RU2798208C1 - Method for determining the optimal dimensions and configuration of the head of the microscope based on an assessment of individual anthropometric parameters of the operator - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: invention and can be used in procedures involving the use of an operating microscope. The technical result is achieved by using calculations on the bench.

EFFECT: application of the method will allow to maintain the efficiency of the operator for a longer period of time, will avoid irreversible consequences for their health associated with an incorrect posture and non-ergonomic arrangement of parts of the operating microscope used.

1 cl, 11 dwg, 6 tbl

Description

The field of technology to which the invention belongs

The invention relates to medicine and can be used in medical procedures involving the use of an operating microscope.

State of the art

To date, there are various devices and, accordingly, the features of their use, to some extent facilitating the work of the operator of the operating microscope. So, according to the patent of the Russian Federation for invention No. 2331383, a device for controlling the operating microscope "MARIKA" is known, which allows the surgeon to control the microscope without the help of hands, which to a certain extent contributes to a more convenient course of the operation for the operator, since it allows the surgeon not to interrupt in a forced manner operation to place the hand or hands of both hands on the handle or handles of the microscope.

Also known is the device according to the European patent for the invention EP 1738710, which provides for the presence of a switch that allows the surgeon to control the microscope with his mouth, without interrupting the manipulation of his hands in the operating area.

The disadvantages of these devices to facilitate the work of the doctor-operator, and, accordingly, the features of their use, is their narrow focus, which only ensures that when performing certain specific manipulations with the microscope, the doctor-operator will be able to carry them out without interrupting the direct medical action. Such devices and the features of their use as a whole are not intended to contribute to a more ergonomic use of the operating microscope, since they do not provide a system of actions and rules for a functionally and physiologically correct way to use the operating microscope, the use of which could help the operator to work in comfortable conditions for him. well-being and health conditions.

From the prior art at the moment it is not known the existence of effective methods for determining the optimal size and configuration of the head of the microscope in accordance with the parameters of the operator. There is very little literature and scientific research concerning the use of the operating microscope in terms of ergonomics. As a rule, we are talking only about recommendations that are of a general nature.

Disclosure of the essence of the invention

The objective of the present invention is to develop a method for determining the optimal dimensions and configuration of the head of the microscope, based on an assessment of the individual anthropometric parameters of the operator, which will allow the operator to work in comfortable conditions in terms of ergonomic requirements. The application of the method will allow to maintain the efficiency of the operator for a longer period of time, will avoid irreversible consequences for his health associated with an incorrect posture of work and non-ergonomic arrangement of parts of the operating microscope used.

Implementation of the invention

The specified technical result is achieved as follows. As a rule, treatment using an operating microscope is carried out by the doctor in a sitting position, especially if it is carried out using magnification. There are a number of reasons for this state of affairs, but the main one is that the treatment process takes a fairly long time, and the doctor must be relatively immobile. The doctor works many hours a day and, accordingly, it is necessary to work in a position that allows you to make as few unnecessary movements as possible, save energy and, therefore, reduce fatigue and stress levels. Sitting correctly here means sitting in an “ergonomically advantageous, neutral position”, such a correct position is shown in Fig. 1. The doctor in this case takes a position at 12 o'clock relative to the patient, that is, behind his head. This position is the most optimal and versatile when working with a microscope, since it provides a neutral position for the operator and assistant in all types of manipulations and the ability to work both in four and six hands, that is, with one or two assistants.

In FIG. 2 shows the main angles of inclination of the body and bending of the joints, which allow a person to take a neutral position and observe the natural curves of the spine, also marked cervical lordosis 1, thoracic kyphosis 2, lumbar lordosis 3. The body should be in a vertical position along the central axis perpendicular to the floor with support on chair seat. The arms are relaxed, bent at the elbows and lie on the armrests, slightly away from the body, not pressed against the body. The head is not tilted forward or tilted minimally, the gaze is directed forward and into the distance. Also, static tilts of the body and neck to the right or left side of the central axis of the body are not allowed. Head angle (4): 0-15°. Shoulder deflection angle (5): 0-20°. Forearm angle (6): 0-10°. Hip extension angle (7): 90-120°. Knee extension angle (8): 90-120°. Angle of the body axis to the floor plane (9): 90°. Compliance with such angles and body position allows you to reduce the dangerous destructive load on the musculoskeletal system to a minimum. Any deviations from the specified position, associated with restrictions caused by non-optimal technical support of the doctor (inappropriate patient chair, doctor's chair, magnification system) and / or his bad habit, lead to a "forced position", which is dangerous to health and can lead to irreversible disorders of the musculoskeletal system.

