Unit 2: Definition, Causes & Prevention, Types, Educational Implication, and Management of

2.1         Locomotor Disability-Poliomyelitis, Cerebral Palsy/Muscular Dystrophy;

2.2         Visual Impairment-Blindness and Low Vision;

2.3         Hearing Impairment-Deafness and Hard of Hearing;

2.4         Speech and language Disorder;

2.5         Deaf-blindness and multiple disabilities;













2.1 Locomotor Disability-Poliomyelitis, Cerebral Palsy/Muscular Dystrophy;


Strictly speaking Locomotor Disability means problem in moving from one place to another — i.e. disability in legs. But, in general, it is taken as a disability related with bones, joints and muscles. It causes problems in person’s movements (like walking, picking or holding things in hand etc.)

The term Locomotor is derived from the Latin words loco – “from a place” and motivus – “causing motion”. So locomotion means movement from one place to another. And thus locomotor disability hampers movement from one place to another.

A person's inability to execute distinctive activities associated with moving, both personally and objects, from place to place, and such inability resulting from afflictions of musculo-skelatol and, or nervous system, has been defined as the Locomotor Disability Locomotor disability can be classified as: congenital and acquired. The common causes of these two forms of affliction can be classified as: congenital and developmental. Common examples being : cerebral palsy, CTEV, meningocele, meningo myelocele, phocomelias, congenital dislocation of hip. Causes of the acquired disability can be put within the following jackets : Infective and Traumatic. The infective ones are: tuberculosis of spine or other joints, chronic osteomyelitis, septic arthritis, acute poliomyelitis, G.B. syndrome, leprosy, encephalitis, AIDS etc. Traumatic ones are: traffic accidents (air, water, road), domestic accidents, industrial accidents, agricultural accidents, fall from height, bullet injuries, explosions, violence, sports injuries, natural catastrophies like earthquakes, floods etc. Then there can be other causes as well, such as vascular. Common examples are: cerebro vascular disease, peripheral vascular disease, perthe's disease. Neoplastic conditions are yet another cause of locomotor disability. For example, brain tumors like astrocytoma, meningioma, spinal tumors like meningioma, astrocytoma, and osteo sarcoma etc.



Cerebral palsy (commonly referred to as CP) affects normal movement in different parts of the body and has many degrees of severity.

CP causes problems with posture, gait, muscle tone and coordination of movement.

The word “cerebral” refers to the brain’s cerebrum, which is the part of the brain that regulates motor function. “Palsy” describes the paralysis of voluntary movement in certain parts of the body.

Cerebral Palsy is a group of conditions that are characterized by chronic disorders of movement or postures; it is cortical in origin, manifests itself early in life and is not the outcome of a progressive disease.



·       Difficulties with fine motor skills due to jerky reflexes

·       Stiff muscles (hypertonia)

·       Exaggerated reflexes


·       Tremors and shakiness

·       Involuntary reflexes

·       Variations in muscle tone (hypertonia and hypotonia)

·       Slow, writhing movement


·       Lack of coordination

·       Difficulty with balance

·       Trouble with fine motor skills

These developmental movement disorders can be limited to: one side of the body, the legs, the arms, all four limbs or just one limb.



Poliomyelitis, also called polio or infantile paralysis, is a highly infectious viral disease that may attack the central nervous system and is characterized by symptoms that range from a mild nonparalytic infection to total paralysis in a matter of hours.


The reason it is called poliomyelitis is because the prefix polio means 'grey' in ancient Greek, myelo refers to the spinal cord, and itis refers to the inflammation of something. Therefore, when we combine all of these terms together we get the inflammation of the spinal cord's grey matter, or poliomyelitis.

Poliomyelitis or infantile paralysis is a viral infection that affects the nerves of the spinal cord, located inside the spinal bones (vertebrae) at the back of the body. This infection can cause permanent paralysis of muscles. Poliomyelitis mostly affects children up to 15 years of age, but can affect adults too. After the acute phase, the disease is not communicable to others. Since poliomyelitis does not affect the brain, the intellectual ability of children with poliomyelitis remains intact.



