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Clinical Aspects of Movement Disorders:
Effects on Walking and Posture
Henrique Ballalai Ferraz and Roberta Arb Saba
Abstract
Movement disorders are a group of syndromes which includes parkinsonism,
chorea, dystonia, myoclonus, tremor, and tics. Many of the diseases of this group
manifest disturbances of gait and posture along with other abnormalities. Parkinsonism is characterized by rest tremor, muscular rigidity, bradykinesia, flexed
posture of the trunk, and loss of postural reflexes. Parkinson’s disease (PD) is the
most prevalent of the diseases of this group and patients usually manifest
problems of gait and posture in late phases. On the other hand, atypical parkinsonism diseases (multiple-system atrophy, progressive supranuclear palsy,
dementia with Lewy bodies, and corticobasal ganglionic degeneration) manifest
gait problems and falls very early and are much more incapacitating than
PD. Vascular parkinsonism manifests itself with lower limb rigidity and
bradykinesia and affects gait very early. Huntington’s disease is a genetic
disorder characterized by behavioral and cognitive disturbances associated
with chorea, dystonia, and loss of equilibrium. Sometimes, especially in subjects
with the juvenile form of Huntington’s disease, it may manifest with a very
severe parkinsonism.
Keywords
Movement disorders • Parkinsonism • Parkinson’s disease • Parkinson-plus
syndromes • Multiple-system atrophy • Progressive supranuclear palsy •
Dementia with Lewy bodies • Corticobasal ganglionic degeneration • Vascular
parkinsonism • Huntington’s disease
H.B. Ferraz (*) • R.A. Saba
Movement Disorders Unit – Department of Neurology, Universidade Federal de S~ao Paulo –
Escola Paulista de Medicina, S~ao Paulo, Brazil
e-mail: [email protected]; [email protected]
# Springer International Publishing AG 2017
F.A. Barbieri, R. Vitório (eds.), Locomotion and Posture in Older Adults,
DOI 10.1007/978-3-319-48980-3_2
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2.1
H.B. Ferraz and R.A. Saba
Introduction
Some of the diseases of the spectrum of movement disorders are associated with
abnormalities of posture and locomotion. We can mention the multiple forms of
parkinsonism, Huntington’s disease, and generalized dystonia, among others.
Posture and walking may be affected by the involuntary movements per se or by
degeneration or lesions of neural pathways involved in tonus and balance. In this
chapter we will present some of the diseases associated with abnormal involuntary
movements and impairment of posture and gait.
2.2
Parkinsonism
Parkinsonism is a syndrome characterized by the combination of bradykinesia, also
called akinesia, with any of the three: muscular rigidity, rest tremor, or impairment
of postural reflexes.
Bradykinesia is the reduction of the global repertoire of automatic movements,
and the decrease of the amplitude and the speed of the voluntary movements.
We can detect bradykinesia in a parkinsonian patient either by observing the lack
of facial expression while talking or listening with the examiner or by the reduced
arm and hand gestures during a conversation. In other words, bradykinetic patients
tend to have a poor repertoire of body language [1].
Muscular rigidity is observed by a resistance while manipulating a joint of a
limb. Resistance is present both during passive flexion and extension of a limb.
We can also feel the sensation of being manipulating a lead pipe, and sometimes
this is associated with the clinical sign called “cogwheel rigidity.” This is perceived
as an intermittent and very short-lived release of the resistance during a full
extension or flexion movement [2].
Rest tremor can be observed in any part of the body. Hand tremor manifests as a
rhythmic flexion and extension of the fingers and it is called “pill-rolling tremor.”
Tremor can also affect the lower limbs, trunk, chin, head, and larynx. It may cycle
in a fashion varying from 4 to 6 Hz. Sometimes, parkinsonian patients may present
with a postural and kinetic hand tremor associated or not with the resting tremor [1].
Impairment of postural reflexes is characterized by an inability to correct sudden
shifts of the normal upright position. People with this kind of impairment usually
have frequent falls and assume a stooped posture. The more the trunk is bent
forward, the higher the risk of having falls [2].
