Nicole DePaul was born with diastrophic dysplasia, a rare form of skeletal dysplasia. She has mobility problems and walks with the aid of crutches, or uses a scaled down scooter to travel longer distances.
When hip pain and discomfort caused further mobility problems, DePaul sought medical counsel at the
Kathryn O. and Alan C. Greenberg Center for Skeletal Dysplasias in Manhattan where doctors advised her she'd need a double hip replacement in the foreseeable future.
Since early childhood DePaul said she's had 25 surgeries to correct club feet and straighten her hips, knees and legs so she could walk. DePaul is a short statured person and among the almost 30,000 dwarfs who live in the U.S., according to the advocacy association Little People of America. Dwarfs (also called little people) are short-statured adults under 4', 10" tall.
"Of course I'm not looking forward to more surgery," DePaul said, "but the Hospital for Special Surgery is a godsend for little people like me. Before the Greenberg Center opened many of us had to go out state for treatment."
There are more than 300 distinct types of skeletal dysplasias that affect the body's bony structure and most of them lead to "dwarfing conditions," according to Cathleen Raggio, MD, orthopedic director for Skeletal Dysplasias at the Greenberg Center. The center is the only one in the Northeast to provide multidisciplinary, holistic healthcare services for infants, children and adults with skeletal dysplasias, the Hospital for Special Surgery is No. 1 for orthopedics in the U.S., according to the 2011 U.S. World and News Report Best Hospitals list.
Three Common Dysplasias
Of the three types of skeletal dysplasias - achondroplasia, pseudoachondroplasia and diastrophic dwarfism - achondroplasia is the most common form of skeletal dysplasia that leads to dwarfism, Raggio said.
|ROLE MODELS: Nicole DePaul, pictured with her husband, Vince, and daughter, Mackenzie, has sought medical help from the Kathryn O. and Alan C. Greenberg Center for Skeletal Dysplasias at the Hospital for Special Surgery where doctors advised her she'd need a double hip replacement in the foreseeable future. photo courtesy Nicole DePaul
"It's caused by mutation, a change in the genetic code in one amino acid that leads to a change in the fibroblast growth factor receptor 3 (FGFR3) that affects growth plates and leads to dwarfing conditions," Raggio said. "Ninety-nine percent of people diagnosed with achondroplasia have the same type of mutation."
This mutation affects endochondal-bone formation or the long bones in the body, the mid-face and narrows the mid-portion of the spine, the interpedicular distance, Raggio said. The ends of the body's bones don't form as they do in an average-sized people and that leads to a certain phenotype. For people with achondroplasia, that phenotype is they're short statured and have rhizomelia. The bones closest to the trunk of the body, the femur and humerus are shorter than the tibia, radius and ulna. The mid-face, nose and space between the eyes isn't well formed and is known as hypoplastic mid-face.
Furthermore, eustachian tubes are angled differently, a difference that can cause ear, nose and throat problems, Raggio explained. Infants born with achondroplasia have spinal stenosis, a narrowing in the spinal canal at the base of the skull where the spinal cord and the brain meet.
Achondroplasia is an autosomal dominant condition, and most people with it have average-sized parents. However when one parent has achondroplasia, there's a 50 percent chance their child will have it too.
People with pseudoachondroplasia have normal-sized heads and faces but disproportionately long body trunks with some lordosis (swayback) that occurs when the spine curves in too far. They have short legs and may be knock kneed or bowlegged.
According to Raggio, pseudoachondroplasia is caused by mutations in a totally different gene mutation called COMP Like achondroplasia, pseudoachondroplasia is inherited in an autosomal dominant pattern. When one parent inherits the mutated gene, he or she has a 50 percent chance to pass it on to children.
Pseudoachondroplasia may result in degenerative joint disease which may require corrective hip surgery at an early age.
"My 5-year-old daughter has pseudoachondroplasia she's inherited from her father," DePaul said.
Both father and daughter experience pain and discomfort from osteoarthritis, a trait of this type skeletal dysplasia, and have limited range of motion at the elbows and hips. Due to spinal cord compression both had spinal fusions (surgery to join two or more spinal bones and relieve pain), and wore a halo devise attached to the outer skull for 3 months. A halo device is worn to provide skeletal traction and minimize neurological damage.
Diastrophic dwarfism, also called diastrophic dysplasia, is more deforming type of skeletal dysplasia.
Some problems that may occur are multiple joint contractures, kyphosis and scoliosis.
"Those affected with this type skeletal dysplasia often need crutches and may adopt a swing through gait rather than walking," Raggio said. Diastrophic dwarfism is an autosomal recessive disorder resulting when a person inherits two copies of a gene called DTDST with a mutation.
"We know we can't fix the genetic causes for skeletal dysplasias," Raggio pointed out. "People with skeletal dysplasias generally do well but may require surgical intervention from time to time. Surgery is performed only when absolutely necessary."
"School brings its own unique set of challenges for each child," Raggio said. "Parents need to work with the school to meet children's needs."
"My son's school was very cooperative," said Emily Camenga, BSN, RN, mother of 6-year-old, Seamus, who has been diagnosed with achondroplasia. "Step stools are available for him in the classroom, water fountain and bathroom. We keep these aids at home and bring along a fold-up stool when we travel with him."
"I think it helps our 5-year old daughter, Mackenzie, to have short-statured parents as role models," DePaul said. "Mackenzie's 31 inches tall, and the school psychologist told me when the other kids call her a baby and try to pick her up she tells them she's small like her mom and dad and not their baby."
"Little People have can-do attitudes and with medical assistance and family and school support they can do amazing things," Camenga concluded.
Joan Fox Rose is a frequent contributor to ADVANCE.