My husband had spine surgery that was pretty complicated. I guess they used a new kind of bone graft substitute. He evidently needed more bone than he could donate to himself. What does this stuff look like? Is it a patch or what?

Bone graft substitute is a fairly new material on the market. There are five basic types but many products within those five types. The composition of each product varies. Some are incorporated into a sponge, which is then pushed into place where needed.

Some bone graft substitutes are injected whereas others are in paste or strip form and applied directly to the surface of the bone defect. They also come in pellet, block, or granular form.

Besides differences in composition, there are also differences in the strength of these materials. How fast or slow they are absorbed by the body is also important. Too fast or too slow can affect the final results.

The FDA must approve bone graft substitutes. However, studies to back up how well they work by patient type or bone location are very limited. The same is true for identifying which type (paste, chips, pellets, etc.) works best. More studies are needed to compare each type.