The combination of the four cardinal symptoms results in the typical parkinsonian gait and posture. Patients tend to flex the trunk forward and the arms are flexed
close to the level of the hip. The arms do not harmonically sway while the body is
moving. The turning of the body is made by slow and fragmented successive short
movements. The length of the steps is very short, and heels drag to the floor.
Sometimes, due to the flexed posture, parkinsonian people tend to fall forward,
and to avoid it they shift the slow steps to a running pace. This is called festination
or festinating gait and when present is a classical manifestation of parkinsonism.
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Clinical Aspects of Movement Disorders: Effects on Walking and Posture
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Too many clinical conditions may precipitate parkinsonism. The most frequent
is idiopathic Parkinson’s disease (PD). Other situations are pharmacologically
induced parkinsonism (mainly antipsychotics), metal or poison exposure (manganese, pesticides, carbon monoxide), vascular lesions of the central nervous system
(CNS), hereditary diseases, some dementia syndromes (Alzheimer’s disease and
frontotemporal dementia), and other degenerative diseases called atypical parkinsonism or Parkinson-plus syndromes (progressive supranuclear palsy, multiplesystem atrophy, dementia with Lewy body, and corticobasal ganglionic degeneration). We will discuss some of the specific diseases associated with parkinsonism.
2.2.1
Parkinson’s Disease
PD is characterized by motor and non-motor symptoms and is associated with a
progressive degeneration of neurons of the CNS. The degenerative process seems to
start in the medulla and pons and progresses to a wider distribution in the encephalon. Motor symptoms (parkinsonism) begin when dopaminergic neurons of the
substantia nigra are affected. Nigral neurons become progressively scarce and
there is the presence of Lewy bodies, an eosinophilic intraneuronal inclusion, the
classical pathological hallmark of PD [3].
PD may affect adult individuals of both gender and at any age, although most
frequently those with 50 or more years of age. Unilateral symptoms are the most
common way of starting the disease, and the other side tends to be affected in the
following months or years. Patients may manifest rest tremor in one arm or feel
difficulty in moving one limb. In a few months, the symptoms tend to become more
and more intense and eventually will interfere with daily activities. Difficulty in
arising from chair or bed is also common complaints in the early phase of the
disease. Gait and postural impairment are usually present after a few years of
onset [4].
Fully manifested PD includes bradykinesia, rigidity, and postural abnormalities
with gait and balance impairment. PD patients tend to have a shuffling gait and a
tendency to have falls. Festinating gait is a classic parkinsonian sign and results
from the combination of the flexed forward posture, the short steps, and the loss of
postural reflexes. In this case, patients tend to accelerate the steps in order to catch
up the center of the gravity abnormally placed forward.
Freezing of gait may be present in many patients and is characterized by a
difficulty in taking out the feet off the floor while attempting to start the gait.
Freezing of gait is more frequent when patients try to turn around or during the
passage of narrow spaces. The “pull test” is the clinical way to detect impairment of
postural reflexes. Patients are put standing with feet comfortably apart. The doctor
stands backward and pulls him or her briskly and forcefully. The balance is
considered impaired if the patient has to move backward for at least three steps
of recovery. In severely affected patients, the examiner has to catch the patients to
prevent the fall.
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H.B. Ferraz and R.A. Saba
Considering only the clinical presentation of PD, there are two main subtypes: a
tremor-dominant form and a postural impairment with gait disturbance (PIGD).
The first one is characterized by a more benign progression, with excellent response
to levodopa and late development of cognitive decline. The PIGD form has a faster
progression, with less response to levodopa and early development of falls and
cognitive decline [5].
Non-motor symptoms include mood disorders (depression), cognitive decline
(in late stages of the disease), olfaction impairment, and disturbances of autonomic
function (also in late stages). Sleep disorders, especially rapid eye movement
behavioral disorder, are quite common and may be present years before the
development of motor symptoms.
