Development of a microcomputer-based system to monitor healing from injury.
It is well documented that induction of electric current in bone not only prevents the bone loss of functional disuse, but also induces new bone formation. Moreover, the literature suggests that the skeletal response is optimal at a distinct frequency range 10-30 Hz. Indeed, even at peak strains, well below those typical of habitual physiological loading, applications of 30 Hz were shown to be osteogenic. This evidence supports the concept that inducing even very low strains may generate an effective osteogenic stimulus, provided that they are induced at optimal frequency (10 to 30 Hz). Bone appears to respond with greater selectivity and sensitivity to this frequency range of electrical stimulation. Inducing insulin-like growth factors, which are negatively charged, will provide the required electrical stimulus. Traditionally, the progression of the cellular events during trauma is normally followed by x-ray to determine a healing rate. Frequent use of this method can result in serious side effects to the vital and reproductive organs. The objective of this study is to develop a microcomputer-based system to monitor the cellular events associated with healing. The system is capable of transmitting an electrical signal directly to the site of injury to improve the healing process and to monitor the progress of osteogenesis. The system consists of a base unit and implanted units. One implanted unit will be inserted in the femur with induced trauma and the other implant will be in the control femur. The base unit will transmit low frequency electromagnetic waves to the implanted units as well as receive periodic information about the ion movement in both femurs.