Unit 1 - III. Vertebral Column / Spinal Column Flashcards
1
Q
What is the number of vertebrae in a typical adolescent?
A
33 segments
2
Q
What is the number of vertebrae in a typical adult?
A
26 segments
3
Q
What is the number of vertebrae in the typical spine?
A
24 segments
4
Q
What constitutes the spine?
A
the 24 presacral segments; the cervical, thoracic and lumbar vertebrae
5
Q
How many segments unite to form the typical sacrum?
A
5 segments
6
Q
How many segments unite to form the typical coccyx?
A
4 segments
7
Q
What does the term “cervical” refer to?
A
the region of the neck
8
Q
What is the typical number of segments in the cervical region?
A
7 segments
9
Q
What does the term “thoracic” refer to?
A
breast plate or chest; it referred to the armor bearing region of the torso
10
Q
What other term is often used to identify the vertebral segments of the chest?
A
the dorsal segments; the dorsals
11
Q
What is the typical number of segments in the dorsal or thoracic region?
A
12 segments
12
Q
What does the term “lumbar” refer to?
A
the loin; the region between the rib and the hip
13
Q
What is the typical number of segments in the lumbar region?
A
5 segments
14
Q
What does the term “sacrum” refer to?
A
the holy bone or holy region
15
Q
What does the term “coccyx” refer to?
A
a cuckoo birds’ bill or cuckoo birds’ beak
16
Q
Which region of the spine is more stable in terms of the number of segments/vertebrae?
A
the cervical region
17
Q
Which variations account for the disparity in number and morphology of vertebrae within the population?
A
sexual dimorphism or gender variation, ontogenetic variation (growth variation or age variation), geographic variation or population-based variation, and idiosyncratic variation (individual variation)
18
Q
What is the length of a typical male spinal column?
A
about 70 centimeters or 28 inches
19
Q
What is the length of a typical female spinal column?
A
about 60 centimeters or 25 inches
20
Q
What is the difference in length between a typical male and typical female spinal column?
A
about 3 inches
21
Q
What is the length of the male cervical region (both measurements)?
A
about 12 centimeters or 5 inches
22
Q
What is the length of the male thoracic region (both measurements)?
A
about 28 centimeters or 11 inches
23
Q
What is the length of the male lumbar region (both measurements)?
A
about 18 centimeters or 7 inches
24
Q
What is the length of the male sacrum (both measurements)?
A
about 12 centimeters or 5 inches
25
Based on the numbers for individual regions of the vertebral column, what is the length of the male spine (both measurements)?
about 58 centimeters or 23 inches
26
How does the vertebral column participate in protection of neural tissues?
the spinal cord and beginning PNS are located within the vertebral segments
27
How does the vertebral column participate in protection of the viscera?
ribs are attached to vertebrae to form the thorax thus protecting the heart and lungs
28
What parts of the body are supported by the vertebral column?
the head, upper extremities, ribs, viscera, and pelvis
29
How does the vertebral column participate in skeletal formation?
ribs are formed from the costal process of the embryonic vertebral template
30
What levels of the vertebral column specifically accommodate weight-bearing transfer?
S1-S3 at the auricular surface
31
Distinguish between motion and locomotion.
motion is movement without travel; locomotion is movement to a new site or location
32
What is specifically responsible for shape and position of the human frame?
comparative anterior vs. posterior height of the vertebral body and comparative anterior vs. posterior height of the intervertebral disc
33
How does the vertebral column accommodate transmission?
the peripheral nerve communicates with the central nerve system via the intervertebral foramen
34
What organ(s) is (are) specifically associated with the horizontal axis of the skull?
the eye and the vestibular apparatus of the inner ear
35
How is the vertebral column involved in stabilization of visceral function?
integrity of the spinal column enhances appropriate nerve system control of viscera
36
When does the embryonic disc form?
second week in utero
37
When does gastrulation occur or a 3-layered embryo form?
third week in utero
38
What are the 3 layers of the embryo called?
ectoderm, mesoderm, endoderm
39
Invagination of ectoderm along the primitive streak gives rise to what embryonic structure?
notochord
40
What is the name given to the mesoderm that will give rise to the vertebral column?