Treatment is based in dopaminergic reposition. Levodopa is the mainstay of
pharmacological treatment. The drug is taken by mouth and in the brain, particularly in neuron and glial cells, is converted into dopamine. If the conversion to
dopamine is made by a nigral dopaminergic neuron, it can be stored in vesicles
inside the synaptic terminal and can be released afterward. If the conversion is
made in glial cells or in non-dopaminergic neurons, dopamine cannot be stored and
is immediately released to the postsynaptic receptor. Long-term use of levodopa
may be associated with motor fluctuations and dyskinesias. These complications are
more common if higher doses of levodopa are used (more than 500 mg a day) and if
patients are more severely affected. Dopamine agonists may be also prescribed and
act directly at the postsynaptic receptors of striatum. Most commonly prescribe
dopamine agonists are pramipexole, ropinirole, and rotigotine. Other drugs are
entacapone (catechol-o-methyltransferase inhibitor), rasagiline or selegiline
(monoamine oxidase inhibitor), amantadine (glutamate receptor inhibitor), and
anticholinergics [6].
Surgery treatment is indicated when patients are optimized receiving levodopa
combined with other adjuvant medications but present uncontrolled motor
fluctuations and dyskinesias. There are two main surgery procedures: ablative
lesions and deep brain stimulation (DBS). The targets indicated are thalamic nuclei,
subthalamic nucleus, and globus pallidus interna [7].
Physical and speech therapy are useful for any phase of the disease, but are
particularly indicated in patients experiencing balance disturbances and fall (physical therapy) and those with swallowing difficulties and significant dysarthrophonia
(speech therapy).
2.2.2
Atypical Parkinsonism
Atypical parkinsonism is also called Parkinson-plus syndromes since most of the
patients of this group manifest motor symptoms similar to PD. The difference
between PD and these diseases is that atypical parkinsonian patients manifest
other neurological abnormalities, such as cerebellar ataxia, autonomic dysfunction,
paralysis of the vertical gaze, early-phase cognitive decline, and behavioral
disturbances.
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All the diseases of this group are neurodegenerative in origin and display
neuronal loss in different structures of the central nervous system. None of the
diseases of this group have a curative or evolution-modifying pharmacotherapy.
Levodopa rarely induces some benefit to this group of patients. Alpha-synuclein
inclusions are seen in multiple-system atrophy and dementia with Lewy bodies,
while tau protein fibrils are seen in progressive supranuclear palsy and corticobasal
ganglionic degeneration.
2.2.3
Multiple-System Atrophy (MSA)
MSA is characterized by the combination of parkinsonian signs with autonomic,
pyramidal, and cerebellar signs. There are two forms: MSA-P (parkinsonism), with
a predominance of parkinsonian signs, and MSA-C (cerebellar), where there is a
predominance of cerebellar signs. The most common form is the MSA-P. The most
common signs are dysautonomic: postural hypotension, constipation, urinary
incontinence, erectile dysfunction, and cold and cyanotic extremities (“cold blue
hands”). Parkinsonian signs are bilateral from the start with the absence of rest
tremor. Gait ataxia and balance disturbances can arise from the very beginning, as
well as frequent falls. Pyramidal signs as the Babinski sign are present; dysphagia
and dysarthria also manifest in the early stage. Other symptoms such as laryngeal
stridor, trunk dystonia, and cerebellar signs may be observed. Neuroimaging studies
show atrophy of the pons and the cerebellum and usually the presence of the
“hot-cross bun signal,” a characteristic hyperintensity on FLAIR of the transverse
fibers of the pons and cerebellar peduncle with normal sign of the corticospinal tract
and pontine tegmentum [8].
2.2.4
Progressive Supranuclear Palsy (PSP)
It was described in the 1960s by Steele, Richardson, and Olszewski. Patients
manifest the first symptoms around 50 to 60 years which are characterized by gait
disturbance block and trunk hyperextension, postural instability with falls, lower
vertical gaze palsy, and cognitive impairment and do not respond to levodopa
treatment. The classic form or Richardson syndrome occurs in about 55 % of
subjects and presents the peculiar symptoms of PSP, as parkinsonism, paralysis
of vertical gaze, bilateral bradykinesia, frequent falls, and cognitive decline.
