Monitorable bone growth stimulator
US4414979A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 23, 1981 |
| Grant date | Nov 15, 1983 |
| Priority date | — |
| Expiry date | Feb 23, 2001 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61N1/205
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
There is disclosed an implantable bone growth stimulator whose direct-current output can be monitored. Rather than to interrogate the device, e.g., by using a control magnet as in the heart pacer art, the device continuously transmits pulses of electromagnetic energy at a rate proportional to the current being delivered. The continuous transmission expends no more than about five percent of the total power. Instead of using an electrode lead as an antenna for radiating the pulses, a separate coil inside the device is utilized so that the therapeutic current itself is in no way affected by the pulse transmission. Effective transmission is achieved despite the fact that the device is hermetically sealed in a titanium case. Also included is an electronic switch for drastically limiting power drawn from the battery until implantation takes place, in order to provide an extended shelf life.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.