The authors retrospectively analyzed 205 patients affected with low back pain and submitted to conventional radiology, CT scan, MR. The purpose of the study was that of gaining a better understanding of the mechanisms caused by the occurrence of spondylosis and its evolution. In light of the most recent literature, the authors conclude: 1) the degenerative process nearly always initiates with laceration of the anulus; 2) dysfunction of the disc then has repercussions on the posterior structures at varying times and with different modalities; 3) symptoms do not always coincide with radiological findings. Thus, the authors believe that for a more complete understanding of the etiopathogenesis and the evolution of spondylosis, further studies involving long-term follow-up of a young population, in relation to clinical and MR findings are needed. MR is the method of choice in determining disc degeneration.