Spinal cord simulation systems with patient activity monitoring and therapy adjustments

• US 6,440,090 B1
• Filed: 08/31/2000
• Issued: 08/27/2002
• Est. Priority Date: 04/30/1998
• Status: Expired due to Term

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Schallhorn, Rick
• Primary Examiner(s): Shaver, Kevin
• Assistant Examiner(s): SZMAL, BRIAN SCOTT
• Application Number:
  US09/652,741
• Time in Patent Office: 726 Days
• Field of Search: 600/595, 600/300, 607/46, 607/116, 607/30, 607/19, 607/32, 607/62, 607/60
• US Class Current: 600/595
• CPC Class Codes: A61N 1/36071 Pain

Abstract

A patient activity level recorder and a patient therapy adjustment recorder are provided to obtain an historical representation of patient activity levels and therapy changes in the form of profiles which are stored for later retrieval. The patient activity level profile and the therapy adjustment profile may be used to objectively interpreting subjective patient information. The activity level recorder may include an accelerometer, the output of which is processed by a signal processor, programmed to interpret the sensor raw signal as one of a plurality of predetermined activity levels. In a preferred embodiment, data for rest, moderate and vigorous activity levels for each day in a recording period are stored for later retrieval and use by a physician, or possible by the patient where therapy is self-administered. The therapy adjustment recorder may include a processor for interpreting signals from a patient control interface to a pulse generator of a spinal chord stimulation system.

Claims

1. A spinal cord stimulation system capable of obtaining objective patient data comprising:

a recorder for recording an historical representation of patient activity levels, the recorder including;

a sensor for generating signals corresponding to respective levels of patient activity;

a signal processor for generating a patient activity level profile from the signals, the patient activity level profile including a historical representation of activity levels in a plurality of predetermined categories of activity and the relative amounts of time that a patient has engaged in each of the categories of activity;

a storage for storing the patient activity level profile; and

a reporting interface for permitting a physician to retrieve the patient activity level profile;

whereby the retrieved patient activity level profile may be used by a physician to objectively interpret subjective patient information and determine whether the spinal cord stimulation is adequate or needs to be adjusted.

2. The system according to claim 1, wherein the signal processor is adapted to categorize one of the levels of patient activity by comparing a long-term average activity level and a short-term average activity level.

3. The system according to claim 1, wherein the predetermined categories include rest, moderate and vigorous activity levels.

4. The system according to claim 1, wherein the recorder further comprises a filter for filtering the signals.

5. The system according to claim 1, wherein the recorder further comprises a patient therapy adjustment recorder for recording a patient therapy adjustment profile representing historical adjustments of patient therapy.

6. The system according to claim 1, further comprising a patient control interface for permitting patient control of therapy.

7. A method of obtaining objective patient data in a spinal cord stimulation system comprising the steps of:

providing a recorder for recording an historical representation of patient activity levels;

recording a historical representation of patient activity levels as a patient activity level profile, including a plurality of predetermined categories of activity and the relative amounts of time that a patient has engaged in each of the categories of activity;

retrieving the historical representation; and

utilizing the historical representation to objectively interpret subjective patient information and determine whether the spinal cord stimulation is adequate or needs to be adjusted.

8. The method according to claim 7, wherein the step of providing a recorder comprises the steps of:

providing a sensor for generating signals representing respective levels of patient activity;

providing a signal processor for generating the patient activity level profile from the signals;

providing a storage for storing the patient activity level profile; and

providing a reporting interface enabling retrieval of the stored patient activity level profile from the storage.

9. The method according to claim 7, wherein the predetermined categories of activity comprise categories of rest, moderate and vigorous activity.

10. The method according to claim 7, wherein the step of recording an historical representation of patient activity levels further comprises the step of categorizing patient activity in one of the predetermined categories by comparing a long-term average activity level and a short-term average activity level.

11. The method according to claim 7, further comprising the step of providing a patient therapy adjustment recorder for recording a patient therapy adjustment profile representing historical adjustments of patient therapy.

12. The method according to claim 11, wherein the step of utilizing the historical representation further comprises the step of optimizing patient therapy based on the therapy adjustment profile.

13. The method according to claim 11, wherein the step of utilizing the historical representation further comprises the step of interviewing the patient to obtain the subjective information.

14. The method according to claim 11, wherein the step of utilizing the historical on comprises the step of choosing one of a plurality of therapy settings based on the presentation.

15. The method according to claim 11, wherein the step of providing a therapy adjustment recorder further comprises the step of providing a patient control interface for permitting patient control of therapy.