Patent · US Expired

Joint displacement measurement apparatus

US5435321A · kind A · utility

34Cited by
9References
23Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 10, 1993
Grant dateJul 25, 1995
Priority date
Expiry dateDec 10, 2013

Classification

  • Technology area (CPC A)Human Necessities
  • CPC primaryA61B5/6831
  • WIPO fieldMedical technology
  • WIPO sectorInstruments

Abstract

The measurement device includes a frame with a support and mounting member, a longitudinal bar, a lateral bar pivotally and slidably attached to the longitudinal bar with a pair of stirrups or heel cups attached symmetrically on either side of the longitudinal bar at a known distance from the longitudinal bar. A plurality of potentiometers or other resistive measurement devices are attached to the two bars to provide analog measurements of lengthwise and angular displacement. A microprocessor controller calculates actual leg length and offset by combining the measurements obtained from the first two resistive elements using a simple trigonometric function. An output means in the form of an LED and/or LCD display provides a visual display of the calculated actual and offset values.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.