Fig. 2

The histological images of the intervertebral discs at 12, 24, and 48 weeks after surgery. a–d The HE stainings of nucleus pulposus. e–h The HE stainings of cartilage endplates. i–l The Masson trichrome stainings of intervertebral discs. m–p The Safranin O stainings of intervertebral discs. q–t The proteoglycan stainings of intervertebral discs. u–w The Sirius Red stainings of intervertebral discs