A classification method and device for developmental dysplasia of the hip based on X-ray films

Abstract

This application relates to the field of medical diagnostic technologies, and particularly to a method and device for classifying developmental dysplasia of the hip based on X-ray films. The method includes the following steps: (1) Establishing the standard position of the X-ray film; (2) Measuring the X-ray film to determine reference points; (3) Determining measurement parameters based on the reference points; (4) Classifying according to the measurement parameters. The new classification method of the present invention covers a wider range of diseases, has a stronger ability to distinguish deformities, more reliable observation of stability, and stronger guiding significance for surgery: 1. It can accurately identify different types of special hip dysplasia, etc., and classify according to the surgical difficulty to select appropriate prostheses and preoperative preparations. 2. It is easier to calculate, and the identification of the false acetabulum is relatively simple. 3. It can accurately predict the severity of proximal femoral deformities, guide the position of acetabular construction, and evaluate whether patients with high-level hip dysplasia require special prostheses and subtrochanteric osteotomy.

Description

Technical Field

[0001] This application relates to the field of medical diagnosis technologies, and particularly relates to a classification method and device for developmental dysplasia of the hip based on X-ray films. Background Art

[0002] Developmental dysplasia of the hip joint (DDH) refers to the abnormal morphology or position of the femoral head and acetabulum in a child at birth or during the growth and development process. In 1989, "dysplasia of the hip joint" was renamed from congenital to developmental to indicate that this disease is not just a birth defect. To improve the understanding of this disease, attempts have been made to classify developmental dysplasia of the hip joint in order to provide better guidance for surgical treatment. The Crowe classification proposed in 1979 is as follows: on a standard anteroposterior hip radiograph, the Crowe classification defines the vertical distance from the junction of the head and neck to the horizontal line of the ipsilateral teardrop as the dislocation height of the femoral head on that side, and the vertical distance from the horizontal line passing through the highest point of the ipsilateral ilium to the horizontal line passing through the lowest point of the ipsilateral ischium as the pelvic height. The femoral head displacement height / pelvic height < 10% is Crowe type I, 10% - < 15% is Crowe type II, 15% - < 20% is Crowe type III, and > 20% is Crowe type IV. The Crowe classification is the most commonly used classification method in clinical practice. However, given that the disease definition and disease spectrum have changed, the Crowe classification proposed in 1979 is no longer applicable.

[0003] The Crowe classification only classifies developmental dysplasia of the hip joint from the dislocation height. In total hip arthroplasty, the dislocation height is one of the important guiding factors for the surgery. However, from the perspective of postoperative recovery, it is far from enough to only refer to the dislocation height for surgical design. When the human body walks upright, the femur will be stimulated by forces, and mechanical stimulation has an important impact on the morphological development of the femur and the reconstruction of the skeletal load-bearing structure. In some patients with Crowe type III and IV, after the femoral head is dislocated, it forms a false acetabulum by squeezing with the ilium, causing the femur to be re-loaded and the development of the femur to tend to be normal; at the same time, there are also some patients who do not form a false acetabulum, and the femur is less loaded, and in these patients, the degree of femoral deformity is higher and the surgical requirements are also higher. In addition, the gluteus medius is an important structure for hip abduction, and its insertion point is the greater trochanter of the femur. In some patients, abnormal development of the femoral neck leads to a too small neck-shaft angle and relative upward displacement of the greater trochanter. From the perspective of the Crowe classification alone, such patients are often Crowe type I, and only need to adopt the same surgical plan as patients with normal femoral development. However, during the operation, the gluteus medius is often too short, resulting in difficulty in reducing the prosthesis after replacement, and forced reduction may even cause traction damage to muscles, blood vessels, and nerves. Obviously, the Crowe classification fails to provide good theoretical guidance for hip replacement.

[0004] The Crowe classification also has some inherent defects. For example: 1. The anatomical landmarks at the femoral head-neck junction vary greatly, and the correlation with the hip joint rotation center is poor; 2. The femoral head-neck junction has little mechanical significance; 3. In about 20% of patients, the femoral head-neck junction is difficult to identify; 4. Only the dislocation height is considered, without considering the influence of the proximal stress of the false acetabulum on the development of the proximal femur.

