RU2547252C1 - Method for preoperative planning of corrective osteotomy of shin bones for bowed legs correction - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: method involves recording a teleroentgenogram of both legs, including hip and ankle joints of a patient standing so that his/her legs touching each other at the level of medial malleoli; lower legs are contoured on the teleroentgenogram. A line passing through the centre of pubic symphysis and the most projecting point of an inner contour of the shin bone at the level of an inner shin-bone (SB) ankle is marked to divide the roentgenogram in two. Each of them is turned about the centre of femoral (F) head until the most projecting point of the inner contour of femur is placed on a line perpendicular to a bispinal line. That is followed by separating three complexes, wherein the complex I comprises the outer and inner contours of the extremity above the level of expected osteotomy, femoral skiagram and a proximal fragment of the SB. The complex II includes the inner contour of the shin bone below the osteotomy level and skiagram of a distal fragment of the SB. The complex III comprises the outer contour of the shin bone and fibular bone (FB) skiagram. valgisation and medialisation of the distal fragments of the SB and FB bringing down are simulated in stages. When simulating the valgisation, the complexes II and III are turned about an intersection point of an outer cortical layer of the SB and a line of the expected osteotomy until the most projecting point of the inner contour of the shin bone on the line perpendicular to the bispinal line. An angle, which both complexes are turned at is equal to a value of the expected valgisation. When simulating the medialisation of the distal fragments of the SB, the complex II is rotated about a point matched to the most distal point of the distal tibiofibular syndesmosis before the most projecting point of the inner contour of the shin bone is placed on a line perpendicular to the bispinal line. A distance between the intersection point of the inner contour of the shin bone with a mechanical axis of the SB before and after rotation of the complex II is equal to a value of the expected medialisation. When simulating FB bringing down, the complexes II и III are moved downwards at a value of the expected distraction. The complex III is rotated about the most distal point of the distal tibiofibular syndesmosis until the most proximal point of the proximal tibiofibular joint is placed on the outer cortical layer of the SB.

EFFECT: accurate planning of the required value of valgisation, varisation or medialisation of bone fragments to provide an ideal leg shape, planning the required value of bringing the fibular bone down to preserve the shin bone width; ensuring the pre-operative assessment of the impact of various surgical options on the biomechanical properties of the lower extremity.

22 dwg, 1 tbl, 1 ex

Description

The invention relates to medicine, namely to orthopedics and plastic surgery, and can be used to plan surgical interventions to correct the shape of the legs.

With the so-called They touch the “ideal shape of the legs” at three points located on the inner contours of both limbs: point I is located at the level of the distal metaepiphyses of the femur, point II is at the border between the upper and middle third of the tibia diaphysis, point III is at the level of the ankles (Figure 1) [Aesthetic and reconstructive surgery of the lower extremities / Ed. A.A. Artemieva. M.: GEOTAR-Media, 2008.248 s.].

When correcting the shape of the legs, an osteotomy (intersection) of the tibia is produced. Fixation of bone fragments is performed in an external fixation apparatus. Correction of the position of bone fragments is often done gradually, less often - simultaneously. The distal fragment of the tibia is subjected to the following types of movements: valgization, medialization (movement of the fragment of the inside) and elongation (distraction) [Bagirov AB, Rudkovsky AA, Kafanov AV Aesthetic orthopedics of the legs // Kremlin medicine. Clinical Herald. 2002. No4. S.50-52; Barinov A.S., Vorobev A.A., Zaitsev S.S. Cosmetic aspects of the operative correction of dysplastic varus deformities of the lower extremities // Clinical Medicine. 2010. No4. S.57-60; Egorov M.F., Chernov A.P., Nekrasov M.S. Orthopedic cosmetology / M.: Publishing Center "Fedorov", 2000.192 p .; Ilizarov G.A. Methods of modeling the form of the tibia and its lengthening / G.A. Ilizarov, A.G. Kaplunov, V.I. Shevtsov et al. / Orthopedics, traumatology and prosthetics. 1979. No. 11. S.28-31; Kaplunov O.A., Kaplunov A.G., Shevtsov V.I. Cosmetic correction of the shape and length of the legs / M .: GEOTAR-Media, 2010.160 s .; Marker N.A. Prediction of tactics and results of orthopedic cosmetic correction of lower leg deformity [dis. ... cand. honey. sciences]. Kurgan: Federal State Institution Scientific Center of the World Trade Organization named after Acad. G.A. Ilizarova; 2009; Aesthetic and reconstructive surgery of the lower extremities / Ed. A.A. Artemieva. M.: GEOTAR-Media, 2008.248 s. (Library of a specialist doctor. Orthopedics, surgery); Solomin L.N. The Basic Principles of External Fixation using the Ilizarov Device / Milan: Springer-Verlag Italia, 2008. 357 p.].

