Station 8: The Spine and Nerves Flashcards
What are the ligaments of the spine?
Anterior Longitudinal Ligament (anterior portion of spine)
Posterior Longitudinal Ligament (anterior portion of spine)
Ligamentum flavum (posterior)
Interspinous ligament (posterior
Supraspinous ligament (posterior)
Intertransverse ligament (posterior)
Which ligament bears the greatest strain in hyperextension?
Anterior longitudinal ligament
Which ligament bears the greatest strain in flexion?
Interspinous ligament (more fibres in more directions)
Which ligament bears the greatest strain in lateral flexion?
Contralateral intertransverse ligament
Which ligament bears the greatest strain in rotation?
Capsular ligaments of zygapophyseal joint
What colour is ligamentum flavum and why?
Yellow due to elastin (2:1 ratio of elastin to collagen)
What section of the vertebrae has the most flexion/extension?
L5-S1
What section of the vertebrae has the most lateral flexion?
C3-C5
What section of the vertebrae has the most rotation?
C1-C2
What do characteristics do these points of the vertebrae have?
OC-C1
C1-C2
C2-C7
T1-T12
L1-L5
OC-C1: no rotation (atlanto-occipital)
C1-C2: lots of rotation from the dens. No lateral flexion
C2-C7: Flexion/extension higher from C5 onwards
T1-T12: Frontal facing facets, little flex/ext, good lateral flexion and rotation
L1-L5: great flex/ext up to 20 degrees, minimal rotation
What is the dynamic between erector spinae and Line of Gravity?
LOG pushes us forward, ES counteracts this
What is the ROM for neutral thoracic kyphosis?
20-45 degrees
What is the ROM for thoracic hypokyphosis?
<20 degrees
What is the ROM for thoracic hyperkyphosis?
> 45 degrees
What is the ROM for neutral lumbar lordosis?
20-40 degrees
What is the ROM for lumbar hypolordosis?
<20 degrees
What is the ROM for lumbar hyperlordosis?
> 40 degrees
What does thoracic kyphosis do to the LOG?
Pushes it more forward, and thus ES must work hard to balance the weight which is set forward
What is the ROM for neutral pelvic tilt?
30 degrees
What is the ROM for anterior pelvic tilt? and what is this?
> 30 degrees. Lordosis
What is the ROM for posterior pelvic tilt?
<30 degrees
How you can you position yourself to reduce the load on the lumbar spine?
lie down on back
No gravity
How many cranial nerves are there?
12
How many spinal nerves are there?
31
How many cervical nerves are there and why?
8 cervical nerves because they come out on top of the corresponding bone
From thoracic onwards, where do nerves come out from?
Below the corresponding bone
What is a plexus?
Network or bundle of spinal nerves after they come out of the spinal cord and run into nerves
What is the dorsal nerve root?
Afferent, sensory. So receives the input. On posterior side
What is the ventral nerve root?
Efferent, motor. Sends input to effector. On anterior side
What are the components of a reflex arc?
- Receptor
- Sensory neuron
- Integration centre
- Motor neuron
- Effector
Describe the brachial plexus
Serves the arm
Origin: C5-T1
5 nerves
- Axillary (shoulder)
- Musculocutaneous (bicep area)
- Radial (tricep and forearm)
- Ulnar
- Median (forearm)
Which nerve from the brachial plexus is affected by Saturday night paralysis?
Radial nerve - when arm left in awkward position this nerve gets compressed
Which nerve is the funny bone?
Ulnar - medial epicondyle of humerus. Bone and nerve are exposed
What are some common symptoms of brachial plexus damage?
Arm: adducted, internally rotated
Hand: flexed
Elbow: extended, pronated
Describe the Lumbar Plexus?
Serves lower body
Arises from L2-L4
Lies with iliopsoas (psoas portion)
2 nerves
- Femoral: front upper leg (iliopsoas and quad muscles)
- Obturator: inside of leg (adductors)
If you had pain in the medial thigh, which nerve would be damaged?
Obturator nerve from Lumbar Plexus
Describe the Sacral Plexus
Supplies posterior leg
Arises from L4-S4
2 Nerves
- Sciatic
- Tibial: back of leg
- Common fibular: front of lower leg
- Superior and inferior gluteal (glutes)
What is a dermatome?
Area of skin innervated by a single spinal nerve
