EMQ: 7
Lower limb weakness
a)
Hereditary motor sensory neuropathy
b)
Multiple sclerosis
c)
Cauda equina lesion
d)
Parasagittal meningioma
e)
Syringomyelia
f)
Guillain-Barre syndrome
g)
Spinal cord compression
h)
Subacute combined degeneration of the cord
i)
Motor neurone disease
j)
Tabes dorsalis
1) A 26-year-old female with spastic paraparesis and
optic neuritis
Answer: b) multiple sclerosis
In a young patient with a neurological deficit one should
consider multiple sclerosis. The patient has evidence of scattered lesions
anatomically and hence the most likely conditions is multiple sclerosis
2) A 65-year-old female with lower limb weakness, with
absent ankle jerks and upgoing plantar response. There is loss of joint
position sense and vibration sense in both feet.
Answer: h) Subacute combined degeneration of the cord
This patient has evidence of motor weakness together with
posterior column involvement. This should make you think of subacute combined
degeneration of the cord. There are few conditions that cause upgoing
plantars with absent ankle jerks (ACES for PACES
page 517). This is further evidence in favour of subacute combined
degeneration of the cord.
3) A 75-year-old male with prostate cancer presents with
backache and evidence of a spastic paraparesis and incontinence of urine and
faeces
Answer: g) spinal cord compression
In a patient with prostate cancer and backache one should
consider metastatic disease. This combined with evidence of spinal cord
involvement in the form of a spastic paraparesis and incontinence should make
you think of spinal cord compression.
4) A 28-year-old female presents with rapidly progressive
weakness in her lower limbs. There is a history of a diarrhoeal illness
preceding the onset of the problem. On examination she has a flaccid weakness
and tendon reflexes are absent.
Answer: f) Guillain-Barre syndrome
The history of a preceding diarrhoeal illness should
alert you to the possibility of an acute inflammatory condition. This coupled
with the flaccid weakness and absent reflexes should suggest to you that the
most likely diagnosis is Guillain-Barre syndrome (acute inflammatory
demyelinating polyradiculoneuropathy)
5) A 50-year-old man with spastic paraparesis,
exaggerated reflexes and upgoing plantars. The upper limb muscles are wasted
and show fasiculations. No sensory involvement.
Answer: I) motor neurone disease
Spastic paraparesis, exaggerated reflexes and upgoing
plantars suggest upper motor neurone involvement. Wasting and fasiculations
show involvement of the lower motor neurone in particular the anterior horn
cell. This combination of features suggests motor neurone disease. The absence
of sensory signs is further evidence in favour of this.
Revision Tip
Revise the causes of paraparesis
(ACES for PACES page 452). Revise this in
conjunction with lesions of the CNS (ACES for
PACES pages 428-438)
Neurology is a difficult area. Read
chapter 16 of ACES for PACES several times and see as many
patients as you can#
