DD230696A3 - PRESSURE GALER WITH ELECTRONIC CONTROL AND MEASURING SYSTEM - Google Patents

Abstract

In rheumatology, the pressure gauge with electronic control and measuring system serves to quantify the inflammatory and neutral pressure pain sensitivity. The basic principle is based on the determination of the apparatus required for pain relief and to reach the pain tolerance limit as a semi-objective characteristic. The inventive pressure application system is designed in its dimensions and functional parameters for a largely standardized and at the same time universal application in the very different Fingereinzelgelenk-, hand, forefoot, forearm, shin and forehead areas in rheumatoid arthritis patients. The detection of the pressure-gulometric parameters of the relevant for therapeutic defects assessments and representative Greenslean character by lateral compression of the finger joints II-V and Vorfuesse is met by appropriate design of the system. The application of a defined, wegarm and linear in the order of 0-250 Newton increasing pressure is realized by a force balance system with integrated drive unit, wherein an electrically coupled scanning and display system reproduces the pressure force generated simultaneously and stores the characteristics of a series of measurements. A partially programmed control system ensures all preselection functions and an unobtrusive operation of the device for the examiner.

Description

Title of the invention

Pressure gauge with electronic control and measuring system

Field of application of the invention

In rheumatology, the device is used to quantify inflammatory pressure pain across single or multiple adjacent joints in the hand and forefoot, and to determine "neutral" pressure sensitivity (pressure sensitivity) over comparable non-inflammatory areas (forehead, forearm, tibia).

The inflammatory (arthritic) pressure pain is comparable after clinical experience with the local arthritic spontaneous pain. For the occurring in 2% of the population and thus the most common inflammatory rheumatic disease, rheumatoid arthritis, the involvement of the finger and toe joints is particularly characteristic. Therefore, in this disease, the pain provoked by lateral compression pressure on the metacarpophalangeal joints HV (Gänssien's sign) in its algometric parameters correlates significantly with the spontaneous pain detected with the visual analogue scale, with manual functional parameters (gripping force) and systemic process activity and is especially for the therapy efficiency assessment a sensitive, representative and gu ^f . comparable characteristic value.

According to the literature, the "neutral" pressure sensitivity is a partial component of the individual sensitivity to pain and is therefore suitable for the relativization of arthritic pressure pain.

Characteristics of the known technical solutions For the quantification of the arthritic pressure pain of individual joints exist according to the literature a "Dolorimeter" after McCarty, gate and Phelps (Arthrit.Rheumat., 8 (1965) 551-559), a "Palpameter" after Hollander (Arthrit.Rheumat 6 (1963) 277-283) and a pressure gauge according to Rejholec (Schweiz.Rundschau) Med. (Practice) 61 (1972) 1588-1592). The latter was available for own investigations and represents the pneumatic coupling of a pressure application system to a blood pressure gauge with the interposition of a 1-1-glass balloon as pressure equalization vessel. By manual actuation of a Tonometergummiballons a measurable increase in air pressure is generated in the composite system that a sliding piston with printhead on presses the finger joint to be examined. Significant disadvantages are the inconsistency of pressure increase per unit of time, too small a measuring range (up to 300 mahg equivalent to 60 Newton) and above all its sole applicability for fingertip joints. Furthermore, the manual operation of the operator is too much of the actual measurement process and the required observation distracted by the patient. A "device for measuring the (neutral) pressure pain threshold on the tibia front surface of the human" based on the principle of pneumatic pressure transmission and measurement was also found according to patent 52629/1966 (DD). Apart from its limited application, this device does not fulfill the standardization conditions that are indispensable from the methodological and neurophysiological point of view for comparative investigations, superficially in the sense of a constant and linear pressure increase.

Similar disadvantages arise in the pressure gauge according to Keele (Lancet 1 (1954) 636-639) for investigations in the neutral Stirnbareich (Huskisson, Hart: Brit.Med.O. 4 (1972) 193-195) and in which on the same principle based og. Dolorimeter according to McCarty for the quantification of the "articular tenderness", ie the joint sensitivity or arthritic pressure drought. Both algometers consist of a movable pin-shaped pressure applicator of 5 mm diameter and a surrounding metal cylinder. If the metal cylinder with the pressure applicator protruding at the open end is pushed with increasing force towards the

Pressing region pressed so pushes the pin against the resistance of a compression spring into the cylinder. The appended pressure force can be read off on a calibration scale. Even if Huskisson additionally uses a metronome for the approximate time constant of the pressure increase; the measurement is cumbersome, the measurement results are not to save and poorly reproducible. Measuring accuracy and width do not meet the requirements. Differential pressure measurements of the Gänssien's sign, which are relevant for therapy evaluation and closely related to spontaneous pain, are not possible with all reproduced devices, their range of use is thus limited.

