RU2821658C1 - Method for imitating connection of ulnar and radial bones with polycaprolactone when creating anatomical preparation of forearm bones - Google Patents

Abstract

FIELD: medicine; anatomy.

SUBSTANCE: method for imitation of connection of ulnar and radial bones with polycaprolactone during creation of anatomical preparation of forearm bones consists in the fact that polycaprolactone is used for fixation. Polycaprolactone is placed in a container with water at temperature of 65 °C, waiting for the material to become completely transparent and plastic, anatomically correct positioning of ulnar and radial bones and proximally applying a mass along interosseous edge of two bones, after which a syringe with ice is immediately applied, thereby fixing them, and repeating a similar procedure from the distal side. After that, the main part of the material is applied, attached to the interosseous edge of the radial and ulnar bones, and a syringe cylinder with ice is immediately applied.

EFFECT: invention provides the best visualization of the bone fixation apparatus.

1 cl, 3 dwg, 2 ex

Description

The invention relates to anatomy, forensic medicine, pathological anatomy and can be used to study osteology and arthrosyndesmology.

The classic method for studying arthrosyndesmology is the production of native anatomical preparations preserving all elements of the bone connection. But given the current difficulties in obtaining cadaver material, this becomes difficult to implement. Since cadaver material not fixed in formaldehyde is required, which after initial preparation is placed for maceration in water for 10-15 days, after which the remaining soft tissues of no interest for study are removed and kept for 2-3 days in glycerin, covered with a thin layer of gelatin and exposed [ 1].

In this regard, there are techniques that make it possible to simulate certain types of compounds on already prepared bone preparations of bones, including those that were lost during digestion or maceration. But there is no single method that would allow simulating both ligaments and cartilage joints, while holding bone preparations without the help of fixing elements (wires).

To simulate the joints of the spinal column, the following technique is used: between the vertebral bodies, plates made of leather, cardboard, rubber or felt, the size of intervertebral discs, are inserted and glued. The rod is strengthened in the sacral and cervical sections of the spine, for which a hole is made in the rod through which a wire is inserted, fastening it to the vertebrae of these sections [1]. This technique is quite simple to implement, but has a number of significant disadvantages. With this technique, it is impossible to simulate the anterior and posterior longitudinal ligaments, and it is also necessary to select the thickness of the material to simulate the intervertebral disc, which may affect the information content of the preparation and its visual perception. Moreover, if the vertebrae have signs of osteochondrosis, choosing the thickness of the material becomes even more difficult, which will also lead to a decrease in information content.

To connect long and short bones, as a rule, metal wire is used with preliminary drilling of the bones [1]. This method is effective for mounting the skeleton, but there is no visualization of the fixing apparatus of the bones, which is very important for students to understand arthrosyndesmology. There is also a risk of bone damage during drilling.

In order to imitate the cartilaginous parts of the ribs lost during maceration or digestion of the skeleton, they are replaced with plates wrapped in strips of fabric. The spacers, which are inserted instead of cartilage in the skeleton, are lubricated with a mixture of wood glue and chalk (liquid PVA glue and gypsum), or Mendeleev putty, and varnished [1]. The method has been used for a long time, but it requires certain experience, dexterity, as well as the need to correctly select the components of the mixture, and there is a risk of damage to the preparation when removing the material. This method was taken as a prototype.

The purpose of the invention is to create a method for simulating bone joints with polycaprolactone when creating anatomical preparations for the best visualization of the bone fixation apparatus. This goal is achieved by placing polycaprolactone in granules in a container with water at a temperature of 65°C, waiting for the material to become completely transparent and plastic, after which it is taken out and applied to one of the bones where the connection is simulated, and fixed by applying a pre-prepared a syringe with ice inside to the attachment site; after which they continue to build the fixing apparatus and similarly fix it, first on the other side, and then along the entire surface of the connection; after this, the drug can be used in the educational process.

