Early in the twentieth century there were scattered reports of congenital myopathy, but the status of this condition was difficult to evaluate. Some cases may have represented congenital myotonic dystrophy or one of the congenital myopathies described later. In 1957, Banker and associates described 2 patients (siblings), 1 dying 1.5 h after birth and the other dying at the age of 10 months of a congenital muscular dystrophy (CMD) with arthrogryposis. The pathologic changes consisted of muscle fiber degeneration, variation in fiber size, fibrosis, and fat cell replacement. The central and peripheral nervous systems were intact. The severity of the degenerative changes was such that a developmental disorder of muscle could be excluded. Pearson and Fowler, in 1963, reported a brother and sister with similar clinical and pathologic findings, and Walton and colleagues described yet another patient, 4 years of age. By 1967, Vassella and colleagues were able to collect 27 cases from the medical literature and to add 8 cases of their own. The high incidence of sibling involvement pointed to an autosomal recessive inheritance.
Preceding the modern genetic findings, in 1976,
Bethlem and van Wijngaarden described an autosomal dominant, early-onset limb-girdle dystrophy in 28 members of 3 unrelated Dutch families. Flexion contractures of the elbows, ankles, and hyperextensible interphalangeal joints of the fingers were present from the beginning stages of weakness, but neither the weakness nor the contractures were disabling. Also unlike Emery-Dreifuss dystrophy, contractures of the neck and spine were not present. Uniformity of clinical expression, slow progression with long periods of arrest, and normal longevity are other important features of the illness. Mohire and coworkers have proposed the designation Bethlem myopathy. A milder form that is allelic with the Bethlehem type is termed Ulrich myopathy; many of these patients survive into their fifties because of the slow progression of disease.
Defined as a muscle dystrophy already present at birth, often with contractures of proximal muscles and trunk, the severity of the weakness and degree of progression have varied widely. Of the 8 cases reported by Rotthauwe and colleagues, 1 had a benign course, but the others all had weakness and hypotonia at birth, and difficulty in sucking and swallowing had interfered with nutrition. Their oldest patients, 14 and 23 years of age, and several others had walked, but at a late age. In the Finnish series of Donner and associates, congenital dystrophy accounted for 9 percent of the 160 cases of neuromuscular disease seen at their hospital over a decade. The weakness and hypotonia were generalized, and 3 had ECG abnormalities. The CK values were elevated and the EMGs were myopathic.