Patent ID: 6890312

Claim:
A joint angle indication system for providing information related to an angular relationship between a first body part and a second body part which are pivotally coupled at a joint, the system comprising: a first arm member operable for attachment to the first body part, the first arm member having a first proximal end and a first distal end; a second arm member operable for attachment to the second body part, the second arm member having a second proximal end and a second distal end, the second proximal end of the second arm member pivotally coupled to the first proximal end of the first arm member; at least one joint angle variation sensor for providing at least one electrical characteristic which varies based on variation in a joint angle of the first arm member relative to the second arm member, where the joint angle is variable over an angular range which includes a first angle and a second angle, the at least one joint angle variation sensor comprising first and second potentiometers coupled between the first and second arm members for providing a first electrical resistance of the first potentiometer and a second electrical resistance of the second potentiometer; a biofeedback circuit operable to generate a first feedback signal when the first electrical resistance of the first potentiometer indicates the joint angle is less than or equal to the first angle, operable to generate the second feedback signal when the first electrical resistance of the first potentiometer indicates the joint angle is greater than or equal to the second angle, and operable to generate no feedback signal when the first electrical resistance of the first potentiometer indicates the joint angle is less than the second angle and greater than the first angle; and an angle display circuit for visually displaying a joint angle value based on at least the second electrical resistance.