A spinal cord injury — damage to any part of the spinal cord or nerves at the end of the spinal canal — often causes permanent changes in strength, sensation and other body functions below the site of the injury.

Medical providers divide the spinal cord into four distinct regions. Knowing the region in which the injury is located is often the key to understanding diagnosis and treatment. The four spinal cord regions are:

·       The cervical spinal cord: This is the topmost portion of the spinal cord, where the brain connects to the spinal cord, and the neck connects to the back. This region consists of eight vertebrae, commonly referred to as C1-C8. All spinal cord numbers are descending, so C1 is the highest vertebra, while C8 is the lowest in this region.

·       The thoracic spinal cord: This section forms the middle of the spinal cord, containing twelve vertebrae numbered T1-T12.

·       The lumbar spinal cord: This is a lower region of the spinal cord, where your spinal cord begins to bend. If you put your hand in your lower back, where your back bends inward, you're feeling your lumbar region. There are five lumbar vertebrae, numbered L1-L5.

·       The sacral spine: This is the lower, triangle-shaped region of the spine, also with five vertebrae. While the lumbar cord bends inward, the vertebrae of the sacral region bend slightly outward. There is no actual spinal cord in this section, it is made up of nerve roots which exit the spine at their respective vertebral levels.

·       The coccygeal region, sometimes known as the coccyx or tail bone, consists of a single vertebra at the very base of the spinal cord.

Types of spinal cord injuries

All spinal cord injuries are divided into two broad categories: incomplete and complete.

·       Incomplete spinal cord injuries: With incomplete injuries, the cord is only partially severed, allowing the injured person to retain some function. In these cases, the degree of function depends on the extent of the injuries.

·       Complete spinal cord injuries: By contrast, complete injuries occur when the spinal cord is fully severed, eliminating function. Though, with treatment and physical therapy, it may be possible to regain some function.

Incomplete spinal cord injuries are increasingly common, thanks in part to better treatment and increased knowledge about how to respond—and how not to respond—to a suspected spinal cord injury. These injuries now account for more than 60% of spinal cord injuries, which means we're making real progress toward better treatment and better outcomes.

Some of the most common types of incomplete or partial spinal cord injuries include:

·       Anterior cord syndrome: This type of injury, to the front of the spinal cord, damages the motor and sensory pathways in the spinal cord. You may retain some sensation, but struggle with movement.

·       Central cord syndrome: This injury is an injury to the center of the cord, and damages nerves that carry signals from the brain to the spinal cord. Loss of fine motor skills, paralysis of the arms, and partial impairment—usually less pronounced—in the legs are common. Some survivors also suffer a loss of bowel or bladder control, or lose the ability to sexually function.

·       Brown-Sequard syndrome: This variety of injury is the product of damage to one side of the spinal cord. The injury may be more pronounced on one side of the body; for instance, movement may be impossible on the right side, but may be fully retained on the left. The degree to which Brown-Sequard patients are injured greatly varies from patient to patient.

Knowing the location of your injury and whether or not the injury is complete can help you begin researching your prognosis and asking your doctor intelligent questions. Doctors assign different labels to spinal cord injuries depending upon the nature of those injuries.


 Spina bifida literally means ‘split spine’

A fault in the development of the spinal cord and surrounding bones (vertebrae) leaves a gap or split in the spine. The spinal cord has not formed properly, and may also be damaged. To help understand what it is, it is useful to explain the composition of the nervous system.


The three main types of spina bifida always present at birth are:

Spina Bifida Cystica (cyst-like)

The visible signs are a sac or cyst, rather like a large blister on the back, covered by a thin layer of skin. There are two forms:

1)     Myelomeningocele (meningomyelocele)

Myelomeningocele is the most serious and more common of the two forms of cystic spina bifida. Here the cyst not only contains tissue and cerebro-spinal fluid but also nerves and part of the spinal cord. The spinal cord is damaged or not properly developed. As a result, there is always some paralysis and loss of sensation below the damaged region.

