Autism spectrum disorder is a developmental disability. It results in social, communication, and behavior challenges that can range from mild to severe. Signs of ASD begin in late infancy or early childhood. Sometimes it takes until the child is older to spot them. The signs of ASD continue throughout the life span. Before 2013, many terms described autism disorders. In 2013, the American Psychiatric Association merged all autism disorders into one umbrella diagnosis of ASD. They published the Diagnostic and Statistical Manual of Mental Disorders (DSM-5). Health care providers use DSM-5 to assign diagnoses, including ASD. The term "spectrum" allows for variations in the symptoms and behaviors found among children with ASD.

All the causes of ASD are not yet known. Environmental, genetic, and biological factors may make a person more likely to develop ASD. The number of children diagnosed with ASD is growing. Better efforts to diagnose ASD may relate to the increase in cases. It may also be due to an increase in the causes of ASD that are not yet understood.

People with ASD may have impaired motor (movement) skills. Research shows that those with ASD can have limited coordination and postural control. They also may have to work harder to learn skills through imitation. Planning and completing certain movement skills are difficult for many children with ASD. These delays may make it hard for them to form social skills. As a result, they often do not participate with peers.

Research also shows that intervention programs, including physical therapy, can help children with ASD. These programs help children with ASD learn skills and improve their development. Early diagnosis can help them reach their full potential. Physical therapists are members of teams that provide services to children with ASD and their families. They work with people from early childhood through the school years and into adulthood.

The signs and symptoms of ASD vary widely. ASD is a "spectrum" disorder because the symptoms displayed can be mild to severe. People with mild symptoms are at one end of the spectrum. Those with more severe symptoms are at the other end.

Symptoms begin in early childhood and last throughout a person's lifetime. With intervention, symptoms can improve over time. Some parents notice symptoms of ASD before their child's first birthday. By age two, between 80% to 90% of parents see symptoms that interfere with their child's functions.

The two core signs that indicate a person may have ASD are:

• Challenges in social communication and interaction.
• Tends to restrict and repeat patterns of behavior.

Signs and symptoms related to social communication and interaction may include:

• Avoiding eye contact.
• Preferring to play alone and not engage in creative play.
• Little interest in peers.
• Lack of engagement in social interactions.
• Shunning or resisting physical contact.
• Trouble understanding other people's feelings, body language, and tone of voice.
• A poor sense of personal space boundaries.
• Delayed speech and language skills.
• Lack of pointing or responding to pointing.
• Repeated speech on a preferred topic or repetition of words or phrases.

Signs and symptoms related to restricted, repetitive patterns of behavior may include:

• Self-stimulation through repeated activities (flapping hands/arms, spinning, rocking).
• Being easily upset by minor changes or a need to keep routines.
• Obsessive interests, such as lining up toys or other objects.
• Short attention span, except for preferred topics or activities.
• Aggression, self-injury, or temper tantrums.
• Lack of safety awareness.
• Odd reactions to sound, smell, taste, sight, touch, or movement.

Other traits of ASD related to movement include:

• Delays in walking, jumping, skipping (large movement skills).
• Lagging behind using the hands for things like buttoning a shirt or drawing (small movement skills).
• Trouble copying other people's movements (such as performing actions to songs with peers or jumping over a small object).
• Lack of coordination.
• Poor balance.
• Problems planning and repeating movements.
• Trouble doing movements in a specific order.
• Unstable walking.
• Trouble controlling posture.
• Decreased eye-hand coordination.
• Issues using sensory information (such as touch, sound, and gravity) for movement. Problems may range from slow to exaggerated motor responses. A person with ASD may appear to have a low energy level or may crave movement.
• Toe walking.

If you think your child may have ASD, contact a doctor. A correct diagnosis is the first step toward getting the help your child needs. The doctor may refer your child to a specialist for an in-depth evaluation and diagnosis. Specialists who diagnose ASD (or determine ASD is not present) include:

• Developmental pediatricians.
• Child neurologists.
• Child psychologists.
• Child psychiatrists.

The autism diagnostic and treatment team may consist of:

• Physical therapists.
• Occupational therapists.
• Speech-language pathologists.
• Psychologists.
• Developmental pediatricians.

There is no specific test to diagnose ASD. Health care providers may use assessment tools to aid their diagnosis. These may include the:

• Autism Diagnostic Observation Schedule.
• Second edition (ADOS-2).
• Autism Diagnostic Interview-Revised (ADI-R).

