Figure 1. Changes in the intervertebral disc (IVD) height index (DHI) after anular puncture and recombinant human growth and differentiation factor-5 (rhGDF-5) injection.
In a needle-puncture model of disc degeneration (4 weeks) in adolescent (5–6 months-old) rabbits, a single injection of rhGDF-5 restored disc height (A). In a study using 2-year old rabbits, rhGDF-5 disc height was also effectively recovered (B). (Modified from Chujo T, et al. Effects of growth differentiation factor-5 on the intervertebral disc- in vitro bovine study and in vivo rabbit disc degeneration model study. Spine 2006;31(25):2909-17 and Chujo T, et al. In vivo effects of recombinant human growth and differentiation factor-5 on the repair of the mature rabbit intervertebral disc. Spine J, 6(5):23S–24S, 2006 (North American Spine Society, 21st Annual Meeting Proceeding, abstract). AF: annulus fibrosus; PBS: phosphate-buffered saline.