Welcome message from author
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
CORE CLINICAL CASESSelf-assessment for Medical Students
Anatomy and Physiology
Marjorie E M Allison BSc MD, FRCP
Hon. Senior Research Fellow, Medical Education,
The Medical School, University of Glasgow
Stuart W McDonald BSc MB ChB PhD FRCS
Senior Lecturer in Anatomy, Laboratory of Human Anatomy
University of Glasgow
CONTENTS
1. Cardiology 3 253
Case 1 Congenital heart disease 5 255
Case 2 Down syndrome and congenital cardiac abnormalities 13 265
Case 3 Valvular heart disease and embolism 19 275
Case 4 Myocardial infarction 26 283
Case 5 Heart failure 32 290
Case 6 Venous conditions of the lower limb 39 298
2. Respiratory 45 305
Case 1 Cystic fibrosis 47 307
Case 2 Tuberculosis 53 317
Case 3 Respiratory tract infection 59 324
Case 4 Asthma 65 331
3. Gastroenterology 71 339
Case 1 Epigastric pain 73 341
Case 2 Inflammatory bowel disease 81 350
Case 3 Painless jaundice 87 358
Case 4 Liver disease 93 366
Case 5 Gastro-oesophageal reflux disease 99 375
4. Nephrology 105 383
Case 1 Chronic renal failure 107 385
5. Musculoskeletal 113 395
Case 1 Muscular dystrophy 115 397
Case 2 Wrist fracture 121 404
Case 3 Spine disease 126 409
SELF ASSESSMENT FOR MEDICAL STUDENTS ANATOMY AND PHYSIOLOGY
vi
Case 4 Hernia 132 415
Case 5 Hip fracture 137 422
6. Neurology 143 429
Case 1 Motor neuron disease 145 431
Case 2 Cerebral artery disease 152 440
Case 3 Multiple sclerosis 158 446
Case 4 Spinal cord compression 164 454
Case 5 Stroke 171 462
7. Endocrinology 177 471
Case 1 Addison’s disease 179 473
Case 2 Diabetes mellitus 187 484
Case 3 Thyroid disease 192 492
8. Reproduction 199 499
Case 1 Fertility 201 501
Case 2 Pregnancy 207 508
Case 3 Prostate disease 212 515
9. Haematology 219 523
Case 1 Chronic lymphocytic leukaemia 221 525
Case 2 Iron deficiency anaemia 228 533
Case 3 Lymph nodes and HIV 236 542
10. Dermatology 243 551
Case 1 Psoriasis 245 553
143
NE
UR
OLO
GY
NEUROLOGY CASE 1
NEUROLOGY CASES: QUESTIONS
145
NE
UR
OLO
GY
NEUROLOGY CASE 1
NEUROLOGY
1. MOTOR NEURON DISEASE
You are on duty at a local hospice. 34-year-old Mr Wilson is
admitted for one week of respite care. It is your duty to clerk him
in. Mr Wilson was diagnosed with motor neuron disease 18 months
ago.
1. What is motor neuron disease? ½ mark
2. Which components of the central nervous system (CNS) are affected in
motor neuron disease? 1½ marks
3. In which pathways from the motor cortex do most motor impulses
descend? 1 mark
4. What is a motor unit? 1 mark
Since motor neuron disease affects motor neurons, the clinical
manifestations are primarily within skeletal muscles rather than in
smooth or cardiac muscle.
Q
Q
Q
Q
SELF-ASSESSMENT FOR MEDICAL STUDENTS ANATOMY AND PHYSIOLOGY
NE
UR
OLO
GY
146
5. Complete the following table comparing the three muscle types. 6 marks
Skeletal Cardiac Smooth
Striated or non-striated?
Peripheral or central nucleus/nuclei?
Single or multiple nuclei?
Small, large or very large fibre diameter?
After taking a full and detailed history, you examine Mr Wilson.
During the examination of the nervous system, you find that in Mr
Wilson’s upper limbs there are muscle wasting, fasciculation and
reduced power in all muscle groups.
6. What do the fasciculations indicate? 1 mark
You continue with the neurological examination and find there is
also reduced power in the lower limbs.
