Orthopedics Fractures & Broken Bones Nonunion Is When Your Broken Bone Doesn't Heal By Jonathan Cluett, MD Jonathan Cluett, MD LinkedIn Twitter Jonathan Cluett, MD, is a board-certified orthopedic surgeon with subspecialty training in sports medicine and arthroscopic surgery. Learn about our editorial process Updated on May 22, 2023 Medically reviewed by Amy Kwan, PT, DPT Medically reviewed by Amy Kwan, PT, DPT Amy Kwan, PT, is a physical therapist based in New York City who specializes in providing care to patients with a variety of orthopedic and neurological conditions. Learn about our Medical Expert Board Fact checked by Angela Underwood Fact checked by Angela Underwood LinkedIn Angela Underwood's extensive local, state, and federal healthcare and environmental news coverage includes 911 first-responder compensation policy to the Ciba-Geigy water contamination case in Toms River, NJ. Her additional health-related coverage includes death and dying, skin care, and autism spectrum disorder. Learn about our editorial process Print Table of Contents View All Table of Contents Overview Causes Symptoms and Diagnosis Treatment Prevention A nonunion occurs when a broken bone does not heal. Bones have a tremendous capacity for healing themselves, and with proper treatment, most all fractures will heal without complication. However, some fractured bones have difficulty healing. When a bone is slow to heal, we call this a "delayed union, and when a bone does not heal, we call this a"nonunion." Izabela Habur / E+ / Getty Images Overview Any broken bone can develop into a nonunion, but several bones are notorious for nonunion development. The reason is that the blood flow to these bones is poor even in normal daily life, and therefore, they are a 'set-up' for a nonunion. The problem broken bones for nonunion include: Scaphoid fractures Talus fractures Femoral neck fractures Fifth metatarsal ("Jones") fractures Causes Determining the cause of a nonunion is critical to determining the proper treatment. The most common causes of nonunion are: Infection: If bacteria enter the site of the break, it can prevent proper healing.Inadequate blood flow to the bone: Healing bones get many factors delivered by the blood supply, including the cells that repair the broken area, growth factors, and good old oxygen. Some bones have a limited blood supply and in other cases, the supply is disrupted by the injury.Separation of the fractured ends of the bone: The bones may not have been set close enough for a union, or may have separated after stabilization.Inadequate stabilization of the fracture: Stabilization is one of the key parts of treating broken bones. If the fracture wasn't able to be set properly, a nonunion might result. Sometimes a cast is not enough, and the fracture must be stabilized with screws, rods, plates, etc. Symptoms and Diagnosis If you continue to feel pain at the site of the break long after it has been set, you may suspect something is wrong and consult your healthcare provider. Nonunion can be diagnosed through x-rays, pain and immobility at fracture site, and time. Your healthcare provider might follow up at intervals to see if healing progresses over months. Treatment The treatment of a nonunion depends on the cause of the problem. Only once the cause of the nonunion is understood can proper treatment be initiated. Treatment may involve surgery to remove the infection, to better stabilize the fracture, or to stimulate bone growth with bone graft. If the cause is a lack of good stabilization, you may need internal fixation with metal plates, rods, and screws or bone grafting. External fixation with a rigid frame is used for some nonunions. Nonsurgical treatment might use a bone stimulator device that is used daily with ultrasonic or electromagnetic waves. Electric Stimulation for Fracture Healing Prevention The best thing a patient can do to prevent a nonunion is to avoid smoking. Other factors that will help prevent nonunions include eating well and adhering to your recommended treatment plan. Patients who are smokers, obese, have diabetes or have other medical conditions, may be at higher risk for developing a nonunion. 14 Sources Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. Ekegren CL, Edwards ER, De Steiger R, Gabbe BJ. Incidence, costs and predictors of non-union, delayed union and mal-union following long bone fracture. 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Early definitive internal fixation for infected nonunion of the lower limb. J Orthop Surg Res 16, 632 (2021). doi: 10.1186/s13018-021-02785-9 Simpson AHRW, Robiati L, Jalal MMK, Tsang STJ. Non-union: Indications for external fixation. Injury. 2019;50 Suppl 1:S73-S78. doi: 10.1016/j.injury.2019.03.053 Aleem, I., Aleem, I., Evaniew, N. et al. Efficacy of Electrical Stimulators for Bone Healing: A Meta-Analysis of Randomized Sham-Controlled Trials. Sci Rep 6, 31724 (2016). doi: 10.1038/srep31724 American Academy of Orthopaedic Surgeons. Nonunions. By Jonathan Cluett, MD Jonathan Cluett, MD, is board-certified in orthopedic surgery. He served as assistant team physician to Chivas USA (Major League Soccer) and the United States men's and women's national soccer teams. See Our Editorial Process Meet Our Medical Expert Board Share Feedback Was this page helpful? Thanks for your feedback! What is your feedback? Other Helpful Report an Error Submit