Apparatus and method for monitoring bone-fracture union
US4649933A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 12, 1984 |
| Grant date | Mar 17, 1987 |
| Priority date | — |
| Expiry date | Sep 12, 2004 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61F13/041
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A system for monitoring bone union at a bone fracture (13) comprises a fracture cast sleeve (15) to the external surface of which is bonded a transducer (16). Transducer (16) is electrically-conductive and has an electrical resistance which varies with elastic extension and contraction of the transducer. The output of transducer (16) is applied via a resistance-sensitive network (18) to a data evaluating device (20) arranged to normalize signals received from transducer (16) with respect to the time interval during which that signal appears since the signal is of an impulse nature depending upon the rate at which the force is applied to the fracture (13). The normalized signal is further normalized having regard to the mass of the limb concerned and a plurality of such signals are stored in store (30) together with a data log from date data device (32) and these signals are fed to a trend evaluator (34) in order to predict the time interval before bone union occurs.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.