For an ASD diagnosis, a child's behavior and development must meet specific criteria. People diagnosed with ASD have symptoms that make it difficult to function. These symptoms are present from early childhood. Symptoms can go unnoticed until the child is older when social demands increase. Parents may recall symptoms they didn't understand as ASD at that time.

Physical therapists have unique training in child development and motor control. This expertise allows them to assess a child's motor delays and functional performance. Physical therapists work with your child, the family, and your child's school to help them:

• Engage and improve in daily routines at home and school.
• Acquire new movement skills.
• Develop better coordination and a more stable posture.
• Improve play skills, such as throwing and catching a ball with another person.
• Develop motor imitation skills (learn by copying another person's actions).
• Increase fitness and stamina.

A physical therapist will evaluate your child thoroughly. This will include taking a health and developmental history. Your child's physical therapist also will assess:

• Postural strength and control.
• Functional mobility (such as walking and running).
• Body and safety awareness.
• Coordination.
• Play skills.
• Interests and motivators.
• Ability to change between different activities.
• How your child jumps, hops, pedals a tricycle or bicycle, and skips.
• Daily routines in the home, community, and school.

Your physical therapist will work with you to develop goals to help your child participate as fully as possible at home and school. Your physical therapist will then create a plan to meet your child's and your whole family's needs. No "standard" treatment exists for children with ASD. Each child's challenges and goals are different. Your physical therapist will personalize a program to meet the strengths and needs of your child. They will work with you to monitor your child's progress. They also will collect data to ensure their plan is helping your child and adjust the plan as your child makes progress.

Physical Therapy in the Early Years: Birth to Age 3

Early delays in your child's movement skills may predict ASD. Reporting symptoms right away can enable early diagnosis so your child can get the help they need sooner.

Physical therapists work with families and caregivers. Their goal is to increase a child's ability to engage in the daily routines that may challenge them.

Physical therapists work with your child to develop age-appropriate movement skills. They use free and structured play to teach your child and help them practice skills. Physical therapists work on increasing your child's strength and coordination. Their treatment plan can include helping your child walk safely and efficiently or how to use stairs. Your child's physical therapist may prioritize the development of imitation skills. They may work with your child to perform actions to songs like "Head, Shoulders, Knees, and Toes" and indoor and outdoor play skills. Physical therapists guide you and your child on adding structure, routines, and physical boundaries into daily life. They promote positive behaviors and help your child play with their peers.

Physical Therapy in the School Years (Including Preschool): Ages 3 to 18

Physical therapists work with parents and teachers. They increase awareness about children with ASD. They also help school staff understand your child's ability to function in school. Physical therapists use the most effective treatments to minimize your child's challenges. Your child's physical therapist will work with you to help make the school experience a positive one. Physical therapists also recommend changes at home and school to help your child thrive, support learning, and teach movement skills. These may include:

• Using ball chairs to reduce "out-of-seat behaviors."
• Hula hoop, carpet square, or special seat to mark personal space.
• Whole-class movement breaks.
• Strategies to teach skills needed to play social games.

Physical therapists provide direct help when needed to improve a child's ability to handle challenges. For example, they work with your child to help them deal with school bus steps, crowded hallways, the lunchroom, and the playground. Physical therapists also work with school teams to promote skills like self-control, listening, and taking turns. They teach your child methods that promote their ability to:

• Copy the movement activities of other children.
• Develop concepts of direction, body and spatial awareness, and coordination.
• Take part in physical education and fitness activities.

Physical Therapy During Adulthood: Age 18+

Physical therapists work with adults with ASD to promote success in daily life. They recommend community resources to increase movement. Physical therapists also design personalized exercise programs. These exercises will promote physical fitness, body coordination, and recreation skills. Physical therapists help adults improve movement, function, and fitness. These skills help people with ASD get and hold a job. They also help them function at home, enjoy activities, and keep a healthy lifestyle.

All physical therapists have the education and experience to treat people with ASD. However, you may want to consider:

• A physical therapist with experience in treating people with ASD. Some physical therapists focus on pediatrics (treating children).
• A physical therapist who is a board-certified specialist in pediatrics or who completed a residency in pediatric physical therapy. This physical therapist has advanced knowledge, experience, and skills that may apply to ASD.

Find a PT, provided by the American Physical Therapy Association, can help you search for physical therapists near you with these and other credentials.

General tips when you are looking for a physical therapist (or other health care provider):

• Ask family, friends, and other health care providers to recommend a physical therapist.
• Ask about the physical therapist's experience working with children with ASD before you make an appointment.
• Be prepared to describe your child's and family's needs in as much detail as possible on your first visit.