JP2000201906A - Hand-held type ligament damage degree measuring device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To quantitatively diagnose the damge degree and cured degree of a ligament. SOLUTION: This device comprises a load transmission shaft 2 serving as a load transmission member, in which a displacement quantity imparting direction is the longitudinal direction of columnar shape, connected to a probe 1 imparting the displacement quantity in an orthogonal direction to the longitudinal direction of a ligament; X-axis, Y-axis, Z-axis direction load detecting parts 31, 32, 33 for detecting X-axis, Y-axis and Z-axis direction load applied to the load transmission shaft 2; an inner cylinder 4 integrally jointed to the load transmission shaft 2; an outer cylinder 5 serving as a cylindrical member holding the inner cylinder 4 slidably and having a grip part gripped by a measurer; and a displacement quantity regulating means 6 for regulating the displacement quantity of the inner cylinder 4 moving in the outer cylinder 5. The specified displacement quantity is therefore imparted to the ligament, and reaction generated at that time can be detected as each load in the X-axis, Y-axis and Z-axis directions.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of controlling a displacement of a load transmitting member to apply a prescribed displacement to the ligament via a probe, and to detect a reaction force generated at that time by a triaxial load detector. The present invention relates to a hand-held ligament damage measuring device for quantitatively determining the degree of damage to a ligament based on the loads in the X-axis, Y-axis, and Z-axis directions.

[0002]

2. Description of the Related Art FIG. 4 shows a typical first conventional apparatus for measuring the degree of damage to a ligament of a knee joint (Japanese Patent Laid-Open No. 9-276252).
The displacement of the tibial rough surface Hs is detected by the direct-acting potentiometer P by pressing the back of the calf forward by the calf pressing body F as shown in FIG. The purpose is to determine the degree of damage to the anterior cruciate ligament in the knee joint, and to indirectly measure the degree of damage to the ligament from outside without damaging the patient's body.

As a conventional method for directly measuring the degree of damage to the second ligament, a method is currently practiced in which two incisions are made near the knee as shown in FIG. 5, and an arthroscope is inserted from one of them. This is a method in which a medical probe is inserted from the other side, and palpation is performed on the looseness of the ligament by palpation.

Further, a third conventional apparatus for simultaneously measuring the tension and the looseness of an object to be measured (JP-A-8-145828).
As shown in FIG. 6, a hook H is applied to the object B whose tension is to be measured and the fixed portion K having no displacement, and the tension and the tension of the measurement object B are determined from the load and displacement when the measuring apparatus main body D is pulled up. And measure the looseness.

[0005]

The above-mentioned first conventional apparatus can perform a medical examination without causing any pain to the patient, but is affected by the degree of looseness of the joint and the skin or the subcutaneous tissue, and the strength of the original ligament can be accurately measured. It is difficult to measure well, and as shown in FIG. 4, there is a problem that the measurement requires skill because the apparatus is large, expensive and has a complicated structure.

In the second conventional direct diagnosis method, the degree of damage is determined by visual inspection and palpation, so that the experience of the practitioner is affected, and the treatment information or healing information is not quantitative. There was a problem that it was difficult to share information.

The third conventional apparatus for simultaneously measuring the tension and the looseness is based on the premise that the tension of a measurement target B such as a power transmission belt is large as shown in FIG. It is not suitable for the measurement of a small measurement target, and since no measure has been taken to accurately apply the amount of displacement in a direction orthogonal to the longitudinal direction of the measurement target B, the measurement accuracy of the tension and the looseness dimension has been reduced. A problem occurs in reproducibility. Furthermore, in the measurement of the looseness, there is a problem that a special fixing portion must be prepared when there is no fixing portion F.

Accordingly, the present inventor has proposed a X-axis, Y-axis acting on the load transmitting member in a load transmitting member connected to a probe for applying a displacement to the ligament in a direction perpendicular to the longitudinal direction of the ligament and transmitting a load. The load in the axis and Z-axis directions is detected by a three-axis direction load detector, and a gripper for a measurer is formed in a cylindrical member that movably holds the load transmitting member, and the load transmitting member moves. By regulating the amount, a prescribed displacement amount is given to the ligament via the probe, and the respective loads in the X-axis, Y-axis, and Z-axis directions detected by the three-axis direction load detector as a reaction force generated at that time. Based on the above, the present inventors have focused on the technical idea of the present invention that quantitatively determines the degree of damage to the ligament, and as a result of further research and development, have reached the present invention.

An object of the present invention is to solve the above-mentioned problems of the prior art, and to accurately apply a known displacement in a direction perpendicular to the length direction of the ligament and measure the reaction force generated at that time. Accordingly, it is an object of the present invention to provide a hand-held ligament damage measuring device capable of quantitatively diagnosing the degree of damage and the degree of healing of the ligament.