The amount of disability depends very much on where the spina bifida is, and the amount of affected nerve tissue involved. Bladder and bowel problems occur in most people with myelomeningocele, as the nerves come from the bottom of the spinal cord, so are always below the lesion. It is also necessary to have intact nerve pathways to the brain for complete control and sensation.

The outer part of the vertebrae is split. The spinal cord and meninges are damaged and pushed out through the opening. Hydrocephalus is usually associated with this form.

2)     Meningocele

In this form, the sac contains meninges (tissues which cover the brain and spinal cord) and cerebro-spinal fluid, which bathes the central nervous system. Development of the spinal cord may be affected, but impairment is usually less severe than myelomeningocele. Meningocele is the least common form of spina bifida.

The outer part of the vertebrae is split. The spinal cord is normal. The meninges are damaged and pushed out through the opening.

3)Spina Bifida Occulta (hidden form)

This is a mild form of spina bifida which is very common. Estimates vary but between 5% and 10% of people may have spina bifida occulta. It must be emphasised that, for the vast majority of those affected, having spina bifida occulta is of no consequence whatsoever. Often people only become aware that they have spina bifida occulta after having a back x-ray for an unrelated problem.

The outer part of the vertebrae is not completely joined. The spinal cord and its covering (the meninges) are undamaged Encephalocele.

·      Encephalocele

This is a sac which is formed when the bones of the skull fail to develop. It may contain only cerebro-spinal fluid or part of the brain may also be present in the sac, resulting in brain damage.

·      Anencephaly

This is where the brain does not develop properly or is absent, and the baby is either still born or dies shortly after birth.

·      Hydrocephalus Most babies born with myelomeningocele also have hydrocephalus (from the Greek hydro, meaning water, and cephalie meaning brain). This is an accumulation of cerebro-spinal fluid which arises from an imbalance in the production and drainage of that fluid.


¡  Muscular Dystrophy (MD) is a group of inherited diseases in which the voluntary muscles progressively weaken overtime.

¡  Heart and other organs can also be affected.

¡  9 major types:

§  Duchenne, Myotonic, Becker, Limb-girdle, Facioscapulohumeral, Congenital, Oculopharyngeal, Distal, and Emery-Dreifuss

§  Can occur at any age

§  Most common in young males.

§  Type is based on what age the individual is when muscular dystrophy appears

§  Also depends on how severe the disease is, which muscles it affects, rate of progression, and the way it appears.

§  Some types of muscular dystrophy only affect males.

§  Some individuals with this disease experience mild symptoms, while others suffer from severe muscle weakness, dying at an early age.


¡  Multiple sclerosis (MS) is a potentially disabling disease of the brain and spinal cord (central nervous system).

¡  In MS, the immune system attacks the protective sheath (myelin) that covers nerve fibers and causes communication problems between your brain and the rest of your body. Eventually, the disease can cause the nerves themselves to deteriorate or become permanently damaged.

¡  Signs and symptoms of MS vary widely and depend on the amount of nerve damage and which nerves are affected. Some people with severe MS may lose the ability to walk independently or at all, while others may experience long periods of remission without any new symptoms.

¡  There's no cure for multiple sclerosis. However, treatments can help speed recovery from attacks, modify the course of the disease and manage symptoms.

¡  The cause of multiple sclerosis is unknown. It's considered an autoimmune disease in which the body's immune system attacks its own tissues. In the case of MS, this immune system malfunction destroys myelin (the fatty substance that coats and protects nerve fibers in the brain and spinal cord).

¡  Myelin can be compared to the insulation coating on electrical wires. When the protective myelin is damaged and nerve fiber is exposed, the messages that travel along that nerve may be slowed or blocked. The nerve may also become damaged itself. It isn't clear why MS develops in some people and not others. A combination of genetics and environmental factors appears to be responsible.


