RU2845525C1 - Method for hindfoot deformation correction - Google Patents

Abstract

FIELD: medical science.

SUBSTANCE: invention refers to medicine, namely to traumatology and orthopaedics, and can be used for hindfoot deformity correction. Method involves performing a preoperative functional multispiral computed tomography and 3D reconstruction of an integral deformed foot model with a distal one-third of shin and separate models of talus and heel bones. Mutual arrangement of separate models of talus and heel bones is changed to achieve reference norm values of investigated talo-first metatarsal and tibiocalcaneal angles, after that, in the cavity between the talus and heel bones, namely in the region of the posterior facet of the talocalcaneal joint, a geometric figure with six rectangular sides is drawn, which height is equal to the cavity height, wherein said outer side height is increased by 6 mm. New contours of the figure are marked, according to which the MSCT model of the graft is created. Surgical intervention is preceded by making an allograft matching its MSCT model in shape and size. On the tomogram of the integral foot in the frontal plane, a first line of the ankle joint is drawn, indenting from it down 1.5 cm and in parallel to it a second line is drawn, on which the first point is marked in the middle of the width of the talus bone, which is a guide for the optimal holding of the fixing screws, and the second point is on the outer border of the tendon of the anterior tibial muscle and the distance between them is measured. For surgical removal of hindfoot deformation using Hintermann distractor, talus and heel bones are separated, and in the region of the posterior facet of the talocalcaneal joint, the articular surfaces of the talus and heel bones are excised at a depth of not more than 2 mm, distractor reaches a distance between the talus and heel bone along the outer edge of the foot, equal to the height of the outer side of graft plus 2 mm, then allograft is impacted into cavity of talocalcaneal joint. Stage of its fixation begins with marking on the skin along the front surface of the extremity of two parallel lines: the first – in the projection of the ankle joint, the second – in the distal direction by 1.5 cm, further, on the second line to the outside from the outer border of the tendon of the anterior tibial muscle, the pre-measured by tomogram distance between the first and second points is measured and the point located in the projection of the middle of the width of the talus bone is marked, and in the direction of this point, two cannulated screws fixing the allograft are inserted.

EFFECT: method provides the complete elimination of the hindfoot deformation, achieving a reliable fixation of the graft between the heel and talus bones, reducing pain syndrome, preventing the loss of correction and the development of recurrent deformation, reduced traumatism, duration of operation and risk of infectious complications, as well as restoration of foot function due to the fact that the resection of the articular surfaces of the talus and heel bones in the region of the posterior facet of the talocalcaneal joint at a depth of not more than 2 mm is sufficient to remove the articular cartilages and achieve osteointegration of the graft, and also contributes to the maximum preservation of the volume and height of the heel and talus bones, which plays an important role in the recovery of the foot function.

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Description

The proposed invention relates to the field of medicine, namely to traumatology and orthopedics, and can be used for surgical treatment of hallux valgus.

There is a known method of arthrodesis of the subtalar joint, which is performed after fractures of the calcaneus in two stages.

The first stage includes modeling resection of the deformed lateral surfaces of the calcaneus, excision of the subtalar joint cartilage, and application of the Ilizarov apparatus to the foot, in which two pins are inserted in the frontal plane through the talus and calcaneus bones and three pins are inserted through the distal part of the tibia to create a gap between the talus and calcaneus bones using microdistraction. Three weeks later, without removing the Ilizarov apparatus, the second stage of the operation is performed, which includes access to the subtalar joint along the old scar on the outer lateral surface of the foot, the surfaces of the talus and calcaneus bones are "refreshed", and bone auto- or alloplasty of the subtalar joint cavity is performed ([1]) Method of arthrodesis of the subtalar joint: Patent 2164389, Russian Federation; IPC A61B 17/56 / V.V. Dolgopolov, A.S. Sati; Applicant and patent holder Russian Research Institute of Traumatology and Orthopedics named after R.P. Vreden - No. 99110124/14; declared 12.05.1999; published 27.03.2001. - Bulletin No. 9).

