Apraxia
Synonyms and keywords: Dyspraxia

# Overview
Praxis, a Greek work for act, work, or deed, is the ability to perform the learned movements. It usually comprises of three components, namely, ideation (what to do), motor planning (how to do), and execution (performing the movement correctly), that results in purposeful movements. Apraxia, however, is the inability to execute these skilled and learned purposeful movements when there is a breakdown in any component of praxis. This disorder makes it difficult to perform daily tasks and negatively impact the quality of life. Apraxia, a complex neurological disorder, with cognitive-motor dysfunction may be acquired or developmental. It can occur as a result of brain trauma/disease, and higher motor functional neuronal pathways damage in the setting of preserved comprehension, coordination, motivation, and elementary sensory and motor systems. The most common types of apraxia are 'Ideational' and 'Ideomotor'.

# Historical Perspective
- Steinthal introduced the term apraxiae (Greek word meaning inaction) in 1871. However, a German physician, Hugo Lipmann first established the conceptual knowledge and published complete description of apraxia after studying the gestures in a 48-year old stroke patient who had a left hemispheric stroke.
- Lipmann noticed that, despite of resolution of the paresis, the patient was unable to perform tasks such as buttoning the shirt, with no affect on spontaneous movements, and doing simple tasks on command. He observed this phenomenon specifically in patients with left hemispheric lesions. He also concluded that the planning of the motor movements occurs in the motor area of the left side of the brain. Lipmann further proposed that the 'praxis' information flows from the posterior brain areas (parietal and occipital lobes) to the anterior (motor cortex).
- The major subtypes classified by Lipmann were ideational, ideomotor, and limb-kinetic apraxia.
- One of the behavioral neurologist, Norman Geschwind, presented that the superior longitudinal fasciculus involvement disconnects the Wernicke's area are from the left premotor cortex, leading to 'apraxia'