[0005] Therefore, there is an urgent need for a classification method and device for developmental dysplasia of the hip based on X-ray films. Summary of the Invention

[0006] The present invention first provides a classification method for developmental dysplasia of the hip based on X-ray films, and the method includes the following steps:

[0007] (1) Establish the standard position of the X-ray film;

[0008] (2) Measure the X-ray film to determine the reference points;

[0009] (3) Determine the measurement parameters according to the reference points;

[0010] (4) Classify according to the measurement parameters;

[0011] The above method is used for non-diagnostic or non-therapeutic purposes.

[0012] In some embodiments, the X-ray films are all taken in the standard anteroposterior pelvic position.

[0013] In some embodiments, the standard image of the X-ray film shows:

[0014] (1) The image includes all pelvic bones and the proximal 1 / 4 of the femur, and is symmetrical left and right, with the pelvic cavity shown in the center of the image;

[0015] (2) The pubis does not overlap with the sacral vertebrae, and the inner edges of the two greater trochanters overlap with the femoral neck by 1 / 2;

[0016] (3) The iliac wings on both sides and the textures of other bones are clearly visible.

[0017] In some embodiments, the reference points include marking the highest point of the femoral greater trochanter as point A, defining the highest end of the ipsilateral pelvis as point B, and defining the lowest point of the ipsilateral pelvis ischium as point C.

[0018] In some embodiments, the criteria for classification are defined as follows: Type I is defined as the value of F / D < 100%; Type II is defined as 100 - 125%; Type III is defined as 125% - 150%; Type IV is defined as the ratio > 150%; if the developmental dysplasia of the hip is bilateral, then change from the femoral head height to the pelvic height; Types I - IV are respectively defined as F / L < 20%, 20 - 25%, 25 - 30%, > 30%.

[0019] The present invention also provides an application of the above method, and the application is a) preparing a drug for developmental dysplasia of the hip; or b) screening a drug for developmental dysplasia of the hip; or c) diagnosing or treating developmental dysplasia of the hip;

[0020] Optionally, the method is used for non-diagnostic purposes or non-therapeutic purposes.

[0021] The present invention also provides a classification device for developmental dysplasia of the hip based on X-ray films, and the classification device includes a functional module for implementing the above method.

[0022] In some embodiments, the functional module includes a determination module and a three-dimensional body position detection device.

[0023] In some embodiments, the determination module includes a first determination module, a second determination module, a third determination module, and a fourth determination module.

[0024] In some embodiments, the first determination module takes a real-time picture of the subject's body position; the second determination module is used to obtain X-ray film data; the third determination module is used to determine a reference point; and the fourth determination module determines measurement parameters according to the reference point.

[0025] The present invention finally provides an application of the above classification device, and the application is a) preparing a drug for developmental dysplasia of the hip; or b) screening a drug for developmental dysplasia of the hip; or c) diagnosing or treating developmental dysplasia of the hip;

[0026] Optionally, the method is used for non-diagnostic purposes or non-therapeutic purposes.

[0027] Compared with the prior art, the present invention has at least the following beneficial effects:

[0028] Compared with the Kerckhoffs classification, the new classification method of the present invention has stronger ability to distinguish deformities, more reliable observation of stability, and stronger guiding significance for surgery: 1. It can accurately identify different types of special developmental dysplasia of the hip, slipped capital femoral epiphysis, sequelae of Perthes disease, coxa vara, epiphyseal dysplasia, etc., classify according to the surgical difficulty, and select appropriate prostheses and preoperative preparations. 2. The measurement method of the new classification is similar to the Crowe classification, easier to calculate, and the identification of the false acetabulum is relatively simple. 3. Based on the two-dimensional classification system, it can accurately predict the severity of the proximal femoral deformity, guide the position of acetabular construction, and evaluate whether high-level developmental dysplasia of the hip patients need special prostheses and subtrochanteric osteotomy. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 . Original X-ray film;

[0030] Figure 2 .Determine the reference point diagram;

[0031] Figure 3 . Schematic diagram of calculation of the method of the present invention. DETAILED DESCRIPTION

[0032] In order to make the technical problems, technical solutions and advantages to be solved by the present invention more clear, a detailed description will be given below with reference to the accompanying drawings and specific embodiments.

[0033] Example 1 A method for classifying developmental dysplasia of the hip based on X-rays

[0034] The method comprises:

[0035] 1. Establish standard X-ray positions:

[0036] When taking X-rays, the subjects were all photographed in the standard anteroposterior pelvic position (see Figure 1 ).