However, the known method has significant disadvantages, namely:

1. This method does not preliminarily determine the shape and size of the transplant required to eliminate the deformation in each individual patient, which, when using bone auto- or alloplasty of the subtalar joint cavity, due to insufficient or hypercorrection, can lead to an unfavorable outcome in the form of relapse of the deformation and deforming arthrosis, pain syndrome, and impaired foot function.

2. Passing the needles through the spongy talus and calcaneus bones and performing distraction forces on them does not exclude the cutting of bone tissue and the subsequent development of its inflammation up to the osteomyelitic process, especially against the background of a post-traumatic decrease in bone mineral density.

3. The use of the Ilizarov apparatus for performing arthrodesis of the subtalar joint and the performance of two surgical interventions, extended in time, as well as two anesthetic interventions, contribute to the trauma of the operation and increase the risk of infection in the area of the surgical wound of the foot. In addition, the presence of the spokes of the Ilizarov apparatus outside the skin is also associated with a high risk of developing an infectious inflammation of the soft tissues around them.

Also known is a method of minimally invasive arthrodesis of the subtalar joint, which includes access to the subtalar joint by puncturing the skin along the back of the leg proximal to the calcaneal tubercle by 1-1.5 cm along the outer edge of the Achilles tendon, introducing a cylindrical bur into its cavity, which is used to treat the articular surfaces of the posterior part of the talocalcaneal joint. Then, additional access is performed to the anterior part of the talocalcaneal joint by incision of the skin, not exceeding 0.5-0.8 cm, along the dorsal-outer edge of the foot in the projection of the tarsal sinus, carefully treating the surfaces of the calcaneal and talus bones and forming a cavity between them. From a small access (1-1.5 cm) in the projection of the lateral condyle of the femur of the operated limb, a cylindrical burr (1 cm in diameter) is used to take a spongy-cortical autograft no more than 0.5-1.0 cm long and introduce it into the formed cavity. Fixation of the talus and calcaneus is performed with two cannulated compression screws ([2]) Minimally invasive arthrodesis of the subtalar joint: Patent. 2549297, Russian Federation; IPC A61B 17/56 / N.A. Koryshkov, A.S. Khodzhiev, V.T. Zeynalov, A.M. Dzyuba, A.P. Khapilin, K.A. Sobolev; Applicants and patent holders: Koryshkov Nikolay Aleksandrovich, Khodzhiev Artur Safarovich, Zeynalov Vadim Tofikovich, Dzyuba Aleksey Mikhailovich, Khapilin Anton Pavlovich, Sobolev Kirill Aleksandrovich - No. 2014103070/14; declared 30.01.2014; published 27.04.2015. - Bulletin No. 12).

The disadvantages of this method include:

1. The lack of preliminary calculation of the required size and shape of the transplant for each patient, which will not allow for optimal correction of the deformity and improvement of the foot function and, at the same time, increases the risk of deformity recurrence, since the method involves autotransplantation of the talocalcaneal joint area in all patients with a cylindrical spongy-cortical bone fragment of the same size with a diameter of up to 1 cm, which will not eliminate severe deformity or will lead to its recurrence.

2. Also, this method does not use a landmark for optimal fixation of the foot bones. During the operation, the fixing pins and screws are inserted under the control of an electron-optical converter (EOC) in one sagittal plane. The absence of an external landmark for guiding the pins and screws in the frontal plane can contribute to their medial or lateral displacement, weak fixation of the graft and instability of the screws, and will also cause the need to re-insert the pins (screws) with additional EOC control and with an increase in the dose of X-ray radiation and the time of the operation.

3. The mini-accesses to the talocalcaneal joint used in the method do not allow for reliable visualization of the cartilaginous articular surfaces of the calcaneus and talus bones, their high-quality processing and removal, which after the autograft is inserted will lead to a disruption of its osseointegration, relapse of pain syndrome, osteoarthrosis, deformation, and disruption of support and walking function.