We have proposed a method for simulating bone joints with polycaprolactone when creating anatomical preparations. This technique allows you to conveniently simulate any connections of bone anatomical preparations. The use of polycaprolactone has a number of advantages: 1) the substance is odorless and safe to use; 2) the melting point is only 59-64°C [2], easily takes any shape and does not stick to your hands, which allows you to work without gloves; 3) when heated, it becomes transparent, which will reduce the likelihood of errors when applying it to anatomical formations; 4) hardens quickly when cold is applied; 5) has the ability to be reused by heating when making a mistake; 6) is perfectly fixed on the bones; 7) if desired, it can be painted with special dyes, which makes it possible to visualize each ligament in its own color; 8) the plasticity of the material allows you to imitate the course of the fibers of the fixing elements of bones; 9) easy mechanical removal of excess material; 10) does not dissolve in formaldehyde. Using a syringe with ice inside allows you to quickly fix polycaprolactone to the bones. Fixation at one of the attachment points simplifies further work with building the connection of the bones.

The method is illustrated with graphic materials. In fig. Figure 1 shows the first and second lumbar vertebrae of a person before applying the technique. In fig. Figure 2 shows transparent polycaprolactone in the process of simulating an intervertebral disc. In fig. Figure 3 shows the vertebrae after implementing the technique of simulating the intervertebral disc, anterior and posterior longitudinal ligaments.

The method is illustrated by examples.

Example 1. Our method simulates the following anatomical structures: intervertebral disc, anterior and posterior longitudinal ligaments between the twelfth thoracic and first lumbar vertebrae, as well as between the first and second lumbar vertebrae. About 50 grams of polycaprolactone granules were placed in 65°C water and waited until it became completely transparent. Then, part of the material was placed on the intervertebral surface of the body of the second lumbar vertebra and the shape of the intervertebral disc was manually molded, after which the first lumbar vertebra was placed on top and fixed by applying a syringe with ice to the material. Then the anterior and posterior longitudinal ligaments were simulated in a similar manner. As a result of the work, the vertebrae were held in place without drilling or installing a metal wire; the course of the fibers of the anterior and posterior longitudinal ligaments, as well as the correct location and thickness of the intervertebral disc, became clear. The transparency of the material made its placement on the bone more convenient and precise.

Example 2. This method was used to simulate the interosseous membrane of the forearm. Polycaprolactone scraps, which had previously been used to simulate joints of foot bones, were placed in water at 65°C and waited until they became completely transparent, after which they were combined into one mass with a spatula. Then the bones were positioned anatomically correctly and a mass was applied proximally along the interosseous edge of the two bones, after which a syringe with ice was immediately applied, thereby fixing them and a similar procedure was repeated on the distal side. After this, the main part of the material was applied, attached to the interosseous edge of the radius and ulna, and the syringe barrel with ice was immediately applied. As a result of the work, the bones were held in place without drilling or installing metal wire. The plasticity of the material made it possible to attach it precisely to the bones, as well as to remove excess polycaprolactone with a spatula and to mark the course of the fibers on the surface of the material.

INFORMATION SOURCES

1. V.S. Pikalyuk, G.A. Moroz, S.A. Kutya. Methodological manual for the production of anatomical preparations. - Simferopol, 2004. - 76 p.

2. Biodegradable polymers: market report - David K. Platt, Rapra Technology Limited - Google Books.

Claims (1)

A method of simulating the connection of the ulna and radius bones with polycaprolactone when creating an anatomical preparation of the bones of the forearm, which consists in using polycaprolactone for fixation, while polycaprolactone is placed in a container with water at a temperature of 65°C, waiting until the material becomes completely transparent and plastic, anatomically correct the ulna and radius are positioned and the mass is applied proximally along the interosseous edge of the two bones, after which a syringe with ice is immediately applied, thereby fixing them, and a similar procedure is repeated on the distal side, after which the main part of the material is applied, attached to the interosseous edge of the radius and ulna bones and immediately apply a syringe barrel with ice.