7. Identify the following features on the diagram (Figure 6.1) of the calf
muscles of the right lower limb. 3 marks
A –
B –
C –
D –
Q
Q
Q
147
NE
UR
OLO
GY
NEUROLOGY CASE 1
Figure 6.1: Anatomy of the calf muscles of the right lower limb.
After examining Mr Wilson you present your findings to the on-
call consultant. You note that there was no involvement of the
extraocular muscles. The consultant explains to you that in motor
neuron disease the extraocular muscles are often not involved and,
if they are, it is a very late feature of the disease. She also tells you
that in patients with advanced motor neuron disease, movement
of the eyeball is often the only means of communication. Special
boards are used which allow the patient to spell out words by
looking at letters on the board in order to communicate.
A
B
C
D
SELF-ASSESSMENT FOR MEDICAL STUDENTS ANATOMY AND PHYSIOLOGY
NE
UR
OLO
GY
148
8. List the six muscles responsible for moving the eyeball and give the
nerve supply of each. 3 marks
Mr Wilson’s wife explains that a few months ago Mr Wilson lost the
ability to chew and swallow safely. He had lost almost a stone in
weight before a percutaneous endoscopic gastrostomy (PEG) tube
was inserted by the surgical team.
9. What is a PEG tube? 1 mark
10. Identify the muscles that are shown in this illustration
(Figure 6.2). 2 marks
Q
Q
Q
Figure 6.2: Some muscles of chewing and swallowing
A
BD
C
149
NE
UR
OLO
GY
NEUROLOGY CASE 1
½ mark for each of the following:
A –
B –
C –
D –
11. What is the innervation of the ‘muscles of mastication’? 1 mark
During examination of Mr Wilson’s cranial nerves, you find
abnormalities of the facial nerve. You find he can only raise his
eyebrows minimally and not against resistance.
12. Which muscle is responsible for raising the eyebrows? 1 mark
You notice that Mr Wilson is also unable to close his eyes tightly.
13. Which muscle is responsible for this action? 1 mark
On further examination of the facial nerve you notice Mr Wilson has
great difficulty when asked to ‘blow out his cheeks’.
14. Which muscle is being used in this part of the examination? 1 mark
Q
Q
Q
Q
SELF-ASSESSMENT FOR MEDICAL STUDENTS ANATOMY AND PHYSIOLOGY
NE
UR
OLO
GY
150
As well as supplying the muscles of facial expression, the facial
nerve has sensory and autonomic functions.
15. What are the sensory and autonomic functions of the facial
nerve? 2 marks
Nearing completion of your examination of the cranial nerves you
find that Mr Wilson is unable to shrug his shoulders.
16. Which cranial nerves are responsible for this action? 1 mark
17. The following diagram (Figure 6.3) shows the attachments of the cranial
nerves to the brain. Identify structures A–F. 3 marks
Q
Q
Q
Figure 6.3: Attachments of the cranial nerves to the brain
A
B
C
D
E
F
151
NE
UR
OLO
GY
NEUROLOGY CASE 1
½ mark for each of the following:
A –
B –
C –
D –
E –
F –
BIBLIOGRAPHY&
Hiatt J L, Gartner L P. 2000. Textbook of Head and Neck Anatomy, 3rd edn. New
York: Lippincott, Williams and Wilkins.
Johnson D R, Moore W J. 1997. Anatomy for Dental Students, 3rd edn. Oxford:
Oxford University Press.
Kiernan J A. 2005. Barr’s The Human Nervous System: An Anatomical Viewpoint,
8th edn. Philadelphia: Lippincott Williams and Wilkins.
Standring S. 2005. Gray’s Anatomy, 39th edn. Edinburgh: Elsevier Churchill
Livingstone.
Tortora G J, Grabowski S. 2002. Principles of Anatomy and Physiology, 10th edn.
New York: John Wiley.
429
NE
UR
OLO
GY
NEUROLOGY CASE 1
NEUROLOGY CASES: ANSWERS
431
NE
UR
OLO
GY
NEUROLOGY CASE 1
NEUROLOGY
1. MOTOR NEURON DISEASE
You are on duty at a local hospice. 34-year-old Mr Wilson, is
admitted for one week of respite care. It is your duty to clerk him
in. Mr Wilson was diagnosed with motor neuron disease 18 months
ago.
1. What is motor neuron disease? ½ mark
Motor neuron disease is a degenerative neurological disease.
