The term "diastrophic" is Greek and means "crooked". Although diastrophic dysplasia occurs in most countries, the highest prevalence is found in Finland (1 in 33,000) where the carrier rate in the population is 1 – 2% (3). The incidence in non-Finnish populations is considerably lower, being 1 in 500,000 live births (6).
Diastrophic dysplasia is caused by a mutation in the gene coding for a sulfate transporter protein that is essential for normal cartilage function. This protein is called DTDST and was first identified by Hastbacka and colleagues in 1994 (1). The gene is located on chromosome 5 (5q31-q34). Mutations in the same gene are responsible for lethal chondrodysplasias.
Proteoglycans are complex molecules that absorb water and facilitate load bearing in articular cartilage. Reduction in sulfate transporter concentrations in chondrocytes causes undersulfation of the proteoglycan matrix and predisposes individuals to early degenerative joint disease. Diastrophic dysplasia affects chondrocyte function in the growth plate, epiphyseal region and other areas such as the trachea.
The physical characteristics of diastrophic dysplasia include a short limbed form of disproportionate short stature. Both joint dislocations and joint contractures can be present. Intelligence is typically average.
Face and Skull
- narrow nasal bridge and broad midportion of the nose
- long and broad philtrum
- high, broad forehead
- square jaw
- cleft palate in approximately 50% of children
- capillary hemangiomas called an "Angel's kiss" can be present in the midforehead region. They will disappear or fade with time.
- in the majority of patients in first 2 weeks of life, cystic swellings of the ear appear but resolve spontaneously, resulting in the characteristic “cauliflower ear” deformity.
Arms and Legs:
- shortening of limbs
- "Hitchhiker’s thumb." Due to poor development of the bone supporting the thumb, the main thumb joint deviates outwards
- limited movement of the fingers due to symphalangism
- dislocations of the elbow and shoulder
- dislocated kneecap
- abnormal gait
- weight bearing on balls of feet and toes with compensatory knee and hip flexion
What Are the X-Ray Characteristics?
The radiographic features of Diastrophic Dysplasia include short and broad long bones of the limbs. The metaphyses are flared and crescent-shaped, and flattened epiphyses are typical. The epiphyses of the proximal tibias are triangular and larger than those of the distal femoral epiphyses. The metacarpals, metatarsals, and phalanges are deformed and shortened. Cervical kyphosis and thoracolumbar kyphoscoliosis are characteristic at different ages. There is a moderate narrowing of the interpediculate distances within the lower lumbar segments of spine. The hips are either partially or completely dislocated.
The condition is typically recognized at birth based on physical and radiographic evaluation. Milder variants or atypical cases may not be diagnosed until a later age. If suspicions arise during a prenatal ultrasound, molecular testing can be done from an amniocentesis sample.
In parents who already have children with diastrophic dysplasia, an ultrasound scan or molecular genetic testing (using DNA from amniocentesis or chorionic villus sampling) in the first trimester of pregnancy offers the possibility of prenatal diagnosis of this condition.
Cervical kyphosis is present in 30 – 50% of individuals. It is due to hypoplasia of the vertebral bodies and progressive degenerative changes in the intervertebral joints. Kyphosis can be sufficiently severe and will cause a predisposition to spinal cord compression and quadriplegia (weakness of all 4 extremities and incontinence). Short, sharply angulated curves are associated with severe kyphosis and increase the incidence of neurological abnormalities. Surgery may be necessary to alleviate the spinal cord compression in the neck. A halo and vest device is usually employed after surgery to support the neck until stable fusion is achieved. Occasionally, the kyphosis will resolve spontaneously.
Scoliosis, although not apparent at birth, will become severe as weight bearing increases. The curves usually develop around 5 years of age but can develop even before walking age. The spine curvature causes trunk deformity and barrel chest. Three distinct patterns of scoliosis occur: early progressive, idiopathic-type and mild non-progressive. Kyphoscoliosis occurs frequently (up to 90% of patients) in the lumbar region of the spine. Lumbar lordosis is increased due to exaggerated thoracic kyphosis and concomitant hip flexion contractures (hip joint is fixed with the thigh bent forwards).
Severe clubfoot is almost always present and typically requires surgical release. Surgery is usually undertaken around 1-year of age, to enable the child to start walking. In spite of early intervention, recurrence of the foot deformity is common and an osteotomy may become necessary. Special shoes are oftentimes required.
Progressive subluxation of the hips occurs because the soft articular cartilage is unable to perform its normal function of load bearing. Superimposed joint contractures around the hips and knees lead to restricted movement and deformity. If the deformity interferes with walking, an osteotomy is performed around the hips or knees. Due to the intrinsic cartilage abnormality, degenerative joint disease (arthritis) is common. Flexion deformities are pronounced. Knees are dislocated. Hip or knee replacement surgery is usually necessary in early to mid-adult life and typically has successful results.
Respiratory obstruction, including laryngeal stenosis, may occur in newborns. The mortality rate due to respiratory distress can approach 25% in early infancy.
Hypoplastic cartilage in the trachea and larynx causes voice abnormalities and breathing difficulty.