paraxial mesoderm
41
What does paraxial mesoderm give rise to that will form the vertebral column?
somites
42
Name the areas of cellular differentiation formed within the somite.
sclerotome, myotome and dermatome
43
What part of the somite will give rise to the vertebral column?
sclerotome
44
List, in order, the names of the succesive vertebral columns formed during development?
membranous, cartilaginous, skeletal or osseous
45
Migration of sclerotomes to surround the notochord forms what developmental feature?
the perichordal blastema
46
The perichordal blastema gives rise to what processes?
neural processes and costal processes
47
What is the name of the artery located between adjacent perichordal blastemae?
intersegmental artery
48
Cell proliferation within the perichordal blastema will result in what features?
a loose cranial sclerotomite and a dense caudal sclerotomite
49
What forms between the sclerotomites of a perichordal blastema?
the intrasclerotomal fissure (fissure of von Ebner)
50
The intrasclerotomal fissure (fissure von Ebner) gives rise to what developmental feature?
the perichordal disc
51
The perichordal disc is in the presumptive location of what adult feature?
the intervertebral disc
52
What is the earliest embryonic feature that will identify the position of the adult intervertebral disc?
the intrasclerotomal fissure (fissure of von Ebner)
53
The union of a dense caudal sclerotomite and a loose cranial sclerotomite from adjacent perichordal blastemae gives rise to what feature?
the vertebral blastema
54
What vessel will be identified adjacent to the vertebral blastema?
the segmental artery
55
When will cartilage first form in the membranous vertebral blastema?
beginning in the 6th embryonic week
56
What is the name given to the replacement of mesoderm by cartilage?
chondrification
57
Chondrification is first identified in which region of the embryonic vertebral column?
the cervical region
58
What are the names given to the centers of chondrification within the vertebral blastema?
centrum center, neural arch center, transverse process center
59
How many centers of chondrification typically appear in the vertebral blastema?
six... 2 for the centrum, 2 for the neural arch, 2 for each transverse process
60
What is the earliest time that centers of ossification appear in the cartilaginous vertebra?
during the 7th embryonic week
61
Ossification begins in which region of the embryonic vertebral column?
the lower cervical-upper thoracic region
62
What is the name given to centers of ossification based on time of appearance?
primary centers appear in utero, secondary centers appear after birth
63
What is the name given to centers of ossification appearing in utero?
primary centers
64
What is the name given to centers of ossification appearing after birth?
secondary centers
65
What is the ratio of primary to secondary centers of ossification for a typical vertebra?
3 primary centers: 5 secondary centers
66
What are the names of the primary centers of ossification for a typical vertebra?
centrum centers and neural arch centers
67
How many primary centers of ossification appear in the typical vertebra?
three... 1 for the centrum, 2 for the neural arches
68
What is the classification of the joint forming between primary centers of ossification?
cartilage synchondrosis / amphiarthrosis synchondrosis
69
What are the names of the synchondroses forming between primary centers of ossification in the typical vertebra?
neurocentral synchondrosis and neural arch synchondrosis
70
What are the names of the five secondary centers of ossification for a typical vertebra?
tip of the transverse process, tip of the spinous process, epiphyseal plate centers
71
How many secondary centers of ossification appear in the typical vertebra?
five... 1 for the tip of each transverse process, 1 for the tip of the spinous process, 1 for each epiphyseal plate
72
What is the classification of the joint forming between secondary centers of ossification and the rest of the typical vertebra?
cartilage synchondrosis / amphiarthrosis synchondrosis
73
What are the names of the synchondroses forming between secondary centers of ossification and the rest of the typical vertebra?
tip of the transverse process synchondrosis, tip of the spinous process synchondrosis, and epiphyseal ring synchondrosis
74
What is the range of appearance for secondary centers of ossification of a typical vertebra?
during puberty, typically ages 11-16 years old
75
What are the three basic osseous parts of a vertebra?
the vertebral body, vertebral arch, and the apophyseal regions
76
What is formed by the vertebral body and vertebral arch?
the vertebral foramen
77
What is the general shape of the vertebral body at each region of the spine?
