Electric bone stimulation is a medical technique that promotes bone healing, especially when natural processes are insufficient. It involves applying controlled electrical currents to a specific bone area, stimulating cellular activity and enhancing the body’s natural repair mechanisms.
How Electric Bone Stimulation Works
The scientific basis of electric bone stimulation lies in how electrical currents interact with bone cells and the surrounding environment. Bone tissue exhibits a phenomenon called piezoelectricity, meaning it generates small electrical potentials when subjected to mechanical stress, such as walking or exercising. This natural electrical activity plays a role in regulating bone remodeling, which is the continuous process of old bone being removed and new bone being formed.
Electrical stimulation influences this balance by affecting specialized bone cells. Osteoblasts build new bone tissue, while osteoclasts break down old bone. When electrical signals are introduced, they enhance osteoblast activity, promoting the synthesis of proteins like collagen and encouraging calcium deposition, both building blocks for new bone. Electrical stimulation can also increase intracellular calcium ion concentration, triggering biochemical reactions that promote cell proliferation and differentiation, ultimately leading to accelerated bone formation.
Medical Conditions Treated
Electric bone stimulation is primarily used for conditions where bones struggle to heal on their own. A common application is for non-union fractures, which are breaks that have failed to show progressive healing signs after at least nine months following the injury. It is also employed for delayed union fractures, where healing is progressing but at a slower than expected rate.
This therapy is also frequently used as an adjunct to spinal fusion surgeries. In these procedures, electric stimulation helps promote successful bone growth between vertebrae, increasing the likelihood of a solid fusion. Beyond fractures and spinal fusions, it may also be considered for other bone defects where enhanced bone formation is desired.
Types of Electric Bone Stimulation Devices
Electric bone stimulation devices fall into two main categories: non-invasive and invasive. Non-invasive devices are worn externally and deliver electrical signals without requiring surgery. These include pulsed electromagnetic fields (PEMF), which use coils placed over the skin to generate a time-varying magnetic field that induces an electric field in the tissue.
Capacitive coupling (CC) devices are another non-invasive option, using skin pads or electrodes placed on opposite sides of the bone to create an electric field. Direct current (DC) stimulation is an invasive method, involving surgically implanted electrodes directly into the bone. These implanted devices provide continuous stimulation directly at the site of healing, though they carry the risks associated with surgical procedures.
Undergoing Electric Bone Stimulation Treatment
Patients undergoing electric bone stimulation treatment can expect a routine that varies based on the device type. Non-invasive devices, such as those using pulsed electromagnetic fields or capacitive coupling, are worn for several hours a day, usually for 3 to 9 months. These devices are portable and can be worn over a cast or brace, allowing patients to continue daily activities.
Surgically implanted devices provide continuous stimulation and remain in place for six to nine months until healing is complete. While some patients report no sensation, others might experience a mild tingling or warmth at the site of stimulation. This treatment is used in conjunction with other therapies like casts, internal fixation, or bone grafting, to support bone healing.