The closest in technical essence to the proposed method is a method for correcting post-traumatic valgus deformity of the rear part of the foot, which includes performing external access to the subtalar joint cavity, removing the cartilaginous surfaces of the talus and calcaneus in the area of the posterior articular facet of the subtalar joint, introducing a bioresorbable cylindrical implant from Stryker into the cavity of the sinus tarsi to wedge the bones of the rear part of the foot to the required distance and eliminate the valgus deformity. A bone autograft of the required size, taken from an additional 3 cm long incision in the lower third of the tibia on the side of the operation, is introduced into the resulting cavity in the area of the posterior articular facet of the calcaneus. Fixation of the autograft is performed with two cannulated screws inserted in parallel from the area of the calcaneal tubercle into the body of the talus ([3]) Method for Correcting Post-traumatic Valgus Deformity of the Rear Part of the Foot: Pat. 2405485, Russian Federation; IPC A61B 17/56 / R.M. Tikhilov, N.A. Koryshkov, A.M. Privalov; applicant and patent holder Federal State Institution “Russian Research Institute of Traumatology and Orthopedics named after R.P. Vreden of the Federal Agency for High-Tech Medical Care” (FGU “R.P. Vreden RNIITO of Rosmedtekhnologii”) - No. 2009116112/14; declared 27.04.2009; published 10.12.2010. - Bulletin No. 34).

However, the closest known method has the following significant disadvantages, namely:

1. In this method, as in other similar methods, there is no description of the calculations of the required shape and size of the bone graft for a specific patient, which would allow the production of an “optimal” size and shape of the graft, as a result of which successful arthrodesis of the talocalcaneal joint can be performed to completely eliminate the deformation and reduce the risk of relapse.

2. In the prototype, wedging of the talus and calcaneus is performed without calculating the required distance between them and, accordingly, the required implant size is not established. The lack of a description of precise calculations and reference points complicates the practical effective application of the method. The use of a bioresorbable implant from Stryker for wedging of the bones of the rear part of the foot is irrational due to the presence of special surgical instruments - distractors, in addition, it is an additional artificial implant that has the probability of migration and infection.

3. Performing additional access and harvesting the tibia on the side of the operation for autotransplantation into the subtalar joint cavity increases the duration and trauma of the operation, which also increases the risk of infection of postoperative wounds.

4. When performing the fixation stage in the prototype, as in other methods, the location of the external landmark is not determined, which can technically hinder the parallel implementation of fixing elements and, due to the need to repeat them, increases the time of the operation, the radiation dose, and also contributes to unstable fixation of the transplant, failure of arthrodesis and recurrence of the deformation.

The objective of the claimed invention is to develop a method for surgical treatment of hallux valgus.

The technical result of the claimed invention "Method for Correcting Rearfoot Deformation" is to increase the effectiveness of patient treatment by eliminating rearfoot deformity, fully restoring foot function, preventing recurrence of deformity, and relieving pain.

The technical result is achieved in that the method of surgical treatment of valgus deformity of the rear part of the foot includes access along the outer surface of the foot in the area of the talocalcaneal joint, removal of the cartilaginous surfaces from the talus and calcaneal bones in the area of the posterior articular facet of the talocalcaneal joint, separation of the talus and calcaneal bones, impaction of a bone graft into the cavity of the talocalcaneal joint and its fixation between the calcaneal and talus bones with two cannulated screws.

The distinctive techniques of the proposed method are that before the operation, functional multispiral computed tomography is performed with 3D reconstruction of the entire model of the deformed foot with the distal third of the tibia and individual models of the talus and calcaneus bones, the relative position of individual models of the talus and calcaneus bones is changed until the values of the reference norm of the studied talo-tarsal and tibiocalcaneal angles are achieved.

