How are nonunions treated?
Nonsurgical and surgical treatments for nonunions have advantages and disadvantages. More than one alternative may be appropriate. Discuss with your provider the unique benefits and risks of treating your nonunion. Your doctor will recommend the treatment option that is right for you.
Some nonunions can be treated without surgery. The most common nonsurgical treatment is a bone stimulator. This small device delivers ultrasonic or pulsed electromagnetic waves that stimulate healing. The patient places the stimulator on the skin over the nonunion from 20 minutes to several hours daily. This treatment must be used every day to be effective.
Surgery is needed when nonsurgical methods fail. You may also need a second surgery if the first surgery failed. Surgical options include bone graft or bone graft substitute, internal fixation, and/or external fixation.
Bone Graft. During this procedure, bone from another part of the body at the fracture site to "jump start" the healing process. A bone graft provides a scaffold on which new bone may grow. Bone grafts also provide fresh bone cells and the naturally occurring chemicals the body needs for bone healing.
During the procedure, a surgeon makes an incision and removes (harvests) pieces of bone from different areas on the patient. These are then transplanted to the nonunion site. The rim of the pelvis or "iliac crest" is most often used for harvesting bone. Although harvesting the bone may be painful, the amount of bone removed usually does not cause functional, structural, or cosmetic problems.
Allograft (cadaver bone graft). An allograft (cadaver) bone graft avoids harvesting bone from the patient, and therefore, decreases the pain involved with treating the nonunion. Like a traditional bone graft, it provides scaffolding for the patient's bone to heal across the area of the nonunion. As time goes on, the patient's bone replaces the cadaver bone. Although there is a theoretical risk of infection, the cadaver bone graft is processed and sterilized to minimize this risk.
Bone graft substitutes and/or osteobiologics. As with allografts, bone graft substitutes avoid the bone harvesting procedure and related pain. Although bone graft substitutes do not provide the fresh bone cells needed for normal healing, they do provide a scaffold chemicals needed for growth.
Depending on the type of nonunion, any of the above materials, or a combination of materials, may be used to fix the nonunion. Bone grafts (or bone graft substitutes) alone provide no stability to the fracture site. Unless the nonunion is inherently stable, you may also need more surgical procedures (internal or external fixation) to improve stability.
Internal Fixation. Internal fixation stabilizes a nonunion. The surgeon attaches metal plates and screws to the outside of the bone or places a nail (rod) in the inside canal of the bone. If a nonunion occurs after internal fixation surgery, another internal fixation surgery may be needed to increase stability. The surgeon may use a more rigid device, such as a larger rod (nail) or a longer plate. Removing a previously inserted nail and inserting a larger one (exchange nailing) increases stability and stimulates healing within the bone. Internal fixation can be combined with bone grafting to help stability and stimulate healing.
External fixation. External fixation stabilizes the injured bone, as well. The surgeon attaches a rigid frame to the outside of the injured arm or leg. The frame is attached to the bone with wires or pins. External fixation may be used to increase the stability of the fracture site if instability helped cause the nonunion. External fixation can treat nonunions in a patient who also has bone loss and/or infection.