Esophageal motor function in patients with muscular dystrophy.

In a study designed to evaluate esophageal motor function in muscular dystrophy we examined 13 patients with myotonic dystrophy, 14 patients with "nonmyotonic" muscular dystrophy, and 8 healthy control subjects by manometric and radionuclide transit studies. Patients with myotonic dystrophy exhibited a marked weakness of esophageal contractions and upper esophageal sphincter pressure. Coordination of sphincter relaxation and peristaltic sequences remained unaltered. These changes led to delayed esophageal emptying in all patients with myotonic dystrophy. Although esophageal function was also impaired in the distal esophagus, on histologic studies, morphologic alterations were confined to esophageal striated muscle in a single patient with myotonic dystrophy. In contrast to the marked dysfunction of esophageal motility in patients with myotonia, no such alterations were observed in the "nonmyotonic" form of muscular dystrophy.