# Classification
- Ideomotor apraxia:
Most common type of apraxia.
Decreased performance of skilled motor performances despite integral language, sensory and motor function.
Seen more frequently in neurodegenerative disorders and stroke patients.
It can be classically demonstrated when a patient questioned verbally to make a motion with a limb. Patients with Ideomotor apraxia display spatial and temporal errors, inconvenient timing, amplitude, sequencing, configuration,  limb position in space.
It is an inability to carry out, learned motor acts, command, adequate motor, and sensory abilities.
Ideomotor apraxia can be due to cerebral damage in numerous areas, including the left parietal lobe, the intrahemispheric association fibers, the dominant hemisphere motor association cortex, and the anterior corpus callosum.
Patients often use their arm as an object relatively than indicating how to use the object . Patients are frequently able to achieve the same acts without struggle in their daily lives. This process has been called the "voluntary-automatic dissociation".
These patients have a deficiency in their skill to plan or ample motor actions that depend on semantic memory. They can describe how to achieve a response, but incapable to "imagine" or do the movement. Though the capability to perform an act inevitably when cued remains complete, this is recognized as automatic-voluntary dissociation.In Ideomotor apraxia, there is difficulty or inability to execute familiar or learned movements on command despite of understanding the command and willingness to perform that action. The characteristic of this type of apraxia is the inability to a transitive movement. For example, the person can describe how a tool such as comb is used, but, when asked to use that tool, he is unable to perform the task (i.e. combing the hair) using the comb
- Most common type of apraxia.
- Decreased performance of skilled motor performances despite integral language, sensory and motor function.
- Seen more frequently in neurodegenerative disorders and stroke patients.
- It can be classically demonstrated when a patient questioned verbally to make a motion with a limb. Patients with Ideomotor apraxia display spatial and temporal errors, inconvenient timing, amplitude, sequencing, configuration,  limb position in space.
- It is an inability to carry out, learned motor acts, command, adequate motor, and sensory abilities.
- Ideomotor apraxia can be due to cerebral damage in numerous areas, including the left parietal lobe, the intrahemispheric association fibers, the dominant hemisphere motor association cortex, and the anterior corpus callosum.
- Patients often use their arm as an object relatively than indicating how to use the object . Patients are frequently able to achieve the same acts without struggle in their daily lives. This process has been called the "voluntary-automatic dissociation".
- These patients have a deficiency in their skill to plan or ample motor actions that depend on semantic memory. They can describe how to achieve a response, but incapable to "imagine" or do the movement. Though the capability to perform an act inevitably when cued remains complete, this is recognized as automatic-voluntary dissociation.In Ideomotor apraxia, there is difficulty or inability to execute familiar or learned movements on command despite of understanding the command and willingness to perform that action. The characteristic of this type of apraxia is the inability to a transitive movement. For example, the person can describe how a tool such as comb is used, but, when asked to use that tool, he is unable to perform the task (i.e. combing the hair) using the comb
- Ideational apraxia:
As the name depicts, the problem is in conceptualization of the task.
The person may be able to name the objects correctly but fails to coceptualize how that object is used.
Inability to create a plan for or idea of a specific movement, for example, "pick up this pen and write down your name"
- As the name depicts, the problem is in conceptualization of the task.
- The person may be able to name the objects correctly but fails to coceptualize how that object is used.
- Inability to create a plan for or idea of a specific movement, for example, "pick up this pen and write down your name"
- Constructional apraxia:
It is a condition resulting from neurological damage, which is demonstrated by the inability to construct and copy to command two- and three-dimensional stimuli.
Constructional apraxia has been a classic sign of a parietal lobe lesion, and as a valuable tool to escalate the spatial abilities functioned by this lobe.
It has become gradually clear that Constructional apraxia is a complex construct that can be observed with very different tasks that are only slightly interrelated, and hit various kinds of visuospatial, attentional, perceptual, planning, and motor mechanisms.
The patient with constructional apraxia is unable to construct, draw, or copy simple configurations; for example, intersecting shapes; they have trouble drawing basic shapes or copying a simple diagram.
inability to draw or construct simple configurations
- It is a condition resulting from neurological damage, which is demonstrated by the inability to construct and copy to command two- and three-dimensional stimuli.
- Constructional apraxia has been a classic sign of a parietal lobe lesion, and as a valuable tool to escalate the spatial abilities functioned by this lobe.
- It has become gradually clear that Constructional apraxia is a complex construct that can be observed with very different tasks that are only slightly interrelated, and hit various kinds of visuospatial, attentional, perceptual, planning, and motor mechanisms.
- The patient with constructional apraxia is unable to construct, draw, or copy simple configurations; for example, intersecting shapes; they have trouble drawing basic shapes or copying a simple diagram.
- inability to draw or construct simple configurations
- Buccofacial or orofacial apraxia:
These patients cannot convey facial movements on requests, such as voluntary movements of the tongue, cheeks, lips, pharynx, or larynx on command, for example, include licking lips, whistling, coughing, or winking).
- These patients cannot convey facial movements on requests, such as voluntary movements of the tongue, cheeks, lips, pharynx, or larynx on command, for example, include licking lips, whistling, coughing, or winking).
- Limb-kinetic apraxia:
It is the failure to make precise movements with an arm, finger, or leg. For example, a person may have trouble tying their shoes, waving hello, or typing on a computer.
Inability to make fine, precise movements with a limb
- It is the failure to make precise movements with an arm, finger, or leg. For example, a person may have trouble tying their shoes, waving hello, or typing on a computer.
- Inability to make fine, precise movements with a limb
- Gait apraxia:
Apraxia of gait is a rare locomotion syndrome categorized by the incapability of lifting the feet from the floor regardless of discontinuous stepping action.
The accountable site of lesions is in the basal ganglia and frontal lobe.
- Apraxia of gait is a rare locomotion syndrome categorized by the incapability of lifting the feet from the floor regardless of discontinuous stepping action.
- The accountable site of lesions is in the basal ganglia and frontal lobe.
- Task-specific apraxia:
These include-
Sitting apraxia
Dressing apraxia
Eyelid opening apraxia
-culomotor (difficulty moving the eye)
- These include-
Sitting apraxia
Dressing apraxia
Eyelid opening apraxia
-culomotor (difficulty moving the eye)
- Sitting apraxia
- Dressing apraxia
- Eyelid opening apraxia
- oculomotor (difficulty moving the eye)