PSP-parkinsonism (PSP-P) is the way of presentation in 30 % of the subjects and
the clinical picture is very similar to PD, and only on late stages patients develop
gaze palsy and prominent cognitive decline. Fifteen percent of PSP patients present
atypical forms. On imaging techniques, particularly in magnetic resonance imaging
(MRI), enlargement of the third ventricle and atrophy of midbrain are prominent in
late phases of the disease [9].
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2.2.5
H.B. Ferraz and R.A. Saba
Dementia with Lewy Bodies (DLB)
DLB starts between 60 and 70 years and is characterized by the presence of
parkinsonian signs closely resembling DP associated with cognitive decline.
Cognitive symptoms precede or follow up to 12 months after parkinsonism starts.
The patient may present, in addition to parkinsonism and dementia, behavioral
symptomatology such as hallucinations and delusions, with fluctuation of these
symptoms (worse at night). It is quite common patients manifest great sensitivity to
the exposure to neuroleptics (rapid development of severe stiffness and tremor) and
rapid eye movement (REM) sleep behavioral disorder [10].
2.2.6
Corticobasal Ganglionic Degeneration (CBGD)
CBGD is characterized by progressive and asymmetric stiffness associated with
upper limb apraxia. The phenomenon of “alien limb” is commonly present and
characterized by involuntary movements of the upper limb, with levitation.
Most patients present aphasia, unilateral dystonia, myoclonus, and rapidly progressive dementia of the frontotemporal type. Asymmetric atrophy of the cerebral
hemisphere, mainly in the parietal region, is usually seen on MRI studies [1].
2.2.7
Vascular Parkinsonism
Vascular parkinsonism (VP) accounts for 2.5–5 % of the total cases of parkinsonism. VP patients exhibit lower disease duration, older age at onset, and higher
frequency of cardiovascular risk factors. This disease can be clinically distinguished from PD based on sudden onset of parkinsonism at older age, characterized
by lower body predominance, urinary incontinence, pyramidal signs, postural
instability with freezing of gait and falls, and dementia. The upper limbs in VP
are less symptomatic in terms of parkinsonism throughout the course of disease.
This is in clinical contrast to PD, in which patients generally present with tremor,
rigidity, or slowness of the upper limbs. Thus, VP is also called “lower body or
lower half” parkinsonism. VP patients developed cognitive impairment in comparison with same age individuals. These patients had a global pattern of cognitive
impairment, including executive function, verbal memory, and language [11].
The main differential diagnosis of VP is PD, frontal lobe tumors, obstructive
hydrocephalus, normal pressure hydrocephalus, and progressive supranuclear palsy.
Imaging studies serve two purposes in a VP patient. First, it rules out other
causes of parkinsonism, both degenerative (progressive supranuclear palsy) and
secondary (tumors, hydrocephalous). Second, it may show ischemic lesions to
support the clinical diagnosis. MRI or computerized tomography (CT) is supportive, but not conclusive, of the diagnosis of VP because there are no characteristic
features of VP in CT/MRI. However, white matter lesions and lacunes are also
common observations among the older people who do not have parkinsonism.
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This causes difficulty in determining the etiological mechanisms of VP. A study
showed that most patients with VP had brain MRI changes with multiple lacunar
infarcts (66.7 %) or extensive white matter (WM) disease (26.7 %) [12]. Others
investigated the WM microstructure using diffusion tensor imaging in patients with
VP, and specific fiber tract involvement, with respect to clinical severity, showed
disruption of the microstructural organization of frontal lobe WM is associated with the
severity of VP [13]. These findings are in accordance with the frontal lobe disconnection hypothesis for gait problems and reinforce the paradigm that the involvement of
fibers related to the prefrontal cortex is crucial for the core features of VP [13].
Clinical features of VP phenotype are early postural instability and gait difficulty
(PIGD). PIGD as the initial symptom is significantly more common in VP than in
PD. Gait disturbance was reported as the initial symptom in 90 % of patients with
VP as compared to 7 % of patients with PD [14]. The gait in VP is like a
“parkinsonian-ataxic” gait. The stance is wide based. The posture is upright at
least in the earlier stages and a much lesser degree of flexion is seen at the knees and
hips than in PD. Steps are slow, short, and with a tendency to shuffle, particularly at
the start and while turning the corners. Freezing of gait can be seen, but festination
is absent. In severe cases, the patient is unable to initiate a step and the feet
remained fixed to the floor (magnetic gait). Postural instability and falls dominate
the gait at this advanced stage and render the patient unable to walk or even stand
without support. Another factor contributing to the impaired mobility in advanced
stages is truncal ataxia. These patients also have truncal and axial immobility.