Furthermore, a "device for defined position and path-independent force determination and measurement in medical examination devices" developed according to OS 2638169/1978 (DE) was developed for the purpose of eye pressure measurement. The pressure force is generated by a solenoid system, transmitted via a pivotable, two-armed lever and a contact body can be placed on the investigation body and measured and controlled by means of the power supply. Disadvantages exist in the non-given linearity of the force increase, in the limited, not suitable for algometric applications Druckapplikations- and -meßbreite and high production costs.

Object of the invention

The aim of the invention is to quantitatively detect the arthritic pressure pain of individual joints and representative joint groups and to make the local inflammatory with the primarily non-inflammatory pressure sensitivity comparable by additional measurement of the neutral pressure sensitivity. The essential characteristic is the pressure force required to reach the pain threshold and tolerance limit, ie, to be applied and measured simultaneously under standardized, comparable and reproducible conditions.

Presentation of the essence of the invention

The invention has for its object to provide a functioning in all specified areas of the body druckalgometrisches device system, which with exactly comparable technical

see standards and without major loss of path a mechanized, electronically controlled and measurable, time constant increasing pressure application as nociceptive, pain-generating stimulus guaranteed.

The object is achieved in that replaceable, opposite to a bow-shaped tripod mounted, differentiated methodical and anatomical requirements corresponding pressure applicators and abutments are used with largely standardized contact surfaces of the print application. The different dimensions of the hand, forefoot, forearm, shin and forehead areas to be algonomized are taken into account by the dimensioning of the bow-shaped stand and the adjustable and lockable abutments. The shape and size of the respective pressure or contact surface ensure the application of the blunt pressure stimulus required from the clinical and neurophysiological point of view.

In the quantitative recording of the clinically and in particular for therapy efficiency assessments very important Gänssien'-see sign in the form of the required for the pain compression lateral compression of the finger base joints HV and the forefoot is with the help of an additional, laterally adjustable on the bow-shaped tripod abutment a bulging and Dodge the hand and forefoot avoided.

The pressure applicator is firmly connected to the power arm of a force balance system, its contact surface forms a plane with the serving as a support upper housing surface. The center of gravity of the vehicle scale system coincides with its low-friction pivot axis. In the force balance system, the required constantly increasing pressure force is realized without major loss of path through an integrated drive unit, which shifts a weight on the load arm by means of a spindle. A coupled electronic control, measuring and storage system meets the requirements of a mechanized algometric measuring series. In terms of safety, additional impairments of the previously damaged 'joints by' presettable, not to be exceeded maximum load values and a laterally projecting handle

currently possible instantaneous print interruption avoided.

The linearly increasing pressure load can with the help of a. Rotary switch can be varied according to preselectable different speed levels, while the not relevant for the Druckalgometrie pressure relief process using a fast reverse. When the pain tolerance limit is reached, automatic pressure relief is ensured. For the application of a static pressure, a time limit is preselected.

Under the specific medical conditions, only a few alternative solutions are possible for the universal application of the pressure gauge. The disadvantages of an electromagnetic principle of action have already been described; a principle possible hydraulic composite system would be associated with high susceptibility. A vessel attached to the load arm of a lever system in a specific gear ratio with a standardized and calibrated liquid feed does not offer the possibility of precise measured value processing or storage.

The need for a standardized, path-independent simultaneous pressure application and measurement with measured value storage and a universal use in different body regions of the patient is best met with the principle of mechanical force balance.

Exemplary embodiment Static description

The zweitei1 ige device consists of a metered pressure-generating, outwardly disguised force balance with attached pressure application system shown in FIG. I ₁ 2 jnd a located in a second unit electronic measuring and control system with digital data display and storage of FIG.

Pressure application system

The replaceable pressure applicators 1, 2 are attached to the power arm 3 of a force balance system, at its fixedly connected to a base plate 4 bow-shaped stand 5 by means of a clamping screw 6 opposite the likewise replaceable abutment 7, 8 and a lateral abutment 9 adjustable and lockable. Dimensions and shape of the bow-shaped tripod 5 and the pressure applicators 1, 2 and abutment 7, 8, and the applicable pressure correspond to the intended use of the device, the arthritic and "neutral" pressure pain sensation in such different areas as finger joint, metacarpus and head (forehead ) to eat. The contact surfaces of the pressure applicators 1, 2 form at zero position of the power balance system with serving as a support upper housing surface 18 a plane.

Pressure force generation system

The linearly increasing pressure force generation is used in its center of gravity by a rotation axis 16 on the stand 5 with low friction mounted weight system of FIG. 1, in which an integrated drive unit 10 via a spindle 11 a by means of a Roilagers 12 on Lastarm 13 stored weight 14 shifts. By installed Endkontaktschalter 15 while the output and end points of the weight 14 can not be exceeded. The projecting through a slot on the side housing 18, provided with a handle Lastarmende 19 is used in safety technology at any time possible immediate pressure interruption. On the motor-driven spindle 11 17 pulses for the digital pressure force display are generated by a scanning unit.