2.2     Visual Impairment-Blindness and Low Vision;


How We See: The eye functions like a camera. Vision is a complex function. The act of seeing requires light to see by and the brain to interpret what is seen. The light rays reflected from an object in a person’s field of vision fall on the eyes.

The rays pass through the cornea, aqueous humour, and through pupil which dilates or contracts to control light in accordance to the brightness of the object. The rays then pass through crystal lineless and the rays of light are focussed on the retina. The process of focusing is called accommodation. The cornea and the lens combine to bend the light rays as they pass through. The rays pass through the vitreous body and penetrate on retina, where they set up a photo-chemical response in the outermost layers, stimulating the rods & cones.

The impulse is picked by retinal nerve fibres and passes along the optic nerve to the brain where an upside down image is formed. Based on experience, the inverted image is psychologically transposed.

Definition of visual impairment as adopted in the persons with Disabilities (Equal opportunities, Protection of Right & Full Participation) Act 1995 as well as National Programme for control of Blindness (NPCB).

Blindness: refers to a condition where a person suffers from any of the following conditions, namely:

1.     Total absence of sight; or

2.      Visual acuity not exceeding 6/60 or 20/200 (snellen) in the better eye even with the correction lenses, or

3.     Limitation of the field of vision subtending an angle of 20 degree or worse

For deciding blindness visual acuity and / or field of vision are considered.

Low vision: As per PWD Act, 1995 also recognises low vision as a category of disability and defines it as follows:- “Person with low vision,” means a person with impairment of visual functioning even after treatment or standard refractive correction but who uses or is potentially capable of using vision for the planning or execution of a task with appropriate assistive device.

For teachers this definition is of no use as it does not give the range of visual acuity as well as field of vision. Practitioners therefore follow the WHO working definition of low vision- “A person with low vision is one who has impairment of visual functioning even after treatment and/or standard refractive correction, and has a visual acuity of less than 6/18 to light perception or a visual field of less than 10 degrees.”

The World Health Organization uses the following classifications of visual impairment. When the vision in the better eye with BEST POSSIBLE glasses correction is:

·       20/30 to 20/60 is considered mild vision loss, or near-normal vision

·       20/70 to 20/160 is considered moderate visual impairment, or moderate low vision

·       20/200 to 20/400 is considered severe visual impairment, or severe low vision. In the United states, a person with 20/200 in the BETTER eye is considered legally blind.

·       20/500 to 20/1,000 is considered profound visual impairment, or profound low vision

·       less than 20/1,000 is considered near-total visual impairment, or near total blindness

·       no light perception is considered total visual impairment, or total blindness.

The International Classification of Diseases 11 (2018) classifies vision impairment into two groups, distance and near presenting vision impairment.

Distance vision impairment:

·       Mild – presenting visual acuity worse than 6/12

·       Moderate – presenting visual acuity worse than 6/18

·       Severe – presenting visual acuity worse than 6/60

·       Blindness – presenting visual acuity worse than 3/60

Near vision impairment:

·       Presenting near visual acuity worse than N6 or M.08 with existing correction.


2.3     Hearing Impairment-Deafness and Hard of Hearing;



The process of hearing begins with the occurrence of a sound. Sound is initiated when an event moves and causes a motion or vibration in air. When this air movement stimulates the ear, a sound is heard and the human ear can hear from 20 Hz to 20,000 Hz. 

In the human ear, a sound wave is transmitted through four separate mediums along the auditory system before a sound is perceived: in the outer ear—air, in the middle ear— mechanical, in the inner ear liquid and to the brain—neural.

Sound Transmission through the Outer Ear - Air transmitted sound waves are directed toward the delicate hearing mechanisms with the help of the outer ear, first by the pinna, which gently funnels sound waves into the ear canal, then by the ear canal.

Sound Transmission through the Middle Ear- When air movement strikes the tympanic membrane, the tympanic membrane or eardrum moves. At this point, the energy generated through a sound wave is transferred from a medium of air to that which is solid in the middle ear. The ossicular chain of the middle ear connects to the eardrum via the malleus, so that any motion of the eardrum sets the three little bones of the ossicular chain into motion.

