Upper Limb Neuro Exam Flashcards
Is there fasciculations or wasting in a UMN lesion?
No, but there may be some disuse atrophy
Is there fasciculations or wasting in a LMN lesion?
Yes
Is there a pronator drift present in a UMN lesion?
May be present
Is there a pronator drift present in a LMN lesion?
There may be some drift, but not pronator drift
What is tone like in a UMN lesion?
Increased (spasticity or rigidity)
What is tone like in a LMN lesion?
Decreased (hypotonia) or normal
What is power like in a UMN lesion?
- Classically ‘pyramidal’
- Extensors weaker than flexors in arms and vice versa
What is power like in a LMN lesion?
- Different patterns of weakness depending on the cause
What are reflexes like in a UMN lesion?
Exaggerated or brisk (hyperreflexia)
What are reflexes like in a LMN lesion?
Reduced or absent (hyporeflexia or areflexia)
What is a areflexia?
When the muscles don’t respond to stimuli
What is the relevance of looking for scars in an upper limb neuro exam?
May give clues regarding previous spinal, axillary or upper limb surgery
What is the relevance of looking for wasting of muscles in an upper limb neuro exam?
Suggests LMN lesion or disuse atrophy
What is the relevance of looking for tremor in an upper limb neuro exam?
May show resting or intention tremor
What are fasciciulations?
Small, local involuntary muscle contractions and relaxation which may be visible under the skin
What are fasciculations associated with?
LMN pathology e.g. amyotrophic lateral sclerosis
What is pseudoathetosis?
Abnormal writhing movements caused by a failure of proprioception
What is chorea?
Brief, semi-directed, irregular movements that are not repetitive or rhythmic but appear to flow from one muscle to the next
In which condition does chorea typically present?
Huntington’s disease
What is myoclonus?
Brief, involuntary, irregular twitching of a muscle or group of muscles
In what conditions may myoclonus be seen?
- May be benign
- May be seen in several forms of epilepsy
What is tardive dyskinesia?
Involuntary, repetitive body movements which can include protrusion of the tongue, lip-smacking and grimacing
When may tardive dyskinesia show?
Secondary to treatment with neuroleptic medications including antipsychotics and antiemetics
What is hypomimia?
A reduced degree of facial expression
In which condition does hypomimia present?
Parkinson’s disease
In which condition does ptosis and frontal balding occur?
Myotonic dystrophy
What is ophthalmoplegia?
Weakness or paralysis of one or more extra ocular muscles responsible for eye movements
What conditions may present with ophthalmoplegia?
MS or myasthenia gravis
How do you assess for pronator drift?
- Ask the patient to hold their arms out in front of them with their palms facing upwards
- If none occurs, ask the patient to close their eyes and continue
What is the interpretation of a pronator drift?
- If it pronates, they have a pronator drift on that side
- Indicates a contralateral pyramidal tract lesion
Why does pronator drift occur?
In the context of a UMN lesion, the supinator muscles are typically weaker than the pronator muscles
Which muscles groups should you assess for tone?
Shoulder, elbow and wrist of each arm
How do you assess for tone?
- Support the patient’s arm by holding their hand and elbow
- Ask the patient to relax and allow you to fully control the movement of their arm
- Move the muscle groups of the shoulder, elbow and wrist through full range of movements
- Feel for abnormalities of tone
What should be done to assess the tone of the shoulder?
Circumduction (round rotation)
What should be done to assess the tone of the elbow?
Flexion and extension
What should be done to assess the tone of the wrist?
Circumduction (round rotation)
What is spasticity associated with?
Pyramidal tract lesions (e.g. stroke)
What is rigidity associated with?
Extrapyramidal tract lesions (e.g. Parkinson’s)
How is spasticity velocity dependent?
- The faster you move the limb, the worse it is
- Typically increased tone in the initial movement, then suddenly reduces past a certain point
What is associated with spasticity?
Weakness
How is rigidity velocity independent?
It feels the same if you move the limb rapidly or slowly
What are the two main types of rigidity?
Cogwheel & lead pipe
How is cogwheel rigidity described?
A tremor superimposed on the hypertonia, resulting in intermittent increases in tone during movement of the limb
What disease is cogwheel rigidity associated with?
Parkinson’s disease
How is lead pipe rigidity described?
Uniformly increased tone throughout the movement of the muscle
What disease is lead pipe rigidity associated with?
Neuroleptic malignant syndrome
When testing shoulder abduction, what myotome is assessed?
C5 (axillary nerve)
What muscles are tested when doing shoulder abduction?
- Deltoid (primary)
- Other shoulder abductors
How do you test the power of shoulder abduction?
- ‘Bend your elbows and bring your arms out to the sides like a chicken’
- ‘Don’t let me push your shoulder down’
When testing shoulder adduction, what myotome is assessed?
C6/7 (thoracodorsal nerve)
What muscles are tested when doing shoulder adduction?
- Teres major
- Latissimus dorsi
- Pectoralis major
How do you test the power of shoulder adduction?
- ‘Ask the patient to bring their elbows to a 45 degree angle’
- ‘Don’t let me pull your arms away from your sides’
When testing elbow flexion, what myotome is assessed?
C5/6 (musculocutaenous and radial nerve)
What muscles are tested when doing elbow flexion?
- Biceps brachii
- Coracobrachialis
- Brachialis
How do you test the power of elbow flexion?
- ‘Put your hands up like a boxer’
- ‘Don’t let me pull your arm away from you’
When testing elbow extension, what myotome is assessed?
C7 (radial nerve)
What muscles are tested when doing elbow extension?