To correct deformation of the tibia in the frontal plane, Coventry preoperative planning methods are known [Coventry M.V., Ilstrup D.M., Wallrichs S.L. (1993): Proximal tibial osteotomy. A critical long-term study of eighty-seven cases. J Bone Joint Surg Am 75, 196-201] (FIGS. 2 and 3), Miniaci [Miniaci A., Ballmer E.T., Ballmer P.M., Jakob R.P. (1989): Proximal tibial osteotomy. A new fixation device. Clin Orthop Relat Res 246, 250-259.] (FIG. 4), Lobenhoffer [Lobenhoffer P., Agneskirchner J.D., Gala M. Kniegelenknahe Osteotomien. - Thieme, 2007. - 161 p.] (Fig. 5), Paley [Paley D. Principles of deformity correction / New York: Springer-Verlag, 2003. 806 p.] (Fig. 6), according to which preoperative planning is performed based on the study of the deviation of the mechanical axis of the lower limb (including following the Fujisawa criterion [Fujisawa Y., K. Masuhara, S. Shiomi (1979): The effect of high tibial osteotomy on osteoarthritis of the knee. An arthroscopic study of 54 knee joints. Orthop Clin Noth Am 10, 585-608]), tibiofemoral angle, proximal and distal mechanical angles of the tibia on a teleradiograph [Orlyansky V., Golovakha M., Schwabus R. Corrective osteotomies in the region Deer joint / Dniproperovsk: Thresholds, 2009. 159 p.]. The direction of deviation and its magnitude (normal values are 4.1 ± 4 mm inwards (Bhave et al. By Paley [Paley D. Principles of deformity correction / New York: Springer-Verlag, 2003. 806 p.]) Determine the type of deformation (varus or valgus) and the degree of its severity. Planning (modeling) of the correction result is carried out in the form of an application or in a graphical editor by turning the skygram of the distal tibia fragment to the position that provides the correct values of the studied values. the location of the bone fragments of the tibia (planning according to Lobenhoffer, Paley), the angle of the planned correction - the required angle of rotation (valgization) of the distal fragment of the tibia (planning according to Coventry, Miniaci, Lobenhoffer, Paley), the value of the opening / closing of the wedge with open / closed osteotomy (planning by Lobenhoffer).

The disadvantage of these methods is the inability to predict the shape of the legs (their silhouette) after correction. The reasons for this are:

1. The use of only skiagrams of the femur and tibia, ignoring the silhouette (contour) of the legs in preoperative planning.

2. Ignoring the tibia skiagram. It is known that the shape of the external contour of the lower leg depends on the position of the fibula or its fragments [Aesthetic and reconstructive surgery of the lower extremities / Ed. A.A. Artemieva. M .: GEOTAR-Media, 2008.248 s .; Modeling the shape and thickening of the lower leg: Method. recommendations / G.A. Ilizarov, V.N. Shevtsov, V.D. Shatokhin. Kurgan, 1980. - P.17].

Currently, the Internet presents programs that allow users (doctors and potential patients) to perform modeling of the shape of the legs using photographs [http://legscorrection.ru/prog.php (accessed: 01/29/13)] (Fig. 7 ), http://plastio.ru (date of treatment: 01/29/13) (Fig. 8).