Sound Transmission through the Inner Ear- The ossicular chain transfers energy from a solid medium to the fluid medium of the inner ear via the stapes. The stapes is attached to the oval window. Movement of the oval window creates motion in the cochlear fluid and along the Basilar membrane. Motion along the basilar membrane excites frequency specific areas of the Organ of Corti, which in turn stimulates a series of nerve endings.

Sound Transmission to the Brain- With the initiation of the nerve impulses, another change in medium occurs: from fluid to neural. Nerve impulses are relayed through the VIII C.N., through various nuclei along the auditory pathway to areas to the brain. It is the brain that interprets the neural impulses and creates a thought, picture, or other recognized symbol.


        A person who is not able to hear as well as someone with normal hearing – hearing thresholds of 25dB or better in both ears – is said to have hearing loss.

        ‘Hard of hearing’ refers to people with hearing loss ranging from mild to severe.

        ‘Deaf’ people mostly have profound hearing loss, which implies very little or no hearing

Person with disability act- (PWD, 1995)

·      Definition of disability in pwd act includes hearing impairment

Hearing impairment means loss of 60 decibel or more in the better ear in speech conversation frequencies.

·      Chapter 5 education have point for restructuring the curriculum for benefit of students with hearing impairment , to facilitate them to take only one language as part of their curriculum.

Idea- individual with disability education act, 2004

·      Defines hearing impairment as impairment in hearing, whether permanent or fluctuating that adversely affects a chill’s educational performance but is not included under the definition of deafness.

World health organization (WHO) -

·      Defines – A person who is not able to hear as well as someone with normal hearing – hearing threshold of 25db or better in both ears is said to have hearing loss.


According to place of impairment

        conductive hearing loss – hearing loss due to the interference in the transmission of sound to and through the sense organ (outer or middle ear)

       Sensory-neural hearing loss – due to the abnormality of the inner ear or the auditory nerve, or both

        mixed hearing loss - combination of both; sometimes called a flat loss

According to degree of hearing loss –

        Loss Slight 27-40 dB

       Mild 41-55 dB

       Moderate 56-70 dB

       Severe 71-90 dB

       Profound 91 dB or more

According to the age at onset of deafness

·      Congenitally deaf – born deaf

·      Adventitiously deaf – born with normal hearing and became deaf through accident/illness

According to language development-

• Prelingually deaf – born deaf oer lost hearing before speech and language were developed

 • Post lingually deaf- lost hearing after development of spontaneous speech and language.

Ø National institute for the hearing handicapped-

Various types of impairments


Type of


DB level

Word recognition score

% of



Mild hearing


26- 40


80-100 % in better


Less than 40%

     II.            a

Moderate hearing




50-80 % in better




Severe hearing




40-50 % in better




a)profound hearing




Less than 40% in better ear



b) total loss

91 and


Very poor




2.4     Speech and language Disorder;

Speech and language disorders refer to problems in communication and related areas such as oral motor function. These delays and disorders range from simple sound substitutions to the inability to understand or use language or use the oral-motor mechanism for functional speech and feeding. Some causes of speech and language disorders include hearing loss, neurological disorders, brain injury, mental retardation, drug abuse, physical impairments such as cleft lip or palate, and vocal abuse or misuse. Frequently, however, the cause is unknown.


A child's communication is considered delayed when the child is noticeably behind his or her peers in the acquisition of speech and/or language skills. Sometimes a child will have greater receptive (understanding) than expressive (speaking) language skills, but this is not always the case.

Speech disorders refer to difficulties producing speech sounds or problems with voice quality. They might be characterized by an interruption in the flow or rhythm of speech, such as stuttering, which is called dysfluency. Speech disorders may be problems with the way sounds are formed, called articulation or phonological disorders, or they may be difficulties with the pitch, volume or quality of the voice. There may be a combination of several problems. People with speech disorders have trouble using some speech sounds, which can also be a symptom of a delay. They may say "see" when they mean "ski" or they may have trouble using other sounds like "l" or "r". Listeners may have trouble understanding what someone with a speech disorder is trying to say. People with voice disorders may have trouble with the way their voices sound.