# Pathophysiology
- 'Praxis' comprises three components, which include ideation, motor planning, and execution to carry out the purposeful movement. There are particular regions of the brain that represent specific component functions, and these regions together work as a praxis system to process and execute a purposeful movement. Dysfunction in any of these regions, namely, frontal and parietal cortex, basal ganglia, and the white matter which connects theses areas, leads to apraxia.
- The movements which requires tools are transitive movements, and the ones which do not require tools are intransitive. The intransitive movements are gestural which can be meaningful (communicative), or meaningless movements (not representational). In apraxia, transitive movements are affected more frequently as compared to intransitive movements.
- The observations of the patients in the clinical practice is the basis of most of the knowledge about 'apraxia'. Apraxia has been mostly seen in chronic left hemispheric lesions and Alzheimer's disease. The left hemispheric lesions cause more difficulty to perform transitive movements, as compared to intransitive movements and imitating gestures. Left hemisphere has a major role in 'praxis' and this may be due to specific stored representations in left hemisphere and their retrieval. On the other hand, Alzheimer's patients have preserved transitive movements, but shows deficits in gestures. Therefore, the type of apraxia depends on the type of neurological disease and the area of the brain affected by it.
- Different brain regions which have role in cognition and movement are involved in complex 'Praxis' movements. The conceptualization of a purposeful task involves prefrontal, left premotor, middle temporal and parietal areas of the brain.
- Neuroimaging studies have been done to investigate praxis correlations, but studies done so far vary widely on focus areas of praxis. One of the study reported left temporal lobe correlation with praxis because of its role in somatic memory retrieval. Left premotor cortex, left parietal lobule, and parietal cortex have also been shown to have a role in praxis as they are involved in knowledge of tools and their use, grasping movements, and spatiotemporal information integration, respectively. Stronger left lateralization (especially posterior parietal and premotor cortex) for gesture production in praxis has been suggested by neuroimaging studies.

# Causes
- The most common causes of apraxia are:
Neurodegenerative illness
Brain tumor
Dementia
Stroke
Traumatic brain injury
- Neurodegenerative illness
- Brain tumor
- Dementia
- Stroke
- Traumatic brain injury

# Epidemiology and Demographics
- The information available on the incidence of apraxia in adults is limited.
- As apraxia is most common in children, the incidence is approximately 1 to 2 children per 1,000 (0.1%0.2%) worldwide.
- Prevalence rates of  apraxia range among 0 and 34% for patients with Right hemisphere stroke and 2857% for patients with Left hemisphere stroke.Real tool-use loss prevalence rates were stated with 2554% impaired level of patients.
- Apraxia commonly affects individuals older than 50 years of age. Apraxia affects men and women equally

# Differentiating Apraxia from Other Diseases

# Risk Factors
- Apraxia is a rare disease caused by stroke; it has the same risk factors as a stroke.
High blood pressure
High cholesterol
Diabetes
Smoking
Prior stroke or cardiovascular disease
Prior transient ischemic attack (TIA)
Dialysis treatment
- High blood pressure
- High cholesterol
- Diabetes
- Smoking
- Prior stroke or cardiovascular disease
- Prior transient ischemic attack (TIA)
- Dialysis treatment

# Screening
- There is insufficient evidence to recommend routine screening for apraxia.

# Natural History, Complications, and Prognosis
- The symptoms of apraxia typically develop during early or later years depending on the cause and the location affected.
- Often, patients with apraxia are not aware of their shortfalls. Therefore, the history of a patient's capability to accomplish skilled movements should be obtained from the patient's caregiver or the patient himself.
- Caregivers should be asked about the capability of patients to perform activities of daily living and perform tasks involving household tools such as using a toothbrush, knife, and fork appropriately, using kitchen utensils correctly and safely to prepare a meal; using tools such as scissors or hammer correctly.
- Caregivers should also be asked about the whole activity level of the patient and whether decreases in his or her total actions have happened.
- The patient may sit on the couch and watch television without showing interest in essential activities he or she use to do in the past.
- This indifference can be related to many kinds of brain dysfunction, but it sporadically occurs because the patient is incapable of performing his or her usual activities.
- Common complications of apraxia include:
Broca's Aphasia
Acalculi
Right-left Confusion
Alexia with agraphia
Wernicke's Aphasia
- Broca's Aphasia
- Acalculi
- Right-left Confusion
- Alexia with agraphia
- Wernicke's Aphasia
- Patients with apraxia are not able to do things independently and may distress carrying out everyday responsibilities. Activities should be avoided that can lead to injury and take the appropriate safety actions. Over-all, patients with apraxia rely on others for their daily activities and need at least some notch of command; skilled nursing care may be obligatory. Patients with the tumor or degenerative diseases usually develop into amplified levels of dependence.
- The prognosis for individuals with apraxia varies. With therapy, some patients improve significantly, while others may show very little improvement. Some individuals with apraxia may benefit from the use of a communication aid.

