RU2737653C1 - Method of treating periprosthetic infection of knee joint with presence of metaepidiophyseal defects - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: invention refers to medicine, particularly to traumatology and orthopedics, and can be used in treating patients with peri-prosthetic knee joint infection. Intramedullary rods are selected on the basis of the width and length indices of preserved bone canals of the femoral and tibial bones. Bent ends of rods are removed, leaving length L of straight part of each rod. L=l1+l2+l3, where l1 is not less than 40% and not more than 60% of the preserved length of the bone canal, l2 is the length of the defect, l3 is the length for attachment of the rods to each other. One-step implantation in femoral and shin-like channels is performed on bone cement with prepared rod antibiotic. Splicing of rods is carried out with overlapping overlapping. Free space of the joint is replaced by bone cement impregnated with an antibiotic. Distal ends of the rods with the formal openings are fixed with static screws.

EFFECT: method enables reducing a probability of recurrent peri-implant infection, arrest the infectious process and prevent the resorption of bone tissues due to the fixative stability and high mechanical strength used in the replacement of metaepidiaphysis defects of the knee joint structure.

1 cl, 2 ex, 10 dwg

Description

The invention relates to medicine, in particular to traumatology and orthopedics, and can be used in the treatment of patients with periprosthetic knee infection.

Total knee arthroplasty is associated with certain risks of complications. The most serious and difficult to treat is periprosthetic infection, which occupies one of the leading positions. Currently, the two-stage re-endoprosthetics procedure using an antibacterial cement spacer remains the “gold standard” in the treatment of infectious complications. Examination of patients with periprosthetic knee joint infection often reveals cases of significant defects in the bone tissue of the articular ends, extensive wound defects in the soft tissues of the surgical site, as well as failure of the ligamentous-capsular apparatus. Bone and soft tissue defects are caused by various factors: previous instability of the components of the endoprosthesis, multiple surgical interventions on the joint area, oncological and purulent-necrotic lesions. In such cases, a static spacer is the option of choice for use in the surgical treatment of deep infection.

There is scientific evidence that shows satisfactory functional results after using static spacers in a timely manner for the final stage of revision arthroplasty (Treatment of Periprosthetic Knee Infection With a Two-stage Protocol Using Static Spacers / Paul Lichstein MD, MS, Sharlene Su BS, Hakan Hedlund MD et al. // SYMPOSIUM: 2015 KNEE SOCIETY PROCEEDINGS).

During revision knee arthroplasty, various bone defects are detected in 93.9% - 100% of cases, with significant defects (IIB - III degrees according to the AORI classification) up to 42%. In addition, each subsequent surgical intervention increases the volume of existing bone defects and the risk of complications. This leads to an increase in the number of patients with PPI and defects in the bone tissue of the knee joint that occur after the removal of the infected components of the endoprostheses. (Methods of compensating for bone defects in revision knee arthroplasty, T.A. Kulyaba, N.N.Kornilov, A.V. Selin et al., 2011; Evaluation of the effectiveness of two-stage surgical treatment of patients with periprosthetic infection of the knee and hip joints, A. M. Ermakov, N.M. Klyushin, Yu.V. Ababkov, A.S. Tryapichnikov, A.N. Koyushkov, 2018).

A known method for the treatment of patients with periprosthetic knee infection in which a block spacer is used. After performing a sanitizing operation with the removal of endoprosthesis components, radical debridement of soft tissues and bone structures, a block spacer is implanted, the basis of which is an intramedullary nail fixed in the bone marrow canals of the femur and tibia in combination with bone cement impregnated with an antibiotic. (Results of staged treatment of patients with periprosthetic infection after knee arthroplasty / P.M. Preobrazhensky, S.A. Bozhkova, A.V. Kazemirsky, M.Yu. Goncharov // Traumatology and Orthopedics of Russia, Volume 23, No. 1, 2017 , pp. 98-107).

However, the possible instability of the device in the postoperative period leads to the formation of new, more extensive defects in bone tissue, which, in turn, increases the likelihood of recurrence of peri-implant infection, requiring additional surgical intervention. Long-term limitation of the function of the lower limb, associated with an increase in the duration of treatment, ultimately leads to unsatisfactory functional results in the patient due to a decrease in the range of motion in the joint.