Pressure force registration and control

Fig. 3 shows the front view of serving as a measuring and control panel of the device. The applied pressure is simultaneously displayed continuously. The storage of each 3 compressive force values of a single reading series (pressure sensation, threshold and pain tolerance) takes place in a three-part and three-digit digital display system 30 / I-III

by pressure on the buttons 23, 24, 25 provided with light signals. The constructive design of the device allows a measuring width of O - 250 Newton. To control the pressure load are the device switch 29, the switch 21 for the pressure increase, switch 22 for the rapid pressure relief and the stop switch 20. The rotary switches 26, 27, 28 allow the preselection of a total of 5 speeds of pressure increase (60, 80, 100, 120 and 140 newtons / min.), The preselection of the maximum compressive force to be used as a safety measure for previously damaged joints and the preselection of a time limit for a static pressure load. The duration of a static load is displayed in the display system 30 / T.

Fig. 6 shows the essential elements of the electronic control and measuring system 35. A logic network 36 is connected at its inputs to the switches 20, 21, 22 and the rotary switches and 28.

At the outputs are the control signals Sl, S2, S3 and S4 ready. The control signal Sl serves to block or enable the clock generator 33, which is connected to the drive unit 10 via a power and direction reversal system 34.

The control signal S2 is directly connected to the system 34 and optionally causes a reversal of direction of the drive unit 10. The scanning unit 17, which is located on the motor-driven spindle 11 and which is electrically coupled via the connecting line 31 and the NAND gate 38 to the counting register 37 , is controlled via the control signal S3 such that only with increasing pressure load from the scanning unit 10 pulses sent to the counting register 37, counted there and can be displayed by the display and storage system 30. The control signal S4 acts directly on the second clock generator 32, which is connected via a further input of the NAND gate 38 to the counting register 37.

function Description

With the algometer according to the invention, a constantly measurable constant increasing pressure is applied to defined areas under standardized conditions. The thus in arthri-

tical and neutral regions induced experimental b ^ zw. Inflammatory pressure pain is detected in its essential characteristics, the pressure applied for pressure sensation, pain threshold (or triggering) and tolerance pressure force by these parameters are entered by appropriate operation of the keys 23, 24, 25 in the storage system with appropriate signaling by the patient. With different, easily replaceable pressure applicators, these measurements are made via inflammatory and noninflammatory finger articulations, lateral compression pressure over the metacarpophalangeal joints HV and toe joints IV, at the junction between the middle and distal thirds of the radius and ulna, and over the tibial anterior surface and forehead. The druckalgometrischen measuring points are shown in Fig. 4 and 5.

For the pressure blunt of the neutral and inflamed finger joints P ₁ , P ", a frusto-conical pressure applicator 1 with uniform abutment -7 _f for forehead P" and tibia anterior surface P _{fi is} also a frusto-conical pressure applicator 1, on the opposite side for fixing the head or lower leg as abutment 8 serving concave jaws and for radius and Ulna P. as pressure applicator and abutment concave jaws 2, 8 used. For druckalgometrischen detection of Gänssien'sehen character is on the finger base joints HV and the forefoot with the help of the two concave jaws 2, 8 a lateral compression pressure P ₀ and ? -, exercised, whereby by conditioning one with the aid of a clamping screw 6 on the tripod 5 and lockable lateral abutment 9 avoiding and bulging the hand or forefoot are avoided.

\ or initiation of the pressure application, preselect pressure rise speed (rotary switch 25) and maximum applied pressure force (rotary switch 27) according to medical instructions. The set maximum pressure is not exceeded during the measuring process, a measure that serves the safety of previously damaged joints. The pressure load operation (from zero) is initiated by operation of the key 21. The weight loss on the load arm 13 which is set in motion leads to the linearly increasing pressure

Application to the examination region. By pulses of the scanning unit 17, the applied pressure force in the digital display and memory system 30 is continuously visualized visually simultaneously and stored by operation of the keys 23, 24, 25, the mechanoalgometric threshold and tolerance values. The pressure sensation is signaled by the verbal qualification "pressure", the pain threshold by the expression "pain" and the pain tolerance by "stop" by the patient. Pressing button 25 will interrupt the increasing print transfer. In the previous setting of the rotary switch 28 to 1 see follows immediately the automatic pressure relief, otherwise must be initiated by operating the key 22, the fast return.

The return automatically leads back to the zero position of the weight system, in which the respective pressure applicator is at the same height as the support surface. In case of danger or inadequate patient reactions, the print application can be interrupted at any time either by pressing the buttons 20, 22 (fast rewind) or better by manually lifting the handle 19 on the right side of the load arm on the right side of the mechanical device part.

