Method and apparatus for monitoring deviation of a limb

Apparatus for monitoring, measuring and/or estimating deviation of a body part of a vertebral mammal, said apparatus including:

• at least one sensor for measuring rotation of said body part relative to a first frame of reference and for providing data indicative of said rotation;
• a memory device adapted for storing said data;
• and
• a processor adapted for processing said data to evaluate a deviation of said body part that correlates to said data;
• wherein said processor is configured to execute an algorithm for evaluating said deviation of said body part, wherein said algorithm is adapted to:
• integrate said data over a period of time to provide an angular displacement (θ);
• evaluate a twist component (θX) of said angular displacement representing twist angle;
• and
• compensate said twist component (θX) by adding an angular offset (θx0) to said twist component (θX).