The objective of the present invention is to develop a method for performing the first stage of revision arthroplasty, which makes it possible to arrest the infectious process of the knee joint in the presence of metaepidiaphyseal defects.

EFFECT: provision of fixation stability and high mechanical strength when replacing metaepidiaphyseal defects of the knee joint, prevention of bone tissue resorption, relief of the infectious process.

The stated technical result is achieved by the fact that at the preoperative stage, intramedullary rods are prepared for implantation into the femur and tibia by removing the curved end from each rod and making two through holes on the side of the remote proximal end for fastening the rods to each other so that the length of the straight part of each rod L = l1 + l2 + l3, where l1 is not less than 40% and not more than 60% of the preserved length of the bone canal, l2 is the length of the defect, l3 is the length of the overlap, intraoperatively after removal of the components of the endoprosthesis, radical debridement of soft tissues and bone structures, perform a one-stage implantation into the femoral and tibial canals on bone cement with an antibiotic of prepared rods, after polymerisation of the cement, the proximal ends of the rods are connected to each other with bolts and nuts, the free space of the joint is replaced with bone cement impregnated with an antibiotic, the distal ends of the rods are fixed her with official holes with static screws.

Preferably, at the preoperative stage, intramedullary rods with diameters of at least 12 mm are selected, the overlap is performed for 50 mm, the holes in the proximal part are made at a distance of 30 mm between their centers.

The method of treating periprosthetic infection of the knee joint in the presence of metaepidiaphyseal defects is illustrated by graphic material, where figure 1 shows an intramedullary rod in two projections with an orientation line for removal (sawing off) of the bent part, in Fig. 2 - prepared intramedullary rods, overlapped.

The method is carried out as follows. In the course of preoperative planning, an X-ray examination is performed in order to determine the size of the defects of the articular ends of the knee joint. Based on the study, the parameters of the width and length of the preserved bone canals of the femur and tibia are determined. Select intramedullary rods based on the parameters obtained as follows. The diameter of the rods, since they are planned to be fixed on bone cement with an antibiotic, should be 1-2 mm less than the true width of the canals. Preferably, intramedullary rods are selected with diameters of at least 12 mm. If the inner diameter of the bone canal is less than 12 mm, then during surgery, the canal is processed using special instruments (orthopedic reamers) to the desired diameter. The length of the intramedullary rod is chosen so that the length of the straight part of the rod L, after removing (sawing off) the curved end of the rod to give a one-plane orientation, satisfies the condition L = l1 + l2 + l3, where l1 is not less than 40% and not more than 60% of the preserved length of the bone canal , l2 is the defect length, l3 is the overlap length (Fig. 1). Then, two holes with a diameter of 6.5 mm are drilled in the proximal sections of the rods (from the distal end) in the overlap zone to create an overlap fastening by means of two bolts and their corresponding nuts, the dimensions of which are selected depending on the diameters of the rods (Fig. 2). Preferably, the overlap is made for 50 mm, the holes in the proximal part are made at a distance of 30 mm between their centers.

Intraoperatively, after removal of the components of the endoprosthesis, radical debridement of soft tissues and bone structures, the rods are immersed in the bone canals so that the holes for attachment with full extension of the limb are centered in the articular cavity and coincide with each other. To check the correctness of the installation, a test bolting of the rods is performed. Then, marks are applied to each rod to determine the immersion level of each of the rods. Further, one-stage implantation of both rods is performed on the bone cement impregnated with antibiotics in the bent knee position, taking into account the previously determined risks. After polymerization of the cement, the limb is extended and fixed with 2 bolts and nuts. The tightening force is carried out until there is no mobility between the rods. Next, the free space of the joint is replaced with bone cement, also impregnated with an antibiotic, the amount of which is selected individually depending on the size of the defect.

Under the control of an electron-optical converter, at the level of the static hole on the distal side of the tibial shaft, access to the cortical layer of bone tissue is provided, then the passage is drilled for the screw to be inserted using a medical drill and an installed X-ray transparent nozzle. The screw size is determined with a special tool (screw channel length gauge). Then the procedure is repeated for the rod installed in the canal of the femur. Static screws allow to evenly distribute the load on the bone tissue, thereby preventing its resorption, as well as providing fixation stability of the spacer with additional rotational stability.

