RU2421823C1 - Method of simulating tubercular osteitis of various severities - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: cortical layer is perforated near an articular capsule of a knee joint; a canal is formed in a spongy substance of a distal epiphysis of a femoral bone. With using a trocar, a fragment of a haemostatic sponge with a fluid culture of tuberculosis mycobacteria 1×10³ to 1×10⁸ cells/mcl is inserted in this canal. Then, an autogenous bone graft is used to fill a bone defect with isolating an infection area with a cement filling.

EFFECT: faster development of a tubercular process due to the most exact intraosseous introduction of the mycobacteria culture with the preset infection dose, also can be used for developing the surgical approaches to tubercular osteitis of various severities.

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Description

The invention relates to medicine, namely to phthisiology, and can be used to develop methods for the surgical treatment of tuberculous osteitis of varying severity.

The advent of new surgical technologies and the need for a differentiated approach to the choice of surgical tactics in the treatment of tuberculosis of bones and joints determines the need to obtain a model of tuberculous osteitis of varying severity to continue the experimental search for new surgical treatment methods.

The currently used method for modeling tuberculous osteitis near the knee joint in experiments on rabbits was developed by E.N. Blendir in the experimental laboratory of the Leningrad Institute of Tuberculosis Surgery in 1967 (Blendir E.N. Experimental model of tuberculous osteitis near the knee joint. // Pathogenesis and sanogenesis of focal and destructive forms of tuberculosis. - M., 1967). Using this method, access to the internal condyle of the femur is provided. The bone area in the hip epimetaphysis is released. A hole is formed with a diameter of 1 mm, a length of 5 mm, through which a dry culture of Mycobacterium tuberculosis (MBT) is introduced at the tip of the needle at a dose of 0.5 mg. The wound is treated with an anti-TB drug in powder form. The hole is filled with dental cement, a layered wound suture is applied.

The disadvantages of the described modeling method - does not allow the use of various infectious doses; there is no way to get a different severity of the course of the tuberculosis process; there is a risk of infection of the surgical wound by the MBT culture at the stage of its introduction into the formed bone defect; there is a risk of migration of the infection agent with blood flow from the bone tissue, which can change the localization of the focus and the course of the tuberculosis process, and also increases the risk of postoperative complications (abscesses, fistulas); long periods of development of the tuberculous focus.

The objective of the proposed method is to create a model of bone tuberculosis lesions of varying severity.

The problem is solved by perforating the cortical layer near the joint capsule of the knee joint, forming a channel in the spongy substance of the distal pineal gland of the femur, where a fragment of a hemostatic sponge with a liquid culture of mycobacterium tuberculosis in a concentration of 1 × 10 ³ to 1 × 10 ⁸ is introduced using a trocar cells / µl, and then the bone defect is filled with an autologous transplant.

The method is illustrated by drawings, where:

Figure 1:

1. Hemostatic sponge soaked in liquid culture of the Office.

2. Autologous graft.

3. Mandren trocar.

4. The trocar.

Figure 2:

5. Distal epimetaphysis of the femur.

1. Hemostatic sponge soaked in liquid culture of the Office.

2. Autologous graft.

6. Cement filling.

Figure 3:

7. Knee joint of a rabbit.

8. Tuberculous lesion in the distal epimetaphysis of the femur.

6. Cement filling.

Figure 4:

7. Knee joint of a rabbit.

8. Tuberculous lesion in the distal epimetaphysis of the femur.

6. Cement filling.

9. Deformation of the contour of the medial condyle.

The inventive method allows you to:

1. Create a model of bone tuberculosis lesions of varying severity.

2. Speed up the development of the tuberculosis process.

3. Obtain tuberculous osteitis by more accurate intraossal administration of a hemostatic sponge soaked in a suspension of MBT culture with a given infectious dose.

4. Avoid migration of the infection by fixing it with an autologous transplant.

The method is as follows.

For the purpose of general anesthesia and sedation, before surgery, the animal is injected intramuscularly with a solution of Rometar 2% (Xylazinum - a drug for use in veterinary medicine) in a volume of 1.0-1.5 ml. The position of the rabbit on the back. The limbs of colic are fixed on the machine in the most extended position.

Stage 1 - preparation and implementation of surgical access. The skin in the area of the knee joint is trimmed and treated with a solution of iodine. An incision of the skin and subcutaneous tissue 5 cm long is made along the front-medial surface of the lower third of the right thigh, anteriorly and parallel to the lateral ligament. Soft tissues are dissected at the anterior edge of the lateral ligament to the bone and are moved away by the raspator along with the periosteum to the bottom and medially.

Stage 2 - channel formation in the femur. A channel with a diameter of 2 mm and a length of 5 mm was drilled in the area of the released bone site. Bleeding from the cancellous bone is stopped by tamponade of the channel with turunda with hydrogen peroxide.

Stage 3 - autograft harvesting. 1.5-2 cm proximal to the area of infection from the femur cortical bone graft 4 × 2 × 2 mm. It is given a cylindrical shape.

Stage 4 - intraossal introduction of infect. A suspension of MBT culture is prepared at a given concentration (1 × 10 ³ or 1 × 10 ⁸ cells / μl). The required dose of culture is introduced into a hemostatic sponge 2 × 2 mm in size. The resulting infectious agent is installed in a trocar charged with an autologous transplant (Fig. 1). The trocar is installed in the formed bone canal. After that, the hemostatic sponge with the graft is pushed out by the mandrin to the bottom of the bone defect.