[0010]

A hand-held ligament damage measuring apparatus according to the present invention (described in claim 1) provides a probe for applying a displacement to the ligament in a direction orthogonal to the longitudinal direction of the ligament, A load transmitting member connected to the probe for transmitting a load, and detecting a load acting on the load transmitting member in the X-, Y-, and Z-axis directions in the load transmitting member.
An axial load detector, a cylindrical member having a gripper gripped by a measurer and movably holding the load transmitting member, and a restricting means for restricting a moving amount of the load transmitting member; A predetermined displacement is given to the ligament through the X-axis, the Y-axis as a reaction force generated at that time,
Each load in the Z-axis direction is detected by the three-axis direction load detection unit.

[0011]

According to the hand-held ligament damage measuring apparatus of the present invention having the above-described structure, the load transmitting member movably held in the cylindrical member having the grip portion gripped by the measurer is provided. By regulating the amount, a prescribed amount of displacement in a direction perpendicular to the longitudinal direction of the ligament is given to the ligament via the probe, and the respective loads in the X-axis, Y-axis, and Z-axis directions are generated as reaction forces at that time. The three-axial load detector detects the load in the X-axis, Y-axis, and Z-axis directions, and enables quantitative determination of the degree of damage to the ligament.

[0012]

According to the hand-held ligament damage measuring apparatus of the present invention having the above-mentioned effect, the ligament is perpendicular to the longitudinal direction of the ligament via the probe by regulating the amount of movement of the load transmitting member. The amount of damage in the ligament is quantitatively determined based on the X-axis, Y-axis, and Z-axis loads detected by the three-axis direction load detector as a reaction force generated at the time when a prescribed displacement amount in the direction is given. Since the determination can be made, an effect is obtained that it is possible to quantitatively diagnose the degree of damage and the degree of healing of the ligament.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described.
This will be described with reference to the drawings.

(Embodiment) As shown in FIGS. 1 to 3, a hand-held ligament damage measuring apparatus according to this embodiment comprises a probe 1 for imparting a displacement in a direction perpendicular to the longitudinal direction of the ligament. A load transmitting shaft 2 as a load transmitting member that is connected to the probe 1 and has a columnar shape, and the direction in which the displacement is given is the longitudinal direction of the columnar shape.
An X-axis and Y-axis direction load detector 3 for detecting a load acting on the load transmission shaft in the X-axis direction and the Y-axis direction orthogonal to the longitudinal direction of the load transmission shaft and orthogonal to each other.
1, 32; a Z-axis direction load detecting unit 33 for detecting a load acting on the load transmitting shaft in a Z-axis direction which is a longitudinal direction of the load transmitting shaft; An inner cylinder 4, an outer cylinder 5 as a cylindrical member having a gripper 51 that can be gripped by a measurer and slidably holding the inner cylinder, and a displacement amount by which the inner cylinder 4 moves within the outer cylinder 5. And a displacement amount restricting means 6 for restricting the ligament, by applying a prescribed displacement amount to the ligament, and detecting the reaction force generated at that time by each of the load detection units 31, 32, 33 in the X-axis, Y-axis, and Z-axis directions. , It is possible to quantitatively determine the degree of ligament damage.

The schematic structure of the hand-held type ligament damage measuring apparatus of the present embodiment is shown in FIG.
1 is attached to the outer cylinder 5, the inner cylinder 4 is a thin-walled cylinder with a trigger 41 slidably held inside the outer cylinder 5, and is integrated with the inner cylinder 4. The load transmitting shaft 2 is connected to the probe 1 and is connected to the probe 1, and the load detecting means 3 is formed on and connected to the load transmitting shaft 2.

By holding the handle 51 in the hand and operating the trigger with a finger, the reaction force when a prescribed displacement is given in a direction perpendicular to the longitudinal direction of the ligament in contact with the tip of the probe 1 is given. X axis, Y constituting the load detecting means 3
By detecting each of the load detectors 31, 32, and 33 in the axial and Z-axis directions, the degree of damage to the ligament can be easily and quantitatively diagnosed.

FIG. 1 is a detailed structural view of the measuring apparatus of the present embodiment shown in FIG. The probe 1 is formed in a key-like shape with its tip bent at a right angle so as to apply a displacement amount in the Z-axis direction orthogonal to the longitudinal direction of the ligament, and is formed of a column-shaped elastic material in which the Z-axis direction is the longitudinal direction. The load transmission shaft 2 is inserted into a cylindrical overload prevention stopper 21,
The probe 1 and the load transmitting shaft 2 are connected by spot welding at two thin portions of the overload prevention stopper 21. The shape of the tip of the probe 1 is
Any shape can be used as long as it can impart a displacement amount in the longitudinal direction of the ligament, and may be a shape other than the key shape.

