RU2768603C2 - Method for treatment of infected tumors of distal tibius segment using precision individualized articulated anatomical 3d endoprosthesis spacer - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: invention relates to medicine, namely to oncology and orthopedics, and can be used to treat infected tumors of the distal segment of the tibia using a precision individualized articulatory anatomical 3-D endoprosthesis-spacer. The method includes installing a spacer for temporary filling of the joint cavity in the period between resection of the affected bone segment and installing a permanent endoprosthesis. An individualized articulatory anatomical 3-D endoprosthesis-spacer impregnated with an antibiotic is made in accordance with the individual dimensions of the removed bone area and its anatomical shape. Orienting along the anterior edge of the tibia, the spacer is fixed in the tibial canal with bone cement, according to the principle of coaxiality with the topographic landmarks of the bone, in accordance with the individual anatomy. The surface of the spacer is additionally covered with bio-sponges impregnated with gentamicin. After installing the vacuum drainage system, the wound is sutured tightly.

EFFECT: method ensures the preservation of the functionality of the area of ​​the removed joint and the prevention of the development of periprosthetic infection due to the installation of a spacer covered with bio-gubers impregnated with gentamicin.

1 cl, 6 dwg, 1 ex

Description

FIELD: medicine.

The world standard for the treatment of patients with primary and metastatic bone tumors is a combined approach, one of the stages of which is surgical treatment. Endoprosthetics of bones and joints is the method of choice for the treatment of malignant bone tumors, improves the quality of life of patients and can be performed in 85-90% of patients.

However, despite the improvement of oncological endoprosthesis systems and surgical techniques, the frequency of postoperative complications in oncological endoprosthesis replacement remains high and, according to various sources, ranges from 5 to 50%. In the case of an exophytic component of the tumor with decay or the presence of skin defects in the tumor area, infection of the tumor surface is often noted and increases the risk of developing infectious complications in primary joint replacement in cancer patients.

In order to reduce the risk of infectious complications, a two-stage surgical treatment is carried out. At the first stage, the affected area of the bone is resected with the sanitation of the infectious focus and the installation of a cement spacer impregnated with an antibiotic, which makes it possible to create an antibiotic depot until the next stage of surgical rehabilitation, to preserve the anatomical and functional relationships in the joint and limb. Carry out systemic antibiotic therapy, selected in accordance with the latest positive microbiological study and obtained bacteriogram. At the second stage, after stopping the infectious-inflammatory process, endoprosthesis is performed (Nesichenko D.V. Infectious complications in cancer patients after endoprosthesis replacement of large joints. Clinic, diagnosis, treatment, prevention. // Abstract of the thesis, Moscow, 2010).

The first mention of the use of spacers based on "bone cement" impregnated with antibiotics for the treatment of deep periprosthetic infection dates back to 1988-89 (WildeA.H., RuthJ.T. Two-stagere implantation ininfected total knee arthroplasty // Clin. Orthop. Relat. Res. 1988. Vol. (236) P. 23-35; Booth RE Jr., Lotke PA The results of spacer block technique in revision of infected total knee arthroplasty // Clin. Orthop. Relat. Res. 1989. Vol. 248.Р.57-60), and the first industrial articulatory spacer was introduced in 1992 - the PROSTALAC® - Prosthesis with Antibiotic Loaded Acrylic Cement (De Puy, USA) knee joint system (Duncan CP, Beauchamp CP, Masri B The antibioticl oaded joint replacement system: A novel approach to the management of the infected knee replacement J. Bone Joint Surg. (Br. (supplIII) 1992. Vol. 74.P.296; The PROSTALAC functional spacer in two -stage revision for infected knee replacements / Haddad FS, Masri BA, Campbell D. [et all.] // J. Bone Joint Surg. (Br). 2000. Vol.82. R.807-812).

Domestic developments do not have industrial implementation, most often spacers are made manually and do not have the ability to replace the functionality of a lost joint.

With the development of high-tech 3D technologies, including 3D-printing technology, it became possible to produce individualized articulating 3D cement spacers that repeat the shape of the removed bone segment, which helps to maintain the required volume of the periprosthetic bed for installing a standard endoprosthesis design. Also, the design of the 3D spacer allows the patient to walk with a dosed load on the operated limb while maintaining flexion in the joint, which improves functional results and shortens the rehabilitation period (Sokolovsky A.V., Sokolovsky V.A., Aliev M.D. Long-term results of oncological arthroplasty area of the hip joint with lesions of primary and metastatic tumors // Sarcomas of bones, soft tissues and skin tumors. No. 3-2019, pp. 5-15; Kurilchik A. A., Starodubtsev A. L., Zubarev A. L., Ivanov V.E., Kudryavtsev D.V. Revision arthroplasty in oncological patients, experience of MRRC // Sarcomas of bones, soft tissues and skin tumors. No. 3–2019, pp. 35—42).