2. Which components of the central nervous system (CNS) are affected in
motor neuron disease? 1½ marks
Neurons in the motor cortex (½ mark), cranial nerve nuclei (½ mark) and anterior
horn cells/corticospinal tracts (½ mark) within the spinal cord.
LEARNING POINT
The cause of motor neuron disease is unknown. Oxidative damage,
abnormal protein aggregation and abnormal axonal transport are all
thought to be involved. The incidence is around 2/100 000 per annum
and it is slightly more common in males. The typical age of onset is 30–40
years. There is no cure for motor neuron disease and the patient’s condition
deteriorates progressively. Survival from diagnosis is rarely more than three
years.
1
3. In which pathways from the motor cortex do most motor impulses
descend? 1 mark
Lateral and anterior corticospinal tracts (½ mark) and the corticonuclear
(corticobulbar) tracts (½ mark).
Q
A
Q
A
Q
A
SELF-ASSESSMENT FOR MEDICAL STUDENTS ANATOMY AND PHYSIOLOGY
NE
UR
OLO
GY
432
LEARNING POINT
A small amount of motor activity may be mediated by the vestibulospinal,
rubrospinal and tectospinal tracts.
1
4. What is a motor unit? 1 mark
A single somatic (lower) motor neuron (½ mark) and all the muscle fibres it
stimulates (½ mark).
Since motor neuron disease affects motor neurons, the clinical
manifestations are primarily within skeletal muscles rather than in
smooth or cardiac muscle.
5. Complete the following table comparing the three muscle types. 6 marks
Skeletal Cardiac Smooth
Striated or non-
striated?
Striated (½ mark) Striated (½ mark) Non-striated (½ mark)
Peripheral or central
nucleus/nuclei?
Peripheral (½ mark) Central (½ mark) Central (½ mark)
Single or multiple
nuclei?
Multiple (½ mark) Single (½ mark) Single (½ mark)
Small, large or very
large fibre diameter?
Very large (½ mark) Large (½ mark) Small (½ mark)
After taking a full and detailed history, you examine Mr Wilson.
During the examination of the nervous system, you find that in Mr
Wilson’s upper limbs there are muscle wasting, fasciculation and
reduced power in all muscle groups.
6. What do the fasciculations indicate? 1 mark
That lower motor neurons have been affected.
Q
A
Q
Q
A
433
NE
UR
OLO
GY
NEUROLOGY CASE 1
LEARNING POINT
Fasciculations are small involuntary contractions of a motor unit. They are a
feature of lower motor neuron disease. They can only be seen if the muscle
is relaxed.
1
You continue with the neurological examination and find there is
also reduced power in the lower limbs.
7. Label the following diagram (Figure 6.1) of the calf muscles of the right
lower limb. 3 marks
Q
Figure 6.1: Anatomy of the calf muscles of the right lower limb.
A
B
C
D
SELF-ASSESSMENT FOR MEDICAL STUDENTS ANATOMY AND PHYSIOLOGY
NE
UR
OLO
GY
434
A – Lateral head of the gastrocnemius (½ mark).
B – Medial head of the gastrocnemius (½ mark).
C – Soleus (1 mark).
D – Calcaneal/Achilles tendon (1 mark).
After examining Mr Wilson you present your findings to the on-
call consultant. You note that there was no involvement of the
extraocular muscles. The consultant explains to you that in motor
neuron disease the extraocular muscles are often not involved and,
if they are, it is a very late feature of the disease. She also tells you
that in patients with advanced motor neuron disease, movement
of the eyeball is often the only means of communication. Special
boards are used which allow the patient to spell out words by
looking at letters on the board in order to communicate.
8. List the six muscles responsible for moving the eyeball and give the
nerve supply of each. 3 marks
Superior rectus Oculomotor nerve/CN III
Inferior rectus Oculomotor nerve/CN III
Medial rectus Oculomotor nerve/CN III
Lateral rectus Abducens nerve/CN VI
Superior oblique Trochlear nerve/CN IV
Inferior oblique Oculomotor nerve/CN III
½ mark for each muscle and its innervation.
LEARNING POINT
The levator palpebrae superioris muscle also lies in the orbit. It moves the
eyelids rather than the eyeball and is supplied by the oculomotor nerve.