Similar software O.A. is released on the CD Kaplunov et al. [Kaplunov O.A., Kaplunov A.G., Shevtsov V.I. Cosmetic correction of the shape and length of the legs. The application on the CD-ROM program "Correction of the shape of the legs" (demo version) / M .: GEOTAR-Media, 2010] (Fig.9).

When using them in the patient’s photo in a standing position with legs brought together, the user should mark the “reference points” - the centers of the hip and ankle joints and the points located on the inner surfaces of the lower legs at the level of the alleged osteotomy [O. Kaplunov, A.G. Kaplunov. Shevtsov V.I. Cosmetic correction of the shape and length of the legs. The application on the CD-ROM is the program “Correction of the shape of the legs” (demo version) / M .: GEOTAR-Media, 2010]. The result of planning is a photograph with a changed contour of the patient’s legs - the silhouette of each leg is transformed (“bends”) in such a way that the anchor points marked on the inner contours of the legs touch.

The disadvantages of this type of preoperative planning are:

1. Low accuracy, because reference points “centers of the ankle joints” and, especially, “centers of the hip joints” can only be determined in the photograph approximately.

2. The inability to predict the relationship of reference lines and angles of the lower limb (anatomical and mechanical axes and angles, deviation of the mechanical axis) [Solomin L.N. The Basic Principles of External Fixation using the Ilizarov Device / Milan: Springer-Verlag Italia, 2008.357 p .; Paley D. Principles of deformity correction / New York: Springer-Verlag, 2003. 806 p.] After correction of the shape of the legs.

The technical result of the invention is the ability to accurately plan the required value of valgization (or variation), medialization of distal fragments of the tibia of the proximal tibial-fibular joints, the most protruding point of the inner contour of the tibia at the level of the inner ankle of the tibia, the most distal point of the distal tibial syndesmosis, the most distal point of the fibula bones, the intersection of the outer edge of the radiograph and the continuation of the segment, image vannogo the most distal point of the distal tibiofibular syndesmosis and the most distal point of the fibula; then mark the line passing through the center of the pubic symphysis and the most protruding point of the inner tibia contour at the level of the inner ankle of the tibia, and two parts of the radiograph are obtained, then each of them is turned around the center of the femoral head until the most protruding point of the inner thigh contour is superimposed on the line, perpendicular to the bispinal line, after which three complexes are distinguished, and complex I includes the external and internal contours of the limb above the level of the proposed osteotomy , skiagrams of the femur and the proximal fragment of the tibia, complex II includes the inner contour of the tibia below the level of the osteotomy and the skiagram of the distal fragment of the tibia, complex III includes the external contour of the tibia and the skiagram of the fibula, after which complexes II and III rotate around the point of intersection of the outer cortical layer the tibia and the line of the alleged osteotomy until the most protruding point of the inner contour of the lower leg at the level of the inner ankle is superimposed on the line, perp the dicular bispinal line, to model valgization, complex II is rotated around the point corresponding to the most distal point of the distal tibiofibular syndesmosis until the most protruding point of the inner contour of the tibia is superimposed on the line perpendicular to the bispinal line to simulate the medialization of distal fragments of the tibia, complexes of II and III bones for ensuring the “ideal shape of the legs”, as well as planning the necessary amount of reduction of the fibula to maintain the width of the lower leg; the possibility of assessing before surgery the effect of various options for its execution on the biomechanics of the lower limb by examining the alleged relationships of reference lines and angles. This study is performed according to Paley [Paley D. Principles of deformity correction / New York: Springer-Verlag, 2003. 806 p.].

