Arthrometer with gravity switches and adjustable limit signaling
First Claim
1. An arthrometer assembly for monitoring an angle of flexure of an elongated body limb relative to the portion of the body to which the limb is attached, the assembly comprising:
- A. a rigid housing extending along a principal axis, and including;
i. a first gravity-activated switch having an associated first switch axis, said first switch having at least two states and being responsive to its spatial orientation whereby said first switch changes between its first and second states when a first switch axis angle changes between a value greater than a first predetermined switch angle and a value less than said first predetermined switch angle, said first switch axis angle being the angle of said first switch axis measured with respect to a vertical axis,ii. first vernier means for adjustably controlling the orientation of said first switch axis with respect to said principal axis with a sensitivity reduction greater than 1;
1,iii. means for selecting said first predetermined switch angle, andiv. means for generating a signal representative of changes in state of said first switch;
B. means for coupling said housing to the limb so that said principle axis is at a fixed orientation with respect to the limb.
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Accused Products
Abstract
An apparatus for measuring the angle of flexure between an elongated body limb and the portion of the body to which the limb is affected. The apparatus can be used to monitor flexure between a thigh and lower portion of a human leg. The apparatus is useful during the performance of rehabilitative knee-bends includes means for coupling the apparatus to the thigh, and two gravity actuated switches for monitoring the angle between a long axis of the thigh and vertical axis. The apparatus indicates when the extreme points of the knee-bend have been crossed.
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Citations
20 Claims
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1. An arthrometer assembly for monitoring an angle of flexure of an elongated body limb relative to the portion of the body to which the limb is attached, the assembly comprising:
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A. a rigid housing extending along a principal axis, and including; i. a first gravity-activated switch having an associated first switch axis, said first switch having at least two states and being responsive to its spatial orientation whereby said first switch changes between its first and second states when a first switch axis angle changes between a value greater than a first predetermined switch angle and a value less than said first predetermined switch angle, said first switch axis angle being the angle of said first switch axis measured with respect to a vertical axis, ii. first vernier means for adjustably controlling the orientation of said first switch axis with respect to said principal axis with a sensitivity reduction greater than 1;
1,iii. means for selecting said first predetermined switch angle, and iv. means for generating a signal representative of changes in state of said first switch; B. means for coupling said housing to the limb so that said principle axis is at a fixed orientation with respect to the limb. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18)
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19. An arthrometer for monitoring an angle of flexure of an elongated body limb with respect to the portion of the body to which the limb is attached, comprising:
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A. an elongated housing extending along a principal axis, B. means for detachably coupling said housing to the limb whereby said principal axis is at a fixed orientation with respect to a central axis of the limb, C. first limit sensor affixed to said housing including; i. a first gravity-actuated switch coupled to said housing and responsive to orientation relative to a vertical axis, so that said first switch is in a first state when said first switch is oriented within a first range of orientations, and said first switch is in a second state when said first switch is oriented within a second range of orientations, ii. first switch positioning assembly including first vernier means for adjustably orienting said first switch with respect to said principal axis with a sensitivity reduction greater than 1;
1, whereby said first switch is in its first state when said principal axis is oriented within a first predetermined range of orientations measured with respect to the vertical axis and in its second state otherwise, andD. second limit sensor affixed to said housing including; i. a second gravity-actuated switch coupled to said housing and responsive to orientation relative to the vertical axis, so that said second switch is in a first state when said second switch is oriented within a third range of orientations, and said second switch is in a second state when said second switch is oriented within a fourth range of orientations, and ii. second switch positioning assembly including second vernier means for adjustably orienting said second switch with respect to said principal axis with a sensitivity reduction greater than 1;
1, whereby said second switch is in its first state when said principal axis is oriented within a second predetermined range of orientations measured with respect to the vertical axis and in its second state otherwise.
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20. An arthrometer assembly for monitoring an angle of flexure of an elongated body limb relative to the portion of the body to which the limb is attached, the assembly comprising:
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a rigid housing having a principal axis, means for coupling said housing to the limb of a patient so that said principal axis is at a fixed orientation with respect to a central axis of the limb, a gravity-actuated sensor having an output indicative of an angle between said sensor and a vertical axis, vernier means for angularly orienting said sensor with respect to said principal axis with a sensitivity reduction greater than 1;
1, andmeans for monitoring said sensor output.
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Specification