Originally Posted by teteri66

BMP is what motivates your own bone cells to grow. It just works at the very beginning, to kind of jump-start your own cells. I think it primarily works within the first two weeks.

The initial issues with off-label use of BMP in the cervical spine were problems with inflammation -- so much so quickly that it tended to choke the patient by closing off the airways. In the lumbar spine, the main problem is with it growing too much and encasing the surrounding nerves in what turns out to be hard bone.