The result of the invention is achieved by determining the necessary movements of the distal fragments of the tibia and fibula using an application or in a graphical editor. In the position of the patient, standing so that the legs touch at the level of the medial ankles, a tele-radiograph is obtained, the field of which captures both legs of the patient with the inclusion of the hip and ankle joints, on which the contour of the lower extremities is marked, a line is drawn through the middle of the pubic symphysis, perpendicular to the bispinal line, then draw a line perpendicular to the mid-pituitary line of the tibia; then point the center of the femoral head, the most protruding point of the inner contour of the thigh, the intersection of the inner contour of the tibia and the line perpendicular to the mid-pituitary line of the tibia, the most protruding point of the inner contour of the tibia at the border between the upper and middle third of the tibia, the intersection of the outer cortical layer the tibia and the line perpendicular to the mid-pituitary line of the tibia, the most proximal point of proximal pain of the tibial-fibular joint, the intersection of the outer edge of the radiograph and the continuation of the segment formed by the point of intersection of the outer cortical layer of the tibia with a line perpendicular to the mid-pituitary line of the tibia, and the most proximal point is moved downward by the magnitude of the proposed distraction, complex III is rotated around the most distal point syndesmosis before application of the most proximal point of the proximal tibial-fibular joint outer cortical bone of the tibia for modeling downmix fibula.

The figures depict:

Figure 1 - ideal shape of the legs according to A.A. Artemyev; the legs touch at three points located on the inner contours of both limbs: point I is located at the level of the distal metaepiphyses of the femur, point II is at the border between the upper and middle third of the tibia diaphysis, point III is at the level of the ankles [Aesthetic and reconstructive surgery lower limbs / Ed. A.A. Artemieva. M.: GEOTAR-Media, 2008.248 s.].

Figure 2 - the method of preoperative planning correction of deformation of the tibia according to Coventry using the anatomical axis (line 1 is the anatomical axis of the femur, line 2 is the anatomical axis of the tibia, angle 1-2 is the preoperative anatomical angle of the varus deformity (AC), angle 2- 3 - planned correction angle (P)) [Coventry M.V., Ilstrup D.M., Wallrichs SL (1993): Proximal tibial osteotomy. A critical long-term study of eighty-seven cases. J Bone Joint Surg Am 75, 196-201].

Figure 3 - the method of preoperative planning correction of deformation of the tibia according to Coventry using the mechanical axis (line 1 - the mechanical axis of the thigh, line 2 - the mechanical axis of the tibia, angle 1-2 - the preoperative mechanical angle of the varus deformity (AC), angle 2- 3 - planned correction angle (P)) [Coventry M.V., Ilstrup D.M., Wallrichs SL (1993): Proximal tibial osteotomy. A critical long-term study of eighty-seven cases. J Bone Joint Surg Am 75, 196-201].

Figure 4 - the method of preoperative planning to correct deformation of the tibia according to Miniaci: line 1 is the planned mechanical axis of the limb, line 2 connects the center of rotation of the osteotomy (point D) with the center of the ankle joint, line 3 connects point D to the end of line 1 at the point of intersection with the plane of the ankle joint, angle 2 and 3 - the desired angle for osteotomy [Miniaci A., Ballmer E.T., Ballmer PM, Jakob RP (1989): Proximal tibial osteotomy. A new fixation device. Clin Orthop Relat Res 246, 250-259].

Figure 5 - the method of preoperative planning of correction of deformation of the tibia according to Lobenhoffer: point D is the center of rotation of corrective osteotomy, line 1 connects point D with the center of the ankle joint, line 2 - point D with the center of the planned position of the ankle joint; the angle between lines 1 and 2 is the angle for corrective osteotomy [Lobenhoffer P., Agneskirchner J.D., Gala M. Kniegelenknahe Osteotomien. - Thieme, 2007. - 161 p.].