Clinical example 1

Patient K., 69 years old, was admitted to the department of purulent surgery (osteology) with a diagnosis of deep suppuration after revision arthroplasty of the left knee joint. From the anamnesis: about severe pain syndrome and gonarthrosis 3 tbsp. left knee joint in 2011, total arthroplasty was performed. In 2012, 2013, 2016, 2017, 2018 revision arthroplasty of the left knee joint due to a diagnosed periprosthetic infection. Local status upon admission to the department of purulent surgery (osteology): severe pain syndrome when walking, the patient moves with the help of crutches, without loading the left lower limb. Relative shortening of 1 cm. Active movements in the left knee joint are limited, passive, sharply painful, lateral instability. There is a postoperative scar on the outer surface of the left knee joint. In the course of preoperative planning, an X-ray examination was performed in 2 projections (Fig. 3, 4). Computed tomography shows a significant defect in the proximal tibia.

A specialized program was used to measure the internal dimensions and lengths of the preserved bone canals. Considering the presence of a metaepidiaphyseal defect of the proximal tibia (T3 according to the AORI classification).

The length of the canal of the intact femur was 366 mm, the diameter of the canal was 14 mm. The length of the femoral defect was 28 mm. To calculate the final bar length 366 × 40% = 146 mm. Added 50mm for overlapping. Thus, the length of the straight part of the rod is L = 146 + 28 + = 224 mm. An intramedullary nail with dimensions d = 13 mm, l = 290 mm was selected.

The length of the canal of the intact tibia was 228 mm, the diameter of the canal was 12 mm. The length of the femoral defect was 72 mm. To calculate the final length of the bar 228 × 60% = 137 mm. Added 50mm for overlapping. Thus, the length of the straight part of the rod is L = 137 + 72 + 50 = 259 mm. An intramedullary nail with dimensions d = 12 mm, l = 320 mm was selected.

The proximal sections of the rods were sawed off at a level below the bend so that the straight portions of the rods were 224 and 259 mm, respectively. In the area of the future fastening of the rods, two holes with a diameter of 6.5 mm were drilled in the overlap zone 50 mm long at a distance between the centers of the holes 30 mm. To create the fastening between the rods, two bolts with a length of 32 mm with an M6 thread and corresponding nuts are prepared.

Intraoperatively, after removal of the components of the endoprosthesis and the remnants of bone cement, an extensive defect in the proximal tibia was visualized, and the failure of the lateral lateral ligament of the left knee joint was determined. Following the surgical treatment of the purulent focus, the rods were tried on and the marks were applied. The tibial canal was processed using an orthopedic reamer to create the required diameter of the bone canal for installing a 12 mm rod on bone cement with an antibiotic. In the flexion position, the rods are installed in the canals of the femur and tibia on bone cement with the addition of a thermostable antibiotic. After polymerization of the cement, the limb was extended and fixed by 2 bolts with nuts. After polymerization of the cement, the rods are fastened together with two bolts and nuts. Through additional incisions along the anterior surface of the thigh and lower leg, under the control of the image intensifier, two static screws were installed in the official holes of the rods. The residual joint cavity, around the junction of the rods, is filled with bone cement with an antibiotic. The wound was sutured in layers. Performed X-ray control after surgery (Fig. 5, 6).

Surgery was delayed for the patient due to decompensated concomitant disease (contraindication for surgical treatment). After 11 months from the moment of surgery, there were no signs of recurrence of the infectious process, pain did not bother. After correction of the condition, the patient will undergo revision arthroplasty of the left knee joint. Long-term operation of the structure, taking into account the existing loads, allows us to conclude about its high mechanical strength.

Clinical example 2.

Patient A., 68 years old, was admitted to the department of purulent surgery (osteology) with a diagnosis of deep suppuration after total arthroplasty of the right knee joint. From the anamnesis: about severe pain syndrome and gonarthrosis 3 tbsp. of the right knee joint, total arthroplasty was performed in May 2018. The early postoperative period was complicated by suppuration. The course of conservative treatment (antibiotic therapy, local use of drugs) has no effect. Local status upon admission to the department of purulent surgery (osteology): there is no support ability of the right lower limb, the patient moves on a sitting gurney. Relative shortening of 3.5 cm. Active movements in the right knee joint are absent, passive movements are sharply painful. Clinical examination revealed a posterior-external dislocation of the right lower leg. On the outer surface of the right knee joint in the area of the old postoperative scar there is a fistulous wound with purulent discharge. During preoperative planning, an X-ray examination was performed in 2 projections (Figs. 7, 8), which confirmed the presence of a dislocation of the right leg. On computed tomography, a significant defect is determined (absence of the outer condyle of the femur).