For children with speech disorders, it can be tough forming the sounds that make up speech or putting sentences together. Signs of a speech disorder include:

·       Trouble with p, b, m, h, and w sounds at 1 to 2 years of age

·       Problems with k, g, f, t, d, and n sounds between the ages of 2 and 3

·       When people who know the child well find it hard to understand them

The causes of most speech disorders are unknown.

There are three major types:

Articulation: It’s hard for your child to pronounce words. They may drop sounds or use the wrong sounds and say things like “wabbit” instead of “rabbit.” Letters such as p, b, and m are easier to learn. Most kids can master those sounds by age 2. But r, l, and th sounds take longer to get right.

Fluency: Your child may have problems with how their words and sentences flow. Stuttering is a fluency disorder. That’s when your child repeats words, parts of words, or uses odd pauses. It’s common as kids approach 3 years of age. That’s when a child thinks faster than they can speak. If it lasts longer than 6 months, or if your child is more than 3.5 years old, get help.

Voice: If your child speaks too loudly, too softly, or is often hoarse, they may have a voice disorder. This can happen if your child speaks loudly and with too much force. Another cause is small growths on the vocal cords called nodules or polyps. They’re also due to too much voice stress.


A language disorder is an impairment in the ability to understand and/or use words in context, both verbally and nonverbally. Some characteristics of language disorders include improper use of words and their meanings, inability to express ideas, inappropriate grammatical patterns, reduced vocabulary and inability to follow directions. One or a combination of these characteristics may occur in children who are affected by language learning disabilities or developmental language delay. Children may hear or see a word but not be able to understand its meaning. They may have trouble getting others to understand what they are trying to communicate.

Your child may have this disorder if they:

·       Don’t babble by 7 months

·       Only speak a few words by 17 months

·       Can’t put two words together by 2 years

·       Have problems when they play and talk with other kids from the ages of 2 to 3

There are two major types of language disorders. It’s possible for a child to have both.

Receptive: This is when your child finds it hard to understand speech. They may find it hard to:

·       Follow directions

·       Answer questions

·       Point to objects when asked

Expressive: If your child has trouble finding the right words to express themselves, they may have this type of language disorder. Kids with an expressive disorder may find it tough to:

·       Ask questions

·       String words into sentences

·       Start and continue a conversation

It’s not always possible to trace the cause of language disorders. Physical causes of this type of disorder can include head injuries, illness, or ear infections. These are sometimes called acquired language disorders.

There are many types of disorders within various categories, and each person’s condition may be different. Following are some of the most common speech disorders that speech therapists treat.

1. Childhood Apraxia of Speech

With childhood apraxia of speech, a child has trouble making accurate movements when speaking. It occurs because the brain has difficulty coordinating the movements.

2. Orofacial Myofunctional Disorders

Children, teenagers, and adults may suffer from these abnormal movement patterns of the face and mouth. They occur due to an abnormal growth and development of facial muscles and bones, the cause of which is unclear. Individuals with orofacial myofunctional disorders may have trouble eating, talking, breathing through the nose, swallowing, or drinking.

3. Speech Sound Disorders/Articulation Disorders

Especially common in young children, articulation disorders are based on the inability to form certain sounds. Instead, certain words and sounds may be distorted, such as making the “th” sound in place of an “s” sound.

4. Stuttering and Other Fluency Disorders

Stuttering can come in a number of forms, including “blocks” characterized by long pauses, “prolongations” characterized by stretching out a sound, and “repetitions” characterized by repeating a particular sound in a word. Stuttering is not always a constant, and it can be exacerbated by nervousness or excitement.

Individuals who stutter may feel tenseness in their bodies and may even avoid situations or words that may trigger their stuttering. Secondary physical behaviors may include excessive eye blinking or jaw tightening.

