RU2492809C1 - Method of estimating funnel chest deformation - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: invention relates to field of medicine, namely to orthopaedics. Method consists in determination of a set of points on body surface. Jugular incisures, upper and lower edges of funnel, funnel bottom, xiphoid process, left and right edges of funnel, points on right and left mid-axillary lines at the level of funnel bottom, points on the line of spinous processes at the level of point of upper edge of funnel, spinous processes of C₇, Th₁₂ and L₅ vertebrae, right and left posterior spines of pelvis are marked with labels on body surface. After that three-dimensional coordinates of marked points are determined and registered by means of three-dimensional scanner. Then, linear, angular and volume parameters, relative values, which characterise chest deformation and spine, their interrelation in space are calculated by means of obtained coordinates.

EFFECT: application of claimed invention makes it possible to carry out estimation of pathology by determination of three-dimensional coordinates of a set of identification points on person's body surface.

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Description

The invention relates to medicine, namely to orthopedics, and can be used in clinical practice and scientific research for monitoring age-related changes in chest deformity, making a detailed diagnosis, choosing tactics for surgical correction of chest deformities and evaluating treatment results.

A known method of assessing the severity of funnel chest deformity using x-ray examination in the front and side projections, computed tomography with image reconstruction at different levels (Dolnitsky O.V., Dirdovsky L.N. "Congenital deformities of the chest in children", 1978, p.26.). The degree of deformation is determined by the Gizycko method, for which the ratio of the smallest (a-b) and largest (c-d) sizes of the sterno-vertebral space, which are measured on the lateral radiograph, is calculated. The coefficient ratio (a-b) / (c-d) allows you to determine the degree of deformation. A value of more than 0.7 corresponds to I degree, from 0.7 to 0.5 - II degree, less than 0.5 - III degree of deformation. To determine the degree of deformation, the calculation of the Holler index is used. The index is calculated by measuring the width of the chest and dividing the measurement by the distance between the sternum and the spine. These measurements are carried out at the lowest point of deformation of the chest. An index value of less than 2 indicates the absence of deformation, a Holler index above 3.2 is attributed to a strong degree of deformation.

Disadvantages - radiation exposure, only relative indicators based on linear values are used, and the extent and severity of vertical chest deformation are not determined. To assess spinal deformity, an additional radiographic examination is required.

A known method for assessing chest deformity using the non-contact method of computer optical topography. (Patents RU 2154985, А61В 5/107 2000 and RU 2186524, А61В 5/107 2002) The degree of funnel-shaped deformation of the chest is determined by two parameters: the sternum-rib angle and the depth of the deformation arc.

The disadvantage is that only the anterior surface of the chest is evaluated by two parameters, the sterno-vertebral space and the spine are not evaluated, which does not give a complete picture of the deformation of the chest.

Closest to the claimed is a method for determining congenital chest deformities using thoracometry (patent RU 2175522 АВВ 5/107, АВВ 5/00 Shamik VB; Osipochev S.N .; Chepurnoy G.I.). The contours of the anterior chest wall are determined using a thoracometric device consisting of two supporting bars with handles and 50 freely moving graduated measuring rods 11 cm long. Measurements are made segmentwise, starting with the pair of ribs and ending with VIII. After measuring each segment, the scale indicators of each rod are taken and a graphical image of the measured segment is built. The number of measured segments depends on the extent of the measured strain.

Thoracometry allows you to determine the nature of the deformation of the chest and display its contours in the transverse (horizontal) plane at various levels. Thoracometry data provide information on the depth, width of the chest, its oblique dimensions, the ratio of longitudinal and transverse diameters (thoracic index), and the degree of deformation. However, thoracometry does not allow to obtain three-dimensional characteristics of the deformation and to evaluate the shape and orientation of the spine in space, which is necessary when evaluating the combined deformation. In this case, only linear and relative values are determined, which change as the patient grows and therefore cannot be comparable both in dynamics and among the group of patients.