# Diagnosis
- Many tests have been developed to evaluate apraxia but most are difficult to apply in clinics as they are not rapid tests. Additionally, most of those lack in sensitivity and validity.
De Renzi ideomotor apraxia test for ideomotor apraxia assessment, can be tested in either side brain damage. It is a 24-item scale test.
Test of upper limb apraxia (TULIA) is a 48 item test, is preferred test as it has a good validity and reliability. It can be used to test-
non-symbolic (meaningless)
intransitive (communicative)
transitive (tool-related) gestures.20
Apraxia Screen of TULIA (AST) is a short bedside test with 12 items, with a high sensitivity and specificity. The basis of this test is TULIA test.
- De Renzi ideomotor apraxia test for ideomotor apraxia assessment, can be tested in either side brain damage. It is a 24-item scale test.
- Test of upper limb apraxia (TULIA) is a 48 item test, is preferred test as it has a good validity and reliability. It can be used to test-
non-symbolic (meaningless)
intransitive (communicative)
transitive (tool-related) gestures.20
- non-symbolic (meaningless)
- intransitive (communicative)
- transitive (tool-related) gestures.20
- Apraxia Screen of TULIA (AST) is a short bedside test with 12 items, with a high sensitivity and specificity. The basis of this test is TULIA test.
- Physical examination of patients with Apraxia  is usually dependent on what type of Apraxia they have for example Ideomotor apraxia, Buccofacial apraxia, and Constructional apraxia.
Ideomotor apraxia
Patients with ideomotor apraxia are tested based on the physical examination performed at the bedside with simple tests for the capability to use tools.
For example, the patients cannot hammer a nail into the (unreal) wall in front of them; patients are given a pair of scissors to cut a piece of paper.
However, different pantomimes could be made, including cutting with a saw, brushing teeth, peeling a potato or whipping eggs with an eggbeater.
Any error in carrying out the above activities indicates a loss of familiarity about the movement to be completed.
The response is recorded as an error.
Buccofacial apraxia
Patients cannot do skilled actions.
Constructional apraxia
Failure to copy or draw quality images.
Localizes lesions involving frontal or parietal area.
- Ideomotor apraxia
Patients with ideomotor apraxia are tested based on the physical examination performed at the bedside with simple tests for the capability to use tools.
For example, the patients cannot hammer a nail into the (unreal) wall in front of them; patients are given a pair of scissors to cut a piece of paper.
However, different pantomimes could be made, including cutting with a saw, brushing teeth, peeling a potato or whipping eggs with an eggbeater.
Any error in carrying out the above activities indicates a loss of familiarity about the movement to be completed.
The response is recorded as an error.
- Patients with ideomotor apraxia are tested based on the physical examination performed at the bedside with simple tests for the capability to use tools.
- For example, the patients cannot hammer a nail into the (unreal) wall in front of them; patients are given a pair of scissors to cut a piece of paper.
- However, different pantomimes could be made, including cutting with a saw, brushing teeth, peeling a potato or whipping eggs with an eggbeater.
- Any error in carrying out the above activities indicates a loss of familiarity about the movement to be completed.
- The response is recorded as an error.
- Buccofacial apraxia
Patients cannot do skilled actions.
- Patients cannot do skilled actions.
- Constructional apraxia
Failure to copy or draw quality images.
Localizes lesions involving frontal or parietal area.
- Failure to copy or draw quality images.
- Localizes lesions involving frontal or parietal area.
- There are no ECG findings associated with apraxia.
- There are no x-ray findings associated with apraxia.
- There are no echocardiography/ultrasound findings associated with apraxia.
- Brain CT scan may be helpful in the diagnosis of apraxia to evaluate for possible mass lesion or atrophy
- Brain MRI may be helpful in the diagnosis of apraxia. Findings on MRI diagnostic of apraxia include atrophy, ischemic changes, and mass lesion.
- There are no other imaging findings associated with apraxia.
- Diagnostic study PET may be helpful in the diagnosis of apraxia.

