Physical Diagnostics, Inc.

Other

Orthopaedic Research Institute, Inc.

Paul C McLeod

A knee loading and testing apparatus has tibia and femur bone mounting units, respectively, and a quadricep loading means and unit for automatically manipulating the mounting means to the quadricep loading means to derive data regarding the knee joint. The quadricep is variably controlled to allow variation in the torque and pull and at the same time, both the femur and tibia mountings are independently articulatable, and further, these various loadings may be controlled and recorded by a computer and the response to the joint to various loadings may be recorded for future study and analysis by any computer. Preset limits on the application of the quadricep force and body weight are provided and the operator is provided with a visual and audible signal indicating the overload. The machine also disables the control from further increasing these load functions and while the controls for decreasing this loading remain operable. Either drive may be released for the transverse or coronal plane motions while still measuring the angulation of the tibia in both planes. The knee specimen can be rotated about an axis through the hip and ankle, so that viewing, surgical procedures and x-raying may be performed with the specimen in place thus eliminating removal and/or installation errors from the data. The machine uses the quadricep force applied through patella thereby providing for simulation of abnormal patello-femural interaction by providing a wide range of 'Q' angle variations, injuries, diseases, abnormalities associated with this particular surface can be studied.

Knee loading and testing apparatus and method

A three-plane goniometer or angle measuring apparatus includes three small potentiometers which are closely spaced together to measure rotation of the knee about three different axes. The unit is primarily mounted on a cuff on the outside of the thigh. The mounting assembly for the three plane goniometer includes a curved yoke where the ends of the yoke curve from the front to the rear, with the goniometer unit being held between the ends of the rearwardly extending arms of the yoke, so that accurate measurement may be maintained in all three planes even while the knee is bent to its extreme flexed position. Extending downwardly from the goniometer is a square rod which slidably engages a square hole in a nylon ball mounted in a two-axis gimbal, which is secured to a cuff strapped to the calf of the leg. Injuries may be diagnosed or characterized by comparing the pattern for one leg before injury with the pattern for that leg after injury or by comparing the pattern for one (healthy) leg with that for the other (injury) leg. The goniometer is mounted so that it may be readily reversed and used for both the right and left legs. Associated processing circuitry includes corresponding reversing circuits for conforming the plots for the right and left leg, and also includes special face marking circuitry. Comparative tests may be made for different types of footwear and athletic playing surfaces, and the torque which is produced may be compared to determine the preferred foot gear or playing surface.

Dynamic joint motion analysis technique

A three-plane goniometer or angle measuring apparatus includes three small potentiometers which are closely spaced together to measure rotation of the knee about three different axes. The unit is primarily mounted on a cuff on the outside of the thigh. The mounting assembly for the three plane goniometer includes a curved yoke where the ends of the yoke curve from the front to the rear, with the goniometer unit being held between the ends of the rearwardly extending arms of the yoke, so that accurate measurement may be maintained in all three planes even while the knee is bent to its extreme flexed position. Extending downwardly from the goniometer is a square rod which slidably engages a square hole in a nylon ball mounted in a two-axis gimbal, which is secured to a cuff strapped to the calf of the leg. Injuries may be diagnosed or characterized by comparing the pattern for one leg before injury with the pattern for that leg after injury or by comparing the pattern for one (healthy) leg with that for the other (injured) leg. The goniometer is mounted so that it may be readily reversed and used for both the right and left legs. Associated processing circuitry includes corresponding reversing circuits for conforming the plots for the right and left leg, and also includes special face marking circuitry. Comparative tests may be made for different types of footwear and athletic playing surfaces, and the torque which is produced may be compared to determine the preferred foot gear or playing surface.

Growing community of inventors

Little Rock, AR, United States of America

Paul C McLeod