This was a retrospective study about 44 cases of de novo MM diagnosed between January 2003 and December 2013 at the clinical hematology department of the main military hospital in Tunis. Classification of bone lesions was based on the staging of Durie and Salmon(DS), Durie and Salmon Plus (DSP) and the MPSS score (MRI-based prognostic score for multiple myeloma).Radiological abnormalities were found in 81.8% of cases on RS and in 75% of cases on spinal cord MRI. Classification according to MPSS score: (22.7%) stage IA, (13.65%) stage IB, (38.65%) stage II and (25%) stage III. Classification according to DSP showed that 22.7% were stage IA, 13.65% stage IB, 38.65% stage II and 25% stage III. Spinal cord MRI revealed spinal cord compression (SC) in 31.8% of cases, and radicular compression (RC) in 15.9%. The number of patients with normal RS and pathological spinal cord MRI was 14 (31.8%).