It has been known for quite some time that bone growth is stimulated by DC electrical currents. However, only relatively recently implantable stimulators have been developed for the application.
In 1988 Biomet acquired Electrobiology Inc. (EBI) in Parsippany, NJ, a leader in bone-growth electrical stimulation and bone external fixation markets.
EBI’s OsteoGen™ Bone Growth Stimulator is marketed by Biomet Inc. It is designed for adjunctive use in the treatment of nonunions when surgery is required or when patient compliance is expected to be inadequate. The device is appropriate for any form of fracture. It is most often used on long bones and the clavicle. Variations of the OsteoGen device are available for high-risk fractures (OsteoGen™ Dual Lead Bone Growth Stimulator) and with mesh cathodes designed to provide scaffolding (OsteoGen™-M Bone Growth Stimulator).
Surgical implantation can involve coiling the electric wire and placing it inside the fracture or drilling holes into the bone and weaving the wire into the bone. Special techniques have been devised for integrating the wires with different bone graft materials and fixation products. The generator is placed subcutaneously 8 to 10 cm from the wire and, if necessary, is sutured to soft tissue. Typically, bone growth is stimulated by passing approximately 20μA of direct electrical current to the fracture site (cathode connected to the bone referenced to the can anode).
In addition, Biomet also markets two implantable electrical stimulators for use in spinal fusion: the SpF®-XL IIb Spinal Fusion Stimulator; and the SpF® PLUS-Mini Spinal Fusion Stimulator.
Company website: www.biomet.com
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