The objective of the invention is to develop a method for evaluating the funnel-shaped deformation of the chest by determining the three-dimensional coordinates of the set of identification points on the surface of the human body for a comprehensive three-dimensional assessment of deformation of the chest and spine.

The problem is solved due to the fact that the jugular notch, the upper and lower edges of the funnel, the bottom of the funnel, the xiphoid process, the left and right edges of the funnel, the points along the right and left mid-axillary lines at the level of the funnel bottom point, are marked with marks on the body surface. along the line of the spinous processes at the level of the points of the upper edge of the funnel and the bottom of the funnel, the spinous processes of the C ₇ , Th ₁₂ and L ₅ vertebrae, the right and left hind spine of the pelvis; determine and record using the three-dimensional scanner three-dimensional coordinates of these points; linear, angular and volumetric parameters, and relative values characterizing the deformation of the chest, spine and their relationship in space are calculated from the obtained coordinates.

The solution of this problem provides a quantitative assessment of the severity of deformity of the chest and spine with the formation of a volumetric diagram characterizing their condition and relationship in space. Such an assessment makes it possible to calculate the values for formulating a detailed diagnosis in accordance with modern classifications, choose the tactics of patient management, monitor age-related changes in deformity of the chest and spine, and, if necessary, choose the optimal tactics of surgical treatment and objectively evaluate its results.

The technical result is achieved by determining the three-dimensional coordinates of the set of points that allow you to calculate the entire set of linear, angular and volumetric parameters, as well as relative values that fully characterize the spatial deformation of the chest and spine. The resulting linear and angular values are not distorted projection and can be represented in a perspective view.

The method is as follows:

The patient takes a standing pose. Identification points are marked on the patient’s body with a felt-tip pen, which allows to fully characterize the deformation:

1. Jugular notch

2. The upper edge of the funnel

3. The bottom of the funnel (the deepest point of the funnel)

4. The bottom edge of the funnel

5. The xiphoid process

6. The left edge of the funnel

7. The right edge of the funnel

8. Points along the right and left mid-axillary lines at the level of the funnel bottom point.

9. A point along the line of the spinous processes at the level of the point of the upper edge of the funnel

10. A point along the line of the spinous processes at the level of the bottom of the funnel.

11. The spinous process of the _7th vertebra

12. Spinous process of Th ₁₂ vertebra

13. The spinous process of the L ₅ vertebra

14. The right rear spine of the pelvis

15. Left rear spine of the pelvis

Using the probe of a three-dimensional scanner, the three-dimensional coordinates of each of these points and the coordinates of the spinous processes of the thoracic and lumbar spine are determined and recorded, by drawing the probe along the line of the spinous processes. The obtained coordinates are stored in the computer database and are used to calculate the following parameters:

1. The length of the funnel (d ₁ ) is the distance between the points of the upper and lower edges of the funnel.

2. The width of the funnel (d ₂ ) is the distance between the points of the left and right edges of the funnel

3. The depth of the funnel (h) is the distance between the bottom point of the funnel and the funnel width line.

4. Chest width (s) - the distance between the points on the right and left mid-axillary lines.

5. The sagittal angle of the depth of the funnel (α ₁ ) is the angle formed by two lines drawn through the points: the upper edge of the funnel and the bottom of the funnel, the bottom of the funnel and the lower edge of the funnel.

6. The horizontal angle of the funnel (α ₂ ) is the angle formed by two lines drawn through the points: the right edge of the funnel and the bottom of the funnel, the bottom of the funnel and the left edge of the funnel.

7. The angle of inclination of the upper wall of the funnel (β ₁ ) is the angle formed by two lines drawn through the points: the upper edge of the funnel and the bottom of the funnel, the upper and lower edges of the funnel.

8. The angle of inclination of the bottom wall of the funnel (β ₂ ) is the angle formed by two lines drawn through the points: the lower edge of the funnel and the bottom of the funnel, the upper and lower edges of the funnel.

9. The angle of inclination of the left wall of the funnel (β ₃ ) is the angle formed by two lines drawn through the points: the left edge of the funnel and the bottom of the funnel, the left and right edges of the funnel.

