The authors report the case of a 15-year-old boy who presented with left shoulder pain and paresthesia of the left hand. Imaging studies revealed an osseous lesion compressing the C-8 nerve root. The patient underwent tumor resection followed by instrumentation-augmented fusion. Histological findings were consistent with osteochondroma. The tumor most likely originated from the articular cartilage between the first rib and T-1 or between C-7 and T-1. The correct diagnosis, therefore, was dysplasia epiphysialis hemimelica (DEH), also known as Trevor disease. To the authors' knowledge, this is the first report of DEH involving the spine.