1
Q
A
435
NE
UR
OLO
GY
NEUROLOGY CASE 1
Mr Wilson’s wife explains that a few months ago he lost the ability
to chew and swallow safely. He had lost almost a stone in weight
before a percutaneous endoscopic gastrostomy (PEG) tube was
inserted by the surgical team.
9. What is a PEG tube? 1 mark
A PEG tube allows a nutrient solution to be passed directly into the stomach (1
mark) alleviating the need to chew or swallow food.
10. Label the muscles that are shown in this illustration
(Figure 6.2). 2 marks
Q
A
Q
Figure 6.2: Some muscles of chewing and swallowing
½ mark for each of the following:
A – Lateral pterygoid.
B – Medial pterygoid.
C – Buccinator.
D – Superior constrictor.
A
A
BD
C
SELF-ASSESSMENT FOR MEDICAL STUDENTS ANATOMY AND PHYSIOLOGY
NE
UR
OLO
GY
436
11. What is the innervation of the ‘muscles of mastication’? 1 mark
Mandibular nerve/trigeminal nerve/CN V.
During examination of Mr Wilson’s cranial nerves, you find
abnormalities of the facial nerve. You find he can only raise his
eyebrows minimally and not against resistance.
12. Which muscle is responsible for raising the eyebrows? 1 mark
Frontalis/occipto-frontalis muscle.
You notice that Mr Wilson is also unable to close his eyes tightly.
13. Which muscle is responsible for this action? 1 mark
Orbicularis oculi.
On further examination of the facial nerve you notice Mr Wilson has
great difficulty when asked to ‘blow out his cheeks’.
14. Which muscle is being used in this part of the examination? 1 mark
Orbicularis oris.
LEARNING POINT
A common misconception is that asking a patient to ‘blow out his/her
cheeks’ is testing the buccinator muscles. The test actually relies upon
pursing of the lips to create an airtight seal, which involves the orbicularis
oris.
1
Q
A
Q
A
Q
A
Q
A
437
NE
UR
OLO
GY
NEUROLOGY CASE 1
As well as supplying the muscles of facial expression, the facial
nerve has sensory and autonomic functions.
15. What are the sensory and autonomic functions of the facial
nerve? 2 marks
Sensory – taste (½ mark) from the anterior two-thirds of the tongue (½ mark).
Autonomic – the secretion of saliva (½ mark) and tears (½ mark).
LEARNING POINT
Parasympathetic fibres in the facial nerve stimulate the secretion of saliva
from only the submandibular, sublingual and minor glands. The parotid
gland is innervated by parasympathetic fibres in the glossopharyngeal
nerve.
1
Nearing completion of your examination of the cranial nerves you
find that Mr Wilson is unable to shrug his shoulders.
16. Which cranial nerves are responsible for this action? 1 mark
The spinal accessory nerves.
Q
A
A
Q
A
SELF-ASSESSMENT FOR MEDICAL STUDENTS ANATOMY AND PHYSIOLOGY
NE
UR
OLO
GY
438
17. The following diagram (Figure 6.3) shows the attachments of the cranial
nerves to the brain. Identify structures A–F. 3 marks
Q
A
B
C
D
E
F
Figure 6.3: Attachments of the cranial nerves to the brain.
½ mark for each of the following:
A – Olfactory bulb.
B – Optic nerve.
C – Optic tract.
D – Trigeminal nerve.
E – Abducens nerve.
F – Hypoglossal nerve.
A
439
NE
UR
OLO
GY
NEUROLOGY CASE 1
BIBLIOGRAPHY&
Hiatt J L, Gartner L P. 2000. Textbook of Head and Neck Anatomy, 3rd edn. New York:
Lippincott, Williams and Wilkins.
Johnson D R, Moore W J. 1997. Anatomy for Dental Students, 3rd edn. Oxford:
Oxford University Press.
Kiernan J A. 2005. Barr’s The Human Nervous System: An Anatomical Viewpoint, 8th
edn. Philadelphia: Lippincott Williams and Wilkins.
Standring S. 2005. Gray’s Anatomy, 39th edn. Edinburgh: Elsevier Churchill
Livingstone.
Tortora G J, Grabowski S. 2002. Principles of Anatomy and Physiology, 10th edn.
New York: John Wiley.
Related Documents
