
Rectus abdominus
Psoas major
How many vertebrae are there in the adult vertebral column?
33
How are the vertebrae divided?
7 cervical (C1 - C8) 12 thoracic (T1 - T12) 5 lumbar (L1 - L5) 5 sacral (1 sacrum) 4 coccygeal (1 coccyx)
What are the 3 functions of the vertebrae?
Support head and trunk when upright
Protect spinal cord and nerves
Allow movement of head on neck and trunk
What are the main curvatures of the spine and are they primary or secondary?
Cervical lordosis (2) Lumbar lordosis (2) Thoracic kyphosis (1) Sacral kyphosis (1)
What curvature pathology is caused by excessive anterior weight e.g. in pregnancy or obesity?
Excessive lumbar lordosis
What curvature pathology is caused by old age typically?
Excessive thoracic kyphosis
List the parts of a vertebra
Spinous process x 1
Transverse process x 2
Inferior and superior articular processes x 4
Vertebral foramen
Vertebral body
Vertebral arch (made up of 2 x pedicle (superior) and 2 x lamina)
What type of joint is the articulation between articular processes and adjacent vertebrae?
Synovial facet joint
Which structure contains and protects the spinal cord and nerves?
Intervertebral foramen
What joints are affected in arthritis of the spine?
Facet joint
Where are IV discs found? What are they at risk of?
Between adjacent vertebral bodies
Disc herniation
Where is there an abscence of IV discs?
Between C1 and C2
Describe the structure of an IV disc
Outer fibrous ring - annulus fibrosis
Inner soft pulp - nucleus pulposis
Which short ligament connects the adjacent lamina posteriorly to the spinal cord?
Ligamentum flavum
What is the function of the posterior longitudinal ligament?
Narrow and weak
Prevents overflexion
What is the function of the anterior longitudinal ligament?
Broad and strong
Prevents overextension
What is the function of the supraspinous ligaments?
Strong, fibrous
Connects tips of spinous processes
What is the function of the interspinous ligaments?
Weak, membranous
Connect superior and inferior parts of adjacent spinous processes
List the ligaments of the vertebral column
Ligamentum flavum Posterior longitudinal ligament Anterior longitudinal ligament Supraspinous ligaments Interspinous ligaments
Which vertebra are classed as atypical and why?
C1: ATLAS - no body or spinous process - A + P arch instead
C2: AXIS - odontoid process, which projects superiorly from body
C7: VERTEBRA PROMINENS - 1st palpable spinous process
Which ligament connects C1 and C2 vertebra?
Transverse ligament
Where does the atlanto-occipital joint connect?
Between occipital condyles of C1 and superior articular facets of atlas
What type of joint is the atlanto-occipital joint? What is it’s function?
Synovial joint
Flexion and extension of neck (yes, no)
Some lateral flexion and rotation
Where does the atlanto-axial joint connect?
3 articulations
2 x inferior articular facets of atlas and superior articular facets of axis
1 x anterior arch of atlas and odontoid process of axis
What is the main role of the atlanto-axial joint?
Rotation
What are the names given to the area at the top and bottom of the sacral canal?
Sacral promontory
Sacral hiatus
What are commonly classed as the ‘wings’ of the sacrum?
Left and right ala
What exists within the sacral canal?
Cauda equina
Meninges
Which part of the sacrum is palpable?
Sacral hiatus
Which part of the sacrum is caudal anaesthesia inserted into to anaesthetise sacral spinal roots?
Sacral hiatus
Where does the spinal cord start and end?
Foramen magnum (C1) Vertebral level L1/L2 (Co1 segment)
What is the cauda equina?
All spinal nerve routes from L2 to Co that have descended to numbered vertebra where the spinal nerve is in IV foramen
What is the spinal cord surrounded by?
3 layers of meninges (dura, arachnoid matter, pia) Epidural fat (and venous plexuses)
What is a laminectomy?
Removal of 1 or more spinous processes and adjacent lamina to relieve pressure on the spinal cord/ nerve roots