10. The angle of inclination of the right wall of the funnel (β ₄ ) is the angle formed by two lines drawn through the points: the right edge of the funnel and the bottom of the funnel, the left and right edges of the funnel.

11. The upper size of the retrosternal space: the distance from the point of the upper edge of the funnel to the corresponding level point on the line of the spinous processes (c).

12. The lower size of the retrosternal space: the distance from the point of the bottom of the funnel to the corresponding level point on the line of the spinous processes (d)

13. The inclination of the chord of the thoracic and lumbar spine to the vertical (γ ₁ and γ ₂ )

14. The inclination of the axis of the trunk in the sagittal plane (λ ₁ ) is the angle of deviation from the vertical line connecting the points of the spinous processes of C7 and L5 vertebrae.

15. The inclination of the axis of the trunk in the frontal plane (λ ₂ ) is the angle of deviation from the vertical line connecting the points of the spinous processes of C7 and L5 vertebrae.

16. Deflections of the chords of the thoracic (b ₁ ) and lumbar (b ₂ ) spine - the distance between the middle of the chord and the apex of the arch of the thoracic and lumbar, respectively.

17. The lengths of the chords of the thoracic (h ₁ ) and lumbar (h ₂ ) spine are the length of the segment connecting the points of the spinous processes of C7 and Th12 vertebrae and the points of the spinous processes of Th12 and L5 vertebrae, respectively.

18. The turn of the funnel in the frontal plane is the angle of deviation from the vertical of the line connecting the point of the jugular notch with the point of the xiphoid process.

19. The slope of the sternum in the sagittal plane is the angle of deviation from the vertical of the line connecting the jugular notch to the point of the xiphoid process.

20. The distance of the sternum-side to the left is the distance from the bottom of the funnel to the left mid-axillary line.

21. The distance of the sternum-side to the right is the distance from the bottom of the funnel to the right mid-axillary line.

The length of any segment can be calculated by the formula:

$$L=\sqrt{{\left(Xa-Xb\right)}^2+{\left(Ya-Yb\right)}^2}$$

Where:

L is the length of the segment;

Xa and Ya are the coordinates of one point;

Xb and Yb are the coordinates of the second point.

The angle formed by two lines is calculated by the formula:

Ω = arg (Xa-Xb; Ya-Yb) -90 °

Where:

Ω is the value of the angle;

Xa and Ya are the coordinates of one point;

Xb and Yb are the coordinates of the second point.

Using the obtained parameters are calculated as relative indicators:

- thoracic index according to the formula: d ₁ / d ₂ ,

- Gizycka’s indicator by the formula: d / in,

- Holler index according to the formula - s / d,

and absolute values:

- the volume of the funnel chest deformity - according to the formula: V = d ₁ · d ₂ · h / 6),

- the central angle of the arch of the thoracic (ω ₁ ) and lumbar (ω ₂ ) spine according to the formulas: ω = L · 180 / π · R;

L = √ (h ² + b ² ), R = (h ² + 4b ² ) / 8b;

Where:

ω is the value of the central angle

L - arc length of the thoracic or lumbar spine

R is the radius of the arc of the thoracic or lumbar spine

h - the length of the chord of the arc of the thoracic or lumbar spine

b - deflection of the arch of the thoracic or lumbar spine

The research protocol is presented in the form of real linear and angular quantities and diagrams of the indicated values in projection onto each of the three planes.

The angle of inclination of the walls of the deformation of less than 10 ° allows you to determine the plane-funnel deformation. In other cases, the form of deformation is defined as typical.

The difference in the angles of inclination of the left and right funnel walls of more than 10 ° indicates an asymmetric form of deformation.

The difference in the parameters "distance sternum-side" on the left and right is more than 20 mm. allows you to determine the eccentric type of funnel chest deformity.

The parameter "funnel turn in the frontal plane" of more than 10 ° allows you to identify an unbalanced form of chest deformation.

The presence of changes in the shape and orientation of the spine allows you to determine the combined form of deformation.

