A fusion cage 10 having an external thread 12 can be surgically inserted into a threaded bore extending laterally between the adjacent bony structures such as two vertebrae 94, 95 with the thread 12 penetrating into cancellous bone of each of the vertebrae 94, 95. The fusion cage 10 is easily screwed...http://www.google.ca/patents/US5026373?utm_source=gb-gplus-sharePatent US5026373 - Surgical method and apparatus for fusing adjacent bone structures