6 - methods for preoperative planning correction of deformity of the tibia according to Paley [Paley D. Principles of deformity correction / New York: Springer-Verlag, 2003. 806 p.]: MLDFA - mechanical lateral distal femoral angle (distal mechanical angle of the femur) , MRTA - medial proximal tibial angle (distal mechanical angle of the tibia), LDTA - lateral distal tibial angle (distal mechanical angle of the tibia), MAD - mechanical axis deviation (deviation of the mechanical axis), tBL - transverse bisector line (bisector of the deformation angle) , t - translation (translation), Mag - magnitude of angulation (value of angular deformation) the relationship of reference lines and angles is quoted by L. N. Solomin et al. [Determination of reference lines and angles of long tubular bones (a manual for doctors) / L. N. Solomin [et al.]. St. Petersburg: RNIITO named after R .R. Vredena, 2011. 38 p.]).

Fig.7 is a method of preoperative modeling of the shape of the legs according to the photograph using the software presented on the website http://legscorrection.ru/prog.php (accessed: 01/29/13).

Fig - a method of preoperative modeling of the shape of the legs according to the photograph using the software presented on the site http://plastio.ru (date of treatment: 01/29/13).

Fig.9 is a method of preoperative modeling of the shape of the legs according to the photograph using software developed by OA Kaplunov et al. [Kaplunov O.A., Kaplunov A.G., Shevtsov V.I. Cosmetic correction of the shape and length of the legs. The application on the CD-ROM is the program “Correction of the shape of the legs” (demo version) / M .: GEOTAR-Media, 2010].

Figure 10 - stage of preoperative planning according to the proposed method: the internal contours of both legs are marked on the roentgenogram, line No. 1, perpendicular to the bispinal line, is drawn through the center of the pubic symphysis, line No. 2, perpendicular to the mid-diaphysic line of the tibial line, is drawn in the submaxillary zone (at the level of the proposed osteotomy) bones. As an example, line No. 2 is drawn only on the left tibia.

11 is a stage of preoperative planning according to the proposed method: points A, B, C, D, E, F, G, H, I, J, K are marked on the roentgenogram (as an example, points are marked on the left leg).

Fig - stage preoperative planning according to the proposed method: drawn line No. 3 through the center of the pubic symphysis and point H, which divides the radiograph into two parts.

Fig - stage preoperative planning according to the proposed method: each of the two parts of the teleentgenogram, divided by line No. 3, is rotated around points A before being superimposed on line No. 1.

Fig - stage preoperative planning according to the proposed method: for each limb there are three complexes - complex I is limited to the upper edge of the film, the outer edge of the film, the GE segment, line No. 2 (EU segment), the inner contour of the upper third of the leg and thigh, line No. 3; complex II is limited by line No. 2 (segment CE), segments EI and IK, the lower edge of the film, line No. 3 to point H, the internal contour of the limb to point C, complex III is limited by segment EG, the outer edge of the film, lower edge of the film, segments KI and IE (as an example, complexes are highlighted on the right leg).

Fig - modeling of the shape of the legs obtained by valgization of distal fragments of the tibia: complexes II and III are rotated around point E until the point H is superimposed on line No. 1.

Fig. 16 is a simulation of the shape of the legs obtained by medializing distal fragments of the tibia: complex II is rotated around point I until point D is superimposed on line No. 1.

Fig. 17 is a simulation of the shape of the legs obtained by lowering the heads of the fibula: complexes II and III are moved downward by the magnitude of the expected distraction, complex III is rotated around point I until the point F is superimposed on the outer cortical layer of the tibia.

Fig. 18 shows the shape of the legs of patient B. upon admission to the RNIITO named after R.R. Harmful.

Fig - teleradiogram of the legs of the patient B. upon admission to RNIITO them. R.R. Harmful. The analysis of the relationship of the reference lines and angles [Solomin L.N. The Basic Principles of External Fixation using the Ilizarov Device / Milan: Springer-Verlag Italia, 2008.357 p .; Paley D. Principles of deformity correction / New York: Springer-Verlag, 2003. 806 p.]: MAD D / S - 21 mm var. / 12 mm var., MTFA D / S = 6 ° var. / 3 var., MLDFA D / S = 84 ° / 85 °, mMPTA D / S = 87 ° / 84 °, mLDTA D / S - 98 ° / 95 °.

