Magnetic resonance images of the lumbar discs of 44-year-old identical twins. Note similarities in the contours of the end-plates, particularly at L1-L2 (white arrow head). The spines also show similar degenerative changes in the disc, particularly at L4-L5 (white arrow). From , with kind permission from the authors and publishers.
Urban and Roberts Arthritis Res Ther 2003 5:120 doi:10.1186/ar629