RU144041U1 - MODULAR SPACE BAR TARBOARD BOARD - Google Patents

Abstract

The modular spacer of the tibia plateau, made of bone cement, which contains an antibiotic, is a figured plate that maximally repeats the shape and dimensions of the removed tibial component of the knee endoprosthesis, characterized in that the spacer consists of two detachable elements, the figured plate of which is on the distal side has a landing socket, and the leg is made in the form of a reinforced rod having a flat end part and a working hole in the proximal section.

Description

The utility model relates to medicine, specifically to traumatology and orthopedics. It is used at the stage of treatment of complications of total knee arthroplasty in case of purulent-inflammatory diseases.

In severe forms of knee joint pathology, endoprosthetics can restore movement in the joint, significantly reduce pain, which significantly improves the patient’s quality of life, but complications can occur after this complex surgical operation. One of them - purulent lesions in the joint - requires removal of the components of the endoprosthesis. One of the treatment options for purulent complications of arthroplasty is a two-stage method of revision arthroplasty. At the first stage, the infected endoprosthesis is removed and temporarily replaced with a spacer made of bone cement with the addition of an antibiotic. At the second stage, after stopping the purulent process, a revision prosthesis is installed [1].

The bone cement spacer has a dual function: firstly, it fills the voids between the bone elements of the joint, preserving their anatomical relationship, and secondly, it is an antibiotic depot, which allows for a long time to act on the pathogenic microflora in the joint area.

Known options for using as a temporary knee joint spacer the removed metal femoral component of the endoprosthesis (after sterilization) in combination with the tibial component made of bone cement [2] during surgery.

As a prototype of the proposed utility model, “SPACE BOARD OF THE BIG TIBBONE” was selected (Utility Model Patent No. 134034 of the Russian Federation). The disadvantage of the prototype is the inconvenience of installing in the intramedullary canal spacer legs [3].

The essence of the utility model lies in the combination of essential features sufficient to achieve the desired technical result, which consists in facilitating the installation and extraction of the spacer legs.

The essence of the claimed device lies in the fact that it is made of bone cement, which has an antibiotic in its composition, the spacer consists of two compatible elements, one of them is a figured plate that maximally repeats the shape and dimensions of the removed tibial component of the knee joint implant and has a landing on the distal side a nest, as well as a leg, in the form of a reinforced rod having a flat end part and a working hole in the proximal section.

The spacer plateau of the tibia is made directly during the operation, which allows you to individualize the dimensions of the device elements in each case and use an antibiotic to which there is a sensitivity of microflora contained in the patient's body. However, the surface area of the spacer is limited by the volume of the joint and the size of the tibia plateau. The formation of an elongated spacer leg from bone cement during its solidification period significantly increases the antibiotic recoil area in the surrounding tissues, as they are washed by the fluid contents of the joint and blood. An increase in the volume of the contacting surface of the spacer helps to increase the yield of the antibiotic in the tissue and its greater effectiveness in the fight against infection. The length and thickness of the spacer plate-free, legs are limited only by the internal dimensions of the canal of the tibia. The reinforced hole in the leg allows you to easily remove it, and a flat proximal section - to keep the spacer plate from shifting.

The spacer device is illustrated by illustrations:

in FIG. 1 shows a front view of a spacer mounted in place of a remote endoprosthesis;

The figures denote: 1 - the distal femur, 2 - the metal femoral component of the primary knee joint replacement, 3 - the spacer plate of the tibial plateau of the tibia, 4 - the seat socket on the distal surface of the spacer plate, 5 - the hole on the proximal leg , 6 - proximal tibia, 7 - spacer leg, 8 - reinforcing loop inside the spacer leg.

The proposed utility model can be used as follows.

A midline incision produces a skin incision along the anterior surface of the knee joint. Arthrotomy is performed on the medial side of the patella. The elements of the knee endoprosthesis are removed. Perform mechanical and drug treatment of the joint cavity. The removed femoral component of the endoprosthesis is cleaned of bone cement and sterilized. Using a new portion of bone cement with a pre-added antibiotic, the indicated femoral component 2 of the endoprosthesis is placed on the distal femur 1. From bone cement, which has an antibiotic, the leg of the spacer 7 is made intraoperatively in the form of a rod, reinforcing it along the entire length of the central axis steel wire in the form of a closed loop 8. When the knee joint is maximally bent, the spacer leg 7 is inserted into the intramedullary canal. In the process of final polymerization (solidification) of bone cement (8-10 min.), It is repeatedly removed and immersed from the canal of the tibia 6, to ensure subsequent mobility. In the final position, the spacer leg should protrude slightly above the cut surface of the tibia. The end part of the proximal section of the leg is flattened, and through the loop of the reinforcement 8, a through working hole 5 is formed.

From the next portion of bone cement with an antibiotic, an oval-shaped spacer plate 3 is formed. The diameter of the plate and the thickness should correspond to the size of the removed tibial element of the knee endoprosthesis. Before the cement hardens, it is laid on a slice of the tibia plateau 6, and a landing nest 4 is formed on the surface adjacent to the bone in the shape of the protruding part of the spacer 7. The knee joint is unbent and held in a stretched state until the bone cement is polymerized.

Next, the integrity of the joint capsule is restored, the wound is sutured in layers with the installation of a drainage system. Physiomechanotherapy is subsequently prescribed. Walking is allowed after 2-3 days, with a partial load on the operated limb and the use of crutches.

Clinical example

Patient F., 67 years old, operated on in 2012 for gonarthrosis, developed a para-prosthetic infection. 16 months after the initial operation, a fistula opened. Taking antibiotics and non-steroidal anti-inflammatory drugs stopped the pain only for a while.

In October 2012, the knee joint prosthesis was removed. The femoral component is cleaned of bone cement, sterilized and mounted on bone cement with an antibiotic in its original place. Instead of the tibial component from bone cement with an antibiotic, a spacer plate was made, which in size and shape is as close as possible to the remote tibial component of the endoprosthesis. The plate is mounted on the aminated spacer leg. A drainage system is installed. In the postoperative period, there was no increase in temperature. The patient was discharged for outpatient treatment. For three months, the patient walked with partial support on the operated limb, using crutches. The wound was closed by primary intention.

In March 2013, the spacer was removed and replaced with a revision knee replacement prosthesis. Subsequent observation led to the conclusion about the effectiveness of the intervention using the inventive spacer.

INFORMATION SOURCES

1. Kulyaba T.A., Kornilov N.N., Tikhilov P.M., Novoselov K.A. et al. Revision knee replacement: infectious complications (part 2). // Endoprosthetics in Russia. All-Russian monothematic collection of scientific articles. - Kazan-St. Petersburg. 2007. Issue 3. - P. 165-174.

2. Masri B.A., Ducan C.P. Beauchamp S.R. The modified two-stade exchange arthroplasty in the treatment of the infected total knee replacement: the PROSTALAC system and other articulated spacers // Revision total knee arthroplasty. Baltimore. Williams & Wilkins. - 1997 .-- P. 394-422.

3. Spacer plateau tibia. Patent for utility model of the Russian Federation No. 134034.

Claims (1)

The modular spacer of the tibia plateau, made of bone cement, which contains an antibiotic, is a figured plate that maximally repeats the shape and dimensions of the removed tibial component of the knee endoprosthesis, characterized in that the spacer consists of two detachable elements, the figured plate of which is on the distal side has a landing socket, and the leg is made in the form of a reinforced rod having a flat end part and a working hole in the proximal section.