MAD (mechanical axis deviation) - deviation of the mechanical axis of the limb (normal values are 0-16 mm inside)

mTFA (mechanical tibio-femoral angle) - mechanical tibiofemoral angle (normal values - 85-90 °)

mLDFA (mechanical lateral distal femoral angle) - distal (external) mechanical angle of the femur (normal values -85-90 °)

mMPTA (mechanical medial proximal tibial angle) - proximal (internal) mechanical angle of the tibia (normal values - 85-90 °)

mLDTA (mechanical lateral distal tibial angle) - distal (external) mechanical angle of the tibia (normal values - 86-92 °)

Fig - preoperative planning, performed according to the proposed method. To ensure the desired shape of the legs, it is necessary to perform valgization of the distal fragments of the tibia (3 ° on the right, 6 ° on the left), medialization (10 mm on the right, 12 mm on the left), and 15 mm distraction on both legs. A preliminary analysis of the relationship of the reference lines and angles after correcting the shape of the legs: MAD D / S = 16 mm val. / 15 mm val., MTFA D / S = 5 ° val. / 5 val., MLDFA D / S = 84 ° / 85 °, mMPTA D / S = 90 ° / 90 °, mLDTA D / S = 88 ° / 89 °.

Fig.21 is a teleradiograph of the legs of patient B. 3 months after the dismantling of external fixation devices. The analysis of the relationship of the reference lines and angles: MAD D / S = 17 mm val. / 15 mm val., MTFA D / S = 5 ° val. / 5 val., MLDFA D / S = 84 ° / 85 °, mMPTA D / S = 90 ° / 90 °, mLDTA D / S = 88 ° / 89 °.

Fig - the shape of the legs of the patient B. (and / b No. 2745) 3 months after the dismantling of external fixation devices.

Table 1 shows the relationship of the reference lines and angles of the lower extremities before correction, during planning and after dismantling the apparatus (mechanical lateral distal femoral angle (mLDFA), proximal tibial mechanical angle (mechanical medial proximal tibial angle - mMPTA), distal mechanical angle of the tibia (mechanical lateral distal tibial angle - mLDTA), deviation of the mechanical axis (mechanical axis deviation - MAD)) [Paley D. Principles of deformity correction / New York: Springer-Verlag, 2003. 806 p .; Determination of reference lines and angles of long tubular bones (a manual for doctors) / L.N. Solomin [et al.]. SPb .: RNIITO named after R.R. Vredena, 2011. 38 p.].

The method is carried out using an application or in a graphical editor as follows: on the digitized radiograph of the lower extremities, made in a standing position so that the legs touch at the level of the medial ankles, the internal contours of the legs are noted. Through the middle of the pubic symphysis draw line No. 1, perpendicular to the bispinal line. In the submaxillary zone (at the level of the alleged osteotomy [Kaplunov OA, Kaplunov AG, Shevtsov VI. Cosmetic correction of the shape and length of the legs. M .: GEOTAR-Media, 2010. 160 p.]) Draw line No. 2, perpendicular to the mid-pituitary line of the tibia (figure 10).

On the roentgenogram of both legs, the following points are noted (Fig. 11):

A - the center of the femoral head (the center of rotation of the hip joint), around this point the leg rotates (including in the frontal plane - cast-lead);

B - the most protruding point of the inner contour of the thigh (at the level of the epicondyles of the femur - point I according to A. A. Artemyev [Aesthetic and reconstructive surgery of the lower extremities / Ed. By A. A. Artemyev. M .: GEOTAR-Media, 2008. 248 C.] figure 1). Upon reaching the ideal shape of the legs, in the position of their information, points B on both legs should coincide (Fig.13);

C is the point of intersection of the inner contour of the tibia and line No. 2;

D - the most protruding point of the inner contour of the lower leg (located at the border between the upper and middle third of the tibia - point II according to A. A. Artemyev [Aesthetic and reconstructive surgery of the lower extremities / edited by A. A. Artemyev. M .: GEOTAR -Media, 2008. 248 p.] Fig. 1), when the ideal shape of the legs is reached, in the position of their information, the D points on both legs must coincide;

