RU75150U1 - LONG TUBULAR BONDS DIAPHYSIS ENDOPROTHESIS - Google Patents

Abstract

The invention relates to medicine, in particular to devices that are cancer endoprostheses and can be used in traumatology and oncology in the surgical treatment of injuries with an extensive bone defect or tumors of the diaphysis of long tubular bones: shoulder, thigh, lower leg. The technical result of the utility model is to increase the strength of the connection of the protruding parts of the proximal and distal components of the endoprosthesis of the diaphysis of long tubular bones. The technical result is achieved by the fact that in the endoprosthesis of the diaphysis of long tubular bones, consisting of proximal (1) and distal components (2), each of which consists of immersion (3) and protruding (4) parts, the protruding parts are connected using two conical pins (5) with a taper of 1: 20-1: 30, moreover, the conical pins are located at the transition points of the immersion parts in the protruding (6). The claimed design in comparison with the design of the prototype increases the strength of the connection of the protruding parts of the proximal and distal components of the endoprosthesis of the diaphysis of long tubular bones.

Description

The invention relates to medicine, in particular to devices that are cancer endoprostheses and can be used in traumatology and oncology in the surgical treatment of injuries with an extensive bone defect or tumors of the diaphysis of long tubular bones: shoulder, thigh, lower leg.

Damage to the bones of the extremities by malignant, and in some cases benign tumors, until recently led to disability, separation of the patient from his usual work and a decrease in the quality of life. A new direction has been developed in the treatment of these patients. This is endoprosthetics of affected segments of the limbs (replacing bones and joints with artificial materials). The combined treatment of long tubular bone tumors, including the surgical stage, in most cases allowed improving the quality of life of this patient population. The surgical stage of treatment is to remove a large fragment of the bone along with the tumor within the healthy tissue. The resulting defect is replaced by an endoprosthesis.

A known design of a unified endoprosthesis of the diaphysis of long tubular bones, consisting of two components - two rods, which at one end is a cylinder with a rounded base, the opposite end of each of the rods has a landing socket with a mating part in the form of a Morse cone (application for invention No. 2004133602 )

There is also known a method of organ-saving endoprosthesis replacement of the metadiaphyseal part of the humerus and an endoprosthesis for implementing the method (RF patent No. 2155547). The endoprosthesis contains an intramedullary -

made in the form of a truncated ellipsoid having a thread or a geometrical figure close to it for the possibility of penetration from the side of the wound surface into the head of the humerus, while the pin is made conical.

When installing analogue implants, it is necessary to separate both bone fragments to the landing length of the cone, this can cause damage to soft tissues, which is a significant drawback of these designs.

As a prototype for the closest technical essence, we have chosen the design of the oncological diaphyseal endoprosthesis manufactured by the German company Implantcast (catalog of the Implantcast company "Mutars-Münster" (Modular tumor and revision system), C.10 - Diaphyseal implant. The endoprosthesis consists of proximal and distal components , each of which consists of a submersible and protruding part.The protruding parts of the endoprosthesis are interconnected using screw fasteners.

Screw fastening does not provide sufficient joint strength, since such fastening provides for a gap, and with a multi-cycle load of the product, the joint may loose, which will inevitably lead to breakage of the fastener.

The technical result of the utility model is to increase the strength of the connection of the protruding parts of the proximal and distal components of the endoprosthesis of the diaphysis of long tubular bones.

The technical result is achieved by the fact that in the endoprosthesis of the diaphysis of long tubular bones, consisting of proximal and distal components, each of which consists of a submersible and protruding parts, the protruding parts are connected using two conical pins with a taper of 1: 20-1: 30, and conical the pins are located at the junction of the immersion parts in the protruding.

The pins are located at the junction of the immersion parts in the protruding.

Distinctive essential features of the claimed utility model are:

1. the protruding parts of the proximal and distal components of the endoprosthesis are connected using two conical pins;

2. the taper of the conical pins - 1: 20-1: 30;

3. The conical pins are located at the junction of the submersible parts of the proximal and distal components of the endoprosthesis into the protruding.

A causal relationship between the salient features and the result:

1. The presence of the pins provides a gap-free connection, in contrast to the prototype, which, in turn, allows you to create a rigid connection of the protruding parts of the proximal and distal components of the endoprosthesis.

2. The taper of 1: 20-1: 30 conical pins provides the most rigid connection.

3. To ensure maximum rigidity of the connection of the protruding parts of the proximal and distal components of the endoprosthesis, the conical pins should be maximally removed from each other. The maximum removal of the conical pins from each other is ensured by their placement in the places of transition of the submersible parts of the proximal and distal components of the endoprosthesis into the protruding ones.

The set of distinctive essential features is new and allows to increase the strength of the connection of the protruding parts of the proximal and distal components of the endoprosthesis of the diaphysis of long tubular bones.

The essence of the utility model is illustrated by the drawing, where Fig.1 schematically shows the endoprosthesis of the diaphysis of long tubular bones, where:

1. proximal component;

2. distal component;

3. submersible part;

4. protruding part;

5. conical pins;

6. places of transition of submersible parts to protruding.

The device is made of titanium alloy VT-6 (Ti-Al-4V).

The device is sterilized immediately before a surgical operation together with surgical instruments.

The installation of the endoprosthesis is as follows:

They provide access to the pathological focus at the level of the diaphysis of the long tubular bone. Visually determine the size of the tumor. Bone is resected within healthy tissues; if necessary, affected soft tissues are removed. The size of the bone defect is determined. The size of the endoprosthesis is selected in accordance with the size of the bone defect. Using rasps and sweeps, the bone marrow canal of the proximal and distal parts of the bone is treated. Bone cement is injected into the medullary space, after which the immersion parts (3) of the proximal (1) and distal (2) components of the endoprosthesis are introduced. Then, protruding parts (4) of the components of the endoprosthesis are compared with each other and conical pins (5) are introduced into the places of transition of the immersion parts (6). Hemostasis during the operation. Drainage. Layered seam wounds.

The inventive device was tested during operations for 18 patients with tumors of the diaphysis of the humerus (8 patients), femur (6 patients) and tibia (4 patients). Immediate and long-term results were studied in 16 patients ranging from one year to six years. 15 patients achieved good results, and 1 patient (6.7%) developed instability of the femoral diaphysis prosthesis.

Using the endoprosthesis that we selected as a prototype, we operated on four patients. In the long term (two years later), one of the patients (25%) had endoprosthesis instability.

The claimed design in comparison with the design of the prototype increases the strength of the connection of the protruding parts of the proximal and distal components of the endoprosthesis of the diaphysis of long tubular bones.

Claims (1)

The endoprosthesis of the diaphysis of long tubular bones, consisting of proximal and distal components, each of which consists of a submersible and protruding parts, protruding parts are interconnected, characterized in that the protruding parts are connected using two conical pins with a taper of 1: 20-1: 30 moreover, the conical pins are located at the junction of the immersion parts in the protruding.