Fig. 7.16 Basal ganglia. A Anatomical location. B Coronal view.
Gait disturbance Description Causes
Gait apraxia Small, shuffling steps
Spastic Stiff ‘walking-throughmud’ or scissors gait
Foot drop Foot slapping Neuropathies
Central ataxia Wide-based, ‘drunken’
Functional Variable, often bizarre,
such as professional sports players, may have physiological
muscle hypertrophy. Pseudohypertrophy may occur in muscular
dystrophy but the muscles are weak.
Fasciculations are visible irregular twitches of resting muscles
caused by individual motor units firing spontaneously. This occurs
in lower motor neurone disease, usually in wasted muscles.
Fasciculation is seen, not felt, and you may need to observe
carefully for several minutes to be sure that it is not present.
Physiological (benign) fasciculation is common, especially in the
calves, but is not associated with weakness or wasting. Myokymia
– fine, involuntary fascicular contractions – involves rapid bursts
of repetitive motor unit activity that often affects orbicularis oculi
or the first dorsal interosseus, and is rarely pathological.
These are sudden, shock-like contractions of one or more muscles
that may be focal or diffuse and occur singly or repetitively.
Healthy people commonly experience these when falling asleep
(hypnic jerks). They may also occur pathologically in association
with epilepsy, diffuse brain damage and some neurodegenerative
disorders such as prion diseases. Negative myoclonus (asterixis)
is seen most commonly in liver disease (liver flap).
gait with bilateral Trendelenburg signs (see p. 259 and Fig. 13.37).
Bizarre gaits, such as when patients drag a leg behind them,
are often functional but some diseases, including Huntington’s
disease, produce unusual and chaotic gaits.
Inspection and palpation of the muscles
• Completely expose the patient while maintaining their
• Look for asymmetry, inspecting both proximally and
distally. Note deformities, such as flexion deformities or
• Inspect for wasting or hypertrophy, fasciculation and
Lower motor neurone lesions may cause muscle wasting. This
is not seen in acute upper motor neurone lesions, although
disuse atrophy may develop with longstanding lesions. A motor
neurone lesion in childhood may impair growth (causing a smaller
limb or hemiatrophy) or lead to limb deformity, such as pes
cavus. Muscle disorders usually result in proximal wasting (the
notable exception is myotonic dystrophy, in which it is distal,
often with temporalis wasting). People in certain occupations,
Foot is dragged or lifted high
C Sensory or cerebellar ataxia
based. Feet are thrown forward
In sensory ataxia, patients watch
steadily (positive Romberg sign)
In cerebellar ataxia, turns are
stand steadily with feet together
and patient is slow in getting
Caused by lesions in the basal
Fig. 7.17 Abnormalities of gait.
• Passively move each joint to be tested through as full
a range as possible, both slowly and quickly in all
anatomically possible directions. Be unpredictable with
these movements, in both direction and speed, to prevent
the patient actively moving with you; you want to assess
passive tone. It may be helpful to distract the patient
by asking them to count backwards from 20 while
• Hold the patient’s hand as if shaking hands, using your
other hand to support their elbow. Assess tone at the
wrist and elbow with supination/pronation and flexion/
• Activation (or synkinesis) is a technique used to
exaggerate subtle increase in tone, and is particularly
useful for assessing extrapyramidal tone increase. Ask the
patient to describe circles in the air with the contralateral
limb while you assess tone. A transient increase in tone
with this manœuvre (Froment’s) is normal.
• Roll the leg from side to side and then briskly flip the knee
up into a flexed position, observing the movement of the
foot. Typically, the heel moves up the bed, but increased
tone may cause it to lift off the bed due to failure of
• Support the patient’s leg, with both the knee and the
ankle resting in 90-degree flexion.
• Briskly dorsiflex and partially evert the foot, sustaining the
pressure. Clonus is felt as repeated beats of dorsiflexion/
• Ask the patient to make a fist and then to relax and open
their hand; watch for the speed of relaxation.
• Using the tendon hammer, percuss the belly of the thenar
eminence; this may induce contraction of the muscles,
causing the thumb to adduct, and you may witness
Decreased tone may occur in lower motor neurone lesions
and is usually associated with muscle wasting, weakness and
hyporeflexia. It may also be a feature of cerebellar disease or
signal the early phases of cerebral or spinal shock, when the
paralysed limbs are atonic prior to developing spasticity. Reduced
tone can be difficult to elicit.
Increased tone may occur in two main forms: spasticity and
Spasticity is velocity-dependent resistance to passive
movement: it is detected with quick movements and is a feature
of upper motor neurone lesions. It is usually accompanied by
weakness, hyper-reflexia, an extensor plantar response and
sometimes clonus. In mild forms it is detected as a ‘catch’ at
the beginning or end of passive movement. In severe cases
it limits the range of movement and may be associated with
contractures. In the upper limbs it may be more obvious
on attempted extension; in the legs it is more evident on
Tremor is an involuntary, oscillatory movement about a joint
or a group of joints, resulting from alternating contraction and
relaxation of muscles. Tremors are classified according to their
frequency, amplitude, position (at rest, on posture or movement)
hyperthyroidism and with excess alcohol or caffeine intake, and
is a common adverse effect of beta-agonist bronchodilators.
Essential tremor is the most common pathological cause of
tremor; it is typically symmetrical in the upper limbs and may
involve the head and voice. The tremor is noted on posture and
with movement (kinetic). It may be improved by alcohol and often
demonstrates an autosomal dominant pattern of inheritance.
Parkinson’s disease causes a slow (3–7 Hz), coarse, ‘pill-rolling’
tremor, worse at rest but reduced with voluntary movement. It is
more common in the upper limbs, is usually asymmetrical and
does not affect the head, although it may involve the jaw/chin
Isolated head tremor is usually dystonic and may be associated
with abnormal neck postures such as torticollis, antecollis or
Intention tremor is absent at rest but maximal on movement
and on approaching the target (hunting tremor), and is usually
due to cerebellar damage. It is assessed with the finger-to-nose
Other causes of tremor include hereditary or acquired
demyelinating neuropathies (such as Charcot–Marie–Tooth
disease) and are termed neuropathic tremors. Drugs commonly
causing tremor include sodium valproate, glucocorticoids and
Movement disorders, including tremor, are common functional
symptoms. They are often inconsistent and distractible, with
varying frequencies and amplitudes, and may be associated
These are classified according to their appearance.
Dystonia is caused by sustained muscle contractions, leading to
twisting, repetitive movements and sometimes tremor. It may be
focal (as in torticollis), segmental (affecting two or more adjacent
Chorea describes brief, jerky, random, purposeless movements
that may affect various body parts, commonly the arms.
Athetosis is a slower, writhing movement, more similar to
Ballism refers to violent flinging movements sometimes affecting
only one side of the body (hemiballismus).
Tics are repetitive, stereotyped movements that may be briefly
Tone is the resistance felt by the examiner when moving a joint
• Ask the patient to lie supine on the examination couch
and to relax and ‘go floppy’. Enquire about any pain or
limitations of movement before proceeding.
• Do not test every muscle in most patients; the commonly
tested muscles are listed in Box 7.9.
• Ask about pain that might interfere with testing.
• Observe the patient getting up from a chair and walking.
• Test upper limb power with the patient sitting on the edge
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