The depth of the funnel within 2 cm - 1 degree; 2-4 cm. - 2 degree; more than 4 cm. - 3 degree.

The Gizycko index of more than 0.7 corresponds to I degree, from 0.7 to 0.5 - II degree, less than 0.5 - III degree of deformation.

Holler index above 3.2 is classified as a strong degree of deformation.

The value of the central angle of the thoracic arch in the sagittal plane of more than 40 ° is regarded as kyphotic deformation.

The value of the central angle of the thoracic arch in the frontal plane of more than 0 ° is regarded as scoliotic deformation.

An example of clinical use.

Patient I. 12 years old, and. b. 1236, turned to an outpatient appointment with complaints of deformity of the anterior chest wall detected at birth. The study was conducted using the hardware-software complex "3D orthopedic scanner."

The research protocol is presented in the drawings.

Figure 1 - Layout of all points in the frontal plane

Figure 2 - Arrangement of all points in the sagittal plane

Figure 3 - Arrangement of all points in the horizontal plane

The following identification points were marked on the patient's body: jugular notch (JV), upper edge of the funnel (VK), bottom of the funnel (DW), lower edge of the funnel (PC), xiphoid process (MO), left edge of the funnel (LC), right edge funnels (PC), points along the right (PB) and left (LB) mid-axillary lines at the level of the funnel bottom point, point along the line of the spinous processes at the level of the point of the upper edge of the funnel (ECP), a point along the line of the spinous processes at the level of the bottom point funnels (NTP), spinous process of C ₇ vertebra (C7), spinous process of Th ₁₂ vertebra (Th12), spinous process vertebral current L5 (L5), right posterior pelvic spine (PZO), left posterior pelvic spine (LZO).

The probe of the hardware-software complex "3D Orthopedic Scanner" determined and recorded the coordinates of the above points, and then calculated all the parameters necessary for making a detailed diagnosis.

Parameter Value 01 Funnel length 154 mm 02 Funnel Width 229 mm 03 Depth of the funnel in the sagittal plane 38 mm 04 Depth of funnel in horizontal plane 39 mm 05 The angle of inclination of the upper wall of the funnel 66 ° 06 The angle of the funnel bottom wall 50 ° 07 The angle of the right wall of the funnel 49 ° 08 The angle of inclination of the left wall of the funnel 20 ° 09 Sagittal depth angle of the funnel 99 ° 10 Horizontal funnel depth angle 113 ° 11 Upper retrosternal size 297 mm 12 Lower retrosternal size 250 mm 13 Chest Width 421 mm 14 Central angle of the thoracic region (frontal) 30 ° 15 Central angle of the lumbar (frontal) 35 ° 16 The angle of inclination of the chord of the thoracic (sagittal) 6 ° 17 The angle of inclination of the chord of the lumbar (sagittal) 11 ° 18 Torso in the sagittal plane 7 ° 19 Position of the pelvis (frontal) 3 ° 20 Distance sternum-side left 240 mm 21 distance sternum-side right 183 mm 22 Tilt of the sternum 0 ° 23 Turning the funnel in the frontal plane 4 °

Diagnosis: Typical, asymmetric, eccentric, balanced, combined funnel chest deformity of the II degree; kyphoscoliotic deformity of the spine.

The patient is referred to a specialized hospital for surgical treatment.

Claims (1)

A method for evaluating the funnel-shaped deformation of the chest by determining the position of the set of points on the surface of the trunk, characterized in that the jugular notch, the upper and lower edges of the funnel, the bottom of the funnel, the xiphoid process, the left and right edges of the funnel, marks the points on the right and left mid-axillary lines at the level of the funnel bottom point, points along the line of the spinous processes at the level of points of the upper edge of the funnel and funnel bottom, spinous processes of C ₇ , Th ₁₂ and L ₅ vertebrae, right and left hind pelvic spines; determine and record using the three-dimensional scanner three-dimensional coordinates of the marked points; linear, angular and volumetric parameters, relative values characterizing the deformation of the chest and spine, their relationship in space are calculated according to the obtained coordinates.

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