Often there is a situation in medical teams when one doctor is higher than another, especially when doctors of different sexes, but they work in the same office and on the same equipment. Therefore, for clarity, let's take two people of different heights, for example, 175 cm and 160 cm, whose schematic figures are shown in Fig. 3. It is obvious that the parameters of the equipment and its settings for a person with a height of 160 cm will differ significantly from those for a person with a height of 175 cm. It can be seen that the position of the doctor in vertical space is mainly influenced by the length of the body and the length of the lower leg. And if the chair is not so difficult to adjust the height and angle of the seat, as well as the position of the armrests, then everything is more complicated with a microscope. Yes, the position of the head of the microscope in space is easily changed due to the pantograph. But it turns out that the dimensions of the head part of the microscope that are comfortable for work and its configuration are directly related to the height of the facial skull, the length of the neck, shoulder, as well as the length of the forearm and palm, since it is these parameters that determine the position of point 0 in space, which will be the starting point in our calculations.

Point 0 is a conditional point in space at which the operator's gaze, directed horizontally forward and into the distance, intersects at right angles with the axis of the microscope objective. Let's take it as the starting point, from which the vertical and horizontal dimensions of the image path from the focus plane to the operator's eyes are calculated. In FIG. 4 there is a diagram with respect to the coordinate axes emanating from the point 0: there are several well-defined segments or distances. The segment 0-Oc, located on the horizontal x-axis, is the distance from the eyes of the operator Os to point 0. This segment depends on the sum of the lengths of the projection of the shoulder Cx, the forearm dx and the area from the wrist to the middle of the palm e on this axis minus the segment G, which is the distance from the axis of the body to the operator's eye. The segment 0-Fph, located on the vertical y-axis, is the distance from point 0 to point Fph (Focus plane hand), which is located in the focus plane Fp (Focus plane) at the intersection of the axis passing through the middle of the operator's palm with the lens axis. The length of this segment is determined by the sum of the lengths of the projections on the y axis of the height of the facial skull a, neck b, shoulder Su, minus the vertical component of the forearm bent at the elbow dy. The segment Fph-Ob is the working distance from the object of observation in the plane of focus to the edge of the lens 14. This segment determines the vertical size of the working area in which all manipulations take place. The 0-Ob segment is the distance from point 0 to the edge of the lens. The segments 0-Ob and 0-Oc determine the region of space in which we must place the head of the microscope, configured in such a way that the edge of the eyepieces is at the point Oc, and the edge of the objective is at the point Ob, then the operator will be in an ergonomically advantageous position. , a neutral position and will be able to observe it in the course of work.

Let us apply the approach described above to the calculation of specific parameters of the ergonomically advantageous, neutral position of the operator and the configuration on their basis of the corresponding head working part of the microscope. As an example, let's take a person of average height, 175 cm high, with a proportional build. We will arrange it sitting according to the scheme discussed above. As can be seen from FIG. 5, the segment O-Fph is calculated as follows:

0-Fph=(a+b+C _y ) - d _y =

\u003d (11 + 8 + 37) - 8 \u003d 48 cm;

and will be equal to 48 cm.

The segment 0-Oc is calculated as follows:

0-OS \u003d (e + d _x + c _x ) - o \u003d (5 + 26 + 11) - 14 \u003d 28 cm;

and will be equal to 28 cm.

All components of the working part of the microscope have their own physical and optical parameters. These parameters may differ depending on the model and manufacturer, but nevertheless, these components themselves are necessarily present, in one form or another. In FIG. 6 shows a schematic diagram of the basic head working part of the Zeiss OPMI pico microscope. Objective 10 is the first microscope lens system. The lens can be fixed focal length, for example, 250 mm, or in the version of the varioscope with variable focal length, for example, 200-300 mm. The housing of the head part of the microscope 11, which contains the second lens system responsible for changing the magnification factor and forming a stereo image. The magnification factor switch can be made in the form of a step switch of the Galileo type or a stepless zoom type. Binocular 12, which transmits the stereo image formed in the microscope body, distributing it to two eyes separately. Eyepieces 13 are the last lens system of the microscope, directly in front of the operator's eyes. Let's evaluate the basic microscope configuration using the same measurement approach that we used to estimate operator parameters. To do this, refer to the diagram in Fig. 7. To achieve the maximum horizontal size, the inclination of the eyepieces must be equal to zero, that is, the eyepieces must be located strictly at 90° to the objective axis. Having located the head part in the coordinate axes, so that the y-axis coincides with the objective axis, and the x-axis with the eyepiece axis, we easily obtain the dimensions of the desired segments. Since at the moment the parameters of the microscope, and not the person, are being evaluated, the points and planes have the corresponding indices. So, we get a segment from point 0 to the edge of the Ost eyepieces (Ocular of microscope, designated as 19), which will be equal to:

0-Ocm=13.5cm

The segment from point 0 to the focal plane of the microscope objective Fp will be equal to:

