Fig. 1

Lateral spine and hip radiographs of two SEDT-XL patients. a, b Radiographs taken from the proband with the c.1A > T, TRAPPC2 variant at age of 45 years. a Thoracolumbar lateral spine shows uniform platyspondyly and hump-like bony projections at the centroposterior portions of upper and lower endplates, and narrowing or almost obliteration of the intervertebral disc spaces. b Pelvis radiograph shows narrow iliac wings with relatively long ischium and pubic bones, deep acetabulum and degenerative osteoarthtis with narrow hip joints. c, d Radiographs from the proband with the c.40delG, TRAPPC2 variant at age 15 years. c Spine lateral radiograph shows platyspondyly with elongated vertebral bodies and hump-like bony protrusion at the upper and lower endplates, dominantly noted in the lumbar spine. d Hip shows relatively long ischium and pubic bones. Deep acetabulum and dysplastic femoral heads with premature degenerative hip joint narrowing are noted