cervical - rectangular; thoracic - triangular; lumbar - reniform
78
What is the name given to the compact bone at the superior and inferior surfaces of the vertebral body?
superior epiphyseal rim, inferior epiphyseal rim
79
What is the central region at the superior and inferior surfaces of the vertebral body called?
cancellous or spongy bone
80
What is the name given to the cartilage found at the superior and inferior surface of a developing vertebral body?
superior epiphyseal plate, inferior epiphyseal plate
81
What are the names of the openings found around the margins of the vertebral body?
nutrient foramina or vascular foramina
82
What large opening is usually observed at the back of the vertebral body?
the basivertebral venous foramen
83
What is the name of the vessel entering the nutrient or vascular foramen?
osseous artery
84
What is the name given to the large vessel exiting the back of the vertebral body?
the basivertebral vein
85
What is the semicircular region of bone attached to the back of the vertebral body called?
the vertebral arch
86
What is the name given to the anterior part of the vertebral arch?
the pedicle
87
What is the name given to the posterior part of the vertebral arch?
the lamina
88
What is the name given to the intermediate part of the vertebral arch where the transverse process and articular processes attach?
the lamina-pedicle junction
89
What is the name of the feature located at the upper and lower surfaces of the pedicle?
the superior vertebral notch or superior vertebral incisure; the inferior vertebral notch or inferior vertebral incisure
90
What is the generic orientation of the pedicle at each region of the spine?
cervical - posterolateral
thoracic - posterior, slight lateral
lumbar - posterior
91
All lamina are oriented in what direction?
posterior and median
92
What is the name given to the overlap of laminae seen on X-ray?
shingling
93
What ligament will attach to the lamina?
the ligamentum flavum
94
What is the name given to abnormal bone at the attachment site of the ligamentum flavum?
para-articular process
95
What classification of bone will para-articular processes represent?
accessory bone
96
What is the name given to the lamina - pedicle junction at each region of the spine?
cervical - articular pillar; thoracic and lumbar - pars interarticularis
97
What is the name given to the junction of the vertebral arch - spinous process on lateral X-ray?
the spinolaminar junction
98
What is the name to the tubular bone growth regions of the vertebral arch?
the apophyseal regions
99
What names may be given to each apophysis of the spine?
the transverse apophysis or transverse process; articular apophysis or articular process; spinous apophysis or spinous process
100
What is the generic orientation of the transverse process or transverse apophysis at each region of the spine?
cervical - anterolateral; thoracic - posterolateral; lumbar - lateral
101
All non-rib-bearing vertebra of the spine retain what equivalent feature?
the costal element
102
What is the name given to the rounded elevation at the end of the transverse apophysis or transverse process?
the transverse tubercle
103
What will cause the transverse process/transverse apophysis to alter its initial direction in the cervical region?
cervical spinal nerves are pulled forward and downward to form the cervical and brachial nerve plexuses thus remodeling the transverse process to accommodate their new position
104
What will cause the transverse process/transverse apophysis to alter its initial direction in the thoracic region?
the growth of the lungs remodel the shape of the ribs which in turn push the transverse processes backward
105
What will the articular process/articular apophysis support?
the articular facet
106
What is the name given to the joint formed between articular facets of a vertebral couple?
the zygapophysis
107
What is the name given to the bone surface at the front of a zygapophysis?
the superior articular facet
108
What is the name given to the bone surface at the back of a zygapophysis?
the inferior articular facet
109
What names are given to the part of the vertebra which supports the front of the zygapophysis?
the superior articular apophysis, the superior articular process, or the pre-zygapophysis
110
What names are given to the part of the vertebra which supports the back of the zygapophysis?
the inferior articular apophysis, the inferior articular process, or the post-zygapophysis
111
In the vertebral couple, the part of the vertebra which lies anterior to the zygapophysis is called the ___.
pre-zygapophysis
112
In the vertebral couple, the part of the vertebra which lies posterior to the zygapophysis is called the ___.
post-zygapophysis
113
What is the name given to the part of the vertebra forming the pre-zygapophysis?
the superior articular process or superior articular apophysis
114
What is the name given to the part of the vertebra forming the post-zygapophysis?