Sideways turning of the head is limited and patients turn their heads, neck, and
shoulder in block to be able to look sideways. The change of posture while lying in
bed is also difficult and limited. An interesting feature in obvious PIGD, at least in
the earlier stages, is that many patients can perform simple tasks with their legs, like
imitating bicycling or walking movements, when seated or lying. However, these
movements are also slow.
The treatment should be directed at secondary stroke prevention in an attempt to
halt further disease progression although, understandably, it would not reverse or
provide symptomatic relief to the existing clinical manifestations. The management
of conventional vascular risk factors such as diabetes, hypertension, dyslipidemia,
and smoking cessation would probably have the maximal impact in this approach to
treatment. The levodopa response rates in VP vary from 20 to 40 %. A dose of up to
1000 mg/day should be given for at least 3 months before labeling the patient as a
non-responder or poor responder. In good responders the duration of sustained
response is typically less than in PD, with the drug becoming non-beneficial after
one to two years [15].
2.3
Huntington’s Disease
Huntington’s disease (HD) is a progressive neurodegenerative disease, rare and
fatal, characterized by a movement disorder mostly manifesting as choreic and
dystonic movements, psychiatric abnormalities, and cognitive decline.
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H.B. Ferraz and R.A. Saba
HD is a genetic disease of autosomal dominant inheritance. An expansion occurs
in the number of repeats of CAG pair of nitrogenous bases (adenine, cytosine,
guanine) in unstable regions of DNA HTT gene, which is located on the short arm
of chromosome 4 (4p16.3). Twenty-seven or fewer repetitions of CAG have a
normal phenotype. Intermediate alleles with 27 to 35 CAG repeats are unstable
and may be transmitted as an expanded allele to offspring. However, the carriers of
the normal intermediate allele also have a normal phenotype. These intermediate
expanded alleles occur, particularly, during male gametogenesis, as the same is
subjected to a larger number of division cycles and duplication of genetic material.
Thus, there is a greater likelihood of an error in DNA replication during spermatogenesis, which increases the risk of mutated alleles to be paternal inheritance [16].
Alleles with 36–39 CAG repeats indicate incomplete penetrance and can generate
both normal phenotypes with the disease. Alleles with more than 39 CAG repeats
have complete penetrance and inevitably cause, in any phase of life, the phenotype
of HD.
Symptoms usually start between ages 35 and 55 and duration of disease can vary
from 15 to 20 years. In some cases, it may manifest after 80 years of age or earlier,
in adolescents or children, due to anticipation phenomenon, which occurs in 20 %
of cases. Due to the variability of the clinical signs and symptoms, the molecular
test is required for the diagnosis.
The most frequent isolated initial complaint is the lack of “coordination” and
occasional involuntary tremors in several body segments, which usually can be
attributed to the presence of chorea. Other early motor abnormalities include
saccadic eye movements, interrupted or slow, inability to sustain tongue protrusion, and difficulty in performing rapid alternating movements. Behavioral
changes are often reported to precede movement disorder over a decade.
Symptoms of emotional nature or personality changes may antedate these
movements in at least half of patients with DH. Patients are excessively irritable,
impulsive, unstable, and aggressive. The most common early symptoms are
mental depression. In some of the cases, the opening frame can be a frank
psychosis.
