If your broken bone has not healed after three or more months, your doctor may recommend bone growth stimulation therapy to promote bone growth in either your hard-to-heal ("nonunion") or slow-healing ("delayed union") fractures. This can occur in cases of severe trauma, but other risks for slow-healing bones include advanced age, obesity, smoking, diabetes, arthritis, renal disease and infection at the fracture site.
Types of Stimulators
Your doctor may recommend a bone growth stimulator that is applied to your fracture either from the inside of your body (invasive) or from the outside of your body (noninvasive). If surgery is a low-risk option for you, an invasive bone growth stimulator device and battery can be partially or fully implanted at your fracture site. According to Aetna.com the fully implanted device provides direct electric current to the fracture 24 hours a day and requires little daily attention from you; it has no known side effects. Once stimulation the fracture has healed, your bone growth device and battery will be surgically removed.
In situations where surgery presents significant risks, if you don't want surgery, or if other attempts to heal your fracture have failed, noninvasive bone growth treatment may be the better option. According to Orthofix.com the most common noninvasive stimulator is composed of external coils placed on either side of the fracture and held in position by a strap or cuff. You use the device to stimulate the fractured area anywhere from three to 10 hours each day for at least one hour at a time. You can use the device over your cast, orthopaedic brace or clothing and wear it comfortably during daily activities.
Ultrasound stimulation is the latest noninvasive treatment for stimulating bone growth. This device needs to be applied to your fracture site for as little as 20 to 30 minutes each day.
How They Work
All types of bone growth stimulator devices have been found to be effective in 80 to 90 per cent of properly selected patients, according to Aetna.com. These treatments stimulate the growth of blood vessels at the fracture site as well as osteoblasts, bone-forming cells that a form a fibrocartilage bridge across the fracture site. By encouraging this fibrocartilage to turn to bone, a bone growth stimulator quickly rebuilds your bone at the point of fracture.
The specific type of bone healing system used in your situation depends on the type and location of your fracture. Treatment and healing time may range anywhere from three to six months, but rarely longer than nine months.
Bone growth stimulation cannot be used if the gap between the ends of your fracture is too large. It is also not advised if you use a pacemaker or are pregnant, and it is not usually used in children, whose skeletons are still immature. If you have fractured your pelvis, scapula, skull, ribs or sternum, stimulation therapy is less likely to be used.