Five patients with long-standing, severe rheumatoid arthritis who developed cervical myelopathy at the subaxial levels are presented. In each patient the myelopathy occurred in the absence of major subluxation. At laminectomy the cause of the cord compression was found to be a band-like mass of ligamentous and granulation tissue in the posterior half of the extradural space, extending to the underlying portion of the dura and forming a constricting ring. In three patients this constricting ring was released by longitudinal division of the dura followed by application of a fascial patch graft. This release seems to be essential for effective decompression of the cord and good neurological recovery was achieved in these three patients. Of the other two patients, the result was fair in one and poor in the other, this latter result being due to severe intra-operative bleeding with a massive wound haematoma.

1. Because of the importance of nutrition of the intervertebral disc in relation to its disorders, a detailed study has been made of the neighbouring vasculature of the vertebral body.

2. This has been made possible by an injection technique involving prevention of leakage by freezing with liquid nitrogen.

3. By this method capillary beds are found in the vertebral end-plate cartilage in the adult. A very fine subchondral post-capillary venous network has been demonstrated draining by short vertical tributaries to a much coarser horizontal collecting vein system connecting with the familiar basivertebral system.

4. This arrangement may be of special importance in the nutrition of the intervertebral disc.