A specialized program was used to measure the internal dimensions and lengths of preserved bone canals (d - 14 mm, l - 310 mm for the femoral and d - 13 mm, l - 252 mm for the tibial). Given the presence of a significant defect in the distal femur (F3 according to the AORI classification), the patient's overweight, and also taking into account the length of the preserved bone canals, the following calculations were made:

310 × 60% = 186 mm. The defect length is 41 mm. Added 50mm for overlapping. Thus, the length of the straight part of the rod is L = 186 + 41 + 50 = 277 mm. An intramedullary nail with dimensions d = 13 mm, l = 340 mm was selected.

The length of the canal of the intact tibia was 252 mm. The length of the femoral defect was 12 mm. To calculate the total length of the bar 252 × 60% = 151 mm. Added 50mm for overlapping. Thus, the length of the straight part of the rod is L = 151 + 12 + 50 = 213 mm. An intramedullary nail with dimensions d = 12 mm, l = 280 mm was selected.

The proximal sections of the rods were sawed off at a level below the bend so that the straight portions of the rods were 277 and 213 mm, respectively. In the area of the future overlap of the rods, two holes with a diameter of 6.5 mm were drilled at a distance of 30 mm between the centers of the holes for 50 mm. To create the fastening between the rods, two bolts with a length of 32 mm with an M6 thread and corresponding nuts are prepared.

Intraoperatively, after removal of unstable components of the endoprosthesis, an extensive defect in the distal femur and damage to the ligamentous apparatus of the right knee joint were visualized. Following the surgical treatment of the purulent focus, the rods prepared at the preoperative stage were tried on and the marks were applied. In the flexion position, the rods are installed in the canals of the femur and tibia on bone cement with the addition of a thermostable antibiotic. After polymerization of the cement, the rods are fastened together with two bolts and nuts. Through additional incisions along the anterior surface of the thigh and lower leg, under the control of the image intensifier, two static screws were installed in the official holes of the rods. The residual cavity of the joint, around the junction of the rods, is filled with bone cement with an antibiotic. The wound was sutured in layers. Performed X-ray control after surgery (Fig. 9, 10).

A control examination was performed 4 months after the surgery. No signs of recurrence of the infectious process were found. In conclusion, CT examination: the state after the installation of the spacer. The position of the spacer is satisfactory and stable. Signs of minimal pronounced bone resorption around the tibial section of the spacer structure, mainly in the posterior sections.

6 months after the surgery, the second stage of revision arthroplasty of the right knee joint was performed.

Thus, the method allows to arrest the infectious process of the knee joint in the presence of metaepidiaphyseal defects, to ensure fixation stability and high mechanical strength, to prevent bone tissue resorption, to ensure the successful completion of the final stage of revision arthroplasty.

Claims (2)

1. A method of treating periprosthetic infection of the knee joint in the presence of metaepidiaphyseal defects, characterized by the fact that at the preoperative stage, intramedullary rods are prepared for implantation into the femur and tibia by removing the curved end from each rod and making two through holes from the side of the remote proximal end to fasten the rods overlap each other so that the length of the straight part of each rod is L = l1 + l2 + l3, where l1 is not less than 40% and not more than 60% of the preserved length of the bone canal, l2 is the length of the defect, l3 is the length of the overlap, intraoperatively after removal components of the endoprosthesis, radical debridement of soft tissues and bone structures, one-stage implantation into the femoral and tibial canals is performed on bone cement with an antibiotic of the prepared rods, after polymerization of the cement, the proximal ends of the rods are connected to each other with bolts and nuts, the free space of the joint is replaced Antibiotic-impregnated bone cement is used to fix the distal ends of the rods with official holes with static screws. 2. The method according to claim 1, characterized in that at the preoperative stage, intramedullary rods with diameters of at least 12 mm are selected, the overlap is performed for 50 mm, the holes in the proximal part are made at a distance of 30 mm between their centers.

Images