Neuro Flashcards
What are your differentials for this patient? (Bilateral UMN lesion)
This patient presents with bilateral upper motor symptoms in her lower limbs, and in a young female my impression is that of a demyelinating disease such as multiple sclerosis. However, I would also consider a myelopathy or motor neurone disease in my differential.
How would you further investigate this patient? (?MS)
A patient with suspected Multiple Sclerosis would need to be investigated further, including a full history looking for autonomic symptoms or previous attacks. I would like to refer the patient for specialist Ix such as a lumbar puncture to look for oligoclonal bands, MRI and visual evoked potentials.
The management for this patient will involve members of the multidisciplinary team including PT’s, OT’s and social workers.
Medical treatment options include disease modifying drugs such as IFN-B or biologics such as Natalizumab. During acute attacks, steroids such as methyl prednisolone can be used to reduce the duration and severity of an attack. Other pharmacological options are used for control of symptoms such as pain (gabapentin), spasticity (baclofen) or urinary dysfunction (oxybutynin).
Please present your examination (normal lower limbs)
I performed a lower limbs neurological examination on this gentleman, who appeared comfortable at rest, with no equipment around the bed.
Examination of the legs showed no stigmata of neurological disease. Tone was normal and there was no clonus. Power was 5/5 in all muscle groups tested. Co-ordination was intact and reflexes were present.
Sensation was intact in all dermatomes for light touch, (pin prick), vibration and proprioception.
The gait was normal.
In summary, these findings are consistent with a normal lower limb neurological examination.
To complete my examination I would examine the cranial nerves and upper limbs and view any previous neuroimaging.
Please present your examination (peripheral neuropathy)
I performed a lower limbs neurological examination on this gentleman, who appeared comfortable at rest, with no equipment around the bed.
Examination of the legs showed no stigmata of neurological disease. Tone was normal and there was no clonus. Power was 4/5 for ankle dorsi and plantar flexion, and 5/5 in all other proximal muscle groups. Co-ordination was intact and reflexes were present.
Proprioception, light touch and vibration sense were reduced bilaterally in a stocking distribution to the level of the mid-foot/ankle/mid-calf. Sensation was otherwise intact.
The gait was normal.
In summary, these findings are consistent with a peripheral neuropathy.
To complete my examination I would examine the cranial nerves and upper limbs and view any previous neuroimaging.
What are your differentials for peripheral neuropathy?
There are many causes of peripheral neuropathy including metabolic, inflammatory, infection and drugs.
Metabolic causes include diabetes, B12 deficiency and alcohol
Inflammatory causes include vasculitis and amyloidosis
Infective causes include HIV and lyme disease
Drug causes include isoniazid and chemotherapies
What are your differentials for proximal weakness?
Proximal weakness is commonly neurological or myopathy related.
Neurological causes include myasthenia gravis or lambert eaton syndrome.
Myopathic causes can be classed into metabolic, inflammatory, infection and muscular dystrophy
Metabolic causes include Cushing’s and thyroid disease
Inflammatory causes include polymyositis and dermatomyositis and vasculitis
Infective causes include HIV and syphilis.
What are your differentials for unilateral UMN lesion?
Lesion is in the brain or the spinal cord
Causes could be vascular, infective, inflammatory or malignant
Common brain causes - Stroke, MS, SOL (primary or secondary brain tumour, TB abscess)
Common spinal cord causes- Trauma, SOL (mets, primary tumour, abscess), MS
What are your differentials for unilateral LMN lesion?
Lesion is in the nerve roots, plexus, peripheral nerve or neuromuscular junction.
Nerve root radiculopathy- disc herniation, cervical spondolysis, spinal stenosis, polio
Plexus lesion could be due to trauma or congenital- Erb’s and Klumpky’s.
Peripheral nerve lesions could be due to trauma or compression of the nerve, diabetes
NMJ- Myasthenia gravis
Please present this patient (Parkinsonism)
Today I performed a neurological examination on a 75-year-old gentleman to assess for clinical features of Parkinson’s disease. On general inspection, the patient demonstrated hypomimia, reduced spontaneous movements in his arms and a soft voice. An asymmetrical tremor was noted in his left hand at rest, involving his forefinger and thumb. A re-emergent postural tremor in his left hand was elicited upon extension of both arms. Asymmetric bradykinesia was detected on the left side with progressive slowness and amplitude of alternating movements. Assessment of tone revealed rigidity in the left wrist, elbow and ankle. Observation of the patient’s gait demonstrated a stooped posture with a reduced arm swing. He had a short stride length and was hesitant when turning. These findings are consistent with the clinical features of parkinsonism.”
How do people with Parkinsonism present?
Classic triad - tremor, bradykinesia, rigidity
Anosmia, sleep disturbance, micrographia
Shuffling gait and stooped posture, reduced arm swing
Hypomimic face
Depression, dementia, hallucinations
Causes include idiopathic PD (loss of dopaminergic neurons in the substantia nigra), PSPs, drugs, infarcts and Wilson’s disease.
Rx of idiopathic PD MDT - conservative, medical and surgical OT/PT input ADL + mobility, psychiatry - L-DOPA with carbidopa (efficacy dec over time, on-off, nausea, dyskinesias, compulsive behaviour), ropinirole, \+ bromocriptine, MAO-B inhib, amantadine
Deep brain stimulations
What would be the red flag conditions for bilateral weakness?
Cauda equina compression - alternating or bilateral root pain in legs, saddle anaesthesia, loss of anal tone on pr, bladder ± bowel incontinence.
Cord compression Bilateral pain, lmn signs at level of compression, umn and sensory loss below, sphincter disturbance.
URGENT spinal MRI
Rx - neurosurgical referral -
prevents irreversible loss, eg laminectomy for disc protrusions, radiotherapy for tumours, decompression for abscesses.
Causes
(same for both): bony metastasis (look for missing pedicle on x-ray), large disc protrusion, myeloma, cord or paraspinal tumour, tb, abscess.
Nerve root testing - myotomes
UPPER LIMB C5 - shoulder abduction - elbow flexion C7 - elbow extension, wrist flexion C6 - wrist extension C8 - thumb extension, finger flexion T1 - finger abduction
LOWER LIMB L2 - hip flexion L3 - knee extension L4 - ankle dorsiflexion L5 - big toe extension S1 - ankle plantarflexion
Peripheral nerve mononeuropathy
UPPER LIMB
Median T1
= Wasting of abductor pollicis brevis (thumb abduction); sensory loss on thenar eminence
Ulnar T1
= interossei (index abduction); sensory change in ulnar distribution
Radial C7
= finger and wrist drop; sensory change in radial distribution
LOWER LIMB Common peroneal = foot drop Lateral cutaneous nerve (meralgia paraesthetica) Sciatic nerve Femoral nerve = weakness and wasting of the quadriceps = sensory loss on the inner aspect of the thigh
What are your differentials for a bilateral LMN lesion
Sensory only- same as peripheral neuropathy causes
Motor only- GBS, lead poisoning , CIDP (chronic inflammatory demyelinating polyneuropathy)