5th Stage - filling. The outer surface of the installed graft and the adjacent edges of the replenished bone defect are isolated from the paraossal soft tissues with a cement filling (Fig. 2). A layered suture is applied to the wound.

This infection technique allows the formation of a tuberculosis focus in experimental animals after 2-5 weeks. The timing and severity of the tuberculosis process depend on the infectious dose, which allows the development of surgical methods for treating tuberculosis of bones and joints of various forms.

Example No. 1

Rabbit No. 4 of chinchilla breed, gender - male, initial weight - 2950 g, temperature - 39 ° C.

Intramuscularly introduced 1.0 ml of Rometar solution 2%. The rabbit is fixed in position on its back. The limbs of the rabbit are fixed on the machine in the most extended position. An incision was made of the skin and subcutaneous tissue 5 cm long along the front-medial surface of the lower third of the right thigh, anteriorly and parallel to the lateral ligament. The soft tissues are dissected at the anterior edge of the lateral ligament to the bone and are moved away by the raspator along with the periosteum to the bottom and medially. A channel with a diameter of 2 mm and a length of 5 mm was drilled in the area of the freed bone site. Bleeding from the cancellous bone was stopped by tamponade of the channel with turunda with hydrogen peroxide. 1.5-2 cm proximal to the area of infection from the femur cortical bone graft 4 × 2 × 2 mm. It is given a cylindrical shape. Then the culture of the office at a dose of 1 × 10 ³ cells / µl is immersed in the formed bone channel using a trocar. The channel is replenished with a bone autograft. The infection area is isolated from the soft tissues with a cement filling with careful hemostasis. The wound was sutured in layers tightly with catgut.

In the early postoperative period, the animal was observed daily, the animal was examined, weighed, and the range of motion in the joint was determined. Further clinical examination was carried out 1-3 times a week. When examining the animal, its activity, posture and nature of movement were noted. The operated joint was palpated, compared with contralateral. Assessed the condition of the skin, soft tissues surrounding the joint, determined the amount of mobility in the joint.

It was noted that the animal after surgery was inactive. By 9 days, the weight of the rabbit slightly decreased. Soft tissue infiltration was observed in the area of the postoperative wound. Subsequently, a regression of inflammatory changes in the area of intervention was noted, the amplitude of movements in the joint increased. Upon further observation, it was noted that inflammation and healing of the surgical wound were accompanied by an improvement in the general condition of the animal. The rabbit was active, gained initial mass. By the 30th day, the range of motion gradually decreased.

The animal was withdrawn from the experiment for a period of 30 days. Macroscopic evaluation of the bone preparation included:

1) the state of the myeloid bone marrow of the distal pineal gland of the femur - without degenerative-dystrophic changes;

2) the state of the articular surface of the femur - revealed a thinning of the articular cartilage. The surface of the cartilage had a bluish tint.

Visual examination of other organs and systems did not reveal signs of tuberculous lesion. The presence of a destruction site about 1.0 mm in size was observed at the site of culture injection by the 1st month after infection, which was confirmed by x-ray.

Histological examination showed that in the medial condyle of the distal pineal gland of the femur, a tuberculous lesion with a diameter of 2.0 mm was determined, containing caseous-necrotic masses. Degenerative-dystrophic signs in the form of fatty degeneration of the surrounding spongy bone are noted. The articular cartilage is fibrously changed in the medial condyle, collagen fibers and degenerative changes are visible.

Example No. 2

Rabbit No. 5 of chinchilla breed, gender - male, initial weight - 3100 g, temperature - 38.5 ° C.

The animal was infected by the proposed method. The infectious dose was 1 × 10 ⁸ cells / µl.

Similarly to the described example, a daily detailed clinical examination of the animal was carried out. The rabbit was weighed, the range of motion in the joint was estimated. Observations showed a decrease in activity in the early postoperative period, a decrease in appetite. The course of the wound process was similar to the previous example. On the 14th day, a decrease in the range of movements in the operated joint was noted.

After euthanasia of the animal (30 days after surgery), a macroscopic evaluation of the bone preparation revealed: the contour of the distal pineal gland is deformed due to bulging along the medial surface of the internal condyle; pronounced degenerative-dystrophic changes in the myeloid bone marrow in the distal pineal gland of the femur; articular cartilage is thinned everywhere, in the area of the medial condyle, areas of the absence of cartilage cover are determined. The destruction center had dimensions of about 3.5 mm. No tuberculous changes in other organs and systems were detected.

Histologically revealed a bone-destructive lesion 4 mm in size with caseous-necrotic masses, significant degenerative-dystrophic changes in the form of osteoporosis and fatty degeneration of both condyles, most pronounced in the area of infection. The cartilaginous cover is thinned, sometimes replaced by connective tissue. In the medial condyle, areas of exfoliation and lack of articular cartilage.

Thus, the proposed method allows to obtain bone-destructive foci of tuberculous inflammation of varying severity at one time after infection. This makes it possible to develop tactics for the surgical treatment of tuberculosis of bones and joints at different stages of its development.

Claims (1)

A method for modeling tuberculous osteitis of varying severity by local infection of animals with a culture of tuberculosis mycobacteria, characterized in that the cortical layer is perforated near the joint capsule of the knee joint, a channel is formed in the spongy substance of the distal femoral pineal gland, where a fragment of the hemostatic sponge with a liquid culture of mycobacteria is introduced using a trocar tuberculosis in a concentration of 1 × 10 ³ to 1 × 10 ⁸ cells / ml, and then graft autokostnym fill bone defect in the insulation region STI infection cement seal.

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