What would cause an adult to have woven or unorganized bone?

In adults woven bone is created after fractures or in Paget's disease. Woven bone is weaker, with a smaller number of randomly oriented collagen fibers, but forms quickly; it is for this appearance of the fibrous matrix that the bone is termed woven. It is soon replaced by lamellar bone, which is highly organized in concentric sheets with a much lower proportion of osteocytes to surrounding tissue.

After a fracture, woven bone forms initially and is gradually replaced by lamellar bone during a process known as "bony substitution."