The differences of the claimed method also consist in the fact that in the cavity between the talus and calcaneus, namely in the area of the posterior facet of the talocalcaneal joint, a geometric figure with six rectangular sides is drawn, the height of which is equal to the height of the cavity, while the height of the outer side of this geometric figure is increased by 6 mm. According to the new contours of the figure, an MSCT model of the transplant is created.

The main difference of the proposed method is that before the operation, an allograft is made in a shape and size corresponding to its MSCT model.

The distinctive techniques of the claimed method also include the fact that on the tomogram of the entire foot in the frontal plane, the first line of the ankle joint is drawn, 1.5 cm is stepped down from it and a second line is drawn parallel to it, on which the first point is marked in the middle of the width of the talus, which is a reference point for the optimal placement of fixing screws, and the second point is on the outer border of the tendon of the anterior tibial muscle, after which the distance between them is measured.

Another difference from known methods is that the resection of the articular surfaces of the talus and calcaneus is performed to a depth of no more than 2 mm, while the distance between the talus and calcaneus along the outer edge of the foot is equal to the height of the outer side of the transplant plus 2 mm.

Another distinctive feature of the technique is that after the allograft is impacted into the cavities of the talocalcaneal joint, the fixation stage begins with marking two parallel lines on the skin along the anterior surface of the limb: the first in the projection of the ankle joint, the second 1.5 cm distally. After this, on the second line outward from the outer border of the tendon of the anterior tibial muscle, the distance between the first and second points, previously measured by the tomogram, is measured and a point located in the projection of the middle of the width of the talus is marked. Two cannulated screws are inserted in the direction of this point, fixing the allograft.

The conducted patent information research on subclass A61B 17/56 and the analysis of scientific and medical information reflecting the existing level of technologies for correction of the rear foot deformity did not reveal identical technologies. From the comparative analysis of the claimed technical solution and known methods, the conclusion was made that the proposed method is distinguished by the above-mentioned techniques and, therefore, meets the patentability criterion of the invention "novelty".

Based on the analysis of clinical material, the authors of the claimed method identified the following advantages:

Preliminary performance of functional multispiral computed tomography (fMSCT) of the patient's deformed foot and the use of computer modeling programs allows for the creation of an MSCT model of a bone graft, according to which a graft of the appropriate shape and size is made from allograft bone before the operation, which helps to reduce the time of the operation and its trauma, and reduces the risk of infectious complications associated with additional intervention to collect the graft and model it according to the required shape and size.

Changing the relative position of individual MSCT models of the talus and calcaneus until the values of the studied angles of deformation of the rear part of the foot (talometatarsal and tibiocalcaneal) reach the reference norm; drawing in the cavity between the talus and calcaneus in the area of the posterior facet of the talocalcaneal joint of a geometric figure with six rectangular sides in height exactly corresponding to the height of the cavity and increasing the outer side of the figure by 6 mm, allows modeling an individual transplant in shape and size, which during the operation will allow performing bone grafting of the cavity of the talocalcaneal joint, carry out the necessary correction and completely eliminate the deformation of the rear part of the foot.

When creating a MSCT model of the transplant, the height of the outer side of the figure is increased by 6 mm, since after resection of the articular surfaces of the talus and calcaneus, the height of the cavity in the area of the posterior facet of the talocalcaneal joint will increase by 4 mm, and in the postoperative period, due to the expected natural bone impaction, the height of the transplant will decrease by 2 mm.

This helps prevent loss of correction, recurrence of hindfoot deformity and pain syndrome.

The authors of the claimed method have established that resection of the articular surfaces of the talus and calcaneus in the area of the posterior facet of the talocalcaneal joint to a depth of no more than 2 mm is sufficient to remove articular cartilage and achieve osseointegration of the transplant, and also contributes to maximum preservation of the volume and height of the calcaneus and talus, which plays an important role in restoring foot function.