Spacer - a device based on biocompatible materials certified for use in medicine (polymethyl methacrylate, metals) with the inclusion of substances with antimicrobial activity, used to temporarily fill the joint cavity, in this case, at the first stage between resection of the affected bone segment and the installation stage permanent endoprosthesis in a patient with an infected tumor of the distal tibia.

The closest (prototype) is a method for manufacturing an individualized articulatory 3-D endoprosthesis-spacer of the knee joint (RU 2736119). In the CT image of the DICOM format, a fragment of the image corresponding to a limb with a previously installed endoprosthesis is isolated, spatial-frequency filtering and image segmentation are performed with the selection of surfaces of bone tissue, internal borders of intramedullary canals, surfaces of metal implants and areas of bone cement, the resulting surfaces are saved as points, which are approximated into many triangles and a three-dimensional STL file is obtained and, by the method of reverse engineering using reference points, full-fledged closed 3-D models of the tibial and talus parts, their assemblies and connection nodes, then a “virtual fitting” of the endoprosthesis-spacer is carried out in three-dimensional graphic editors, the bioadequacy of the design, joint mobility, ease of manufacture and implantation are evaluated, they work on the metal reinforcing part of the endoprosthesis-spacer, simulate the peak load with the construction of stress and strain diagrams using the finite element method using modern CAD systems, after obtaining the final model of the endoprosthesis-spacer on a scale of 1: 1, it is divided into parts and printed on a 3D printer, the resulting master - the model of the future endoprosthesis-spacer is glued, the surface is post-treated and filled with high-temperature bioinert silicone, and the model has technological recesses for centralization of metal frames made of medical stainless steel, which, after the installation of the metal frame, are sealed with bone cement and before the operation, the resulting casting molds and metal bases , are sterilized, the required amount of bone cement is calculated from the volume of the 3-D model, during the revision operation, an arthrotomy of the knee joint is performed, the components of the endoprosthesis are removed, mechanical and drug treatment of the periprosthetic cavities, the required amount of a pre-calculated volume of bone cement impregnated with an antibiotic is kneaded, the spacer metal frame is installed into a silicone mold, silicone molds of the spacer components are filled during polymerization, after the bone cement hardens, the spacer elements are removed from the molds and the spacer surface is finished , the spacer elements are fixed in the canal of the femur and tibia with bone cement according to the principle of coaxiality with the topographic landmarks of the bone, in accordance with the individual anatomy, the spacer elements are interconnected by means of congruent surfaces, the correct axis of the lower limb is restored, the spacer surfaces are additionally covered with bio-sponges impregnated with gentamicin , establish a vacuum, a drainage system, the wound is sutured tightly.

However, in comparison with the method of using one-stage primary arthroplasty after tumor removal, the use of a two-stage technique increases the treatment time to 2-4 months. In all previously described methods, antibiotic-impregnated endoprosthesis-spacers were used to treat periprosthetic infection with permanent metal structures installed. In our proposed method, the use of an endoprosthesis-spacer with an antibiotic prevents the development of periprosthetic infection.

The technical result is the manufacture of an endoprosthesis-spacer in strict accordance with the individual dimensions of the removed bone area, the anatomical shape and quality of the bones at the places of fixation of the spacer elements, maintaining the functionality of the area of the removed joint and preventing the development of periprosthetic infection.

The technical solution is achieved by the fact that, as in the known method, in the period between resection of the affected bone segment and the stage of installing a permanent endoprosthesis, a spacer is installed to temporarily fill the joint cavity.

The peculiarity of the proposed method lies in the fact that an individualized articulatory anatomical 3-D endoprosthesis-spacer impregnated with an antibiotic is made in strict accordance with the individual dimensions of the removed bone area and the anatomical shape, after which the spacer, orienting along the anterior edge of the tibia, is fixed in the tibial canal with using bone cement, according to the principle of coaxiality with topographic landmarks of the bone, in accordance with individual anatomy, and the surface of the spacer is additionally covered with bio-sponges impregnated with gentamicin, after installing a vacuum drainage system, the wound is sutured tightly.