The function of the electronic control and measuring system 35 will be explained in more detail below. After switching on the operating voltage and the reset by the signal NRM is the entire control and measuring system '' 35 in Grundstelluna in which the drive unit 10 is at rest, in the counting register 37 from both the photoelectric scanning unit 17 and from Second clock generator 32 no counts are offered and in which the counting register 37 and the digital display and memory system 30 are cleared to zero.

By means of rotary switches 26, 27 and 28, the preset functions described above are set. By operating the key 21, the increasing pressure load operation is initiated. The logic network 36 releases via the control signal Sl the clock generator 33, which sets the drive mechanism 10 in motion via the system of power and direction reversal 34 such that an increasing pressure load operation

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starts. At the same time, the sampling unit 17 is prepared by the control signal 'S3 for the delivery of pulses.

The pulses generated in the phase of movement by the scanning unit 17 and counted in the counting register 37, which represent a certain pressure force increment, are stored and displayed in the digital display and storage system 30, triggered by actuation of the keys 23, 24 and 25.

After reaching the maximum by means of rotary switch 27 Druckkraf t to be applied, the time is determined by comparing the preset, stored with the stored pressure in the display and memory system 30 or by pressing the button 25, the drive unit 10 is stopped.

In the following phase, the second clock generator 32 is activated by the control signal S4 so that the count register 37 can count the timing pulses and store and display the digital display and memory system 30.

After reaching the pre-selected by rotary switch 28 time limit for Druckb ^ elastic or by pressing the switch 22, a rapid pressure relief is initiated by the control signal S2 through the system of power and direction reversal, a fast return of the drive unit 10 and a transport of the movable weight in the starting position is initiated.

Upon reaching the starting position, the drive unit 10 is turned off by means of limit switches.

In the digital display and memory system 30, all measured values significant for the measurement are ready for reading until a new rising pressure load is initiated.

FIG. 7 gives an overview of the temporal action of the control signals S1 to S4.

Mean in it

Tl - time of beginning of the Druckalgometrie (triggered by switch 21)

T 2 - time of reaching the max. permissible load

(triggered by rotary switch 27) or at which the increasing load operation is terminated (triggered by switch 20)

T 3 - time at which the static load is aborted

(triggered by switch 22) or at which the time limit of Dr.uckbelastung is reached (triggered by rotary switch 28)

T 4 - Time at which the pressure gauge is back in its initial position (triggered by limit switch 15).

Claims (7)

invention claim 1. pressure gauge with electronic control and measuring system for defined wegarmen linearly increasing pressure force generation and measurement for the quantification of arthritic and neutral pressure pain threshold and tolerance in their mechanical characteristics over comparable body regions, characterized in that fixed to one with the base plate (4) Connected bow-shaped stand (5) on the one hand a force balance system in its center of gravity with a rotation axis (16) is mounted friction, which on its load arm (13) sliding weight (14), an inte.grierte in the system drive unit (10) and a spindle (11) with a scanning unit (17), wherein on the power arm (3) exchangeable, adapted to be examined body locations, standardized pressure applicators (1; 2) are arranged so that their contact surfaces are at rest with the upper surface serving as a support of the housing (18) are in a plane and on the other hand on bow-shaped stand (5) the pressure applicators opposite and laterally lockable abutment (7; S; 9), and an electronic control and measuring system with digital display and storage (35) for compressive force and time characteristics via a connecting line (31) to the scanning unit · (17) and drive unit (10) is coupled. 2. Druckalgometer according to item 1, characterized in that the electronic control and measuring system (35) has a logic network (36) which eingangssei tig with two rotary switches (27; 28) and three switches (20; 21; 22) and on the output side is connected to an input of the sampling unit (17), with an input of a second clock generator (32) whose outputs via a NAND gate (38) and a count register (37) with an input box (23; 24; 25) and an input of a rotary switch (25) adjustable clock generator (33) whose output via a first input of a system for power amplification and direction reversal (34) with the drive system (35), and whose second input is directly connected to an output of the logical network (36). 3. pressure gauge according to item 1 and 2, characterized in that the scanning unit (17) is arranged directly on the spindle (11). 4. pressure gauge according to item 1 to 3, characterized in that / are arranged in the electronic control and measuring system rotary switch for preselecting a Druckanstiegsgeschvvindigkeit (26), a pressure load limit (27) and a time limit for pressure loads (28). 5. pressure gauge according to item I _1, characterized in that the load arm (13) end is provided with a handle (19) which protrudes from the panel (18). 6. pressure gauge according to item 1 to 4, characterized in that the applied compressive force is 0 - 250 Newton. 7. pressure gauge according to item I _1, characterized in that the load arm (13) end contacts (15) are arranged. / λ ti "i. i -'i / i -λ \