Background:

Currently, surgeons will take approximately six x-rays of a patient's spine during both a pre-operative visit, as well as, at least three post-operation visits in order to determine spinal motion. These x-rays are not cost efficient for the patient, as the total is about $2000 per visit. The exposure to radiation is also harmful for the patient, as it is 60 mrem per x-ray. Each x-ray taken is time consuming and requires the patient to stand still while the series of x-rays are taken during each visit. Alternative apparatus and techniques for measuring spinal motion without the use of x-rays are therefore desirable.

Summary:

This invention features a device for measuring movement of a body having a first point that is moveable relative to a second point and includes a plurality of mechanically coupled articulable elements capable of rotating relative to one another, establishing a plurality of axes of rotation and defining an articulable assembly. A sensor is coupled to at least one of the articulable elements and is capable of sensing rotation thereof relative to an adjacent articulable element and generating a first signal representative of the angle of rotation. A computer communicatively coupled to the sensor can receive a signal corresponding to the first signal and storing the angle of rotation. A first end of the articulable assembly can couple proximate the first point on the body. A second end of the articulable assembly can couple proximate to the second point on the body.

There are 3 axes used here which intersect each other and a rotation of any articulable element on theses axes is independent of rotation of other articulable elements. There is a sensor, which is a potentiometer, dedicated to each of the axes to monitor rotation about them. The potentiometers each have a stem rotatable relative to a housing thereof, the potentiometers forming the mechanical link between adjacent elements in the articulable assembly upon which the adjacent elements pivot, with the stem attached to a first of the adjacent elements and the housing attached to a second of the adjacent elements, the potentiometers capable of generating the first signal when rotated.

The device includes an interpreter which receives the first signal, converts it to a digital signal and conveying the digital signal to the computer where the signal is converted into rotational angle data and then its communicated to user. The angle data stored in the computer is obtained over a period of time at a given sampling rate, such that multiple angle data values are generated and stored when the body executes a motion from a first position to a second. The interpreter includes a Wheat stone bridge for determining a resistance value of the potentiometer at a given rotational position of the potentiometer.

The device includes a first extension with a first end coupled to the first end of the articulable assembly and a second end capable of being coupled to the body proximate the first point and a second extension with a first end coupled to the second end of the articulable assembly and a second end capable of being coupled to the body proximate the second point. The device includes a wireless connection between the device and the computer. The computer is connected to the Internet and is capable of communication the signal data to a remote computer. The device includes a phone interface through which the angle data may be communicated to another over a wireless network. In another embodiment, the articulable assembly includes a U-shaped flange, two L-shaped flanges and a coupling inter mediating there between, a first potentiometer attached to a first arm of the U shape by the housing thereof with the stem thereof extending toward and being mechanically coupled to a first arm a first of the L-shaped flanges, a second potentiometer attached a second arm of the first L-shaped flange with the stem thereof extending toward and mechanically coupled to the coupling, a third potentiometer attached to a first arm of the second L-shaped flange with the stem thereof extending toward and mechanically coupled to the coupling at right angles to the stem of the second potentiometer, the first end of the first extension attached to the U-shaped flange at a second arm opposite to the first potentiometer and the first end of the second extension attached to the second L-shaped flange on a second arm of the second L-shaped flange, the second ends of the first and second extensions capable of being coupled to a harness worn on the body. In another embodiment, a method of measuring the movement of an articulable anatomy moveable from a first position to a second position, includes the steps of:

(A) obtaining a goniometer with an articulable assembly having a plurality of articulable elements rotatable about a plurality of intersecting axes and sensors capable of generating signals representative of the rotation of the articulable elements about the axes

(B) coupling the goniometer to the anatomy, with the goniometer bridging from a first point on the anatomy to a second point on the anatomy, such that when the anatomy moves, the first point moves relative to the second point and moves the articulable elements in a manner corresponding to the movement of the anatomy, the sensors generating virtually simultaneous, independent signals corresponding to each rotational movement of the articulable elements; converting the independent signals into angle data representing the magnitude of rotation sensed by each sensor and; recording the angle data for a plurality of movement states from a start position of the anatomy to an end position.

Applications:

- Eliminates the need for multiple X-Rays which are expensive to the patient

Full Patent: Tri-Axial Electro-Goniometer For Spinal Motion