0-Fp=(0-Ob)+(Ob-Fp)=45 cm,

where Ob-Fp=28 cm

Now you can easily match the parameters of an ergonomically advantageous neutral position of the operator and the basic configuration of the microscope head. Obviously, the 0-Fph of the operator is larger than the corresponding O-Fp of the microscope by 3 cm and the 0-Os of the operator is larger than the 0-Os of the microscope by 14.5 cm. That is, the vertical size and optical parameters of the objective, as well as the horizontal size microscope head are clearly inadequate. Thus, it can be argued that the basic configuration of the microscope cannot be operated by an operator of average height (175 cm), in terms of ergonomics of his work. And even more than that, it can harm his health. The operator will have to constantly tilt the body and head forward to reach the eyepieces and compensate for the lack of horizontal size of the microscope, which will inevitably cause excessive tension in the muscles and ligaments of the back and neck. You will also have to raise your hands above the neutral position to compensate for the lack of vertical dimension.

Therefore, it is necessary to expand the basic configuration of the microscope in such a way as to bring the parameters of the microscope into line with the parameters of the neutral position of the operator. To do this, you need to add components that will help increase the horizontal and vertical dimensions. In our case, these components will be:

1. Varioscope V100 200-300 mm.

2.MORA interface

3. Beam splitter 50/50

4. Binocular f170, 180°

5. Eyepieces 10x

The corresponding diagram of such a microscope configuration is shown in Fig. 8. The diagram shows that the vertical size of 0-Ob has changed slightly, but the varioscope optics increases the Ob-Fp distance to 31 cm, that is, we get the desired 48 cm in terms of the O-Fp parameter. The horizontal dimension of the 0-Ost has been increased by 14cm from the base configuration with the help of the MORA interface, splitter and 10x eyepieces, resulting in a 0-Ost of 27.5cm, which is very close to the optimal parameters. That is, changing and expanding the configuration of the microscope due to the options listed above, not only and not so much increases the functionality of the microscope, as it allows us to achieve the parameters dictated by the ergonomics and anthropometric data of the operator. Moreover, it is not so important, due to which options the desired parameters of the neutral position will be achieved, as important is that they are observed.

Above, we described a conceptual approach to solving the problem of assembling the optimal microscope configuration depending on the physical parameters of the operator. Below we will analyze a practical measurement technique that allows us to obtain the necessary data. For measurements, we used a flat wall with a magnetic board fixed to it, on which you can make marks and place rulers. Sideways to the wall, at an angle of 90 °, a medical chair with armrests is installed. We used an A-dec 521 chair. In order to accurately transfer the operator's parameters to the board, we designed a special measuring stand (Fig. 9). The stand is a rigid metal frame, which is located strictly vertically and parallel to the magnetic board. A laser level is installed on the frame with the help of movable carriages, which allows measuring and determining vertical and horizontal planes with an accuracy of 5 mm per 1 meter of distance. The level on the carriage moves in the plane of the stand frame and, accordingly, parallel to the surface on which measurements are taken. Before starting measurements, it is necessary to correctly find the neutral position. To do this, the operator must sit on the chair and place the forearms with an open palm on the armrests. Find the balance of the body so as not to feel deviations in any direction (right, left, forward, backward). Feel the support on the back of the chair in the lumbar region. Further, in accordance with the scheme shown in Fig. 2, using a measuring stand, the verticality of the body axis and the corresponding deviation angles of the head, shoulder, forearm, and thigh are checked (Fig. 10). If necessary, the height and angle of the seat are adjusted, the armrests and lumbar support are adjusted. After the neutral position is found and the operator has confirmed its comfort, direct measurements are taken. During the measurement process, you must not move or change position in any way. To accurately transfer the projections of the required points onto the board, the laser level is carefully moved in the plane of the stand so that the parallelism of the measurement system is not disturbed. They begin with the installation of the crosshairs of the level in the region of the operator's nose along the axis of the direct gaze of the eyes (Fig. 11). To prevent the laser beam from entering the eyes, it is recommended to close them. A mark is made on the board, this will be the point Os. Then the level moves strictly horizontally until the vertical plane of the laser beam passes through the middle of the palm, a mark is placed at the crosshair point. This will be point 0. After that, the level is lowered strictly vertically until the crosshair is in the middle of the palm, after which it is necessary to remove the palm for the beam to pass unhindered. A mark is placed on the board at the crosshairs. This will be the Fph point. Thus, we got three points - 0, Os and Fph. Now you need to measure the length of the segments 0-Oc and O-Fph. This will be the data we are looking for, which reflects the neutral position of the operator and determines the optimal size and configuration of the head of the microscope.