The invention is illustrated by a detailed description, a clinical example and illustrations, which show:

Fig. 1 - photo illustration of the operation: marking the removed segment of the tibia.

Fig. 2 - photo illustration of the operation: a) selection of the affected area of the bone; b) removal of a segment of the affected bone.

Fig. 3 - photo illustration of the operation: installation of the spacer metal frame in a silicone mold.

Fig. 4 - polymerization: filling the silicone mold of the spacer components.

Fig. 5 - spacer: a) extraction from the mold; b) treated surface of the spacer.

Fig. 6 - spacer installation: a) fixation in the tibial canal with bone cement according to the principle of alignment with the topographic landmarks of the bone, in accordance with individual anatomy; b) restoration of tibiofibular syndesmosis with lavsan thread; c) spacer after final installation before wound closure.

The spacer is made as follows.

To develop an articulatory endoprosthesis-spacer, an additive technology is used based on the creation of a three-dimensional model using computed tomographic images of the DICOM format, with an examination accuracy of no more than 2 mm.

An interesting fragment of the image of a healthy tibia is isolated, corresponding to the opposite affected area of the tibia. This image fragment was inverted horizontally so that a "mirror" image of a healthy tibia, without tumor deformity, was obtained, suitable for repairing a defect in the resected segment of the affected bone.

In graphic editors, spatial-frequency filtering and image segmentation are carried out in order to highlight the surfaces of bone tissue, the internal boundaries of the intramedullary canals.

The resulting surfaces are saved in the form of point clouds, which are subsequently approximated by a multitude of micro triangles to obtain STL (stereolithography) format files that are convenient for three-dimensional editing.

Due to the heterogeneous density of bone structures, the resulting surface may have significant defects, such as gaps, duplication, and various noises.

A full-fledged closed 3-D model is built using the method of reverse engineering using reference points, taking into account the requirements developed by the operating surgeon during preoperative planning.

Next, a “virtual fitting” of the endoprosthesis-spacer is carried out in three-dimensional graphic editors, the bioadequacy of the design, joint mobility, ease of manufacture and implantation are evaluated, and the load on the reinforcing part of the endoprosthesis-spacer is calculated.

Using 3-D printing technology, an exact model of the developed endoprosthesis-spacer is created on a 1:1 scale. The resulting 3-D model is post-processed and polished. Next, the master model of the future endoprosthesis-spacer is filled with high-temperature bioinert silicone.

The proposed method is performed as follows.

In the course of surgery, an arthrotomy of the ankle joint is performed with marking of the removed bone segment (Fig. 1). The affected bone is resected following the principles of ablastics (Fig. 2 a, b). Knead the required amount of a pre-calculated volume of bone cement impregnated with an antibiotic (gentamicin, vancomycin, etc.) or add it during the preparation of bone cement, if necessary. Spend the installation of the metal frame of the spacer in a silicone mold (Fig. 3). During polymerization (a "soft dough"-like state), the silicone molds of the spacer components are filled (FIG. 4). After the bone cement hardens, the spacer elements are removed from the moulds, the spacer surface is finally processed - mounting excess bone cement is removed (Fig. 5 a, b).

The spacer is fixed in the tibial canal with bone cement according to the principle of coaxiality, topographical landmarks of the bone and in accordance with individual anatomy (Fig. 6 a, b, c). The articular surface of the spacer, due to individualized design and manufacture, taking into account anatomical features, is congruent to the articular surface of the talus, thereby restoring the correct axis of the lower limb. The surfaces of the spacer are additionally covered with bio-sponges impregnated with gentamicin, a vacuum, a drainage system are installed, the wound is sutured tightly.

Clinical example

Patient Ch., 39 years old with a diagnosis of Adamantinoma of the lower third of the left tibia cT1N0M0G2, stage IIA. Open biopsy of the formation of the left tibia with replacement of the defect with bone cement dated August 28, 2018. Osteomyelitis of the left tibia, a functioning fistula of the anterior surface of the lower third of the left leg. Surgical treatment (stage 1, November 29, 2018, segmental resection of the lower third of the left tibia with the installation of a cement spacer with an antibiotic). 2nd stage on May 15, 2019, endoprosthesis replacement of the left ankle joint with an individual modular endoprosthesis), pT1N0M0G2. Associated diseases: no.

