RU2533837C1 - Method for ultrasonic evaluation of lateral patellar dislocation - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: contour of an upper surface of the patellar is visualised. An ultrasonic section is imaged by a scanner sensor mounted on the patellar mid-line drawn from an apex to a base at 1-1.5 cm above the apex edge in the proximal direction, and inclined in the countercranial direction to a frontal plane specified within 40 to 45°, provided the contour of an anterior surface of the patellar is visualised on the section with an acoustic shadow found within the anterior contours of the medial and lateral epicondyles of the femur. If the acoustic shadow dislocates laterally on this section in relation to the contours of the epicondyles so that at least the partial contour of the intercondyloid fossa including its lower level on the section image is visualised, a vertical line is drawn through a lower point of this contour. Another vertical line is drawn through the middle of a segment connecting the lateral and medial points of the patellar contour the outermost from the patellar mid-line. The lateral patellar dislocation is evaluated by measuring the distance between the above lines.

EFFECT: providing the non-invasive, rapid, accessible and accurate determination of the lateral patellar dislocation by the optimal technique for the ultrasonic examination.

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Description

The invention relates to medicine, namely to orthopedics and traumatology, and can be used to assess the lateral dislocation of the patella at an early stage of the diagnostic process.

Damage to the knee joint is a serious problem in clinical medicine, as it is a fairly common cause of disability and disability.

Pathology of the patellofemoral joint (PPS) is a common, but insufficiently studied problem. According to some authors, approximately 15% of first-time patients have an isolated patellofemoral pathology. In another 25% of patients, patellofemoral symptoms are a secondary manifestation of other diseases, such as instability of the anterior cruciate ligament and meniscus tears. The lateral dislocation of the patella and its manifestation as a syndrome of lateral hyperpression of the patella (SLHN) is a fairly common pathology of the patellofemoral joint (PPS), which occurs mainly among children and adolescents. SLNG, according to different authors, is the cause of 7 to 15% of all complaints about orthopedic pathology of the knee joint.

Syndrome of lateral hyperpression of the patella is more or less pronounced constant aching pain in the anterior part of the knee joint (aggravated by flexion), due to secondary chondromalacia, as well as irritation of nerve fibers located directly in the lateral patella support. Swelling of the joint, recurrent synovitis, crunch during movements are noted. With the progression of hyperpression, a feeling of instability, looseness in the joint, pain pseudo-blocking of the joint may occur. In most cases, the causes of the development of lateral syndrome of patellar lateral hyperpression are abnormalities in the development of the knee joint: congenital deformities of the patella, lateral condyle of the femur hypoplasia, high patella - patellaalta, laterally located tibial tuberosity, increased density of the lateral patellar retainer and other ankles. It is also possible to develop this syndrome after traumatic injuries of a normally formed joint, resulting in fibrosclerotic changes in damaged muscles and ligaments, stretching of the medial patella retainer, stretching of the joint capsule, which is not compensated during the healing process and leads to a shift of the patella outward. Moreover, as a result of overloading of the lateral sections of the PPS, the level of tension in the bone-cartilage and soft tissue elements of the joint increases, which leads to the development of chondromalacia, asymmetric wear of the joint with the development of degenerative-dystrophic changes in the bone-cartilage structures. For the prevention of complications in patients with lateral hyperpression syndrome of the patella, it is necessary to pay special attention to a thorough examination of patients with the aim of early detection of signs of this pathology in them. However, in the initial stage of lateral dislocation of the patella, these symptoms may be mild. At the same time, the detection of this disease at an early stage is important, since treatment at an early stage of the manifestation of the disease gives the best results.

For diagnosis, use such methods of research of the knee joint as:

- radiographs of the knee joint, which assess its condition;

- computed tomography and magnetic resonance imaging. These are modern, highly informative, but expensive research methods, with one of which radiation exposure to the patient is inevitable. Best suited for determining soft tissue damage: ligamentous apparatus, damage to the menisci, cartilage, etc. Thus, there is a known method for determining lateralization of the patellar ligament (patent RU No. 2271148, IPC A61B 6/03). The method includes determining the angle of displacement of the patella, and the angle of displacement of the patella and its own ligament relative to the bed of the patella is determined; for this, computed tomography of the knee joint is performed, scan levels are established from the tomogram: proximal - up from the patella to 1.5 cm, distally - at tuberosity of the tibia, after which a tomogram is applied at the level of the central parts of the patella bed and a tomogram at the level of attachment of the patellar ligament, then on In the created image, the angle formed by two lines is measured: a straight line drawn through the center of the patella bed and the center of the femur, and a straight line drawn through the center of the tibia and the site of attachment of the patellar ligament.

