(CPA) upper limb exam Flashcards
what four components are assessed in an upper limb neurological exam?
tone
power
reflexes
sensation
in the upper limb exam, in which muscle groups is tone assessed?
shoulder, elbow, and wrist
describe how to assess tone in the upper limb
support the patient’s arm by holding their hand and elbow
ask the patient to relax fully ‘go floppy’ and allow you to fully control the movement of their arm
1) circumduct the shoulder
2) flex/extend the elbow
3) circumduct (pronate + supinate + flex + extend) the wrist
feel for abnormal tone as you assess each joint (spasticity, rigidity, cogwheeling hypotonia)
how is tone assessed at the shoulder?
circumduction
how is tone assessed at the elbow?
flexion & extension
how is tone assessed at the wrist?
flexion & extension
pronation & supination
what do you feel for when assessing tone in the upper limb?
spasticity, rigidity, cogwheeling hypotonia
what causes spasticity and when is it detected?
spasticity is detected when assessing tone
= caused by pyramidal tract lesions
what causes rigidity and when is it detected?
rigidity is detected when assessing tone
= caused by extrapyramidal tract lesions (e.g. Parkinson’s)
what causes hypotonia and when is it detected?
hypotonia is detected when assessing tone
= caused by LMN (lower motor neurone) lesion
what causes hypertonia and when is it detected?
hypertonia is detected when assessing tone
= caused by UMN (upper motor neurone) lesion
explain how hypertonia is caused
upper motor lesion = HYPERtonia
the UMNs exhibit an inhibitory effect on the LMNs and so if there is a UMN lesion and this inhibition is lost, the LMNs are overactive
= exaggerated muscle tone
explain how hypotonia is caused
lower motor lesion = HYPOtonia
loss of the LMNs impairs the ability to stimulate the extrafusal muscle fibres
= decreased muscle tone
for the ‘power’ component of the upper limbs exam, which joints are assessed?
shoulder joint
elbow joint
wrist joint
(maybe joints of the heads = ICPs, MCPs)
how is the shoulder joint assessed for power?
1) assess abduction = ask the patient to lift their arm outwards while you provide resistance by pushing downwards
2) assess adduction = ask the patient to push their lifted arm inwards while you provide resistance by pushing outwards
how is the elbow joint assessed for power?
1) assess flexion = ask patient to flex their elbow while you resist the motion
2) assess extension = ask patient to extend their elbow while you resist the motion
3) assess abduction = ask patient to abduct their elbow while you resist the motion
4) assess adduction = ask patient to adduct their elbow while you resist the motion
how is the wrist joint assessed for power?
1) assess flexion = ask patient to flex their wrist while you resist the motion
2) assess extension = ask patient to extend their wrist while you resist the motion
3) assess abduction = ask patient to abduct their wrist while you resist the motion
4) assess adduction = ask patient to adduct their wrist while you resist the motion
5) assess supination = ask patient to supinate their wrist while you resist the motion
6) assess pronation = ask patient to pronate their wrist while you resist the motion
which myotome does shoulder abduction rely on?
C5
which myotome does shoulder adduction rely on?
C6/C7
which muscles are responsible for shoulder adduction?
teres major
latissimus dorsi
pectoralis major
which muscles are responsible for shoulder abduction?
deltoid
which myotome does elbow flexion rely on?
C5/C6
which myotome does elbow extension rely on?
C7
which muscles are responsible for elbow flexion?
biceps brachii
which muscles are responsible for elbow extension?
triceps brachii
which myotome does wrist flexion rely on?
C6/C7
which muscles are responsible for wrist flexion?
flexors of the wrist
how is muscle power scored?
using a 0-5 MRC Power Scale
what does a 0 on the MRC power scale mean?
no movement
what does a 1 on the MRC power scale mean?
barest flicker of movement of the muscle, though not enough to move the structure to which it’s attached
what does a 2 on the MRC power scale mean?
voluntary movement which is not sufficient to overcome the force of gravity
what does a 3 on the MRC power scale mean?
voluntary movement capable of overcoming gravity, but not applied resistance
what does a 4 on the MRC power scale mean?
voluntary movement capable of overcoming resistance
what does a 5 on the MRC power scale mean?
normal strength
summarise how power is assessed in an upper limbs exam
resist the movement by applying an opposing force and estimating the power of the contracting muscles
= must isolate the joint first
in the upper limb exam, which reflexes are elicited?
biceps
triceps
supinator
which spinal nerve root is the biceps reflex linked to?
C5, C6
which spinal nerve root is the triceps reflex linked to?
C7, C8
which spinal nerve root is the supinator reflex linked to?
C6
describe how the biceps reflex is elicited
ask patient to relax their arms completely
locate biceps tendon and place a finger of your non-dominant hand on the area
tap finger with tendon hammer to elicit reflex
(repeat on both arms)
describe how the triceps reflex is elicited
ask patient to relax their arms completely
locate triceps tendon (superior to olecranon process of ulna) and place a finger of your non-dominant hand on the area
tap finger with tendon hammer to elicit reflex
(repeat on both arms)
describe how the supinator reflex is elicited
ask patient to relax their arms completely
locate brachioradialis tendon and place a finger of your non-dominant hand on the area
tap finger with tendon hammer to elicit reflex
(repeat on both arms)
what does areflexia suggest?
absence of a reflex = LMN lesion
what does hyperreflexia suggest?
overactive reflex = UMN lesion
what can you do if a reflex is difficult to elicit?
apply reinforcement
= ask the patient either clench the teeth or squeeze an object in the contralateral (other) hand while you directly test the reflex on the limb to be tested
what do abnormally exaggerated myotatic reflexes suggest?
an UMN lesion
what causes areflexia?
complete absence of the reflex caused by
disorder in any of the components of the reflex arc (muscle spindles, afferent sensory neurones, efferent motor neurones and the effector organs - the muscle itself)
what is the grading system used to rate reflexes?
0 = absent
1+ = decreased, but still present (hypo-reflexic)
2+ = normal
3+ = hyper-reflexic
4+ = clonus (repetitive shortening of the muscle after a single stimulation)
how is sensation assessed in an upper limbs exam?
ensure that the patients’ eyes are closed for this assessment (!!)
1) demonstrate normal sensation on the patient’s sternum
2) assess sensation across each of the upper limb dermatomes, comparing left to right at equivalent regions
which dermatomes make up the upper limb?
C5 C6 C7 C8 T1 T2
where is C5 assessed for sensation in the upper limb exam?
‘regimental badge’ area
where is C6 assessed for sensation in the upper limb exam?
palmar thumb
where is C7 assessed for sensation in the upper limb exam?
palmar middle finger
where is C8 assessed for sensation in the upper limb exam?
palmar little finger
where is T1 assessed for sensation in the upper limb exam?
antecubital fossa near medial epicondyle
where is T2 assessed for sensation in the upper limb exam?
axilla