[0037] (1) The subject lies supine on the photography table, with the midsagittal plane of the body perpendicular to the table and coinciding with the midline of the table;

[0038] (2) Both lower limbs are straightened, both feet are slightly internally rotated (10° to 15°), both toes are close together, and the distance from the anterior superior iliac spine to the table surface is equal on both sides;

[0039] (3) The upper edge of the irradiation field and the detector includes the iliac crest, and the lower edge reaches 3.0 cm below the pubic symphysis;

[0040] (4) The source-image distance is 100.0 cm;

[0041] (5) The center line is aligned 3.0 cm below the midpoint of the line connecting the two anterior superior iliac spines and shot vertically into the center of the detector.

[0042] Standard image display:

[0043] (1) The image includes all pelvic bones and the proximal 1 / 4 of the femur, and is bilaterally symmetrical, with the pelvic cavity located in the center of the image;

[0044] (2) The pubic bone does not overlap with the sacrum, and the inner edge of the greater trochanter on both sides overlaps with the femoral neck by 1 / 2;

[0045] (3) The iliac wings and other bone textures on both sides are clearly visible.

[0046] 2Measure the X-ray film to be measured and determine the reference point:

[0047] Mark the highest point of the greater trochanter of the femur as point A, define the lowest point of the ipsilateral pelvis as point B, define the highest point of the ischium of the ipsilateral pelvis as point C, define the horizontal line passing through point B as line B, and define the horizontal line passing through point C as line C. (See Figure 2 ) Define the distance between line B and line C as L.

[0048] Randomly select 10 points on the contour of the femoral head on the X-ray film, mark them as points N1 to N10, require the distance between two points to be greater than 1 / 20 of the length of the femoral head contour, and use a circle to fit the contour of the femoral head to make the sum of the distances from the 10 selected points to the circumference of the circle the shortest. (See Figure 3 ) Define the diameter of the circle as the femoral head diameter D.

[0049] Randomly select 10 points on the contour of the true acetabulum on the X-ray film, mark them as points M1 to M10, require the distance between two points to be greater than 1 / 20 of the length of the true acetabulum contour, and use a circle to fit the contour of the true acetabulum to make the sum of the distances from the 10 selected points to the circumference of the circle the shortest. Mark the center of the circle as point E, and measure the vertical distance from point E to point A, mark it as distance F.

[0050] Define type I as the value of F / D: <100%; type II as 100 - 125%; type III as 125% - 150%; type IV as the ratio: >150%. If the hip dysplasia is bilateral, then change from the femoral head height to the pelvis height. Types I - IV are respectively defined as F / L < 20%, 20 - 25%, 25 - 30%, > 30%.

[0051] Example 2 A classification measurement device for developmental hip dysplasia based on X-ray films

[0052] The device includes: a first determination module, a three-dimensional body position detection device, which can capture the body position of the subject in real time, and determine the X-ray film range according to the body position of the subject; and put forward adjustment requirements according to the body position. A second determination module for obtaining X data processing. A third determination module for determining reference points, the reference points including: the highest point A of the greater trochanter of the femur, the lowest point B of the ipsilateral pelvis, the highest point C of the ischium of the ipsilateral pelvis, randomly selecting points N1 to N10 on the contour of the femoral head on the X-ray film, and randomly selecting points M1 to M10 on the contour of the true acetabulum on the X-ray film. A fourth determination module for determining measurement parameters according to the reference points, the measurement parameters including: defining the horizontal line passing through point B as line B, and defining the horizontal line passing through point C as line C. Define the distance between line B and line C as L. Use a circle to fit the contour of the femoral head to make the sum of the distances from N1 to N10 to the circumference of the circle the shortest. Define the diameter of the circle as the femoral head diameter D. Use a circle to fit the contour of the true acetabulum to make the sum of the distances from points M1 to M10 to the circumference of the circle the shortest. Mark the center of the circle as point E, measure the vertical distance from point E to point A, mark it as distance F. Calculate the values of F / D and F / L.

[0053] The first determination module uses the three-dimensional body position detection device in the following way to capture the subject's body position in real time; and proposes adjustment requirements based on the body position: (1) The subject lies on his back on the photography table, with the midsagittal plane of the human body perpendicular to the table surface and coincident with the midline of the table surface; (2) The lower limbs are straight, the feet are slightly internally rotated (10° to 15°), the toes are close together, and the distance from the anterior superior iliac spines to the table surface is equal on both sides; (3) The upper edge of the irradiation field and the detector includes the iliac crest, and the lower edge reaches 3.0 cm below the pubic symphysis; (4) The source-image distance is 100.0 cm; (5) The center line is aligned with 3.0 cm below the midpoint of the line connecting the two anterior superior iliac spines and vertically enters the center of the detector.

