Fig. 2From: Transforaminal endoscopic lumbar discectomy with two-segment foraminoplasty for the treatment of very highly migrated lumbar disc herniation: a retrospective analysisPreoperative evaluation on sagittal view of T2-weighted MRI. Line b, c, and d indicate the boundary for very-highly, highly, and moderately migrated herniation, respectively; the white arrow indicates the ruptured anulus fibrosusBack to article page