What Are Biologics?

Biologics refers to a group of substances that your surgeon may inject in the office or use during your surgery to help you heal. They contain specific material or cells that have an effect on other nearby cells and processes in your body. Depending on the contents, they potentially can help stimulate your body to form new bone, build new blood vessels, or limit damaging inflammation.

Where do biologics come from?

Some biologics are harvested directly from you! By taking some of your own blood, bone marrow, or fat cells, your surgeon can isolate certain types of your own stem cells and growth factors. Examples of biologics that can be harvested from your own tissue include platelet-rich plasma (PRP) and bone marrow aspirate concentrate (BMAC).

Other biologics are harvested from other sources, usually from human donors. These commercially available biologics have many different brand names, which can be confusing. On individual product websites, you can find more information about what the biologics actually contain. However, the following are some examples of the substances found in commercially available biologics:

  • Stem cells and/or bone cells
  • Bone morphogenetic protein (BMP) - a signal that helps new bone to form
  • Platelet-derived growth factor (PDGF) - a signal involved in the healing process after injury
  • Vascular endothelial growth factor (VEGF) - a signal that stimulates new blood vessels to form
  • Amniotic membrane
Bone marrow removal from patient

Above, bone marrow is being harvested from the hip bone with a long needle. This fluid, which is rich in stem cells and other healing factors, is an example of a biologic that can be used to augment healing. 


Your foot and ankle orthopaedic surgeon may recommend a biologic injection to treat conditions in the office. For example, PRP injections may be used for Achilles tendinitis, plantar fasciitis, or ankle arthritis. There is still debate in the scientific community about the effectiveness of these injections, and research is continuing.

Your surgeon also may recommend using biologics during your surgery. In foot and ankle surgery, they are most commonly used to help bone healing. Many foot and ankle surgeries involve fusions, or trying to get two or more separate bones to become one. In certain situations, it can be more difficult for bones in the foot to join together, and using biologics can help increase the chance of the bones healing properly.

Risks and Complications

Though uncommon, your immune system may react negatively to the biologics. Using biologics from your own body lowers the chance of this happening, and commercially-available biologics are tested for disease and treated to minimize reactions.

You may experience local pain or changes from obtaining the material from your own body, and you may be limited in the amount available in your body. Biologics from donor sources can be significantly more expensive and vary in quality. If the biologics come from cadaver sources, there is a small risk of transmission of infection. Talk to your foot and ankle orthopaedic surgeon to discuss the pros and cons of each option for your specific situation.

Can biologics help me avoid surgery?

Because so much depends on your specific situation, you should discuss your goals with your foot and ankle orthopaedic surgeon before considering biologics. We know that some biologics can help your bones heal together when used during surgery. However, there is debate about how helpful they are for other conditions. 

For patients with arthritis, for example, these injections are not going to regenerate lost cartilage or substitute for surgery, but they may decrease inflammation and improve the symptoms. As long as you are making an informed choice, and have agreed upon reasonable expectations with your surgeon, biologics can be a useful tool in your treatment plan.

A Final Note

This is a very exciting field with new products being developed and new studies being reported almost every year. The above is a current summary of this area of medicine, but given the rate of change, it is quite possible to be different in the future as this field develops.


Original article by Elizabeth Cody, MD
Contributors/Reviewers: David Lee, MD

The American Orthopaedic Foot & Ankle Society (AOFAS) offers information on this site as an educational service. The content of FootCareMD, including text, images, and graphics, is for informational purposes only. The content is not intended to substitute for professional medical advice, diagnoses or treatments. If you need medical advice, use the "Find a Surgeon" search to locate a foot and ankle orthopaedic surgeon in your area.