A part of the load transmitting shaft 2 has a reduced thickness in the X-axis direction for detecting loads in the X-axis direction and the Y-axis direction perpendicular to the longitudinal direction of the load transmitting shaft and perpendicular to each other. A load detector 31 for detecting the load Fx and a load detector 32 for detecting a load Fy in the Y-axis direction are formed. The front and back sides of the Fx and Fy detection units 31 and 32 detect bending strain caused by a load acting on the tip of the probe 1 in the X-axis and Y-axis directions, that is, expansion and contraction strain in the longitudinal direction of the load transmission shaft 2. Is attached with a strain gauge.

In this embodiment, the strain gauge is attached so as to detect the bending strain. However, the present invention is configured to detect the shear strain, that is, the expansion / contraction strain in the direction of 45 ° with respect to the longitudinal direction of the load transmitting shaft 2. Is also good.

A load detector 33 for detecting a load Fz in the Z-axis direction, which is a beam formed of two elastic materials such that the direction perpendicular to the longitudinal direction of the load transmitting shaft 2 is the longitudinal direction, is used. A strain gauge is connected to the end of the transmission shaft 2 by a bolt, and a strain gauge is provided on the Fz detecting section beam so as to detect a bending strain caused by a load in the Z-axis direction applied to the tip of the probe, that is, a stretching strain in the longitudinal direction of the beam. A plurality is attached. In the present embodiment, a strain gauge is attached to each load detecting unit 33, but a strain detecting element may be formed in the load detecting unit 33 by, for example, a method such as vapor deposition.

The load transmitting shaft 2 and the Fz detector 33 are inserted into the thin cylindrical inner cylinder 4, and the Fz detector 33 is joined by spot welding from the outside of the inner cylinder 4. In two places between the Fx and Fy detection units 31 and 32 and the Fz detection unit 33, the rigidity in the direction orthogonal to the longitudinal direction of the load transmitting shaft 2 is high and the rigidity in the longitudinal direction of the load transmitting shaft 2 is high. A thin, thin, disk-shaped leaf spring is joined to the inner cylinder 4 and the load transmitting shaft 2 to support a load and a moment in a direction perpendicular to the longitudinal direction of the load transmitting shaft 2, It is designed so that unnecessary loads other than in the Z-axis direction are not transmitted to the Fz detection unit 33.

The inner cylinder 4 is slidably fitted into the thin cylindrical outer cylinder 5 to which the handle 51 that can be gripped by a measurer is attached, and is welded to the inner cylinder 4. A coil spring 43 is interposed between the flange 42 on which the trigger 41 is mounted and the outer cylinder 5.

A displacement adjusting ring 60 for adjusting the amount of movement of the inner cylinder 4 in the outer cylinder 5 is disposed between the outer cylinder 5 and the inner cylinder 4. The inner cylinder 4
The load transmitting shaft 2 and a part of the probe 1 protruding from the inner tube 4 are covered with a bellows 22 and the inside of the inner cylinder 4 is completely sealed by using a completely sealed output connector 45.

Next, the measuring apparatus of the present embodiment uses the electric circuit as shown in FIG. 3 to output the load detecting sections 31, 32, 3 and 3 through the output connector of the completely sealed type.
In addition to applying a voltage to the strain gauge 3, a voltage signal from the strain gauge is output through a Teflon lead wire, the output is amplified by the amplifier 71, converted into a load, and displayed on the load display device 72. .

The operation of the measuring apparatus having the above-described configuration according to the present embodiment will be described based on an example used in a clinical test of the anterior cruciate ligament.

In the first step, after sterilizing the entire measuring device, an arthroscope is inserted into one of two incisions near the patella, and the other incision contacts the medical probe and the subcutaneous tissue of the living body. Insert a sleeve having an inside diameter enough to allow the probe tip to penetrate so that no resistance is generated.

In the second step, the handle 51 of the measuring device is held in the hand, the tip of the medical probe 1 is passed through a sleeve, and the tip of the probe 1 is hooked on the ligament while being visually observed with an arthroscope. The measuring device is set so that displacement can be applied in a direction perpendicular to the longitudinal direction.
Whether or not the tip of the probe 1 has contacted the ligament may be visually checked, but it is more accurate to confirm that the load display device 72 has slightly output Fz.

In the third step, a finger is put on the trigger 41 attached to the inner cylinder 4 and a wrist is fixed so that the entire measuring device does not move, and the flange 42 joined to the inner cylinder 4 is The trigger 41 is slowly pulled against the urging force of the coil spring 43 until it comes into contact with the outer cylinder 5 to give a known displacement to the ligament, and the Fz output is read by the load display device 72 or recorded on a recorder. .