5. Receptive Disorders

Receptive disorders are characterized by trouble understanding and processing what others say, causing trouble following directions or a limited vocabulary. Disorders such as autism can lead to receptive disorders.

6. Autism-Related Speech Disorders

Communication concerns are one aspect of autism spectrum disorder, which involves challenges with social skills and repetitive behaviors. An individual with autism may have difficulty understanding and using words, learning to read or write, or having conversations.

He or she may also be hard to understand, use a robotic voice, and speak very little or not at all.

7. Resonance Disorders

Resonance disorders occur due to a blockage or obstruction of airflow in the nose, mouth, or throat, which may affect the vibrations that determine voice quality. Cleft palate and swollen tonsils are two causes of resonance disorders.

8. Selective Mutism

Most often seen in children and teens, selective mutism is an anxiety disorder characterized by a child’s inability to speak and communicate effectively in select social settings. Teenagers who experience selective mutism may have more pronounced social phobias.

9. Brain Injury-Related Speech Disorders/Dysarthria

Dysarthria occurs when the muscles in the lips, mouth, tongue, or jaws are too weak to properly form words, usually due to brain damage. These include traumatic brain injury and right hemisphere brain injury.

10. Attention Deficit/Hyperactivity Disorder Symptoms

ADHD makes it hard for individuals to pay attention and control their own behavior, leading to various problems with communication. Although not everyone with ADD has the hyperactivity aspect of the disorder, those who do may have trouble sitting still as well. A speech and language pathologist can help improve the communication aspect of ADHD.


2.5  Deaf-blindness and multiple disabilities;


Deafblindness is the combination of significant auditory and visual impairments in a person. These dual sensory losses vary in severity from person to person and do not necessarily lead to total deafness and/or total blindness. It is entirely possible that the person will retain some useful vision and hearing. However, in combination, these impairments of the distant senses causes serious developmental delays in the child, affecting cognitive development, social development, acquisition of communication and language skills, orientation and mobility. A combination of visual and hearing impairment causes such severe developmental, communication and learning needs that the person cannot be educated in special education programs meant for the hearing impaired, for the visually impaired or for severe disabilities. Supplementary assistance would be required to address their unique educational needs consequential to the concurrent impairments of vision and hearing. Deafblindness leads to a severe disabling condition caused by combined losses in hearing and vision. A deafblind child cannot be thought of as blind and also deaf, nor as deaf and also blind. Various terms have been used in the past to refer to this heterogeneous group of population. Earlier, the term ‘deaf blind’ or ‘deaf-blind’ was used. However, keeping with the belief that impairments in both hearing and vision have, not an additive, but a multiplicative effect on the affected individual, the term ‘deafblind’ is now used. Deafblindness is a unique disability; it has its own concepts and terminology, its own methods of assessment and means of education, and its own modes of communication, which distinguishes “deafblindness” from deafness and blindness. Deafblindness is not a medical concept, surprisingly; medical literature makes few references to deafblindness. It is a developmental concept which helps us to understand the nature and the extent of a disability consequent to deafblindness. Because 95 percent of what we learn comes through our eyes and ears, deafblindness leads to difficulties in communication, mobility, and in accessing information.

Deafblind people fall into four groups:

1. Those who are born deaf and blind, which can happen if the mother, inter alia, contacted Rubella (German Measles) during pregnancy.

2. Those who were born deaf and then lost their sight. This is often caused by the Usher Syndrome – deafness followed by a decrease in sight because of retinitis pigmentosa (tunnel vision).

3. Those who were born blind and then lost their hearing.

4. The adventitious deafblind, as a result of old age, or through an illness or accident later in life.

Definition of Deafblindness

“Deafblindness is the condition of having little or no useful sight and hearing. As with the word ‘deaf ’, it can be capitalized to indicate that it is a culture; some prefer the spelling ‘Deafblind’. The most well known deafblind person is the author, activist and lecturer Helen Keller.”

Deaf-blind people have an experience quite distinct from people who are only deaf or blind and not both.

