with myotonic dystrophy, EMG may show myotonic discharges. These discharges
may occur spontaneously or be elicited by moving the recording needle
or percussion on the muscle. Muscle biopsy may shows an arrest of fetal
Mothers with myotonic dystrophy have characteristic facies, clinical or
EMG myotonic responses, and a minimal degree of mental delay may be present.
Clinical myotonia is readily elicited in the mother (inability to open
eyes quickly after they have been briefly closed or inability to extend
the fingers after a handshake). The diagnosis is established by DNA testing.
The abnormal site is at 19q13.3. The likelihood of giving birth to another
infant with neonatal myotonia in subsequent pregnancy is about 30%. Treatment
is supportive. Arthrogryposis should be managed nonsurgically in the neonatal
period. Surgical management of joint deformities may be necessary later
Fascioscapular Humeral Dystrophy
fascioscapular humeral dystrophy is a rare condition. It is encountered
in two situations: (1) in a neonate who has weakness and hypotonia that
spares the extraocular movements and the lower extremities, who also has
a family history of facioscapular humeral dystrophy; or (2) in a neonate
with facial and shoulder girdle weakness and a muscle biopsy that exhibits
inflammatory changes. Serum creatine phosphokinase is moderately elevated.
Treatment is supportive.
muscular dystrophies are a group of disorders that affect the muscles.
They produce elevated serum creatine phosphokinase and a characteristic
muscle biopsy pattern. The characteristic muscle biopsy changes are replacement
of muscle by fat and connective tissue and evidence of muscle fiber necrosis