- Ultrasound has a number of advantages over x-ray techniques. This is primarily the lack of ionizing radiation, accessibility. In addition, this study is much cheaper. However, in the pathology of the patellofemoral zone, ultrasound is used mainly for acute injuries of the patella, while the pathology of the patella retainer and adjacent tissues are examined.

Known methods of ultrasound examination of knee tissue, such as “A method for predicting cartilage damage on the articular surface of the patella in patients with femoral-patellar pathology of the knee joint by measuring the angle of the patella, characterized in that they conduct screening ultrasound examination of the knee joint, measure the angle of the relationship between the plane of the upper the poles of the patella and the plane of the anterior nonarticulating surface of the patella and with its values greater than 120 °, are predicted by Cartilage reduction on the articular surface of the patella ”(patent RU No. 2400146, IPC A61B 8/08) or“ Method for ultrasound diagnosis of injuries of the meniscus of the knee joints by polypositional examination of the joint with the straightened and bent tibia, characterized in that the ultrasound scanner sensor with an operating frequency of 5- 10 MHz is set perpendicular to the joint gap of the knee joint from the lateral or medial surface of the joint with the bent tibia at an angle of 90 °, and then the lower leg is traced anteriorly perpendicular to its axis and along the presence of a break in the meniscus contour and the tear line is diagnosed with damage to the anterior horn of the lateral or medial meniscus ”(RU patent No. 2282399, IPC A61B 8/00, A61B 8/08).

The publication, "Ultrasound Diagnostics in Traumatology and Orthopedics", N. Eskin, CITO, Moscow, 2009, describes an ultrasound study in which the patellar contours are visualized (smooth, uneven), the integrity of the ligament is established (broken, not broken) , its structure (homogeneous, heterogeneous, decreased echogenicity), thickness, presence of bursitis (yes, no).

All these methods relate to the diagnosis of intraarticular knee elements. The ultrasonic method for determining the lateral dislocation of the patella is unknown. In addition, it is argued that ultrasound can only detect indirect signs of patellar dislocation, such as damage to the medial patella stabilizers in the form of diffuse thickening of soft tissues, uneven increase in echogenicity with loss of clarity of differentiation of structures of the medial joint, thickening of the synovial membrane, and these signs could identify only in the acute period of injury (Timofeev I.V. Abstract of dissertation "Clinic, diagnosis and endoscopic methods of treatment acute dislocation of the patella in children. ”-Moscow - 2004).

Meanwhile, timely detection of the amount of patella displacement in the initial period of the diagnostic process is important for the subsequent determination of the degree of patellar displacement and for the selection of treatment tactics for such displacement (mild and moderate degree, in which conservative treatment is possible, severe degree, in which in most cases surgical treatment).

The invention is aimed at solving the problem of creating a method for determining the lateral dislocation of the patella at an early stage of the diagnostic process in a non-invasive, inexpensive way, eliminating radiation exposure to the patient.

The technical result of the claimed invention is the possibility of non-invasive quick and accurate determination of the lateral dislocation of the patella, the availability and simplification of diagnosis at an early stage of the diagnostic process with sufficient reliability.

This technical result is achieved in that the ultrasound determination of the lateral dislocation of the patella includes visualization of the contour of the upper surface of the patella. Then, an ultrasound image is obtained by a sensor located on the middle, drawn in the direction from the apex to the base of the patella line, 1-1.5 cm proximally above the edge of its apex. In addition, the sensor is transversely inclined in a countercranial direction at an angle to the frontal plane, selected from 40 to 45 ° from the visualization condition on a section of the contour of the anterior surface of the patella with an acoustic shadow located in the region of the anterior contours of the medial and lateral epicondyle of the femur. After that, with lateral displacement of the acoustic shadow relative to the contours of the epicondyles so that at least an incomplete contour of the intercondylar recess, including its lower level, is visualized on the slice, a vertical line is drawn through the lower point of this contour of the recess in the image of the slice. Then, in the image through the middle of the segment connecting the lateral and medial points of the patella contour, the farthest from the vertical line drawn from the apex to the base of the patella midline. The lateral dislocation of the patella is determined by measuring the distance between the drawn lines

The method is as follows.