Marking on the MS tomogram a line in the ankle joint area and a second line parallel to it, stepping down 1.5 cm, marking on it the first point in the middle of the width of the talus and the second point - on the outer border of the tendon of the anterior tibial muscle, measuring the distance from the first to the second point, which is individual for each patient, allows you to accurately mark the middle of the width of the talus on the operating table, as a reference point for optimal placement of fixing screws, which ensures strong and stable fixation of the transplant between the calcaneus and talus bones.

Surgical treatment using the proposed method allows for the complete elimination of valgus deformity of the hindfoot and restoration of its function, relief of pain, prevention of loss of correction and development of relapse of the deformity, reduction of the time of surgery and its trauma, and reduction of the risk of infectious complications.

From the above it follows that the proposed method for correcting the deformation of the rear part of the foot meets the invention criterion of “inventive step”.

The proposed method is intended for use in practical healthcare in orthopedic and traumatology clinics during surgical treatment of foot pathologies and meets the invention criterion of “industrial applicability”.

The method of correcting the deformation of the hindfoot is explained by illustrations, which show:

Fig. 1 - diagram of the image of a complete 3D model of the foot with the distal third of the tibia and individual models of the foot bones on an MS tomogram;

Fig. 2 - diagram of the marking of the talometatarsal angle in the sagittal plane on the MS tomogram;

Fig. 3 - diagram of the marking of the tibiocalcaneal angle in the frontal plane on the MS tomogram;

Fig. 4 - diagram of the image of the geometric figure between the talus and calcaneus bones in the area of the posterior facet of the talocalcaneal joint on the MS tomogram;

Fig. 5 - diagram of MSCT model of bone transplant with six rectangular sides - geometric figure: outer (A), inner (B), lower (C), upper (G), anterior (D), posterior (E); Fig. 6 - diagram of marking lines and points on MS tomogram of integral model of foot with distal third of tibia in frontal plane for determination of location of landmark for optimal placement of fixing screws;

Fig. 7 - diagram of marking lines and points in the projection of the middle of the width of the talus on the skin along the anterior surface of the foot and ankle joint.

Fig. 8 - photo of the right foot of patient S. before surgery, rear view;

Fig. 9 - diagram of marking the angles of deformation of the hindfoot on the MS tomogram of patient S. before surgery: a - talometatarsal angle, b - tibiocalcaneal angle;

Fig. 10 - photo of the right foot of patient S. 1 year after surgery, rear view;

Fig. 11 - image of two fixing screws in the frontal plane on the MS tomogram of the foot of patient S. 1 year after the operation;

Fig. 12 - diagram of the marking of the angles of deformation of the rear part of the foot on the MS tomogram of patient S. 1 year after the operation: a - talometatarsal angle, b - tibiocalcaneal angle;

To clarify the above illustrations, we present a decoding of the symbols used:

1 - a complete model of a deformed foot;

2 - distal third of the leg;

3 - talus;

4 - calcaneus;

5 - anatomical axis of the talus 3;

6 - first metatarsal bone;

7 - anatomical axis of the first metatarsal bone;

8 - talometatarsal angle;

9 - anatomical axis of the calcaneus 4;

10 - tibia;

11 - anatomical axis of the tibia;

12 - tibiocalcaneal angle;

13 - geometric figure;

14 - MSCT model of the transplant;

15 - ankle joint area;

16 - the first line in the ankle joint area;

17 - second line;

18 - the first point in the middle of the width of the talus 3;

19 - tendon of the anterior tibial muscle;

20 - the second point on the outer border of the tendon of the anterior tibialis muscle;

21 - fixing screws.

The essence of the proposed “Method for Correcting Rearfoot Deformity” is as follows:

To eliminate hallux valgus, a model of the required bone graft is created and the location of the landmark is calculated for optimal placement of the fixing screws.

Before the operation, functional multispiral computed tomography (fMSCT) of the patient's deformed foot is performed from the plantar surface to the distal third of the leg, simulating a static load by the pressure of the support platform on the soles of the feet ([4] Ternovoy, S.K. Methodology of functional multispiral computed tomography in the diagnosis of flatfoot in adults / S.K. Ternovoy, N.S. Serova, A.S. Belyaev [et al.] // Russian Electronic Journal of Radiation Diagnostics. - 2017. - No. 1 (7). - P. 94-100).