# Treatment
- Generally, treatment for individuals with apraxia includes physical therapy, occupational therapy or speech therapy. If apraxia is a symptom of another disorder (usually a neurologic disorder), the underlying disorder should be treated.
- No standardized treatment is available for apraxia. The frequency of limb apraxia in left hemispheric stroke patients is reported to be nearly 51%, and, hence, the therapeutic efforts are so far mostly concentrated towards stroke patients (left hemispheric stroke patients). Based on the studies, following treatment modalities have been considered so far-
Rehabilitative treatment- 30 sessions, each lasting 50 minutes, 3 times weekly have been tried.
Behavioral training Program-These include gesture-production exercises.
- Rehabilitative treatment- 30 sessions, each lasting 50 minutes, 3 times weekly have been tried.
- Behavioral training Program-These include gesture-production exercises.
- With treatment, an improvement in praxis and daily living activities is seen in apraxia patients, based on some studies. The communicative gestures training has led to significant improvement of the gestures which were practiced during the training sessions, with some unpracticed gestures also showing some improvement. However, the sustainability of these positive results is not clear. Although rehabilitative training has been reported to benefit, but, for sustained benefit, training alone is not sufficient.
- Noninvasive brain stimulation- This method had been used widely for many neurological disorders, but there is very limited data for its use in cognitive disorders. However, some studies have shown that this technique has been tried for therapeutic and investigational purpose for this complex neurological disorder and may show some positive results. This technique when used with rehabilitative training, may be useful. Through this technique and different stimulation settings, inhibitory or excitatory influences are exerted on cortical excitability or plasticity. The synergistic approach using this technique prior to rehabilitative training, not only increases the efficacy, but it also increases the sustainability of the improvement seen. Some examples of non-invasive brain stimulation techniques which have been used in some neurological conditions with some improvement in the cognitive function components of the disease can be tried-
Transcranial direct current stimulation (tDCS)-low-level continuous electric current is delivered to influence plasticity and excitabililty of the cortex. In this, anodal tDCS works in excitatory ways, and cathodal tDCS in inhibitory ways.
single-pulse or rTMS- It can be delivered in either low frequency (0.21 Hz) for inhibitory mode, or in high frequency (5 Hz) for excitatory mode.
theta-burst stimulation (TBS)-It is also a magnetic stimulation method like rTMS, but it shows equal efficacy even with shorter stimulation period.
paired associative stimulation (PAS)- This stimulation technique can be used to tackle physiological mechanisms underlying memory using long-term depression (LTD), and long-term potentiation (LTP).
- Transcranial direct current stimulation (tDCS)-low-level continuous electric current is delivered to influence plasticity and excitabililty of the cortex. In this, anodal tDCS works in excitatory ways, and cathodal tDCS in inhibitory ways.
- single-pulse or rTMS- It can be delivered in either low frequency (0.21 Hz) for inhibitory mode, or in high frequency (5 Hz) for excitatory mode.
- theta-burst stimulation (TBS)-It is also a magnetic stimulation method like rTMS, but it shows equal efficacy even with shorter stimulation period.
- paired associative stimulation (PAS)- This stimulation technique can be used to tackle physiological mechanisms underlying memory using long-term depression (LTD), and long-term potentiation (LTP).
- There are no specific recommended therapeutic interventions for the management of Apraxia
- Apraxia is believed to have an adverse impact on the Activity of Daily Living independence. There are limited information and research available regarding various treatments. Various interventions include:
Daily living doings training: this method explains internal and external compensatory approaches that permit a functional mission to be accomplished.
Sensory Stimulation: Including deep pressure stimulation, soft and sharp touch are useful to the patients' limbs.
Chaining (forward or backward): This method is fragmented down into its sections. The task is done with assistance from the therapist separately from the final element through backward chaining, which the patient performs out unassisted. If positive next time, additional steps are presented. Forward chaining is the opposite of backward chaining;
Proprioceptive stimulation: The patient props on and puts his weight through their upper and lower extremities;
Cueing, physical or verbal stimuli: This technique enables each phase of the task to be completed
- Daily living doings training: this method explains internal and external compensatory approaches that permit a functional mission to be accomplished.
- Sensory Stimulation: Including deep pressure stimulation, soft and sharp touch are useful to the patients' limbs.
- Chaining (forward or backward): This method is fragmented down into its sections. The task is done with assistance from the therapist separately from the final element through backward chaining, which the patient performs out unassisted. If positive next time, additional steps are presented. Forward chaining is the opposite of backward chaining;
- Proprioceptive stimulation: The patient props on and puts his weight through their upper and lower extremities;
- Cueing, physical or verbal stimuli: This technique enables each phase of the task to be completed
- Surgical intervention is not recommended for the management of Apraxia.
- There are no established measures for the primary prevention of Apraxia. Some steps can be used which include.
Exercise regularly.
Eat a healthy diet.
Limit how much alcohol you drink.
Quit smoking
Check your blood pressure often.
- Exercise regularly.
- Eat a healthy diet.
- Limit how much alcohol you drink.
- Quit smoking
- Check your blood pressure often.
Effective measures for the secondary prevention of Apraxia include secondary prevention of stroke.
- Aspirin, clopidogrel, extended-release dipyridamole, ticlopidine
- Anticoagulants (apixaban, dabigatran, edoxaban, rivaroxaban, warfarin)
- Blood pressure-lowering medications.
- Diabetes Control
- Low-fat diet
- Cholesterol-lowering medications, Cessation of cigarette smoking, carotid revascularization
- Weight loss and Exercise

# Related Chapters
- Dyspraxia