When the patient is standing on his back from the front access, the contours of the upper surface of the patella are visualized according to the generally accepted standard method, for example, using an Accuvix V-10 ultrasound scanner, a 5.0-13 MHz linear sensor. After that, the sensor is placed on the midline of the patella 1-1.5 cm above the lower point of its apex with an inclination in the countercranial direction at an angle to the frontal plane, selected from 40 to 45 ° from the visualization condition on a slice of the contour of the anterior surface of the patella with acoustic a shadow located in the anterior contours of the medial and lateral epicondyle of the femur (Fig. 1, 2). In the freeze frame mode on the created ultrasound image, including the contour of the anterior surface of the patella 5 with an acoustic shadow, in the region of the anterior contours of the medial and lateral epicondyle of the femur, the location of the acoustic shadow 6 from the patella, which is normally superimposed on the intercondylar recess 4, overlapping it and the lower point A of the recess, as well as the partially lateral and medial epicondyles of the femur (Fig. 1). In the absence of such an overlap, with lateral displacement of the acoustic shadow 6 so that at least an incomplete contour of the intercondylar recess is visualized, including the lower level of the intercondylar recess with the lowest point of the recess, in the image (Fig. 2), 4 the lower point of the recess and mark it as point A, through which a vertical line 1 is drawn. After that, on the resulting image, connect the lateral C and medial D points of the patellar contour 5 with a segment 3, most removed from the midline of the patella. A point is marked In the middle of this segment, through which a vertical line 2 is drawn. As already noted, the normal application of the shadow of the patella 6 to the intercondylar cavity is visualized so that its lower level is overlapped (Fig. 1), with no lateral displacement.

The lateral dislocation of the patella is determined by measuring the distance L (in mm) between the drawn lines 1 and 2. This qualitative characteristic allows, if necessary, to assess the degree of displacement of the patella. The greater the distance L, the greater the degree of displacement of the knee pad.

Studies have shown that with a slight lateral displacement (clinical example 3).

Clinical example 1

Patient R. Age 36 L, complained of pain in the knee joint, constant crunching when squatting and playing sports. An ultrasound examination of the joint was carried out, in which, in addition to partial damage to the internal meniscus, the lateralization of the patella with a displacement in accordance with the claimed method of 1.45 cm was revealed during examination in accordance with the claimed method — the distance is determined using software (Figs. 3, 3a, where shows an ultrasound tomogram of the patient with signs of lateralization of the patella). In Fig. 3, for a more visual illustration, all lines are graphically strengthened, in Fig. 3a - a natural image of a tomogram with construction lines). In fig. 3 shows: point A, marked at the lowest point of the intercondylar recess and vertical line 1, drawn in the image plane in the freeze frame, point B in the middle of the segment connecting the lateral and medial points of the patella contour, farthest from the midline of the patella, and vertical line 2 drawn through this point. The distance between these lines is 1.45 cm.

In order to verify the method, the patient underwent CT of the knee joint. According to a CT study, the lateralization of the patella was confirmed, namely (Fig. 4), the results are as follows:

The joint gap of the knee joint can be traced throughout, slightly narrowed in the lateral region. Joint surfaces are even and clear. The bone structure in the bones of the joint is not changed. Marginal bone sharpening of the intercondylar elevation on the left. The patella is laterally displaced by 1.5 cm.

The angle of congruence of the patello-femoral articulation = 32 gr. (N = 11-16 gr.)

The angle of the patella = 2 gr. (N> 7 gr.)

CONCLUSION: Lateralization of the patella

Recommended surgical treatment at the place of residence.

Clinical example 2. Patient Sh. Born in 1999 was admitted for research and treatment with a diagnosis of post-traumatic arthropathy at the Federal State Budgetary Institution of FTTsOe of Cheboksary with complaints of pain in the left knee joint. A history of sports injury in September 2012 was not performed.

She was consulted by a traumatologist at the Federal State Budgetary Institution of FTsTOE of Cheboksary, she was clinically suspected to have lateralization of the patella, with chronic damage to the medial retainer. 10.23.13 g ultrasound of the left knee joint: no signs of meniscus damage were detected. In accordance with the claimed method, lateralization of the patella with a displacement of 1.1 cm, a violation of the architectonics of the medial retainer (Fig. 5 image of the patient’s tomogram) was revealed.