The obtained tomograms are loaded into a 3D modeling program, where a reconstruction of the entire model of the patient's deformed foot (1) with the distal third of the tibia (2) and individual models of the talus (3) and calcaneus (4) bones is performed (see appendix to the description of the application, Fig. 1). All models are saved as separate files and loaded into a program that allows for the mutual movement of individual bone models.

To obtain a transplant model, separate models of the talus (3) and calcaneus (4) bones are compared with similar bones in the integral foot model. On the obtained image in the sagittal plane, the anatomical axis (5) of the talus (3) and the axis (7) of the first metatarsal bone (6) are drawn and the value of the talo-primometatarsal angle (8) is determined (see the appendix to the description of the application, Fig. 2). In the frontal plane, the axis (9) of the calcaneus (4) and the axis (11) of the tibia (10) are drawn and the value of the tibiocalcaneal angle (12) is determined (see the appendix to the description of the application, Fig. 3). Then, the relative position of the individual models of the talus and calcaneus bones is changed so that the values of the studied angles of deformation of the rear part of the foot (8 and 12) correspond to the reference norm, the image of the integral model of the foot and lower leg (1 and 2) is deleted, leaving the resulting image of the individual models of the talus (3) and calcaneus (4) bones. In the cavity between the talus (3) and calcaneus (4) bones in the area of the posterior facet of the talocalcaneal joint, a geometric figure (13) with six rectangular sides is drawn so that the contours of the figure in height exactly correspond to the height of the cavity (see appendix to the description of the application, Fig. 4). After this, the image of the figure is saved as a separate file, to prevent the loss of deformation correction, the height of the outer side of the figure is increased by 6 mm, new contours of the figure are marked and an MSCT model of the required transplant (14) is obtained with the sides: outer (A), inner (B), lower (B), upper (G), front (D) and back (E) (see appendix to the description of the application, Fig. 5). Before the operation, an allograft is made of bone in a shape and size corresponding to its MSCT model.

The next step is to draw the first line (16) in the ankle joint area (15) on the MS tomogram of the integral model of the foot and lower leg in the frontal plane, step back 1.5 cm downwards from it and draw the second line (17) parallel to it, on which the first point (18) is marked in the middle of the width of the talus (3), which is a reference point for the optimal placement of the fixing screws. At the intersection of the second line (17) with the outer border of the tendon of the anterior tibial muscle (19), the second point (20) is marked. The distance from the first (18) to the second (20) point is measured to accurately determine the middle of the width of the talus on the operating table (see the appendix to the description of the application, Fig. 6).

Then, surgical correction of the rear foot deformity is performed, for which purpose access is performed along the outer surface of the foot to the talocalcaneal joint. Using the Hinterman distractor, the talus and calcaneus are separated, in the area of the posterior facet of the talocalcaneal joint, the articular surfaces of the talus and calcaneus are resected to a depth of no more than 2 mm, after which the distractor is installed in such a position that the distance between the talus and calcaneus along the outer edge of the foot is equal to the height of the outer side (A) of the transplant plus 2 mm. An allograft made in advance according to the MSCT model (14) is impacted into the cavity of the talocalcaneal joint.

After removing the distractor, we proceed to the stage of graft fixation, which begins with external marking. Two parallel lines are drawn on the skin along the anterior surface of the limb: the first (16) in the projection of the ankle joint (15), the second (17) - 1.5 cm distally. On the second line (17), outward from the outer border of the tendon of the anterior tibial muscle (19), the distance previously measured according to the MS tomogram (between points 18 and 20) is measured and a point (18) is marked, which is located in the projection of the middle of the width of the talus (see the appendix to the description of the application, Fig. 7). In the sagittal plane, two needles are passed parallel through the calcaneus, then the graft, to the internal cortical plate of the talus in the direction of point (18) of the middle of the width of the talus, after which two cannulated screws are passed along the needles and the graft is securely fixed between the calcaneus and talus bones.