the inferior articular process or inferior articular apophysis
115
What is the method of calculating the angle of the spinous process/spinous apophysis?
calculate the angle formed between the undersurface of the spinous process/spinous apophysis and the horizontal plane
116
What is the name given to the normal overlap of spinous processes or spinous apophyses as seen on X-ray?
imbrication
117
What is the name given to the rounded elevation at the tip of the spinous process/spinous apophysis?
the spinous tubercle
118
What is the orientation of the spinous process/spinous apophysis at each region of the spine?
cervical - slight angle inferiorly
thoracic - noticeable angle inferiorly
lumbar - no inferior angle
119
What will form the posterior boundary of a typical intervertebral foramen?
the inferior articular process/post-zygapophysis, the superior articular process/pre-zygapophysis, the capsular ligament, and the ligamentum flavum
120
What will form the superior boundary of a typical intervertebral foramen?
the inferior vertebral notch or inferior vertebral incisure
121
What will form the inferior boundary of a typical intervertebral?
the superior vertebral notch or superior vertebral incisure
122
What will form the anterior boundary of a typical intervertebral foramen?
the vertebral body of the segment above, the vertebral body of the segment below, the intervertebral disc, and the posterior longitudinal ligament
123
What name is given to the opening located withing the vertebral body - vertebral arch enclosure?
the vertebral foramen
124
The union of all vertebral foramina forms an apparent vertical cylinder called the ___.
the vertebral canal or spinal canal
125
What neural structures will occupy the vertebral foramen until the level of L2?
the spinal cord/spinal medulla/medulla spinalis, the proximal part of the peripheral nerve system, and the meninges
126
What is the typical shape/outline of the vertebral foramen at each region of the spinal column/vertebral column?
cervical - triangular; thoracic - oval; lumbar - triangular; sacrum - triangular
127
At what vertebral level will the spinal cord typically terminate?
L1
128
At what vertebral level will the dural sac typically terminate?
S2
129
What are the segmental arteries?
the arteries whose branches supply the vertebra or segment
130
What segmental arteries arise from the subclavian artery?
the vertebral, thyrocervical trunk and costocervical trunk
131
Which of the segmental arteries will arise from the thyrocervical trunk?
ascending cervical artery
132
Which of the segmental arteries will arise from the costocervical trunk?
deep cervical artery and superior (highest) intercostal artery
133
Which of the segmental arteries will arise from the thoracic descending aorta?
posterior intercostal artery and subcostal artery
134
Which of the segmental arteries will arise from the abdominal descending aorta?
lumbar artery and median (middle) sacral artery
135
Which of the segmental arteries will arise from the internal iliac artery?
the iliolumbar and lateral sacral arteries
136
Identify all segmental arteries of the vertebral column.
vertebral, ascending cervical, deep cervical, superior (highest) intercostal, posterior intercostal, subcostal, lumbar, iliolumbar, lateral sacral and median (middle) sacral
137
What are the segmental arteries of the cervical spine?
the vertebral artery, ascending cervical artery and deep cervical artery
138
What are the segmental arteries of the thoracic spine?
the deep cervical artery, superior (highest) intercostal artery, posterior intercostal artery and subcostal artery
139
What are the segmental arteries of the lumbar spine?
the lumbar arteries, iliolumbar artery, lateral sacral artery and median (middle) sacral artery
140
What are the segmental arteries of the fifth lumbar vertebra?
the iliolumbar artery, lateral sacral artery and median (middle) sacral artery
141
What are the segmental arteries of the sacrum?
the iliolumbar artery, lateral sacral artery and median (middle) sacral artery
142
What segmental levels are supplied by the vertebral artery?
C1-C6
143
What segmental levels are supplied by the ascending cervical artery?
C1-C6
144
What segmental levels are supplied by the deep cervical artery?
C7-T1
145
What segmental levels are supplied by the superior (highest) intercostal artery?
T1,T2
146
What segmental levels are supplied by the posterior intercostal artery?
T3-T11
147
What segmental level(s) is/are supplied by the subcostal artery?
T12
148
What segmental levels are supplied by the lumbar arteries?
L1-L4
149
What segmental levels are supplied by the median (middle) sacral artery?