For verification on 10.23.13 g, an MR study of the knee joint was performed. There were signs of lateralization of the patella on the left (10 mm). Injured damage to the medial patella retainer (Fig. 6).

10/23/13 The operation was performed: Arthroscopic stabilization of the left patella, plastic of the internal retainer. The external and internal parts of the joint capsule were released, the medial retainer was broken, the patella was mobilized, the internal departments with the retainer were sutured with three subcutaneous sutures along Yamamoto through the medial edge of the patella. The patella is set in the correct position, the sutures are tightened in a position of moderate flexion of the knee joint with the formation of duplicature.

Clinical example 3. Patient P., age 44, turned to the diagnostic department with complaints of pain in the right knee joint arising from physical exertion, more on the inner surface.

An ultrasound examination of the knee joint revealed a moderate effusion in the cavity, minor degenerative changes in the menisci, with a zone of damage in the projection of the anterior horn of the inner meniscus. The patella was examined in accordance with the claimed method. In this case, the shadow of the patella is slightly displaced in the lateral direction, but covers the region of the intercondylar recess, including the lower level. It is concluded that the patella is echographically centered.

Fig. 7 shows a sonogram on which the upper patella contour is visualized, behind which an acoustic shadow is determined, which is clearly superimposed on the entire area of the intercondylar recess. In this case, the line from the lower point of the intercondylar recess is drawn with orientation to the anatomical location of the part of the contours of the epicondyle, not covered by a shadow.

Figure 8 shows a CT scan of patient P. Joint joints of the knee joints are traced throughout, not narrowed. Joint surfaces are even and clear. The bone structure in the bones of the joints is not changed.

ON RIGHT:

Caton-Deschamps Index = 1.2 (N = 0.6-1.2)

The angle of congruence of the patello-femoral articulation = 15 g. (N = 11-16 gr.)

The angle of the patella = 28 gr. (N> 7 gr.)

LEFT:

Caton-Deschamps Index = 1.1 (N = 0.6-1.2)

The angle of congruence of the patello-femoral articulation = 16 gr. (N = 11-16 gr.)

The angle of the patella = 29 gr. (N> 7 gr.)

Conclusion: No pathological changes were found.

The claimed method was studied and analyzed 46 patients aged 14 to 44 years. The selection criteria were, first of all, complaints of episodic crunch during flexion and extension of the joint, inconstant pains on the lateral surface of the joint, which the patient cannot clearly characterize, and the history of the episode investigated by the dislocation with spontaneous adjustment of the patella (according to the patient). At the same time, the majority of those examined during initial treatment and clinical interpretation of the condition had a “mask” of damage to the external meniscus. Only 4 patients had a clearly defined clinical diagnosis (habitual dislocation of the patella with verification by radiation methods), but an ultrasound examination, to the extent that the claimed method represents, was not performed. All patients underwent an MRI scan (SIMENS "MAGNETOM Avanto" 1.5 T) or CT scan ("SOMOTOM Emotion 16") study, in order to correlate the declared parameters of the ultrasound technique and compare with the parameters of MRI and CT diagnostics of this pathology.

The reliability of the results of the study by the claimed method was confirmed in all cases of the study.

Using this method of instrumental diagnostics allows to determine the lateralization of the patella, to identify high-risk groups for the development of diseases of the knee among patients with pain in the knee joint, to determine treatment tactics using non-invasive diagnostic methods.

Claims (1)

The method of ultrasonic determination of the lateral dislocation of the patella, including visualization of the contour of the upper surface of the patella and subsequent acquisition of an ultrasound image using a scanner sensor located transversely on the middle, drawn in the direction from the apex to the base of the patella line 1-1.5 cm proximally above its edge tops with a slope in the countercranial direction at an angle to the frontal plane, selected in the range from 40 to 45 ° from the visualization condition on the resulting slice the contour of the anterior surface of the patella with an acoustic shadow located in the region of the anterior contours of the medial and lateral epicondyle of the femur and with lateral displacement of the acoustic shadow relative to the contours of the epicondyle in this section, so that at least an incomplete contour of the intercondylar recess, including its lower level, is visualized on the image of the obtained slice, a vertical line is drawn through the lower point of this contour, and through the middle of the segment connecting the lateral and medial points Contours patellar farthest from the drawn in a direction from the apex to the base of the midline of the patella, conduct another vertical line, and then determine the magnitude of the lateral dislocation of the patella, measuring the distance between these lines.

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