For the first time, the symptoms of the disease appeared in December 2017, when pains in the region of the lower third of the left leg began to bother, aggravated by physical exertion and at night. The diagnosis of adamantinoma was verified.

In May 2018, she turned to a traumatologist at the place of residence, X-ray, MRI, SCT of the left leg were performed - a focus of lytic destruction of the lower third of the tibia was detected.

On June 22, 2018, a trephine biopsy of the formation was performed. With morphological and IHC studies, it is not possible to speak unambiguously about the morphology of the tumor.

08/07/2018 PET-CT was performed: Data were obtained on the presence of active tumor tissue in the lower third of the left tibia.

On August 28, 2018, an open biopsy of the formation of the left tibia was performed with the replacement of the defect with bone cement.

09/17/2018 verified: Adamantinoma of the bone.

In October 2018, the appearance of a fistulous tract with purulent discharge is noted. The patient applied to the MRRC. Discharge from the fistula was sown with the determination of flora and sensitivity to antibiotics, Acinetobacter baumannii, Staphylococcuss ciuri were sown. Conducted 2 courses of antibiotic therapy for the sensitivity of the flora with a positive effect. Given the presence of a chronic focus of infection, the patient is shown a 2-stage surgical intervention.

1st stage of surgical intervention (November 29, 2018): segmental resection of the lower third of the left tibia. In the course of surgery, an arthrotomy of the ankle joint was performed with marking of the bone segment to be removed, observing the principles of ablastics, retreating from the edge of the tumor by 5 cm. The required amount of a pre-calculated volume of bone cement impregnated with an antibiotic (gentamicin) was mixed. The spacer metal frame was installed into a silicone mold. During polymerization (like a "soft dough" state), the silicone mold of the spacer component is filled. After the bone cement hardened, the spacer was removed from the mold, the spacer surface was finished, and the assembly excess bone cement was removed.

The spacer is fixed in the tibial canal with bone cement according to the principle of coaxiality with the topographic landmarks of the bone, being guided by the anterior edge of the tibia. The surface of the spacer was additionally covered with a bio-sponge impregnated with gentamicin, a vacuum drainage system was installed, and the wound was tightly sutured.

Due to the fact that the articular surface of the spacer is congruent to the articular surface of the talus, the correct axis of the lower limb is restored.

Within 1.5 months after the operation, antibacterial therapy was carried out, selected according to the sensitivity of the bacterial flora. Then three times the seeding was made from the bed of the spacer - the growth of microflora was not detected.

2nd stage of surgical intervention (05/15/2019): Revision arthroplasty of the left ankle joint with a modular oncological endoprosthesis.

At the moment, there are no data for a relapse of the underlying disease and an infectious-inflammatory process, the follow-up period is 22 months.

The use of the developed method is of medical, social and economic importance and allows:

- to make an endoprosthesis-spacer in strict accordance with the individual dimensions of the bone section to be removed, the anatomical shape and the quality of the bones in the places of fixation of the spacer elements;

- preserve the functionality of the area of the removed joint;

- to preserve the partial support ability of the limb, due to the use of a high-strength reinforcing frame;

- make a spacer during the operation;

- facilitate the installation of the endoprosthesis at the second stage of treatment, due to the exact preservation of the shape of the bed of the removed bone area;

- maintain the functionality of the joint potential after the 1st stage of treatment (bone resection) and conduct a more intensive program of rehabilitation treatment after the 2nd stage of treatment.

In addition, due to the use of a high-strength reinforcing frame, the structure is reliable, stable and long-term in operation.

Claims (1)

A method for treating infected tumors of the distal segment of the tibia using a precision individualized articulating anatomical 3-D endoprosthesis-spacer, including the stage of installing a spacer for temporarily filling the joint cavity in the period between resection of the affected bone segment and the stage of installing a permanent endoprosthesis, characterized in that an individualized articulating an anatomical 3-D endoprosthesis-spacer impregnated with an antibiotic in accordance with the individual dimensions of the removed area of the bone and its anatomical shape, after which the spacer, guided by the anterior edge of the tibia, is fixed in the tibial canal using bone cement, according to the principle of coaxiality with the topographic landmarks of the bone , in accordance with the individual anatomy, and the surface of the spacer is additionally covered with bio-sponges impregnated with gentamicin, after installing a vacuum drainage system, the wound is sutured tightly.

Images