Triceps brachii
How do you test the power of elbow extension?
- ‘Put your hands up like a boxer’
- ‘Don’t let me push your arm towards you’
When testing wrist extension, what myotome is assessed?
C6 (radial nerve)
What muscles are tested when doing wrist extension?
Extensors of the wrist
How do you test the power of wrist extension?
- ‘Hold your arms out in front of you, with your palms facing the ground’
- ‘Make a fist, cock your wrists back and don’t let me pull them downwards’
When testing wrist flexion, what myotome is assessed?
C6/7 (median nerve)
What muscles are tested when doing wrist flexion?
Flexors of the wrist
How do you test the power of wrist flexion?
- ‘Hold your arms out in front of you, with your palms facing the ground’
- ‘Point your wrists downwards and don’t let me pull them up’
When testing finger extension, what myotome is assessed?
C7 (radial nerve)
What muscles are tested when doing finger extension?
Extensor digitorum
How do you test the power of finger extension?
‘Hold your fingers out straight and don’t let me push them down’
When testing finger abduction, what myotome is assessed?
T1 (ulnar nerve)
What muscles are tested when doing finger abduction?
- First dorsal interosseous (FDI)
- Abductor digiti minimi (ADM)
How do you test the power of finger abduction?
‘Splay your fingers outwards and don’t let me push them together’
When testing thumb abduction, what myotome is assessed?
T1 (median nerve)
When testing thumb abduction, what myotome is assessed?
Abductor pollicis brevis
How do you test the power of thumb abdcution?
‘Point your thumbs to the ceiling and don’t let me push them down’
What is 0 on the MRC muscle power assessment scale?
No contraction
What is 1 on the MRC muscle power assessment scale?
Flicker or trace of contraction
What is 2 on the MRC muscle power assessment scale?
Active movement, with gravity eliminated
What is 3 on the MRC muscle power assessment scale?
Active movement against gravity
What is 4 on the MRC muscle power assessment scale?
Active movement against gravity and resistance
What is 5 on the MRC muscle power assessment scale?
Normal power
What should be done if there is an absent reflex?
- Do a reinforcement manoeurve
- Ask the patient to clench their teeth while you perform
What myotome does the biceps reflex test?
C5/6
How do you perform the biceps reflex?
- Place your non-dominant thumb on the biceps brachia tendon
- Tap your thumb
- Observe for a contraction of the biceps muscle and associated flexion of the elbow
What myotome does the supinator reflex test?
C5/6
How do you perform the supinator reflex?
- Place two fingers on the brachioradialis tendon
- Tap your fingers
- Observe for contraction of the brachioradialis muscle and associated flexion, pronation or supination of the forearm at the elbow
What myotome does the triceps reflex test?
C7
How do you perform the triceps reflex?
- Tap the triceps tendon (medial part of elbow crease)
- Tap the tendon
- Observe for a contraction of the triceps muscle
What is hyperreflexia associated with?
Upper motor neuron lesions e.g. stroke, spinal cord injury
What is hyporeflexia associated with?
Lower motor neuron lesions e.g. brachial plexus pathology or peripheral nerve injury
What is a pendular reflex and what is it seen in?
- Less brisk and slower in rise and fall
- Seen in cerebellar disease
Where can the dermatome for C5 be assessed?
The lateral aspect of the lower edge of the deltoid muscle
Where can the dermatome for C6 be assessed?
The palmar side of the thumb
Where can the dermatome for C7 be assessed?
The palmar side of the middle finger
Where can the dermatome for C8 be assessed?
The palmar side of the little finger
Where can the dermatome for T1 be assessed/
The medial aspect antecubital fossa, proximal to the medial epicondyle of the humerus
How do you assess sensation using light touch sensation?
- Trace some cotton wool on the sternum
- Ask the patient to say ‘yes’ when they feel the sensation
- Assess across the dermatomes
What does light touch sensation assess?
- Dorsal columns
- Spinothalamic Tracys
What does vibration sensation assess?
Dorsal columns
How do you assess sensation using vibration?
- Assess the tuning fork on the patients sternum with eyes closed
- Use the tuning fork on the interphalangeal joint of the patient’s thumb & repeat on the other side
- If impaired: thumb - elbow joint - shoulder joint
What does proprioception sensation assess?
Dorsal columns
How do you assess sensation using proprioception
- Demonstrate ‘up’ and ‘ down’ to patient on thumb before starting
- With eyes closed, ask them to state the movement 3-4 times
- If not accurate: thumb - elbow joint - shoulder
- Repeat on both sides
Why is the finger-to-nose test used in this exam?
To assess upper limb co-ordination
How do you perform the finger-to-nose test?
- Place finger so patient has to fully outstretch their arm
- Ask the patient to touch they nose, then touch your fingertip
- Continue as fast as possible
What may be displayed in the finger-to-nose test and what does this indicate?
- Dysmetria and intention tremor
- Ipsilateral cerebellar tremor
What is dysmetria?
Lack of coordination of movement
What is intention tremor?
A broad, coarse, low-frequency tremor that develops as a limb reaches the endpoint of a deliberate movement
What is dysdiadochokinesia and what may it indicate?
- Inability to perform rapid, alternating movements
- Ipsilateral cerebellar tremor
How do you test for dysdiadochokinesia and what may it indicate?
- Hand turning alternating test
- May indicate cerebral ataxia = movements appearing slow and irregular
What further assessments and investigations may be carried out?
- Full neurological examination (cranial nerves, lower limbs and cerebellar assessments)
- Neuroimaging e.g. MRI spine and head
