Upper Limb Flashcards
Difference between upper and lower motor neuron origin?
Upper = brain or spinal cord Lower = nerve root, peripheral nerve, NMJ or muscle
What are the UMN signs?
No fascicultations or wasting, pronator drift may be present, increase tone (spasticity or rigidity), Pyramidal pattern of weakness e.g. extensors weaker than flexors in arms and opposite in legs) and exaggerated/brisk reflex (hyperreflexia)
WHat are the LMN signs?
Wasting and fascicultations of muscles. May be some drift/movement of the arms if weakened or deafferented but not pronator drift, different patterns of weakness depending on cause e.g. proximal in muscle disease and distal in peripheral neuropathy, reduce or absnt (hyporeflexia or areflexia)
What equipment wil you need?
Tendon hammer, neurotip, cotton wool, tuning fork 128Hx
What clinical signs on general inspection?
Scars, wating of muscles (LMN or disuse atrophy), tremor, fasciculations, pseudoarthetosis, chorea, myoclonus, tardive dyskinesia, hypomimia, ptosis and frontal balding (with myotonic dystrophy) and ophthalmoplegia e.g. MS or myasthenia gravis
How do you assess pronator drift?
Ask patient to hold arms out in front with palms up for 20-30 second and observe for pronation. Then check again with patients eyes closed
What tone features are you looking for?
Spsticity, rigidity, cogwheeling and hypotonia.
Spasticity is associated with pyramidal tract lesions e.g. stroke and rigidity is associated with extrapyramidally e.g. Parkinsons
Spasticity is velocity dependent and rigidity is velocity independent.
Rigidity subtypes: cogwheel and lead pipe.
Cogwheel = tremor superimposed on hypertonia e.g. parkinsons.
Lead pipe = unifrom increased tone e.g. neuroleptic malignant syndrome
Shoulder abduction myotome and muscles?
C5 axillary and deltoid + other shoulder abductors
Shoulder adduction myotome and muscles?
C67 thoracodorsal nerve and teres major, lat dorsi and pec major
Elbow flexion myotome and muscles?
C56 musculocutaneous and radial. Briceps brachii, coracobrachialis and brachialis
Elbow extension myotome and muscles?
C7 radial and triceps brachii
Wrist extension myotome and muscles?
C6 radial and wrist extensors
Wrist flexion myotome and muscles?
C67 median and wrist flexors
Finger extension myotome and muscles?
C7 radial and extensor digitorum
Finger abduction myotome and muscles?
T1 ulnar and first dorsal interosseus and abductor digiti minimi
Thumb abduction myotome and muscles?
T1 median and abductor pollicis brevis
What scale to assess power?
MRC muscle power assessment scale
What reflexes are you testing?
Biceps (C56), supinator/brachioradialis (C56), triceps reflex (C7)
Describe hypo vs hyperreflexia?
Hyper = UMN lesions e.g. stroke or spinal cord lesions. Hypo = LMN e.g. brachial plexus pathology or peripheral nerve injury.
Cerebellar disease reflex?
‘pendular’ which means less brisk and slower in their rise and fall.
What are the areas for the dermatomes?
C5 = lateral aspect of the lower edge of the deltoid muscle (regimental badge) C6 = palmar side of the thumb C7 = palmar side of middle finger C8 = palmar side of little finger T1 = medial aspect of antecubital fossa, proximal to medial epicondyle of the humerus
Describe light touch and pin prick test, and tuning fork.
Light touch does dorsal columns and spinothalamic. Pin prick just spinothalamic and tunic fork just dorsal columns
Describe proprioception test?
Joint position sense via dorsal columns.
Describe sensory loss in mononeuropathies?
Localised sensory disturbance in area supplied by affected nerve
Describe sensory loss in peripheral neuropathy?
Symmetrical sensory deficits in ‘glove and stocking’ distribution in peripheral limbs. Most common causes are DM and alcohol excess
Describe sensory loss in radiclopathy?
Nerve root damage e.g. compression by herniated intervertebral disc, resulting in sensory disturbances in the associated dermatomes
Describe sensory loss in spinal cord damage?
Sensory loss both at and below the level of involvement in a dermatomal pattern due to its impact on the sensory tracts running through the cord
Describe sensory loss in thalamic lesions?
Contralateral sensory loss e.g. stroke
Describe sensory loss in myopathies?
Involve symmetrical proximal muscle weakness
How to assess co-ordination?
Finger to nose test
What does finger to nose test show?
Cerebellar pathology shows both dysmetria and intention tremor.
Dysmetria = lack of coordination of movement
Intention tremor = broad, coarse, low-frequency tremor that occurs as limb reaches end of deliberate movement.
Presence of both shows ipsilateral cerebellar pathlogy
What is inability to do rapid, alternating movements?
Dysdiadochokinesia = feature of ipsilateral cerebellar pathology
What further assessments would you do?
Cranial nerve, lower limbs and cerebellar assessment. Neuroimaging e.g. MRI spine and head
