L4/5 disc foramen-internal type prolapse is a relatively rare type of disc herniation in which the patient has significant pain due to the disc protruding in a narrow nerve channel and the disc compressing two nerve roots. In the past, this type of disease required chiseling of the articular eminence, removal of the disc and then internal fixation. However, the application of lateral approach microscopy allows the procedure to be completed without damaging any bony structures. The large piece in the picture is the disc protruding inside the foramen, and the other piece is the disc protruding outside the foramen.