Lesser Known Disorders
Each issue of this series contains at least three lesser known disorders. Some of these disorders may contain subtypes which will also be presented. You will also notice that each disorder has a code. These codes represent the coding system for all disabilities and disorders listed in the Educator’s Diagnostic Manual(EDM) Wiley Publications.
Disorders in this issue:
OI 9.00 Spina Bifida
Disability Category- Orthopedic Impairment
Definition
Spina bifida (SB) is a neural tube defect (a disorder involving incomplete development of the brain, spinal cord, and/or their protective coverings) caused by the failure of the fetus’s spine to close properly during the first month of pregnancy (Spina Bifida Association, 2006; National Institute of Neurological disorders and Stroke, 2005g; U.S. National Library of Medicine, 2004k). It is the most frequently occurring permanently disabling birth defect (Hardman, Drew, & Egan, 2005).
Diagnostic Symptoms
Infants born with Spina Bifida sometimes have an open lesion on their spine where significant damage to the nerves and spinal cord has occurred. Although the spinal opening can be surgically repaired shortly after birth, the nerve damage is permanent, resulting in varying degrees of paralysis of the lower limbs. Even when there is no lesion present there may be improperly formed or missing vertebrae and accompanying nerve damage. In addition to physical and mobility difficulties, most individuals have some form of learning disability (National Institute of Neurological disorders and Stroke, 2005g).
Further Key Points
An estimated 70,000 people in the United States are currently living with spina bifida. There are 60 million women at risk of having a baby born at risk for spina bifida and about 3,000 pregnancies are affected by these birth defects each year (Spina Bifida Association, 2006).
Types of Spina Bifida
OI 9.01-Meningocele
Definition
Meningocele occurs when the spinal cord develops normally but the meninges protrude from a spinal opening (National Institute of Neurological Disorders and Stroke, 2005). Meningocele is the name used when just the meninges—no nerves—push through the opening in the vertebrae. The meninges form a fluid-filled sac that is usually covered with skin (Nemours Foundation, 2005g).
Explanation
With this disorder the spinal cord is normal and a person with a meningocele usually has no mobility impairments (Turnbull, Turnbull, and Wehmeyer, 2006). A person with meningocele will need surgery to prevent any nerve damage later (Nemours Foundation, 2005c).
OI 9.02-Myelomeningocele
Definition
Myelomeningocele is one of the most common birth defects of the central nervous system. It is a neural tube defect in which the bones of the spine do not completely form, and the spinal canal is incomplete. This allows the spinal cord and meninges (the membranes covering the spinal cord) to protrude out of the child’s back (U.S. National Library of Medicine, 2004h).
Explanation
The symptoms of this disorder include:
- visible sac-like protrusion on the mid to lower back of a newborn
- not translucent when a light is shone from behind the sac
- weakness of the hips, legs, or feet of a newborn
This is the most serious form of spina bifida and results in varying degrees of leg weakness, inability to control bowels or bladder, and a variety of physical problems such as dislocated hips or club feet (Turnbull, Turnbull, & Wehmeyer, 2006)
OI 9.03-Spina Bifida Occulta
Definition
Occulta is the mildest and most common form in which one or more vertebrae are malformed. The name “occulta,” which means “hidden,” indicates that the malformation, or opening in the spine, is covered by a layer of skin. This form of spina bifida rarely causes disability or symptoms (National Institute of Neurological Disorders and Stroke, 2005g).
Explanation
Because the spinal nerves aren’t involved, most children with this form of spina bifida have no signs or symptoms and experience no neurologic problems. An abnormal tuft of hair, a collection of fat, a small dimple or a birthmark may be seen on the newborn’s skin above the spinal defect and may be the only indication of the condition. In fact, most people who have spina bifida occulta don’t even know it, unless the condition is discovered during an X-ray for unrelated reasons (Mayo Clinic, 2003).
HI 1.02-Pure word deafness
Disability Category – Hearing Impairment
Definition
Pure word deafness is a specific deficit of perception of spoken language while other auditory perception is intact. The individual’ speech is intact but some garbled language may be present at the onset of illness. Writing is normal while reading may be impaired (National Academy of Neuropsychology, 2000). In pure word deafness, comprehension and repetition of speech are impaired, but reading, writing, and spontaneous speech are preserved (Coslett, Brashear & Heilman, 1984).
Explanation
Pure word deafness is a subtype of central deafness. This disorder is defined as disturbed auditory comprehension without difficulties with visual comprehension. Patients characteristically have fluent verbal output, severe disturbance of spoken language comprehension and repetition, and no problems with reading or writing (Hain, 2004).
LD 10.01-Tactile Defensiveness Sensory Integration Disorder (Immature Tactile Type)
Disability Category – Specific Learning Disability
Definition
A type of sensory integration disorder specifically associated with difficulties in being touched because of an immature tactile system (Sensory processing disorder.com). Tactile defensiveness refers to a pattern of observable behavioral and emotional responses, which are aversive, negative and out of proportion, to certain types of tactile stimuli that most people would find to be non-painful (Chu, 2000).
Explanation
The tactile system is our sense of touch through different sensory receptors in our skin. We say that a child is “tactile defensive” when he or she is extremely sensitive to light touch.
One important role of our tactile system is its protective function that alerts us when something is unpleasant or dangerous. For some children, this function of the tactile system is not working normally. They may perceive most touch sensations to be uncomfortable or scary and react with a flight-or-flight response (Chu, 2000).
Theoretically, when the tactile system is immature and working improperly, abnormal neural signals are sent to the cortex in the brain which can interfere with other brain processes. This, in turn, causes the brain to be overly stimulated and may lead to excessive brain activity, which can neither be turned off nor organized. This type of over-stimulation in the brain can make it difficult for an individual to organize one’s behavior and concentrate and may lead to a negative emotional response to touch sensations Hatch-Rasmussen, 2001).
Often, children with tactile defensiveness will avoid touching the following (Sensory processing disorder.com):
- textured materials/items
- “messy” things
- vibrating toys, etc.
They may also be significantly bothered by, and avoid the following:
- a hug
- a kiss
- certain clothing textures
- seams on socks
- tags on shirts
- light touch or
- their hands being dirty
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