Amyoplasia revisited.

Amyoplasia is a specific type and the most common form of arthrogryposis (multiple congenital contractures). It is a clinical diagnosis at this time. Care should be used making the diagnosis because of the implications for recurrence, natural history, associated anomalies, and both etiology and pathogenesis. We reviewed over 600 published reports and 2,500 individual records to identify the 560 individuals reported here. Affected limbs had characteristic positions with fatty-fibrous replacement of muscle. Upper limb involvement was usually characterized by extended elbows. Lower limbs were held in various positions at birth; however, equinovarus positioning of feet was almost always present. Symmetric involvement was common. Among 560 affected individuals, subtypes were identified: four-limb symmetric involvement (331/560 = 55.9%), severe involvement (41/560 = 7.3%), three-limb involvement (27/560 = 4.8%), upper limb only Amyoplasia (ULA; 94/560 = 16.8%), and lower limb only Amyoplasia (LLA; 25/560 = 15.5%). Discordant monozygotic twinning was increased, occurring in 6.6% (37/560; OR 10.9). A variety of additional anomalies were seen, attributed to apparent vascular compromise. Gastrointestinal vascular compromise-type anomalies were present in 9.1% (51/560), trunk muscle defects in another 2.7% (15/560), digit compromise in 12.1% (68/560), constriction rings in 4.3% (24/560), and perinatal long bone fractures in 10.5% (59/560). Although prenatal ultrasound became the standard of care in 1990, only about one quarter of affected pregnancies were diagnosed prenatally since 1990. Amyoplasia appears to be completely sporadic. Novel pathogenetic mechanisms for the congenital anomalies seen in Amyoplasia need to be identified.

Majewski osteodysplastic primordial dwarfism type II (MOPD II): natural history and clinical findings.

A description of the clinical features of Majewski osteodysplastic primordial dwarfism type II (MOPD II) is presented based on 58 affected individuals (27 from the literature and 31 previously unreported cases). The remarkable features of MOPD II are: severe intrauterine growth retardation (IUGR), severe postnatal growth retardation; relatively proportionate head size at birth which progresses to true and disproportionate microcephaly; progressive disproportion of the short stature secondary to shortening of the distal and middle segments of the limbs; a progressive bony dysplasia with metaphyseal changes in the limbs; epiphyseal delay; progressive loose-jointedness with occasional dislocation or subluxation of the knees, radial heads, and hips; unusual facial features including a prominent nose, eyes which appear prominent in infancy and early childhood, ears which are proportionate, mildly dysplastic and usually missing the lobule; a high squeaky voice; abnormally, small, and often dysplastic or missing dentition; a pleasant, outgoing, sociable personality; and autosomal recessive inheritance. Far-sightedness, scoliosis, unusual pigmentation, and truncal obesity often develop with time. Some individuals seem to have increased susceptibility to infections. A number of affected individuals have developed dilation of the CNS arteries variously described as aneurysms and Moya Moya disease. These vascular changes can be life threatening, even in early years because of rupture, CNS hemorrhage, and strokes. There is variability between affected individuals even within the same family.