Late-Onset Axial Myopathy and Camptocormia in a Calpainopathy Carrier

Abstract

Camptocormia is a debilitating gait disorder characterized by the hyperflexion of the thoracolumbar spine during the upright position. Its etiologies are heterogenous, including parkinsonism and various neuromuscular disorders. Here, we report a camptocormia patient due to a late-onset axial myopathy with numerous lobulated fibers. The patient's father reportedly had similar symptoms. Myriad lobulated fibers are common among patients with an autosomal recessive muscular dystrophy due to calpain-3 gene (CAPN3) mutations or calpainopathy. CAPN3 sequencing revealed a single c.759-761delGAA mutation. Calpainopathy carriers are generally asymptomatic. The presence of lobulated fibers in this patient suggests that camptocormia could be a manifestation of calpainopathy carrier, although the possibility of a coexisting undiagnosed myopathy cannot be excluded. The current patient should spur the evaluation of camptocormia among calpainopathy carriers.