246
MINOR SYNDROMES
Kniest’s
Disease
By Robert J. Gorlin
The disorder described by Kniest in 1952 is a rare form of disproportional dwarfism often confused with Morquio’s disease or metatropic dwarfism. It is uncertain at this writing whether the disorder is heritable. The face is round with the midface flat and the nasal bridge depressed, giving the eyes an exophthalmic appearance. The neck is short and the head appears to sit upon the thorax. Dislocated hips are common at birth. Lordosis and kyphoscoliosis usually develop within the first few years of life. Inguinal hernia is common even in females. The child may not sit or walk until the age of 2 and 3 yr, respectively. By that time, most but not all joints have become progressively enlarged, stiff, and painful. For example, movement at the metacarpophalaneal joint is normal but the child cannot make a fist. The fifth fingers are generally excepted. Gait is markedly altered. Severe myopia, lattice degeneration, retinal detachment and cataract may be present. Cleft palate may occur. Conduction deafness may develop before puberty. Roentgenographically, the cranium is large in comparison with the facial skeleton. Platyspondyly, especially of the upper thoracic spine, is severe. The interpediculate distance of the lumbar spine narrows sacrally. Bones of the upper limbs are short. The metaphyses of long bones flare and the epiphyses are large, irregular, and punctate. The pelvic bones are very small, especially in relation to the large capital femoral epiphyses and proximal metaphyses. There may be coxa vara. The trochanter is prominent. References:
1. Kniest W: Z Kinderheilk 70:633, 1952 2. Roaf R, et al: Dev Med Child Neurol 9:463, 1967 3. Siggers DC: Birth Defects (in press)
Larsen’s By William
Syndrome H. McAlister
This disorder is characterized by multiple joint dislocations and flat facies. Any joint may be dislocated, but usually the large ones are affected. Other roentgen findings include supernumerary carpal and tarsal bones, resistant clubfoot, accessory ossification centers at proximal metacarpals, broad thumbs, distal phalangeal and metacarpal shortening, multiple vertebral anomalies, flattened frontal bone with hypertelorism, and micrognathia. Cleft palate, congenital heart disease, and early respiratory difficulty may be present. The recessive form lacks the abnormal facies. References:
1. Larsen LJ, Schottstaedt ER, Bost FC: J Pediatr 37574, 1950 2. Latta, RJ, Graham CB, Aase J, et al: J Pediatr 78:291, 1971 3. Silverman FN: Ann Radio1 15:297, 1972 Seminars
in Roentgenology,
Vol. VIII, No. 2 (April),
1973