E is the intersection point of the outer cortical layer of the tibia and line No. 2. Around this point, the distal fragment of the tibia rotates during valgization similarly to the rotation around point D during preoperative planning according to Miniaci and Lobenhoffer (Figs. 4 and 5) [Miniaci A., Ballmer ET, Ballmer R.M., Jakob R.P. (1989): Proximal tibial osteotomy. A new fixation device. Clin Orthop Relat Res 246, 250-259; Lobenhoffer P., Agneskirchner J.D., Gala M. Kniegelenknahe Osteotomien. - Thieme, 2007. - 161 p.];

F is the point corresponding to the most proximal point of the proximal tibiofibular articulation. This point is located on the inner cortical layer of the fibula and corresponds to the intersection point of the cortical layers of the tibia and fibula;

G is the intersection point of the continuation of the segment EF and the outer edge of the radiograph;

N - the most protruding point of the inner contour of the tibia (at the level of the inner ankle of the tibia - point III according to A. A. Artemyev [Aesthetic and reconstructive surgery of the lower extremities / Ed. By A. A. Artemyev. M .: GEOTAR-Media, 2008. 248 p.] FIG. 1), upon reaching the ideal shape of the legs, in the position of their reduction, the points H on both legs should coincide;

I is the point corresponding to the most distal point of the distal tibiofibular syndesmosis. Around this point, the fibula rotates until the F point is superimposed on the outer cortical layer of the tibia;

J is the point corresponding to the tip of the outer ankle (the most distal point of the fibula);

K is the intersection point of the continuation of the segment IJ and the outer edge of the radiograph.

On the roentgenogram, a line passing through the center of the pubic symphysis and point H is marked, thereby radiograph is divided into two parts, each of which is limited by the upper edge of the film, the limb contour and line No. 3 (Fig. 12).

Each of the parts of the roentgenogram is rotated around point A until point B is superimposed on line No. 1 (Fig. 13).

Three complexes are distinguished for each limb (Fig. 14). Complex I is bounded by the upper edge of the film, the outer edge of the film, the GE segment, line No. 2 (segment EC), the inner contour of the upper third of the leg and thigh, line No. 3. Complex II is limited by line No. 2 (segment CE), segments EI and IK, the lower edge of the film, line No. 3 to point H, the internal contour of the limb to point C. Complex III is limited by segment EG, the outer edge of the film, lower edge of the film, and KI segments and IE.

To plan the shape of the legs obtained as a result of the correction of the O-shaped, stage-by-stage simulate:

- valgization of distal fragments of the tibia (Fig. 15): complexes II and III are rotated around point E until H is superimposed on line No. 1. The angle at which both complexes are rotated is equal to the value of the planned valgization.

- medialization of distal fragments of the tibia (Fig. 16): complex II is rotated around point I until point D is superimposed on line No. 1. The distance between the position of point C before the rotation of complex II and after is equal to the value of the planned medialization.

- reduction of the fibula (Fig.17): complexes II and III are moved down by the amount of the expected distraction. Complex III is rotated around point I until the point F is superimposed on the outer cortical layer of the tibia.

After the preoperative planning is completed, using the tele-roentgenogram, it is possible to study the predicted relationships of the reference lines and angles and predict the effect of the performed surgical intervention on the mechanics of the lower extremities [Solomin L.N. The Basic Principles of External Fixation using the Ilizarov Device / Milan: Springer-Verlag Italia, 2008.357 p .; Paley D. Principles of deformity correction / New York: Springer-Verlag, 2003. 806 p.].

Clinical example. Patient V., 23 years old, was admitted to RNIITO. R.R. Harmful about the O-shaped legs on 02/14/12 (Fig. 11, 12).

