Patent ID: 6221033
Filing Date: 2001-04-24
Classification: A61H

Abstract:
A therapeutic device for use in providing physical therapy for a patient's knee, which device comprises:(a) an elongated frame having an axis;(b) a lower leg support having a first end and a second end and being adapted to support the lower leg of the patient;(c) an upper leg support having a first end and a second end and being adapted to support the upper leg of the patient;wherein the first end of the upper leg support is pivotally connected to the first end of the lower leg support so that said upper leg support and said lower leg support pivot with respect to each other through a plurality of pivotal positions, each of which establishes an angle between said upper leg support and said lower leg support; andwherein said frame, lower leg support and upper leg support are interconnected in a manner such that both the tibia and the femur of the patient are generally coplanar with the axis of the frame;said therapeutic device further including:(d) means for repeatedly pivoting the lower leg support and the upper leg support at the connection therebetween so as to move the patient's leg through a plurality of cycles of motion, each of which:(1) imposes a range of motion on the patient's leg comprising a flexion phase, in which the angles of the pivotal positions between the lower leg support and the upper leg support are decreasing, and an extension phase, in which the angles of the pivotal positions between the lower leg support and the upper leg support are increasing;(2) is defined by a flexion limit which establishes the minimum angle between the lower leg support and the upper leg support to which the lower leg support and the upper leg support are pivoted during a flexion phase and an extension limit which establishes the maximum angle between the lower leg support and the upper leg support to which the lower leg support and the upper leg support are pivoted during an extension phase;(e) means for setting a desired range of motion including:(1) an operational extension limit which corresponds to an operational extension angle between the upper leg support and the lower leg support to which the upper and lower leg supports are pivoted during the extension phase of a cycle; and(2) an operational flexion limit which corresponds to an operational flexion angle between the upper leg support and the lower leg support to which the upper and lower leg supports are pivoted during the flexion phase of a cycle;(f) means for setting at least one intermediate angle within the desired range of motion, which corresponds to a critical angle between the upper leg support and the lower leg support, wherein each such intermediate angle:(1) will correspond to a critical extension angle between the upper leg support and the lower leg support which is less than the operational extension angle; or(2) will correspond to a critical flexion angle between the upper leg support and the lower leg support which is greater than the operational flexion angle; and(g) means for setting a first rate at which the lower leg support and the upper leg support are pivoted at the connection therebetween;(h) means for setting a second rate at which the lower leg support and the upper leg support are pivoted at the connection therebetween;(i) means for changing the rate at which the lower leg support and the upper leg support are pivoted at the connection therebetween from the first rate to the second rate at the intermediate angle:(1) during the extension phase if the intermediate angle is a critical extension angle; or(2) during the flexion phase if the intermediate angle is a critical flexion angle;(j) means for changing the rate at which the lower leg support and the upper leg support are pivoted at the connection therebetween from the second rate to the first rate:(1) at the operational extension limit if the rate is changed from the first rate to the second rate during the extension phase; or(2) at the operational flexion limit if the rate is changed from the first rate to the second rate during the flexion phase.