L5, S1-S5 and coccyx
150
What segmental levels are supplied by the iliolumbar artery?
L5, S1-S5 and coccyx
151
What segmental level(s) is/are supplied by the lateral sacral artery?
L5, S1-S5 and coccyx
152
Which vertebra has the greatest number of segmental arteries associated with it?
L5
153
What are the segmental arteries for L5?
iliolumbar artery, median (middle) sacral artery and lateral sacral artery
154
What branch of the segmental artery supplies the vertebra and the paravertebral region?
dorsospinal artery
155
Which artery is primarily observed in the distal part of the intervertebral foramen?
spinal artery
156
Which branch of the dorsospinal artery will penetrate the meninges to enter subarachnoid space?
spinal artery
157
What are the branches of the spinal artery?
osseous arteries, anterior spinal canal artery, posterior spinal canal artery, anterior medullary feeder artery, posterior medullary feeder artery, anterior radicular artery, posterior radicular artery
158
Which branches of the spinal artery supply the contents of the epidural space?
osseous arteries, anterior spinal canal artery, posterior spinal canal artery
159
What arteries are observed in the epidural space near the posterior longitudinal ligament?
anterior spinal canal artery & plexus
160
What arteries are observed in the epidural space near the ligamentum flavum?
posterior spinal canal artery & plexus
161
Which branches of the spinal artery supply the contents of the subarachnoid space?
anterior radicular artery, posterior radicular artery, anterior medullary feeder artery, posterior medullary feeder artery
162
Which vessel will supply the ventral/anterior nerve rootlet and nerve root?
anterior radicular artery
163
Which vessel will supply the dorsal/posterior nerve rootlets, nerve root and nerve root ganglion?
posterior radicular artery
164
Which artery is now said to enlarge and form the medullary feeder artery?
the radicular artery
165
What is the location and number of medullary feeder arteries present in the adult?
9 anterior and 12 posterior medullary feeder arteries
166
What is the name given to the artery that lies in front of the spinal cord along its length?
anterior spinal artery
167
The anterior spinal artery is a branch of which artery?
the vertebral artery
168
Is the anterior spinal artery a single, continuous artery along the spinal cord?
no
169
As the anterior spinal artery continues along the spinal cord, which arteries unite along its length to give the appearance of a single continuous vessel?
anterior medullary feeder arteries
170
The posterior spinal artery is a branch of which artery?
the posterior inferior cerebellar artery
171
What is the position of the posterior spinal artery relative to the spinal cord?
it lies in the posterolateral sulcus along the spinal cord
172
Is the posterior spinal artery a single, continuous artery the spinal cord?
no
173
As the posterior spinal artery continues along the spinal cord, which arteries unite along its length to give the appearance of a single continuous vessel?
posterior medullary feeder arteries
174
What forms the arterial vasa corona?
anterior spinal arteries, posterior spinal arteries and communicating arteries
175
What is the generic name given to arteries that penetrate the spinal cord?
intramedullary arteries
176
What are the intramedullary branches of the arterial vasa corona?
pial perforating arteries and central/ventral/sulcal perforating arteries
177
What artery gives off the ventral/central/sulcal perforating arteries?
anterior spinal artery
178
What arterial vasa corona branches suppy gray matter and most of the spinal cord?
ventral/central/sulcal perforating arteries
179
What intramedullary branches supply about one third of the spinal cord?
pial perforating arteries
180
What is the source for pial perforating arteries?
the pial plexus
181
What arteries form the pial plexus?
the posterior spinal arteries and the communicating arteries
182
What arteries are responsible for supplementing the arterial vasa corona along the cord?
anterior medullary feeders and posterior medullary feeders
183
What vessels drain the spinal cord?
pial veins
184
What will pial veins drain into?
venous vasa corona
185
Which vessels form the venous vasa corona?
anterior longitudinal veins, posterior longitudinal veins, and communicating veins
186
Which vessels will drain the venous vasa corona?
anterior medullary veins, posterior medullary veins
187
Which vessels will drain the ventral/anterior nerve roots?
anterior radicular veins
188
Which vessels will drain the dorsal/posterior nerve roots?