We evaluated some configurations of the most popular microscopes from various manufacturers on critical parameters such as vertical (O-Fp) and horizontal dimensions (0-Ocm). The measurements were carried out as follows: the head of the microscope was placed over a flat surface, on which the microscope was focused at maximum magnification. After focusing, measurements were taken to the level of the middle of the eyepieces with the inclination of the binoculars equal to 0°. Thus, the O-Fp value was obtained. In the case of a varioscope in the configuration, focusing was carried out in two extreme positions of the focal length regulator and both distances were measured. Then, the length of the segment was measured from the edge of the eyepieces, with the orbital stops fully extended, to the projection of the central axis of the objective. The projection of the axes was refined using a laser level. The measurements were carried out using a standard ruler and square.

The tables show the configurations that are available on the domestic market for purchase. Based on the data presented, it is obvious that the basic configurations of microscopes of all major manufacturers in terms of the 0-Ocm parameter are less than what is necessary for a person of average height and average proportions. Some manufacturers have options that allow you to improve this parameter. These options include extenders (straight and angled), spacer rings, various binoculars, eyepieces, and so on. Zeiss offers the widest range of options. Some of the options, such as the MORA interface or folding binoculars, are exclusive to the microscopes of this manufacturer, but allow you to achieve the highest 0-Ocm values among all the presented manufacturers. These circumstances must be taken into account when choosing a microscope and its configuration. As for the vertical size, here the limitations are primarily associated with the presence of a lens with a fixed focal length in the configuration. As a rule, all modern microscopes are equipped with a varioscope with a variable focal length from 200 mm to 300 mm. The most modern varioscopes have a focal length of more than 400 mm. Thus, microscopes equipped with such a system meet almost any requirements for the O-Fp parameter and are more preferable to purchase.

Brief description of the drawings

Fig. 1 is a general schematic diagram of the work of a dentist with an operating microscope.

Fig. 2 is a diagram of the basic body angles and joint flexion that allow a person to assume a neutral position and maintain the natural curves of the spine.

Fig. 3 is a scheme for comparing the positions of two dental operators with different heights relative to the operating microscope.

Fig. 4 is a diagram of the key axes, points and planes in space that determine the optimal parameters of the microscope.

Fig. 5 is a scheme for calculating the anthropometric parameters of a person with a height of 175 cm.

Fig. 6 is a diagram of the main parts of the head working part of the microscope.

Fig. 7 represents the dimensions and parameters of the basic configuration of the Zeiss OPMI pico microscope head.

Fig. 8 is a diagram of the configuration of the head of the microscope optimal for a doctor with a height of 175 cm.

Fig. 9 is an image of a specially designed measuring stand with a laser level on a movable carriage.

Fig. 10 is a picture of the body vertical axis evaluation.

Fig. 11 is a picture of determining the point Oc.

Industrial Applicability

The method can be widely used in the field of professional medicine in order to maintain the health and performance of medical operators.

Claims (1)

A method for determining the optimal size and configuration of the head of a microscope, based on an assessment of the individual anthropometric parameters of the operator, characterized in that a neutral position is used, in which the operator's body is in a vertical position along the central axis perpendicular to the floor, resting on the chair seat, hands are relaxed, bent at the elbows and lying on the armrests, slightly retracted from the body, not pressed to the body, the head is not tilted forward, the gaze is directed forward and into the distance, as well as the formula for calculating: with point 0 - a conditional point in space, in which the the operator's gaze directed horizontally forward and into the distance, and the axis of the microscope lens with a segment 0-Oc located on the horizontal x-axis and representing the distance from the operator's eyes to point 0 as the sum of the lengths of the projection of the shoulder (cx), forearm (dx) and the area from wrist to the middle of the palm (e) on this axis, minus segment G, which is the distance from the axis of the body to the operator's eye, with segment 0-Fph, located on the vertical y-axis and representing the distance from point 0 to point Fph (Focus plane hand ), which is located in the plane of focus Fp (Focus plane) at the intersection of the axis passing through the middle of the operator’s palm with the axis of the lens, and the length of the segment 0-Fph is determined by the sum of the lengths of the projections on the axis y of the height of the facial skull (a), neck (b) , shoulder (su) minus the vertical component of the forearm, bent at the elbow (dy); the method consists of the following steps: a magnetic board is fixed on a flat wall, on which marks are made and rulers are placed, a medical chair with armrests is installed sideways to the wall at an angle of 90 °, a measuring stand in the form of a rigid metal frame located strictly vertically and parallel to the magnetic board, and a laser level is installed on the indicated frame with the help of movable carriages for taking measurements and determining vertical and horizontal planes, after which the operator sits on the indicated medical chair and places his forearms with an open palm on the armrests, finds the balance of the body so as not to feel any deviations in which of the sides (right, left, forward, back) and feel the support on the back of the chair in the lumbar region in order to take a neutral position, then direct measurements are taken and the points Os, points 0, points Fph are marked on the board, after that measuring the lengths of the 0-Oc and O-Fph segments to determine the optimal dimensions and configuration of the head of the microscope.

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