Introduction

What is apraxia?

Apraxia is a brain and nervous system disorder which makes a person unable to perform familiar movements that have been learned previously or can be easily imitated by observing other individuals or following their directions.¹,² People suffering from apraxia struggle in performing daily tasks like tying shoelaces or buttoning their shirts. They are unable to follow instructions or commands even though they are willing to perform the tasks. Sometimes, unbeknownst to patients, they are unable to perform the skills and activities they were previously able to do. Apraxia can result from a head injury or disease affecting the brain such as stroke (life threatening condition in which blood supply to a part of the brain is cut-off), dementia (group of diseases that affect memory, thinking, reasoning), or tumors (group of abnormal cells that form lumps or growths). Diagnosis of apraxia involves a comprehensive neurological examination to exclude other potential causes. The treatment plan involves the management of the underlying disorder and the implementation of supportive measures. Early diagnosis and treatment can help patients in the management of daily activities.

Types of apraxia

Apraxia can be further classified into subtypes such as ideomotor, conceptual, and constructional, ideational, limb-kinetic, buccofacial, oculomotor, and verbal apraxia.

• Ideomotor apraxia: Most common type of limb apraxia, which causes inability to perform common motor functions, such as waving goodbye or demonstrating how to use a toothbrush³
• Conceptual apraxia: Impaired ability to use tools such as a screwdriver correctly
• Constructional apraxia: Unable to draw, construct, or copy objects despite understanding them and being physically able to do it
• Ideational apraxia: Inability to understand the purpose of a learned complex task, making it hard to plan or execute the steps in the correct order. E.g., putting on a shoe before putting on the socks⁴
• Limb-kinetic apraxia: Struggle to use a finger, arm, or leg to make precise and coordinated movements. People with limb-kinetic apraxia are unable to repeat the same movement that has been carried out by them in the past
• Buccofacial apraxia: Struggle to make facial and lip movements on command
• Oculomotor apraxia: Difficulty in making eye movements on command
• Verbal apraxia: People with verbal or oral apraxia struggle to produce sounds or understand speech rhythms
• Apraxia of speech: This is further classified into two types: 
  • Acquired apraxia of speech (other names: verbal or oral apraxia): Commonly found in adults but can affect people of all age groups. It leads to a loss of speech-making abilities you once had. This disorder, when diagnosed in adults, is called adult apraxia of speech
  • Childhood apraxia of speech: This is a congenital motor speech disorder (difficulty moving the muscles needed for speech production due to weakness or reduced coordination). It happens because the brain struggles to send the right signal to the mouth to move the lips, jaw, and tongue, which leads to difficulty in forming sounds and words. Children with childhood apraxia can understand speech better than they can express themselves with spoken words. With the right treatment, children with childhood apraxia can get better, even though they might not recover completely

How is apraxia diagnosed?

Signs and symptoms of apraxia

Patients with apraxia struggle to perform day-to-day activities even after having the understanding and physical ability to do so. They are unable to follow instructions, fail to speak the correct word, and perform the correct action that is actually intended. Patients struggle to coordinate the correct sequence of muscle movements. Signs and symptoms of apraxia vary depending on the part of the brain that is involved. 

Common symptoms depending on the type of apraxia may include the following issues:

• Facial movements while coughing
• Precise finger, arm, or leg movements 
• Using specific tools for specific tasks
• Eye movements such as winking
• Carrying out complicated tasks such as brushing teeth or tying shoes
• Imitating movements with your head, arms, or legs
• Taking small steps
• Copying simple drawings

Symptoms of speech apraxia include:

• Difficulty in putting words together in the correct order, resulting in distorted, repeated, or left out speech sounds or words
• Struggling to pronounce the right word
• It may be difficult to use longer words all the time or occasionally
• Struggling to use everyday phrases (such as  “how are you?”) or sayings without a problem

The following are the earliest signs of apraxia of speech in children:

• Limited babbling in babies
• Reduced variety of sounds 
• Omission of sounds within words, especially at the beginning of a word
• Unable to say a word correctly sometimes
• Struggling to speak an already learned word 
• Preferring nonverbal forms of communication, such as nodding or pointing, over verbal communication

Childhood apraxia of speech is often accompanied by other language and memory deficits, such as difficulty in chewing and swallowing.