[0054] After the subject is positioned normally, move the imaging part so that (1) the image includes all pelvic bones and the proximal 1 / 4 of the femur, and is symmetrical on both sides, with the pelvic cavity located in the center of the image; (2) the pubic bone does not overlap with the sacrum, and the inner edge of the greater trochanter on both sides overlaps with the femoral neck by 1 / 2; (3) the iliac wings on both sides and the texture of other bones are clearly visible.

[0055] The second determination module is used to obtain X-ray data in the following manner, by using the X-ray film: using threshold segmentation and region growing method to determine the femur and pelvis contours.

[0056] The third determination module is used to determine the reference point, marking the highest point of the greater trochanter of the femur as point A, defining the highest end of the ipsilateral pelvis as point B, and defining the lowest point of the ipsilateral pelvic ischium as point C.

[0057] Ten points were randomly selected on the femoral head contour of the X-ray film and marked as points N1 to N10, and the distance between any two points was required to be greater than 1 / 20 of the length of the femoral head contour.

[0058] Ten points were randomly selected on the true acetabulum contour of the X-ray film and marked as points M1 to M10, and the distance between any two points was required to be greater than 1 / 20 of the true acetabulum contour length.

[0059] The fourth determination module is used to determine measurement parameters according to the reference point, wherein the measurement parameters include: defining a horizontal line passing through point B as line B, defining a horizontal line passing through point C as line C, and defining a distance between line B and line C as L.

[0060] A circle is used to fit the femoral head contour so that the sum of the distances from the 10 points selected from points N1 to N10 to the circumference of the circle is the shortest. The diameter of the circle is defined as the femoral head diameter D.

[0061] Make the sum of the distances from the 10 points selected from point M1 to M10 to the circumference of the circle the shortest. Mark the center of the circle as point E, measure the vertical distance from point E to point A, and mark it as distance F.

[0062] Define type I as the value of F / D: < 100%; type II as 100 - 125%; type III as 125% - 150%; type IV as the ratio: > 150%. If the hip dysplasia is bilateral, change from the femoral head height to the pelvic height. Types I - IV are respectively defined as F / L < 20%, 20 - 25%, 25 - 30%, > 30%.

[0063] Example 3 Construction of a classification measurement device for developmental hip dysplasia based on X-ray films

[0064] The first image acquisition module can automatically take photos of the patient's position; the second confirmation module can automatically identify the bony landmarks on the patient's body surface. The image acquisition module selects 500 photos of the patient's position, and the senior doctor marks the bony landmarks of the patient and provides them to the system for training. The senior imaging doctor sets the relative positions where the bony landmarks of the patient should be in the standard position and supplies them to the system to issue correction instructions. Repeat the above steps until the patient's position is judged by the senior imaging doctor. When the accuracy rate of 100 cases reaches more than 99%, the training can be stopped. The third application module integrates the trained intelligent program with the X-ray imaging system and automatically takes X-ray films when the position meets the requirements.

[0065] Example 4 Differences between the surgical planning and actual surgical statistics of the classification of developmental hip dysplasia based on X-ray films

[0066] Randomly select a total of 134 DDH patients who underwent surgeries performed by the same senior doctor from January 1, 2023 to January 1, 2024. Statistically analyze the classification of the DDH on the operative side of the patients according to the classification method of the present invention and the Crowe classification method. If the classification results according to the classification method of the present invention and the Crowe classification are the same, group them according to the classification, and label types I, II, III, and IV as groups AⅠ, AⅡ, AⅢ, and AⅣ respectively; if the classification results according to the classification method of the present invention and the Crowe classification are different, label types I, II, III, and IV divided according to the method of this study as groups BⅠ, BⅡ, BⅢ, and BⅣ respectively; label types I, II, III, and IV divided according to the Crowe classification method as groups CⅠ, CⅡ, CⅢ, and CⅣ respectively. Statistically analyze the operation time, blood loss, presence or absence of intraoperative fractures, differences between the expected and actual prosthesis models, whether special prostheses and subtrochanteric osteotomy are required in each group.

