The image above illustrates an NADH-TR stain showing dark type 1 and pale type 2 fibers.

1
The image above illustrates an NADH-TR stain
showing dark type 1 and pale type 2 fibers. The
latter would appear dark in ATPase stain. At
least two subtypes are now identified among
type 2 fibers using different methods of
staining. All of the muscle fibers in a given
motor unit are of the same histochemical types,
either type 1 or type 2, suggesting that the
neuron determines the type of muscle fibers. The
fibers of adjacent motor units overlap and
intermingle resulting in a characteristic mosaic
or checkerboard pattern.
2
This HE image shows a large group of atrophic
fibers center next to a group of normal fibers
(left), a typical example of group atrophy.
3
The denervated muscle fibers are in the vicinity
of intact axons and may become reinnervated by
collateral sprouting. Since the motor neuron
determines the muscle fiber type, all of the
re-innervated fibers are converted to a single
histochemical fiber type with loss of the normal
checkerboard pattern. This phenomenon is called
"type grouping." The image above illustrates
typical type grouping in an ATPase stain. Note
the area of dark type 2 fibers next to a large
area of pale type 1 fibers. Normal checkerboard
pattern is lost.   
4
The frontal chest radiograph showed a large
antrerior mediastinal soft tissue mass on the
right side adjacent to the heart. A plain and
contrast enhanced CT Chest showed a large, well
defined, lobulated, anterior and superior
mediastinal mass with cystic components. In view
of the clinical presentation this lesion was
thought to be thymoma.
5
Amytrophic lateral sclerosis weakness, atrophy,
fasciculations hyperreflexia
6
Note atrophy in ALS
7
Lou Gehrigfamous N.Y. Yankee first baseman who
had ALS and thus it is commonly called Lou
Gehrig disease.
8
note thin ventral roots in ALS patient-why?
9
Lumbosacral radiculopathy. Sagittal MRI showing
loss of intervertebral disc height at L5/S1.
Herniations of the nucleus pulposus are noted at
L4/5 and L5/S1 Think about patients problems,
physical exam and tests you would request to
verify your diagnosis!
10
Chief complaintRight leg pain History of
present illness42 year old female with an eight
week history of mostly right leg pain. The pain
radiates to the sole and outside of her foot
and is accompanied by numbness and tingling.
This episode of pain started as back pain but
within a week had moved to being mostly in her
leg. Physical exam 42 year old healthy female
who stands through most of the history. She
has an absent ankle jerk on the right leg. There
are no focal motor deficits, and the
neurological exam is otherwise negative. She has
a markedly positive straight leg test and
crossed straight leg test (raising the affected
and unaffected leg recreates her leg pain).
Imaging studiesMRI scan shows a large disc
herniation at L5-S1. There is also disc
degeneration present at the L5-S1 disc. The axial
scan (not shown) shows that the disc impinges on
the right S1 nerve root.
11
This is an image of an MRI of the normal lumbar
spine low back. The vertebrae are marked with
numbers one can see lumbar vertebrae 2 through
5 and finally the S1 vertebra which is the
Sacral 1 vertebrae. The discs are in-between
the vertebrae and are number accordingly. For
example, the L3/4 disc has a black arrow
pointing to it. The discs always have 2 numbers
for identification. The Red arrow points to
the fluid in spinal canal this fluid appears as
a whitish color on the MRI. The Blue arrow points
to a nerve roots in the canal.
12
MRI delineates a mass of the distal 6
centimeters of the spinal cord involving the
conus medullaris, (which ends at the upper
aspect of L2). Think about this patients
neurological deficits/problems!
13
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14
A 34-year-old man suffered from severe neck and
shoulder radicular pain of 1 year duration. His
pain soon became electric-like, shooting in
nature and involving the left upper limb and
ulnar side of the left hand. Neurologically, he
had minimal sensory impairment over the left C7
dermatome. An MRI of the cervical spine
demonstrated a C6-C7 herniated nucleus pulposus
((at right) A needle electromyogram examination
confirmed the presence of a C6-C7
radiculopathy.
15
bony metastasis affecting cauda equina see the
conus just dorsal to it? possible deficits in
comparison to conus lesions?
16
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17

• in A, patient is attempting to raise eyelids as
  high as possible
• In B, same patient has had an iv injection of
  Tensilon, an acetylcholinsterase inhibitor.
  Eyelids go higher for a while

Representative of Case History 2 MYASTHENIA
GRAVIS
B
A
18
Cervical or lumbar? Arrow points to ?????
19
Think of the neurological deficits/pathways/tests
associated with SCD! Write a practice question
For me! Please make E the answer so I can
answer it correctly!
Vitamin B-12associated neurological diseases.
Pernicious anemia. Characteristic lemon-yellow
pallor with raw beef tongue lacking filiform
papillae
20
What do these MRIs show?
21
What is the arrow pointing to?
22
Dorsal view of spinal cord, dorsal roots and
ganglia of C7
23
Think about the the results of a lesion here.
Write a few practice questions!
24
What pathway is in blue? Right or left?
25
Bulge/nucleus indicated by the arrowClarks
nucleus Think of a question I could ask!
26
Any thoughts on the Babinski?
27
WHERE IS THE EXACT LOCATION OF THE LESION? JUST
WHAT IS CAUSING THE DEFICIT?
28
The thin bridge of bone that connects the
superior and inferior facets is the pars
interarticularis if broken spondylolysis.
Spondylolisthesisslipping forward of the
vertebral body ("listhesis" means "to slip
forward"). Most common at L4 and L5 where spine
curves into its most pronounced "S" shape and
where the stress is heaviest.
29
LEFT The picture above shows Spondylolysis. Notic
e the scottie dog shape of the pars
interarticularis and the fracture line where the
dog's collar would be. RIGHT    This picture
shows a more severe state, Spondylolisthesis. 
This condition occurs when the fracture on the
right becomes unstable and allows the vertebrae
above to slip anteriorly (to the front) on the
vertebrae below.  
30
SCOTTIE
31
Where is the lesion that results in this
mannerism? Perhaps he has a C6 (six shooter)
radiculopathy with funny feelings (paresthesias)!
32
F
D
C
B
E
Know These!!!!
A
33
LMN?? or Corticobulbar?
34
F
E
D
B
C
Know These!!!!
A
35
C
D
G
E
B
A
F
Know These!!!!
36
(No Transcript)
37
K N O W
E
C
B
D
A
38
K N O W P Y R
PYR DEC
OLIVE
PYR
39
KNOW PYRAMID
40
5m
5s
7m
PONS
7i
8a
8v
9
6
10
OLIVE
12
PYRAMID
11