Diagnosis  

Conditions like stroke or traumatic injury to the brain may lead to apraxia. Apraxia might be idiopathic in some cases. To diagnose apraxia, doctors use thorough assessment methods, such as detailed medical history, physical examination, along with other tests like neuropsychological testing (tests to measure how well your brain works), hearing and listening abilities test to identify the signs and symptoms, types, and underlying etiology of apraxia. The doctor will ask the patient to perform regular day-to-day tasks like using a toothbrush, scissors, or other common instruments. A physical exam may be done to detect any problems with the joint and muscles. The doctor might perform some brain function tests to check a patient's problem-solving skills, memory, language, attention, and processing skills. These tests may also help the doctors in ruling out other similar conditions like aphasia (a brain disorder where a person has trouble communicating or understanding other people speaking) and dyspraxia (a neurological condition that affects movement and coordination). The doctor might check with family members to know if the patient is able to perform daily activities.

If the cause of apraxia is unknown, the doctor may suggest some additional examinations, such as:

• Radiological exams like computed tomography (CT) scan to detect tumors, strokes, multiple sclerosis, or other brain injury
• Laboratory exam, like a spinal tap, to check for inflammation or infection associated with the brain,
• Imaging tests like magnetic resonance imaging (MRI) and positron emission tomography (PET) to identify brain lesions (any area of damaged tissue)
• An electroencephalogram (EEG) may be recommended to rule out epilepsy

In case of suspicion of apraxia of speech, standardized language and intellectual tests may be recommended. Patients might be tested for other learning disabilities as well.

Treatment

Currently, a widespread treatment strategy for apraxia does not exist. Treatment focuses on curing the underlying cause of apraxia and managing the signs and symptoms of apraxia. Primary treatment modality for management of apraxia focuses on rehabilitation using physical, speech, or occupational therapy. These therapies can help in improving patients' quality of life.  Apraxia causes significant impairment of a patient's functional capacity. Post-stroke patients with apraxia might need caregiver support.⁵

Studies suggest that creating task-specific therapies with generalizable benefits is a challenge.⁶ 

For cases of apraxia caused by lesions, rehabilitation is promptly initiated.⁷,⁸ In some cases, treatment with new technologies like transcranial magnetic stimulation has shown promising results.9 In case of childhood apraxia of speech, speech-language therapy is the recommended mode of treatment. In cases that do not respond to speech-language therapy, regular consultation with a speech-language pathologist might be recommended. Specialized treatment plans focusing particularly on the needs of the child show the best results.

The aim of speech therapy is to improve speech coordination. Speech therapy activities include:

• Repeatedly practicing the formation and pronunciation of  sounds and words
• Practicing stringing together sounds to make speech
• Working with rhythms or melodies
• Encouraging the child to watch in a mirror while trying to form words or to touch their face while talking. These multisensory approaches engage different senses to enhance learning and improve awareness of mouth movements during speech production

If childhood apraxia of speech is severe, teaching kids alternative ways to communicate, such as writing, drawing, and painting, might be helpful. Parents can also use electronic devices such as computers, which can produce words and sentences to assist in teaching. Therapists also believe that teaching sign language to children may help them communicate. However, studies determining the effectiveness of treatment for childhood apraxia of speech are rare.

Summary 

Often overlooked, apraxia is one of the most important neurology syndromes. It’s the inability of affected individuals to perform skilled movements, whether previously learned or that can be easily imitated by observing or following instructions given by another individual. It may be caused by a head injury or a disease affecting the brain. It is common in older age groups, as they have a higher susceptibility of experiencing stroke and dementia. Apraxia can be classified based on the patient's ability to perform specific tasks or take general actions. Sadly,  the subtypes of apraxia have not been consistently defined in the literature. Diagnosis involves a thorough physical examination by the doctor, detailed medical history, and various tests to check for sensory dysfunction, comprehension deficits, or incoordination as potential causes of apraxia.  There is no specific treatment commonly followed for apraxia worldwide. The management of apraxia focuses on addressing the underlying causes through physical, occupational, or other specific therapies, alongside counseling. The prognosis of apraxia depends on its type and the effect it has on the patient's daily activities. If a person has apraxia due to a stroke or another neurological disorder, symptomatic treatment for the underlying condition might help. Long-term assisted nursing care may be needed in some individuals with apraxia. Limited research on treatment plans for apraxia hinders the ability to draw definitive conclusions about their effectiveness.