Small detached disc fragment lying above the L4-L5 disc of right posterolateral location, compressing and displacing posteriorly the adjacent L4 nerve root. It elicits an isosignal to the intervertebral disc on T1, slightly high signal on T2, and STIR with peripheral enhancement on postcontrast sequences, suggestive of a free disc fragment that has no continuity with the native L4-L5 disc.