The most striking feature of HD is the presence of choreic movements seen in
approximately 90 % of the affected individuals. At first, chorea may be mild,
affecting only the face or distal portions of limbs, but, with time, it becomes
widespread, interfering with any voluntary movement [17]. Gradually, with the
progress of the disease, the patients are becoming slower in nature, taking an
athetoid character, and, subsequently, dystonic [18]. Other involuntary movements,
such as tremors and intention myoclonus, can rarely be present. Dysarthria is
another prominent symptom that appears early in the course of disease, as slowing
or hesitancy in speech, which gradually becomes explosive, irregular, and
interspersed with long silences, and an increase of chances for a complete disorganization and mutism. Dysphagia, common in the advanced stages of HD, is often
responsible for choking and aspiration, bronchopneumonia aspiration, being
reported in up to 85 % of mortality. The causes of death are related complications
of immobility, such as food or trauma, and asphyxia aspirations. The patient’s gait
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Clinical Aspects of Movement Disorders: Effects on Walking and Posture
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is characterized, constantly parasitized, by choreic movements, taking uncoordinated character in appearance, and it can become impossible. Patients also exhibit
postural instability and primary changes in the balance, with frequent falls and
fractures. Bradykinesia, with or without stiffness, occurs in the later stages of
disease with extreme slowness of all movements. This symptom is directly related
to the disability of patients and it occurs regardless of chorea [17]. Sphincter
incontinence, both urinary and anal, is common, especially in the terminal stages
of HD. There is evidence of autonomic dysfunction as hyperhidrosis and changes in
blood pressure regulation. Generalized tonic-clonic seizures may occur in up to 3 %
of adults with DH and in approximately 40 % of patients with early disease onset
(under 20), as other types of seizures can happen [18].
Psychiatric and cognitive changes may precede the motor manifestations,
accompany them, or occur after [19]. Dementia is considered one of the cardinal
signs of the disease. Patients with DH are more impaired in learning, mental
flexibility, and attention. Executive function is compromised and is noted early,
even in the absence of complaints from patients or family members. It includes
difficulty in planning, organizing, and scheduling activities. The executive
functions are related to the frontal lobe and its connections. Cognitive functions
are more strongly correlated with the functional capacity of the motor symptoms.
The psychiatric symptoms occur in about 35–70 % of cases. Patients may present
frameworks of personality change, mood disorders, and psychosis. The most
commonly found personality changes are psychiatric and include irritability, apathy, emotional lability, impulsivity, and aggressiveness. Depression may precede
motor symptoms. The frequency of suicides in HD is four to six times higher than
that in the general population. Suicidal ideation is present in approximately 10 % of
individuals diagnosed with HD. Episodes of mania can also be found, less commonly, and schizophreniform psychosis occurs in 6–25 % of cases; this is
characterized by paranoid tables with persecutory delusions, jealousy, and auditory
hallucinations. Other psychiatric conditions include irritability, agitation and
aggression, disorder and obsessive-compulsive behavior, psychosomatic
complaints, anxiety, sexual paraphilias, and behavioral changes [20].
Symptomatic treatment reduces motor and behavioral symptoms and thus
maximizes functional capacity of the affected individual. The treatment is done
with chorea antagonists dopaminergic with high affinity for D2 receptors. Among
the drugs which may be used to control abnormal movements, there are risperidone
and olanzapine (typical neuroleptic), and haloperidol (atypical neuroleptic).
Tetrabenazine is also indicated for the control of choreic movements. However,
due to the high incidence of depression in patients treated with this drug, its use is
limited. The dose should be individualized, starting always with low doses and
increasing until the control of involuntary movements is satisfactory from a functional point of view [21]. Patients generally tolerate high doses of conventional
neuroleptics, showing no symptoms of impregnation. The inhibitors of N-methylD-aspartate (NMDA) glutamate receptors, such as amantadine, can be used for
the motor’s movement control. Depression usually responds to classical
antidepressants such as selective inhibitors or serotonin reuptake dual inhibitors.
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H.B. Ferraz and R.A. Saba
Excessive irritability can be treated with benzodiazepines. Aggressive patients can
benefit from both antidepressants and neuroleptics. There is not a specific treatment
for HD dementia [21].
2.4
Final Remarks
Gait and balance are usually impaired in many neurodegenerative diseases, but
parkinsonism and Huntington’s disease are the most frequent, with the higher
impact on daily activities of patients. Although these conditions usually do not
have a definite treatment to control axial symptoms, pharmacological and rehabilitation approaches are essential to improve quality of life of the patients.
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