Preoperative planning was performed according to the proposed method (Fig. 20): to ensure the desired shape of the legs, it is necessary to perform valgization of distal fragments of the tibia (3 ° on the right, 6 ° on the left), medialization (on the right - 10 mm, on the left - 12 mm ), 15 mm distraction on both legs.

02/15/2012, the operation of osteotomy of both tibia in the upper third, the application of external fixation devices on both legs. In the postoperative period, correction was performed according to preoperative planning (Fig. 21).

The achieved shape of the legs (Fig.22) the patient is satisfied. The relationship of reference lines and angles before correction, when planning and after dismantling the apparatus are presented in table 1 [Solomin L.N. The Basic Principles of External Fixation using the Ilizarov Device / Milan: Springer-Verlag Italia, 2008.357 p .; Paley D. Principles of deformity correction / New York: Springer-Verlag, 2003. 806 p.].

A high degree of compliance with the achieved shape of the legs (Fig.22), preoperative planning (Fig.20), performed by the proposed method, and the "ideal shape of the legs" according to A.A. Artemyev (figure 1) confirms its effectiveness.

The effectiveness of the method is also confirmed by analyzing the relationships of reference lines and angles predicted and obtained after correction of the shape of the legs (Table 1). The values of the studied quantities do not differ significantly.

Table 1 Before surgery When planning After operation MAD D / S 21 mm var. / 12 mm var. 16 mm val. / 15 mm val. 17 mm val. / 15 mm val. mTFA D / S 6 ° var. / 3 var. 5 ° val. / 5 val. 5 ° val. / 5 val. mLDFA D / S 84 ° / 85 ° 84 ° / 85 ° 84 ° / 85 ° mMPTA D / S 87 ° / 84 ° 90 ° / 90 ° 90 ° / 90 ° mLDTA D / S 98 ° / 95 ° 88 ° / 89 ° 88 ° / 89 °

Claims (1)

A method for preoperative planning of corrective osteotomy of the leg bones to correct the O-shaped legs, including determining the necessary movements of the distal fragments of the tibia and fibula by means of an application or in a graphical editor, characterized in that in the patient's position so that the legs touch at the level of the medial ankles receive a teleroentgenogram, the field of which captures both legs of the patient with the inclusion of the hip and ankle joints, on which I mark t contour of the lower extremities;
then mark the line passing through the center of the pubic symphysis and the most protruding point of the inner contour of the tibia at the level of the inner ankle of the tibia, and two parts of the radiograph are obtained;
then each of them is rotated around the center of the femoral head until the most protruding point of the inner contour of the thigh is superimposed on a line perpendicular to the bispinal line;
after which there are three complexes, where complex I includes the external and internal contours of the limb above the level of the proposed osteotomy, the sciagram of the femur and the proximal fragment of the tibia,
complex II includes the inner contour of the lower leg below the level of osteotomy and the skyagram of the distal fragment of the tibia,
complex III includes the external contour of the lower leg and the skiagram of the fibula;
then step by step model the valgization and medialization of distal fragments of the tibia and lowering of the fibula,
moreover, when modeling valgization, complexes II and III rotate around the point of intersection of the outer cortical layer of the tibia and the line of the proposed osteotomy until the most protruding point of the inner contour of the tibia at the level of the inner ankle is superimposed on a line perpendicular to the bispinal line and the angle by which both complexes rotate, equal to the value of the planned valgization;
when modeling the medialization of distal tibial fragments, complex II is rotated around a point corresponding to the most distal point of the distal tibial syndesmosis, until the most protruding point of the inner tibia contour is superimposed on the line perpendicular to the bispinal line, and the distance between the position of the point of intersection of the inner tibia contour with the mechanical axis of the tibia before the rotation of complex II and after is equal to the value of the planned medialization;
when modeling the reduction of the fibula, complexes II and III are moved downward by the value of the expected distraction, and complex III is rotated around the most distal point of the distal tibial syndesmosis until the most proximal point of the proximal tibial-fibular joint is superimposed on the outer cortical layer of the tibia.

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