Anatomy back Flashcards
Where are the spinal cord enlargements located
During the course of the spinal cord, there are two points of enlargement. The cervical enlargement is located proximally, at the C4-T1 level. It represents the origin of the brachial plexus. Between T11 and L1 is the lumbar enlargement, representing the origin of the lumbar and sacral plexi.
Where does the artery of adam originate
Significant anatomical variation but normally arises from left posterior branch of the intercostal artery, which itself arises from the aorta
Why is the mechanism of injury important in central cord syndrome
Complete cord syndrome, the corticospinal tract for the UL runs centrally than the lower limb and hence these are affected more. Common in hyper-extension injuries.
In old patients, osteophytes on the vertebral bodies may exacerbate these symptoms
Layers encountered in ACDF
Skin, subcutaneous fascia, platysma, investing fascia, , carotid sheath, pre-tracheal fascia, pre-vertebral fascia
Describe the structure of the intervertebral disc
Nucleus pulposus on the inside which is type 2 collagen (embryonic remnant of the notochord) and annulus fibrosis that is type 1 collagen
What type of joint is an intervertebral joint
Secondary cartilagenous joint.
What are the common sites of disc prolapse
C5/C6, C6/C7, L4/L5, L5/S1
Prolapse of what discs will cause cauda equina
Anything posteriorly below level of L1 and L2
Anterior cord syndrome
Most common type of spinal injury, caused by interruption of the anterior spinal arteries. Loss of power below the lesion and loss of pain and temperature sensation below the lesion
The lower extremities is more commonly affected than the supper extremities and the prognosis is poor, with power and sensation only coming back in about 10-20% of patients
Describe the vertebral arteries
The left is normally larger than the right and carries more blood
1st part runs in front of C7
2nd part runs in C2-C6 transverse foramen
3rd part passes through the C1 transverse formaina
4th part through dura mater and anterior part of medulla oblongata
They join to form the basilar artery
What are the branches of the subclavian artery
VIT C D
1st part vertebral artery, internal mammary and thyrocervical trunk
2nd part: costocervical trunk
3rd part: Dorsal scapular artery
The subclavian artery becomes the axillary artery at the lateral border of the first rib
What vertebrae have transverse foramina
The cervical
What are the structures that pass through the transverse foramina
Vertebral artery, vein and sympathetic plexus
What are the characteristic features of different vertebrae
Cervical: Small bodies, bifid spinous process apart from C6 and C7, Large triangular vertebral foramen and transverse foramin
Thoracic: Heart shaped bodies with long spinous processes pointing inferiorly. Facet joints for attachments with ribs. Small circular vertebral foramina
Lumbar: Large kidney shaped vertebral bodies. Triangular vertebral foramina, Long, thin transverse process, bulky and square spinous process.
Sacral: Fused vertebral bodies and sacral foramina.
What is the significance of the posterior longitudinal ligament attaching to the intervertebral discs?
Reinforces the posterior aspect of the IVD. However, it is thinner on the lateral side and hence most discs will herniate posteriolaterally