Small Auditory Canals
Small auditory canals are characteristic, but this does not usually impair hearing. However, deformity of the middle ear ossicles can result in
In infancy, it is important to be regularly monitored by a pediatric orthopedic surgeon so that future problems of the feet and spine can be managed and possibly evaded. Surgery is usually performed before walking age to correct foot deformities.
Later in life, patients must look out for worsening foot deformities, progressive curvature of the spine, and hip pain in early adult life (due to arthritis). Common surgical procedures intended to correct these problems include an osteotomy of the foot or lower leg (to achieve a plantigrade foot) or hip replacement surgery (for progressive degenerative arthritis).
Occasionally, spinal cord compression in the neck can lead to quadriparesis, resulting in a loss of limb function. Symptoms to watch for include a loss of walking or reduced endurance, altered sensations in the arms and legs, or incontinence. Oftentimes patients undergo spinal fusion surgery in the neck or lower back, along with decompression of the spinal cord.
Generally all skeletal dysplasias warrant multidisciplinary attention. Regular assessment by an orthopedist, geneticist, pediatrician, dentist, neurologist, and physical therapist will provide the most comprehensive treatment.
- Hastbacka, J.; Sistonen, P.; Kaitila, I.; Weiffenbach, B.; Kidd, K. K.; de la Chapelle, A. : A linkage map spanning the locus for diastrophic dysplasia (DTD). Genomics 11: 968-973, 1991.
- Jones, Kenneth L. Recognizable Patterns of Human Malformation. Philadelphia, PA: Elsevier Saunders. 2006.
- Poussa, Mikko. Merikanto, Juhani. Ryoppy, Soini. Marttinen, Eino. Kaitila, Ilkka. The Spine in Diastrophic Dysplasia. Spine; 16(8):881-887. 1991.
- Scott, Charles I. Dwarfism. Clinical Symposium, 1988; 40(1):9-10.
- Spranger, Jurgen W. Brill, Paula W. Poznanski, Andrew. Bone Dysplasias: An Atlas of Genetic Disorder of Skeletal Development. Oxford: Oxford University Press. 2002.
- Diastrophic Dysplasia Booklet http://pixelscapes.com/ddhelp/DD-booklet/
From Nemours' KidsHealth
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Relaxation Techniques for Children With Serious Illness
Nothing about serious illness is easy, but one of the hardest things for parents may be watching their child struggle with pain, stress, and anxiety.
Despite what we may sometimes tell ourselves, stress is not just "in our heads." The stress response — also called the flight-or-fight response — causes a rush of adrenaline and other hormones that trigger physical changes in the body: your heart races, your blood pressure rises, you breathe faster, your digestion slows, and your pupils dilate. Chronic stress takes a toll on the body as well as the mind.
The good news is that using a variety of mind-body relaxation techniques can help short-circuit the flight-or-fight response. Relaxation techniques not only can lessen a child's physical symptoms, they can also help him or her (and you!) regain a sense of control and confidence over a situation, helping everyone find moments of peace amid the chaos and isolation of illness and medical treatment.
Techniques That Can Help
These techniques are designed for parents and kids to practice together. Most can be done in a few minutes wherever you are, whether that's a quiet place or a crowded hospital, without any special tools.
However, it's important to note that these techniques should be used as a complement to conventional medical treatment for anxiety and pain, and not as a replacement — doing so could do a child more harm than good.
If your child is suffering from anxiety or pain, ask your doctor what can be done to help. And always check with your health care team to make sure that your child's symptoms are related to stress and not a different medical problem.
Pain and stress can leave a child breathing faster and shallower, or even holding his or her breath — all of which can actually keep the stress response going and heighten the intensity of pain. Paying attention to breathing can help calm the mind.
Try this exercise with your child:
- Step 1. Sit or lie comfortably and put one hand on your stomach, the other on your chest.
- Step 2. Close your eyes and try to relax all of your muscles, one by one, from the tips of your toes to the top of your head. Don't forget to relax the muscles in your face, neck, and jaw; you may be storing a lot of tension there.
- Step 3. Breathe deeply and regularly for several minutes— and try to make your stomach (abdomen) rise and fall, not only your chest. This will help you deepen your breath.
- Step 4. Pay attention to each breath; try to turn all your thoughts to each inhale … exhale. As you breathe out, imagine the tension leaving your body with the breath.
At first, it may be difficult for you and your child to focus on breathing. Distracting thoughts are normal — but rather than following a thought and letting it consume you, try to let it drift out of your mind, like a balloon.
Relaxation Response Method
This technique asks a person to focus on breathing and quiet the mind to create a sense of calmness and well-being. And by repeating a word, phrase, or prayer during the exercise, the mind is able to stay focused more easily. When practicing this, it's normal for thoughts to pop into the mind. Tell your child to disregard them and just focus on the word or phrase he or she is repeating.
Resembling an Eastern form of meditation, this technique — called the relaxation response — was popularized and put into Western practice in the 1970s by Herbert Benson, MD. To elicit the relaxation response, follow Steps 1-4, and then:
- Step 5. Pick a focus word, phrase, sound, or prayer such as "om," "one," or "peace."