[0067] The data was subjected to normality test. The results of the operation time and blood loss in each group conform to the normal distribution (P < 0.05). The presence or absence of intraoperative fractures and the differences between the expected and actual prosthesis models in each group do not conform to the normal distribution (P > 0.05). The t-test was used to statistically analyze whether there are differences between groups AⅠ, BⅠ, and CⅠ in terms of operation time and blood loss, between groups AⅡ, BⅡ, and CⅡ, between groups AⅢ, BⅢ, and CⅢ, and between groups AⅣ, BⅣ, and CⅣ.

[0068] The results showed that there was no statistical difference between groups AⅠ and BⅠ (P > 0.05), between groups AⅡ and BⅡ (P > 0.05), between groups AⅢ and BⅢ (P > 0.05), and between groups AⅣ and BⅣ (P > 0.05).

[0069] The results showed that there were statistical differences between CⅠ and groups AⅠ and BⅠ (P < 0.05), between CⅡ and groups AⅡ and BⅡ (P < 0.05), between CⅢ and groups AⅢ and BⅢ (P < 0.05), and between CⅣ and groups AⅣ and BⅣ (P < 0.05).

[0070] The newly invented classification method has stronger ability to distinguish deformities, more reliable observation stability, and greater guiding significance for surgery: 1. It can accurately identify different types of special hip dysplasia, slipped capital femoral epiphysis, sequelae of Perthes disease, coxa vara, epiphyseal dysplasia, etc., and classify them according to the surgical difficulty to select appropriate prostheses and preoperative preparations. 2. The measurement method of the new classification is similar to the Crowe classification, easier to calculate, and the identification of the false acetabulum is relatively simple. 3. Based on the two-dimensional classification system, it can accurately predict the severity of proximal femoral deformities, guide the position of acetabular construction, and evaluate whether high-level hip dysplasia patients need special prostheses and subtrochanteric osteotomy.

[0071] The above is the preferred embodiment of the present invention. It should be noted that for those of ordinary skill in the art of this technology, without departing from the principle described in the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A classification device for developmental dysplasia of the hip based on X-ray films, characterized in that, The classification device includes functional modules for implementing the following method: The method includes the following steps: (1) Establish the X-ray film shooting position; all X-ray films are taken in the anteroposterior view of the pelvis; the image display standard of the X-ray film is as follows: (1.1) The image includes all pelvic bones and the proximal 1 / 4 of the femur, and is symmetric left and right, with the pelvic cavity shown in the center of the image; (1.2) The pubis does not overlap with the sacral vertebra, and the inner edges of the two greater trochanters overlap with the femoral neck by 1 / 2; (1.3) The iliac wings on both sides and the textures of other bones are clearly visible; (2) Measure the X-ray film to determine the reference points; the reference points include marking the highest point of the greater trochanter of the femur as point A, defining the lowest point of the ipsilateral pelvis as point B, and defining the highest point of the ipsilateral pelvis ischium as point C; defining the horizontal line passing through point B as line B, defining the horizontal line passing through point C as line C, and defining the distance between line B and line C as L; (3) Determine the measurement parameters according to the reference points; randomly select 10 points on the femoral head contour of the X-ray film, marked as points N1 to N10, requiring the distance between two points to be greater than 1 / 20 of the femoral head contour length, and use a circle to fit the femoral head contour to make the sum of the distances from the selected 10 points to the circumference of the circle the shortest; define the diameter of the circle as the femoral head diameter D; Randomly select 10 points on the true acetabulum contour of the X-ray film, marked as points M1 to M10, requiring the distance between two points to be greater than 1 / 20 of the true acetabulum contour length, and use a circle to fit the true acetabulum contour to make the sum of the distances from the selected 10 points on the true acetabulum contour to the circumference of the circle where the true acetabulum contour is located the shortest; mark the center of the circle where the true acetabulum contour is located as point E, measure the vertical distance from point E to point A, marked as distance F; calculate the values of F / D and F / L; (4) Classify according to the measurement parameters; the classification criteria for developmental dysplasia of the hip are as follows: If the hip dysplasia is unilateral, define type I as the value of F / D: <100%; define type II as the value of F / D: 100 - 125%; define type III as the value of F / D: 125% - 150%; define type IV as the value of F / D: >150%; If the hip dysplasia is bilateral, define type I as the value of F / L: <20%; define type II as the value of F / L: 20 - 25%; define type III as the value of F / L: 25 - 30%; define type IV as the value of F / L: >30%.

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