Federal Definition of Deafblindness – USA

“Concomitant hearing and visual impairments, the combination that creates such severe communication and other developmental and educational needs that they cannot be accommodated in special education in programs solely for children with deafness or children with blindness.” FR Dept. of Education

“Deafblindness” is a condition presenting other difficulties than those caused by deafness and blindness. It is an “umbrella” term, which can include both children and adults who are:

• Blind and profoundly deaf.

• Blind and severely or partially hearing impaired.

• Partially sighted and profoundly deaf.

• Partially sighted and severely or partially hearing impaired.

“The term, ‘children with deafblindness’, means children and youth having auditory and visual impairments, the combination of which creates such severe communication and other developmental and learning needs that they cannot be appropriately educated without special education and related services, beyond those that would be provided solely for children with hearing impairments, visual impairments, or severe disabilities to address their educational needs due to these concurrent disabilities.”


Children who have a combination of severe disabilities are called “Multiply Disabled”. Caring for multiply and severely disabled children is never easy and they need an enormous amount of time, patience and love.

Realising the need for promotion of services for children with multiple disabilities, an autonomous organization of the Ministry of Social Justice and Empowerment, Government of India, was set up under the “National Trust for the Welfare of Persons with Autism, Cerebral Palsy, Mental Retardation and Multiple Disabilities” Act (Act 44 of 1999).The National Trust was set up to find an answer to the worries of parents of such children.

Definition of Multiple Disabilities

Multiple disabilities - “concomitant impairments (such as mental retardation-blindness, mental retardation-orthopedic impairment, etc.) the combination which causes such severe educational needs that they cannot be accommodated in programs solely for one disability. (IDEA)

According to the act “Multiple Disabilities” means a combination of two or more disabilities as defined in clause (i) of section 2 of the Persons with Disabilities (Equal Opportunities, Protection of Rights and Full Participation) Act, 1995 (1 of 1996). Disabilities under the National Trust Act are in fact Developmental Disabilities caused due to insult to the brain and damage to the central nervous system. These disabilities are Autism, Cerebral Palsy, Mental Retardation and Multiple Disabilities. These are neither diseases nor contagious nor progressive. They cannot be cured by drugs or surgery. But early detection and training improve outcome. This is done using the services of Physio-Occupational and Speech Therapists, Community Based Rehabilitation Workers and Special Educators.

The combination of disabilities and degree of severity is different in each child. The time at which the disability occurs in the child, what is known as the ‘age of onset’, may also range from birth to a few days after birth, from early childhood till late teens. Sometimes children are born with one disability but acquire the second or third disabling conditions during childhood. The characteristics and the needs of the children depend on the nature of combination of the disabilities, the age of onset and the opportunities that have been available to a child in his environment.     

Multiple Disability refers to: a combination of two or more disabling conditions that have a combined effect on the child’s communication, mobility and performance of day-to-day tasks.

We can say that just as every child is different, similarly every child with MD is different. However there are some things that this group of children have in common.

·      It affects the all-round development of the child

·      Communication with the world around is most severely affected

·      Opportunities to interact with the environment becomes very limited

·      Ability to move around in the environment is restricted

·      Need regular help in simple day-to-day activities such as wearing a shirt, opening a door,

·      Finding a chair to sit down and so on.

·      A highly structured educational / rehabilitation programme helps in their training.


Some examples of multiple disabilities are:

·       Deafblind (Visual Impairment + Hearing Impairment)

·       Visual Impairment + Hearing Impairment + Mental Retardation

·       Visual Impairment + Mental Retardation

·       Cerebral Palsy + Mental Retardation/ Hearing/ Speech/ Visual problems

Given the numerous disability category combinations possible, the designation multiple disabilities encompasses a broad range of traits. However, the National Dissemination Center for Children with Disabilities (usually referred to as NICHCY) lists several common characteristics, including hampered speech and communication skills, challenges with mobility and a need for assistance in performing everyday activities. It’s also worth noting that medical conditions such as seizures and “water on the brain” (hydrocephalus) can accompany multiple disabilities.