Definitions A-K

Acromelia—shortening of the terminal parts of the limbs (hands and feet) in relation to the upper and middle limb segments.

Atlantoaxial Instability— abnormal extra motion occurring between the first and second cervical vertebrae(C1 and C2). This extra motion places the spinal cord at risk as it travels between C1 and C2. Typically this results from either an abnormal odontoid process or ligamentous laxity.

Amniocentesis- a procedure typically done with ultrasound guidance in which a needle is passed through the abdominal wall and the uterus and into the fluid which surrounds a baby. Some of the amniotic fluid is then removed thru the needle and this fluid can be used for various types of genetic testing. This is typically done at 16-18 weeks gestation.

Anterior- relating to the front of the body.

Autosomal Dominant—when a condition is caused by having only a single mutant copy of a particular gene and that gene is located on one of the 22 pairs of autosomal chromosomes.

Autosomal Recessive— when a condition is caused by having two mutant copies of a particular gene and that gene is located on one of the 22 pairs of autosomal chromosomes.

Brachydactyly- Short fingers or toes.

Carpals- the eight bones of the wrist.

Central Apnea- temporary cessastion of breathing due to the failure of the respiratory centers in the brain to properly control the process of breathing.

Cerebral vascular system - the system of blood vessels in which blood flows to and from the brain.

Cervical Spine—relating to the vertebrae found at the level of the neck.

Chondrocytes - cartilage cells.

Chorionic Villus Sampling (CVS)- a procedure typically done with ultrasound guidance in which a needle is passed through the abdominal wall and the uterus and into the developing chorionic tissues. Some of the tissue is removed thru the needle and can be used for various types of gentic testing. This is typically done at 9-12 weeks gestation.

Cloverleaf Skull - a severe form of craniosynostosis that involves a premature closure of every suture of the skull.

Club Foot - a congenital anomaly of the hindfoot that restricts the ability to stand with the sole of the foot flat on the ground.

Coxa valga- an abnormality of the hip in which the angle between the top of the femur and the femoral shaft is larger than normal.

Coxa vara - an abnormality of the hip in which the angle between the top of the femur and the femoral shaft is smaller than normal.

Craniosynostosis - a premature closure of the sutures or growth plates in the skull.

Diaphyseal— of or relating to the diaphysis.

Diaphysis—the middle or shaft part of a long bone.

Disproportionate short stature—short stature where the the limbs or trunk are not in proportion to each other.

Distal—on the limb in the direction away from the body.

Ductus arteriosus - one of the two shunts in the fetal heart located between the pulmonary artery and aorta. This passage way allows blood to bypass pulmonary circulation. Oxygen is delivered to the fetus via the placenta and the mothers blood. Once the baby is born and the lungs inflate, the shunt closes so that pulmonary circulation is separated from systemic circulation.

Dysplasia—an abnormality of development of a body tissue or organ.

Echocardiogram - A procedure that uses sound waves and echoes to show the structure and movement of the heart.

Endochondral Bone Formation—the type of bone formation that occurs at the growth plates of the long bones.

Epiphyseal—of or relating to the epiphysis.

Epiphysis—the ends of the bone of the long bones.

Femur- thighbone; long bone located between the hip and knee.

Fibula- the outer and more narrow bone of the two bones connecting the knee and ankle.

Flexion/Joint Contractures—inability to fully straighten the joints.

Fontanel-the "soft spots" between the incompletely fused cranial bones.

Foramen Ovale - One of the two shunts in the fetal heart that allows blood to flow from the right atrium to the left atrium, so that blood bypasses pulmonary circulation. This shunt should close within the first year of life when the lungs are functional and pulmonary pressure decreases.

Genitourinary tract- the system composed of the urinary and reproductive organs.

Genu Valgus—bowing of the legs inward so that the knees point inward. This is also called knock-knees.

Genu Varus—bowing of the legs outward so that the knees turn to the sides. This is also called bow-legged.

Hydrocephalus— a condition that is characterized by a dilatation of the cerebral ventricles caused by an obstruction of the fluid passages inside the brain. The fluid accumulates, causes increased pressure and can lead to enlargement of the head, mental or neurological problems. Also called water on the brain.

Hydromelia- dilated spinal canal.

Hyperplasia- an abnormal increase in tissue/bone growth.

Hypoplasia—underdevelopment of body tissue or organ.

Hypotonia- A decrease in muscle tone or strength.

Hypoxia- Inadequate amount of oxygen getting to the bodily tissues.

Ilia- The wide, upper part of the pelvis.

Interpediculate Distance- The width of the vertebrae of the spine, as measured between the pedicles

Kyphosis - A rounding or hunching over of the back.