posterior radicular veins
189
What vessel will drain the dorsal/posterior nerve root ganglion?
posterior radicular veins
190
What veins will lie in the subarachnoid space?
pial veins, venous vasa corona, anterior longitudinal veins, posterior longitudinal veins, communicating veins, anterior medullary veins, posterior medullary veins, anterior radicular veins, posterior radicular veins
191
What veins are observed in the epidural space near the posterior longitudinal ligament?
anterior internal vertebral venous plexus, basivertebral vein
192
What lumenal feature of the anterior internal vertebral venous plexus vessels may function like valves of typical veins?
trabeculae
193
What veins are observed in the epidural space near the ligamentum flavum?
posterior internal vertebral venous plexus
194
What venous vessels are identified in the intervertebral foramen?
intervertebral veins
195
What is the unique feature of veins along the spinal canal?
they lack the bicuspid valve of typical veins
196
Identify the meninges of the spinal cord (spinal medulla or medulla spinalis).
dura mater, arachnoid mater, pia mater
197
Identify the meninges of the spinal cord (spinal medulla or medulla spinalis) and the commonly accepted meaning of each.
dura mater - tough mother; arachnoid mater - spider mother; pia mater - tender or delicate mother
198
Name and locate each space formed between the osseous vertebral foramen and the spinal cord (spinal medulla or medulla spinalis).
epidural space - between the vertebral foramen and the dura mater
subdural space - between the dura mater and the arachnoid mater
subarachnoid space - between the arachnoid mater and the pia mater
199
What is the name given to the fluid within the epidural space?
interstitial fluid
200
What are the vascular contents of the epidural space?
anterior and posterior spinal canal artery & plexus
anterior and posterior internal vertebral venous plexus
basivertebral vein
201
What are the neural contents of the epidural space?
recurrent meningeal/sinu-vertebral/sinus vertebral nerve
202
What ligaments are associated with the epidural space?
Hofmann/anterior dural/meningovertebral ligaments
ligamentum flavum
posterior longitudinal ligament
203
Which of the blood vessels of the epidural space will be found near the vertebral body?
anterior spinal canal artery & plexus
anterior internal vertebral venous plexus
basivertebral vein
204
Which of the nerves of the epidural space will be found near the vertebral body?
recurrent meningeal/sinu-vertebral, sinus vertebral nerve
205
Which of the ligaments of the epidural space will be found near the vertebral body?
posterior longitudinal ligament and Hofmann/anterior dural/meningovertebral ligaments
206
Which of the blood vessels of the epidural space sill be found near the lamina?
posterior spinal canal artery & plexus
| posterior internal vertebral venous plexus
207
Which of the nerves of the epidural space will be found near the lamina?
recurrent meningeal/sinu-vertebral, sinus vertebral nerve
208
Which of the ligaments of the epidural space will be found near the lamina?
ligamentum flavum and Hofmann/anterior dural/meningovertebral ligaments
209
Which meningeal space is now thought to be a potential space, not an actual space?
subdural space - between the dura mater and the arachnoid mater
210
Which of the contents of the epidural space are more likely located near or around the posterior longitudinal ligament?
anterior spinal canal artery & plexus
anterior internal vertebral venous plexus
basivertebral vein
recurrent meningeal/sinu-vertebral/sinus vertebral nerve
Hofmann/anterior dural/meningovertebral ligaments
211
Which of the contents of the epidural space will be found near the lamina?
posterior spinal canal artery & plexus
posterior internal vertebral venous plexus
ligamentum flavum
recurrent meningeal/sinu-vertebral/sinus vertebral nerve
Hofmann/anterior dural/meningovertebral ligaments
212
What is the name given to the fluid present within the subdural space?
serous fluid
213
What is the name given to the fluid within the subarachnoid space?
cerebrospinal fluid
214
What arteries may be present in the subarachnoid space down to the level C3?
```
anterior spinal arteries
communicating arteries
pial perforating arteries
anterior radicular arteries
anterior medullary feeder arteries
posterior spinal arteries
arterial vasa corona
central/sulcal perforating arteries
posterior radicular arteries
posterior medullary feeder arteries
```
215
What veins may be present in the subarachnoid space down to the level C3?
