A method of detecting disorders in a foot of a diabetic subject, wherein a selected subject may experience a loss of sensation in one or both of the selected subject's feet due to the selected subject being a diabetic, the method comprising:
- (a) fitting the selected subject with a first and a second footwear fitted for a selected subject's first and second foot, respectively, wherein the fitting of both the first and the second footwear include:
- (1) placing a 3-axis accelerometer within the first and second footwear;
- (2) placing a 3-axis gyroscope within the first and the second footwear;
- (3) placing a 3-axis magnetometer within the first and the second footwear;
- (4) placing a plurality of force sensors under the selected subject's feet generating associated and corresponding force vectors, and wherein a shear force is applied to both the first and the second foot, and wherein the force vectors and the shear forces are collectively referred to as force information;
- (5) placing a plurality of temperature sensors measuring skin temperature and generating foot temperature information for both of the selected subject's feet;
- (6) placing haptic actuators under the big toe of the selected subject's first and second foot;
- (7) providing a control microprocessor;
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- (8) providing a motion processing element, wherein the motion processing element obtains samples of sensor data during selected sampling periods from the accelerometers, the gyroscopes, the magnetometers, the plurality of force sensors and the plurality of temperature sensors,
- and wherein, at the end of the selected sampling periods, the motion processing element generates motion information including g-force, acceleration information, Euler Angles, Quaternion information and the force vectors;
- (b) analyzing the information generated by the first and the second footwear by performing the following:
- (1) using the motion information, obtaining a natural pronation of the selected subject's feet;
- (2) using the motion information, the force information, and the selected subject's physical characteristics, computing a distribution of ground reaction force (GRF) for each of the selected subject's feet, and determining a shear force safety threshold by computing vertical and horizontal components of the GRF for each of the selected subject's feet;
- (3) using the temperature information:
- a. determining a normalized temperature for each of the selected subject's feet;
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- b. determining normalized temperature safety thresholds based upon a correlation of temperature information between similar locations of the selected subject's feet;
- (4) determining a vibratory perception threshold (VPT) indicating the selected subject's feet neuropathy level, and adjusting the temperature safety thresholds depending on the VPT of the selected subject's feet;
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- (5) determining the shear force applied to each of the selected subject's feet based upon the force information and the GRF for each of the selected subject's feet, and modifying the temperature safety thresholds and the shear force safety thresholds depending on the selected subject's activity;
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- (c) continuously monitoring the motion information generated by the motion processing element, the GRF, and the foot temperature information to determine variations in the foot temperature information and the shear forces;
- and comparing variations in the foot temperature information and the shear forces to the foot temperature and the shear force safety thresholds, and wherein if any of the safety thresholds are exceeded, generating a warning alert.