Musculoskeletal Key

In genetic counseling, it is important to distinguish this autosomal dominant type from the clinically similar X-linked dominant type, which is fatal in hemizygous males. Severely affected infants are either…

Clinical Manifestations. At birth, weight is normal but body length is reduced. The configuration of the head and face is normal. The elbows do not extend fully. The excessive length…

Clinical Manifestations. The moderately short stature of the short-limb type is evident by 18 to 24 months of age. The head and face are not affected. The wrists are prominent…

Clinical Manifestations. Clinical findings vary widely. Formerly, patients with similar but less severe signs were thought to have a variant form or a different condition. The differences, more apparent than…

Clinical Manifestations. Growth retardation is usually not apparent until the child is 1 year old and often not until age 2 or 3. A delay in walking or an abnormal…

In the teenage period, slowly progressive symptoms such as paresthesias, weakness, pain, and paraplegia develop and may be aggravated by obesity and prolonged standing or walking. Initially, the patient can…

Hypochondroplasia is inherited as an autosomal dominant trait, but most cases appear to be sporadic, presumably the result of a spontaneous mutation affecting FGFR-3, resulting in a milder dysplasia than…

Midfacial hypoplasia of variable degree is manifested by a flat or depressed nasal bridge, narrow nasal passages, and malar hypoplasia (see Plate 4-2). The nose has a fleshy tip and…

Physical Examination. Measurements of head circumference, height, weight, and arm span are taken, and body proportions are evaluated. A careful examination should be done for nonosseous signs such as cleft…

Skeletal dysplasias, or chondrodystrophies, are a heterogeneous group of disorders resulting in short-limb or short-trunk types of disproportionate short stature. In the types of dwarfism that primarily affect the limbs,…