```
pial veins
posterior longitudinal veins
venous vasa corona
posterior radicular veins
posterior medullary veins
anterior longitudinal vein
communicating veins
anterior radicular veins
anterior medullary veins
intervertebral veins
```
216
What ligaments may be present in the subarachnoid space?
dentate/denticulate ligament
217
What contents of the subarachnoid space are changed below the level C6?
the arterial vasa corona consists of 1 anterior spinal artery, 2 posterior spinal arteries and 3 communicating arteries
218
What is the name given to the lateral extension of pia mater along the spinal cord?
dentate (denticulate) ligament
219
What is the unique feature of veins along the spinal canal?
they lack the bicuspid valve of typical veins
220
In horizontal view, what direction of the spinal cord tends to be largest?
transverse
221
What are the spinal cord enlargement locations and the name given to each?
C3-T1, the cervical enlargement; T9-T12, the lumbar (lumbosacral) enlargement
222
Where is the greatest transverse diameter of the spinal cord?
C6
223
In which plane (or direction) will the diameter of the spinal cord decrease from C2 down to T1?
midsagittal or anterior-posterior plane
224
What spinal nerves originate from the lumbar (lumbosacral) enlargement?
L1-S3 spinal nerves
225
What is a generic cord level of origin - vertebral level combination for the lumbar (lumbosacral) enlargement?
L1, L2 cord levels in T9 vertebra; L3, L4 cord levels in T10 vertebra; L5, S1 cord levels in T11 vertebra; S2, S3 cord levels in T12 vertebra
226
What is the caudal end of the spinal cord called?
conus medullaris
227
What spinal nerves originate from the conus medullaris?
typically S4, S5, and Co1
228
In which vertebral foramen will the conus medullaris typically be observed?
L1
229
What is the name given to the nerve roots below L1?
cauda equina
230
What is the continuation of pia mater below the conus medullaris called?
filum terminale internum
231
What is the location and name given to the area where all meninges first converge at the caudal part of the vertebral column?
typically S2, the dural cul de sac
232
Neural tissue has been identified in what part of the filum terminale?
proximal part of the filum terminale internum
233
What is the fate of the neural tissue identified along the filum terminale internum?
it joins peripheral nerve roots of spinal nerves as high as L3 and as low as S4
234
What does the neural tissue associated with the filum terminale externum appear to innervate?
lower limbs and the external anal sphincter
235
The last arterial vasa corona creates creates what feature on angiogram?
cruciate anastomosis
236
What is the name given to the condensation of meninges below S2?
filum terminale externum
237
What is the name given to the caudal attachment of the meninges?
coccygeal medullary vestige
238
What is the name given to the condition in which the conus medullaris is located below L1 and the filum terminale is thickened?
tethered cord syndrome
239
What is the relationship between scoliosis and tethered cord syndrome?
it is suggested that the column will change normal curvatures to mitigate damage to the spinal cord caused by a tethered cord
240
At the intervertebral foramen, what is the relationship between spinal nerve number and vertebral number along the cervical spine?
in the cervical spine, spinal nerves exit above the segment they are numbered after (C8 nerve is the exception to this rule). C3 nerve exits above C3 or between C2/C3
241
At the intervertebral foramen, what is the relationship between spinal nerve number and vertebral number along the thoracic and lumbar spine and the sacrum?
in the thoracic and lumbar spine and for the sacrum, spinal nerves exit below the segment they are numbered after (Co1 nerve is the exception to this rule). T6 nerve exits below T6 or between T6/T7
242
What is the relationship between rib number and vertebral numbers at the costocentral joint?
rib number always equates to same vertebral number at the costocentral joint
rib 3 articulates with T3 segment and also with the T2 segment; only ribs 1,11, and 12 typically joint with a single segment
243
What is the relationship between spinal nerve number, rib number and vertebral number in a thoracic intervertebral foramen?
the spinal nerve number relates to the upper segment number in the vertebral couple
the rib number relates to the lower segment number in the vertebral couple
i.e. T3 nerve exits the intervertebral foramen formed by T3/T4 and rib 4 joints with the vertebral couple