- Step 6. As you breathe, say the focus word silently to yourself as you exhale.
- Step 7. Continue for 5 or 10 minutes, ideally building up to 10 to 20 minutes for each session.
- Step 8. When you're finished, do not stand up immediately. Continue sitting quietly for a bit, letting other thoughts back into your mind. Open your eyes, but stay sitting for another minute before getting up.
When practicing, go at your own pace. Don't feel like you have to achieve a deep level of relaxation right away. Often, feelings of calmness and well-being are felt later on or at times of crisis.
To achieve ongoing results, try to practice the technique with your child once or twice daily, but not within 2 hours after eating, as digestion can interfere with the relaxation response. Some people find that the best time to meditate is first thing in the morning, before breakfast.
A growing body of medical research suggests that imagery also can help lessen pain and anxiety, and promote positive feelings. In fact, studies have found that people who practice guided imagery during chemotherapy feel more relaxed and positive about their chemo experience than those who don't use the technique.
Guided imagery (also called "visualization") often works best when a person starts with a few minutes of focused breathing. Here's how it works: With eyes closed, imagine a safe place or a location you once visited that brought a feeling of contentment and joy. Hold on to the image of that place for a while, trying to picture all the sights and sounds:
- What does the ground beneath you feel like? Is it weather warm or a chilly? Is there a breeze?
- Are there any animal noises in the distance, or nature sounds (like running water) that you could hear?
Getting as descriptive as possible about this safe place will help you and your child get "into" the moment and feel relaxed.
Some children find this exercise more helpful when they are "guided" by a parent, another live instructor, or with a guided imagery CD or DVD.
As with meditation, distracting thoughts will float into the mind as you practice guided imagery. Acknowledge these thoughts, and then let them drift away while you move your attention back to the images in your mind and sounds you hear.
Just as pleasant images can calm the mind and soothe the body, so can music. Kids who undergo music therapy — the research-based use of music to lift moods and promote mental and physical well-being — have been found to have lowered heart rates and blood pressure, and improved anxiety.
Many hospitals provide a licensed, trained music therapist who can work individually with kids to develop a customized treatment plan that engages them in:
- active play that includes listening to music
- dancing or moving the body to music
- playing instruments or improvising on them
- singing along
To participate in music therapy, your child doesn't need to read music or have any special musical talents. And the best part is that you can practice music therapy at home. By choosing music that both you and your child enjoy — and setting aside time to listen, dance, sing, or experiment with an instrument together — you, too, can teach your child the joys of music.
Energy therapy is based on the understanding that there are electrical currents in all living organisms. This produces magnetic energy fields that extend around and beyond the body, just like the Earth's electromagnetic field. Proponents of this therapy believe that gentle, light touch or above-the-body hand movements can redirect energy to places where it's needed in an effort to bring the body into "balance" or harmony.
Energy therapy continues to be scientifically explored and, and findings note that it promotes healing as it helps kids feel more relaxed, less anxious, and less bothered by pain. It also empowers them to feel like they are in control and can do something to help themselves feel better.
Many different types of energy therapy are practiced all over the world, including Healing Touch, therapeutic touch, Reiki and Johrei (from Japan), and Qi gong (from China).
In the United States, many hospitals offer Healing Touch as a complement to standard treatments for anxiety, pain, or other medical problems, meaning that they are used with the therapies and/or medications that the medical teams order.
And some nurses, doctors, or other health care providers are certified in Healing Touch techniques through a required national certification examination. Healing Touch is the only energy therapy with this requirement. They may be able to offer this service to your child, and can teach you how to practice Healing Touch at home.
If you like to take a more hands-on approach to soothing and comforting your child, you might prefer massage. The benefits of massage are well known, offering muscle relaxation and increased blood flow and oxygen to body parts to help alleviate stress and ease pain.
But some types of massage are not recommended for certain types of conditions, so check with your doctor first before massaging your child or taking your child to a massage therapist.
The most common forms of massage used in complementary medicine include:
- Swedish massage. Therapists use their hands to move muscles and joints with long, gliding strokes, tapping movements, friction (made by moving hands quickly) and kneading. Massage oils may be used, so be sure to tell the therapist about any allergies or sensitivities to ingredients that your child may have.
- Deep-tissue massage. Many of the same techniques are used as in Swedish massage, only therapists apply more pressure to specific areas, concentrating on the deeper layers of muscles and connective tissue.
- Trigger-point massage. Like deep-tissue massage, this technique massages deeper layers of tissue, focusing on what therapists call trigger points ("knots") within the connective tissue or muscles that are usually painful when pressed.
Many hospitals have massage therapists on hand to offer massages to both patients and their family members, so find out if massage therapy is offered at your hospital.
These are just a few of the many methods designed to help patients and families cope with pain and anxiety. Many people find that yoga, stretching, or light, gentle exercise also helps to quiet the mind and soothe the body.
To learn more about relaxation techniques, talk to your child's health care team.
Reviewed by: Walle Adams-Gerdts, BA, RN, HTCP/I
Date reviewed: September 26, 2016