The proposed method of correcting the deformity of the hindfoot is illustrated by a clinical example:

Patient S., 51 years old, was hospitalized in the INCST clinic for surgical treatment with the diagnosis: Post-traumatic valgus deformity of the posterior part of the right foot. Deforming arthrosis of the talocalcaneal joint stage 3, pain syndrome.

History: On January 28, 2023, as a result of falling from a roof, she sustained an open fracture of the right calcaneus with displacement. At the local healthcare facility, primary surgical treatment of the wound and plaster immobilization were performed. The wound healed by primary intention, the plaster cast was removed after 4 weeks, walking was allowed. Over time, pain in the foot developed, which intensified when walking and wearing shoes. The patient noticed a deformation of the heel and "wearing down" of shoes on the inner surface of the right foot. Upon examination, valgus deformity of the calcaneus of the right foot was determined (see appendix to the description of the application, Fig. 8), visible deviation of the calcaneus outward. With active and passive movements of the foot - pain in the projection of the talocalcaneal joint on the outer side of the foot.

Before the operation, functional multispiral computed tomography (fMSCT) of the right foot was performed. The initial value of the talometatarsal angle was 22 degrees, the tibiocalcaneal angle was 15 degrees, which exceeded the reference norm and objectively confirmed the presence of hallux valgus of the right foot in the patient (see appendix to the description of the application, Fig. 9, a, b).

Before the operation, MSCT modeling of the transplant and its production from allograft bone was performed, as well as calculation of the location of the landmark for optimal placement of two fixing screws.

On October 10, 2023, surgical correction of the hindfoot deformity was performed using the proposed method.

The postoperative period was uneventful. Plaster immobilization of the foot was performed for 8 weeks, and courses of exercise therapy and lymphatic drainage massage were also conducted.

One year after the surgery, the patient has no complaints, there is no pain in the right foot, she moves with a full load on the right foot, there is no gait disturbance. Complete elimination of the deformity of the hindfoot was established (see the appendix to the description of the application, Fig. 10). According to the control fMSCT study, good consolidation of the talus and calcaneus with the bone graft, optimal and stable position of the fixing screws (see the appendix to the description of the application, Fig. 11), as well as compliance of the values of the angles of deformation with normal values were determined: talo-arthrometatarsal angle - 10 degrees, tibiocalcaneal angle - 1 degree (see the appendix to the description of the application, Fig. 12, a, b). The patient was satisfied with the treatment result, elimination of the deformity, pain syndrome, restoration of normal weight-bearing ability of the right foot.

Seven patients with posttraumatic valgus deformity of the hindfoot were operated on using the proposed method. When evaluating the results obtained one year after the operation, it was determined that the hindfoot deformity had been eliminated, pain syndrome had been relieved, the bone graft had been consolidated without displacement, there was no screw migration, the foot function had been restored, and physical activity had been increased.

Thus, the proposed "Method for Correcting Rearfoot Deformity" allows for complete elimination of rearfoot deformity by preliminary creation of an MSCT model of the required bone graft and its manufacture from allograft bone in strict accordance with the model, both in shape and size, achieving strong fixation of the graft between the calcaneus and talus bones, relieving pain, preventing loss of correction and recurrence of deformity, reducing trauma and duration of surgery, risk of infectious complications, and restoring foot function.

Sources of information taken into account:

1. Method of arthrodesis of the subtalar joint: Patent. 2164389, Russian Federation; IPC A61B 17/56 / V.V. Dolgopolov, A.S. Sati; applicant and patent holder Russian Research Institute of Traumatology and Orthopedics named after R.P. Vreden - No. 99110124/14; declared. 12.05.1999; published. 27.03.2001. - Bulletin No. 9.

