Implantable displacement sensor means

• US 4,813,435 A
• Filed: 04/25/1988
• Issued: 03/21/1989
• Est. Priority Date: 04/25/1988
• Status: Expired due to Term

• Current Assignee: MicroStrain, Inc. (Spectris PLC)
• Original Assignee: Micro Strain Company
• Inventors: Arms, Steven W.
• Primary Examiner(s): Hindenburg, Max
• Assistant Examiner(s): Getzow, Scott M.
• Application Number:
  US07/185,918
• Time in Patent Office: 330 Days
• Field of Search: 310/338, 324/207, 128/774, 128/782, 73/779, 73/768, 73/DIG. 3, 73/DIG. 4
• US Class Current: 600/587
• CPC Class Codes: A61B 2562/0223 Magnetic field sensors
• CPC Class Codes: A61B 5/1107 Measuring contraction of parts of the body, e.g. organ, muscle apparatus for measuring work or force in general G01L
• CPC Class Codes: A61B 5/4523 Tendons
• CPC Class Codes: A61B 5/4533 Ligaments
• CPC Class Codes: A61B 5/6882 Anchoring means
• CPC Class Codes: G01B 7/16 for measuring the deformation in a solid, e.g. by resistance strain gauge

Abstract

This device is adapted for replacable implantation in soft body tissue for the measurement of the mechanical behavior of the soft tissues of the body. The device consists of an hall-effect strain transducer that detects the linear motion of a magnetic core. A barb force transducer uses a barbed probe that is inserted into the soft tissue. The barb force transducer has pressure sensors located within the body of the probe that detect the squeezing of the tissue fibers against the sides of the transducer. The combination of the hall-effect strain transducer and the barb force transducer allows the operator to simultaneously measure the strain and force on a specific soft tissue.

Claims

1. An implantable displaceable sensor means, for measuring the mechanical behavior of the soft tissue of the body, comprising:

at least one support base;

said support base has a horizontal aperture located therein;

electrical measuring means on said support base for determining linear motion;

magnetic means;

said magnetic means being located slidably within said horizontal aperture;

said electrical means has transmission means attached;

said support means has anchoring means;

said support means has a plurality of vertical apertures;

said anchoring means comprises at least one barbed extension;

said barbed extension has pressure sensing means located within said barbed extension; and

said pressure sensing means has information sensing means.

2. An implantable displacement sensor means, according to claim 1, wherein:

said support base comprises two separate units; and

said support base has flattened upper and lower surfaces.

3. An implantable displacement sensor means, according to claim 1, wherein:

said electrical measuring means comprises a hall-effect generator and said magnetic means.

4. An implantable displacement sensor means, according to claim 1, wherein:

said magnetic means comprises a sliding core to which a magnet is attached; and

said sliding core is connected to one part of said support base and inserted into said horizontal aperture of the other side of said support base.

5. An implantable displacement sensor means, according to claim 1, wherein:

said transmission means has protection means; and

said protection means comprises flexible tubing.

6. An implantable displacement sensor means, according to claim 1, wherein:

said barbed extension has hook means located on the end opposite the barbed end of said extension for maintaining pressure on said support base and for providing tieing means for a suture.

7. An implantable displacement sensor means, according to claim 1, wherein:

said barbed extension has a hollowed center section for permitting insertion of said pressure sensing means; and

said pressure sensing means comprises piezo electric materials.