The displacement of the probe 1 and the load transmitting shaft 2 can be arbitrarily changed by preparing a plurality of displacement adjusting rings 60 having different lengths in advance and replacing them according to circumstances and necessity. In order to accurately apply the displacement in a direction perpendicular to the longitudinal direction of the ligament, the trigger 41 may be pulled while confirming that the Fx and Fy outputs of the load display device 72 are as small as possible. .

In the fourth step, the measurement is completed when the trigger 41 is slowly returned by the reaction force of the coil spring 43 and the probe 1 is pulled out of the living body. When the tip of the probe 1 cannot be hooked on the ligament, the trigger 41 is pulled to the full, and then the tip of the probe 1 is brought into contact with the ligament to release a finger from the trigger 41 and the coil spring 43 The ligament may be pressed using the reaction force of the ligament.

The measuring apparatus according to the present embodiment having the above-described operation can easily set the displacement amount to be applied to the ligament in advance by the displacement adjusting ring 60 as the displacement amount regulating means 6 and operate the trigger 41. Since the displacement can be provided, no special displacement measuring means is required, and the measurer does not need to monitor the displacement amount, so that it is possible to apply the displacement safely and easily. Play.

In addition, the measuring apparatus of the present embodiment can apply a displacement to the ligament while monitoring the load in the Fx and Fy directions, so that a known displacement can be accurately applied in a direction orthogonal to the longitudinal direction of the ligament. Can be granted,
This has the effect that highly accurate load measurement is possible.

Further, in the measuring device of the present embodiment, the load detecting units 3 and 32 detect the load on each of the load detecting units 31 and 32,
Since the structure becomes complicated and large when the 33 is integrated into one place, the separate structure is used to reduce the diameter of the entire structure, and it is small and lightweight, and the operator can easily and easily operate and measure. This has the effect that it can be performed.

The measuring apparatus of the present embodiment has a structure in which a load and a moment in a direction perpendicular to the longitudinal direction of the load transmitting shaft 2 are supported by using a thin disk-shaped leaf spring. Unnecessary loads other than those in the Z-axis direction are not transmitted to the portion 33, and an effect that high-precision load measurement is possible.

The above-described embodiments are exemplifications for explanation, and the present invention is not limited to these embodiments. Those skilled in the art will recognize from the claims, the detailed description of the invention, and the drawings. Modifications and additions are possible without departing from the technical idea of the present invention.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a main part of a ligament damage measuring apparatus according to an embodiment of the present invention.

FIG. 2 is an overall view showing the entire ligament damage degree measuring apparatus of the present embodiment.

FIG. 3 is a circuit diagram showing an electric circuit of the ligament damage measuring device of the present embodiment.

FIG. 4 is a side view showing a main part of a first conventional ligament damage measuring device.

FIG. 5 is an explanatory diagram for explaining a conventional method of directly measuring the degree of damage of a second ligament.

FIG. 6 is a schematic configuration diagram showing a schematic configuration of a conventional apparatus for simultaneously measuring the tension and the looseness of a third measurement object.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Probe 2 Load transmission shaft 31, 32, 33 Load detection part 4 Inner cylinder 5 Outer cylinder 6 Displacement regulating means 7 Judgment means 51 Grasping part

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Atsushi Tsukada 41-cho, Yokomichi, Nagakute-cho, Aichi-gun, Aichi Prefecture Inside Toyota Central Research Institute, Inc. (72) Inventor Akio Osato, Nagakute-machi, Aichi-gun 41, Chuchu-Yokomichi, Toyota Chuo Research Institute, Inc. (72) Inventor Kazio Miki, 41-Cho Chu-Yokomichi, Aichi Prefecture, Aichi-gun Toyota Motor Co., Ltd., Toyota City, Toyota Prefecture, Japan (72) Inventor Mitsunori Makino 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation (72) Hiroaki Kuwahara, 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation F-term (reference) 4C038 VA05 VB11 VB14 VB40 VC20

Claims (1)

[Claims] A probe for applying a displacement in a direction perpendicular to a longitudinal direction of the ligament to the ligament; a load transmitting member connected to the probe for transmitting a load; and a load transmitting member acting on the load transmitting member. X to do
A triaxial load detector that detects a load in the directions of the axes, the Y axis, and the Z axis; a tubular member having a gripper gripped by a measurer and movably holding the load transmitting member; Regulating means for regulating the amount of movement of the ligament, applying a prescribed amount of displacement to the ligament via the probe, and applying the respective loads in the X-axis, Y-axis, and Z-axis directions as reaction forces generated at that time to the three axes. A hand-held ligament damage measuring device characterized by detecting by a directional load detector.