Electromyographic abnormalities in osteosarcoma arising in Paget disease of the vertebral column

The case of a patient with low back pain and Paget disease of the L5, S1 vertebrae is presented. Electromyography revealed dysfunction in both the paraspinal and gluteal muscles. Postmortem examination showed sarcomatous transformation of the vertebrae with nerve root compression and skeletal muscle infiltration by tumor. The electromyographic abnormalities are correlated with the pathologic findings. The clinical features of neurologic dysfunction in Paget disease of the vertebral column and in osteosarcoma arising in Paget disease of the vertebral column are reviewed. Electromyography can provide valuable information in the evaluation of the patient with Paget disease of the vertebral column who is suspected of having neurologic dysfunction.