06044297 is referenced by 395 patents and cites 15 patents.

A method of and apparatus for determining the physical posture of a patient's body, having a superior-inferior body axis, an anterior-posterior body axis and a lateral-medial body axis, in relation to earth's gravitational field. A medical device having first, second and, optionally, third accelerometers having sensitive axes mounted orthogonally within an implantable housing is adapted to be implanted with the sensitive axes nominally aligned with ideal X, Y and Z device axes correlated to patient body axes. Each accelerometer generates DC accelerometer signals having characteristic magnitudes and polarities on alignment of the sensitive axis with, against or normal to earth's gravitational field and DC accelerometer signals of varying magnitudes and polarities when not so aligned. The actual pitch and roll angles of the sensitive axes of the accelerometers in the implanted IMD with respect to the true gravitational axes are determined and the yaw angles are determined or estimated. Corrected DC accelerometer output signals are derived from the pitch, roll and yaw angles and are compared to a set of stored thresholds for each body posture to determine the actual body posture. Storage of these comparisons or the raw signals themselves can be used for histogram data to provide theraputic or research benefits also described.

Title
Posture and device orientation and calibration for implantable medical devices
Application Number
9/160647
Publication Number
6044297
Application Date
September 25, 1998
Publication Date
March 28, 2000
Inventor
Can Cinbis
Shoreview
MN, US
Mark K Erickson
Brooklyn Park
MN, US
William J Combs
Eden Prarie
MN, US
Todd J Sheldon
North Oaks
MN, US
Agent
Reed A Duthler
Harold R Patton
Assignee
Medtronic
MN, US
IPC
A61N 1/362
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