Teaching Video Neuro Images : Bent spine syndrome as an early presentation of late-onset Pompe disease

Abstract

Bent spine syndrome (BSS), an abnormal trunk anteroflexion of at least 45° that increases during walking and abates in supine position, is described in parkinsonism and myopathies.1 We report a 56-year-old man with genetically proven late-onset Pompe disease (LOPD) showing BSS (figure 1 and video 1 at [Neurology.org][1]). He complained of axial weakness that progressively forced him to walk stretching his arms backward since his 20s. Whole-body muscle MRI revealed severe fatty replacement of lumbar paraspinal (figure 2) and iliopsoas muscles, and spirometry showed restrictive ventilatory defect. Periodic acid-Schiff–positive vacuoles and reduced acid α-glucosidase activity were demonstrated in muscle biopsy. While lumbar hyperlordosis is a typical feature of LOPD, other trunk abnormalities may appear early in the disease. LOPD must be included in the differential diagnosis of BSS.2 [1]: http://neurology.org/lookup/doi/10.1212/WNL.0000000000004119