2. Minimally invasive arthrodesis of the subtalar joint: Patent. 2549297, Russian Federation; IPC A61B 17/56 / N.A. Koryshkov, A.S. Khodzhiev, V.T. Zeynalov, A.M. Dzyuba, A.P. Khapilin, K.A. Sobolev; applicants and patent holders: Nikolay Aleksandrovich Koryshkov, Artur Safarovich Khodzhiev, Vadim Tofikovich Zeynalov, Aleksey Mikhailovich Dzyuba, Anton Pavlovich Khapilin, Kirill Aleksandrovich Sobolev - No. 2014103070/14; declared 30.01.2014; published 27.04.2015. - Bulletin No. 12.

3. Method for correction of post-traumatic hallux valgus: Patent 2405485, Russian Federation; IPC A61B 17/56 / R.M. Tikhilov, N.A. Koryshkov, A.M. Privalov; applicant and patent holder Federal State Institution “Russian Research Institute of Traumatology and Orthopedics named after R.P. Vreden of the Federal Agency for High-Tech Medical Care” (FGU “R.P. Vreden RNIITO of Rosmedtekhnologii”) - No. 2009116112/14; declared 27.04.2009; published 10.12.2010. - Bulletin No. 34.

4. Ternovoy, S.K. Methodology of functional multispiral computed tomography in diagnostics of flat feet in adults / S.K. Ternovoy, N.S. Serova, A.S. Belyaev [et al.] // Russian Electronic Journal of Radiation Diagnostics. - 2017. - No. 1 (7). - P. 94-100.

Claims (1)

A method for correcting a deformity of the hindfoot, including access along the outer surface of the foot in the area of the talocalcaneal joint, removal of the cartilaginous surfaces from the talus and calcaneus in the area of the posterior articular facet of the talocalcaneal joint, separation of the talus and calcaneus, impaction of a bone graft into the cavity of the talocalcaneal joint and its fixation between the calcaneus and talus bones with two cannulated screws, characterized in that functional multispiral computed tomography with 3D reconstruction of a complete model of the deformed foot with the distal third of the tibia and individual models of the talus and calcaneus bones is performed before the operation, then the relative position of the individual models of the talus and calcaneus bones is changed until the reference norm values of the studied talometatarsal and tibiocalcaneal angles are achieved, after which in the cavity between the talus and calcaneus bones, namely in the area of the posterior facet of the talocalcaneal joint, a geometric figure with six rectangular sides is drawn, the height of which is equal to the height of the cavity, while the height of the outer side of this geometric figure is increased by 6 mm, new contours of the figure are marked, along which an MSCT model of the transplant is created; before the operation, an allograft is made in the shape and size corresponding to its MSCT model, then on the tomogram of the whole foot in the frontal plane, the first line of the ankle joint is drawn, they retreat from it downwards by 1.5 cm and a second line is drawn parallel to it, on which the first point is marked in the middle of the width of the talus, which is a reference point for the optimal placement of fixing screws, and the second point is on the outer border of the tendon of the anterior tibial muscle and the distance between them is measured; for surgical correction of the deformity of the hindfoot, the Hinterman distractor is used to separate the talus and calcaneus bones, and in the area of the posterior facet of the talocalcaneal joint, the articular surfaces of the talus and calcaneus bones are resected to a depth of no more than 2 mm, the distractor is used to achieve a distance between the talus and calcaneus along the outer edge of the foot equal to the height of the outer side of the transplant plus 2 mm, then the allograft is impacted into the cavity of the talocalcaneal joint, and the stage of its fixation begins with marking two parallel lines on the skin along the anterior surface of the limb: the first - in the projection of the ankle joint, the second - 1.5 cm distally, after which on the second line outward from the outer border of the tendon of the anterior tibial muscle, the distance between the first and second points, previously measured according to the tomogram, is measured and a point located in the projection of the middle of the width of the talus is marked, and two cannulated screws that fix the allograft.