RU2657945C1 - Method for predicting the need for re-surgery after osteosynthesis of the calcaneus - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: invention relates to medicine, namely traumatology and orthopedics, can be used to predict the need for re-surgery after osteosynthesis of the calcaneus. Conduct an examination of the patient in the preoperative period. Remote multi-position infrared thermometry is performed to determine the proximal-distal gradient. Segmental manometry is carried out with the definition of an ankle-brachial index. Transcutaneous basal oxygen tension is also measured for the first orthostatic sample (OrtPp). Determine its plateau after the first orthostatic test, with the second orthostatic test, the difference between the basal value and the second orthostatic test, the plateau after the second orthostatic test. Linear discriminant functions F1 and F2 are then calculated according to the claimed formulas. Then obtained values of the first and second discriminant functions are compared. In this case, the function whose value is greater indicates that the patient belongs to the corresponding group.

EFFECT: method allows to accurately predict the need for repeated surgery after osteosynthesis of the calcaneus due to the evaluation of the most significant indices.

1 cl, 1 dwg, 4 tbl, 2 ex

Description

The invention relates to medicine, namely to traumatology and orthopedics, and can be used to predict the need for repeated surgical interventions, after open reposition and internal fixation (ORIF) of a calcaneus fracture in the presence of chronic circulatory disorders of the lower extremities, in the event of purulent complications in operational access area.

Using extended lateral access for open reposition of calcaneal fractures allows to achieve anatomical reposition of fragments of articular surfaces and subsequently perform internal fixation with a special plate [9]. Surgical treatment of patients with calcaneus fractures, which does not take into account the peculiarities of blood supply to the lower extremities and the accompanying pathology in these patients, in almost 30% of cases leads to complications in the early postoperative period [12]. In some cases, patients have diseases and risk factors that lead to circulatory disorders of the distal parts of the lower extremities, including in the area of planned surgical access (chronic obliterating diseases of the arteries of the lower extremities, tobacco smoking, etc.) - suggesting an unreasonable scientific refusal extended lateral access in favor of minimally invasive surgical, or even conservative treatment, condemning the patient to early primary arthrodesis in the subtalar joint [10, 11].

The importance of predicting the need for repeated surgical interventions after ORIF of the calcaneus is determined by the fact that such a forecast allows timely correction of the treatment and diagnostic tactics, volume and expediency of surgical treatment of patients with calcaneus fractures amid chronic circulatory disorders of the lower extremities.

In clinical practice, early prognosis of healing options for the surgical wound and the need for repeated revision surgery after ORIF of the calcaneus are based on the patient’s age, the presence of smoking, peripheral vascular disease, the nature of the fracture according to the Sanders classification, the condition of the soft tissues, the experience of the surgeon, etc. [ 1, 5-8].

Lantukh T.A. et al. (2014) were involved in assessing the risk of developing surgical complications in the surgical treatment of intraarticular calcaneus fractures [2]. However, the authors did not substantiate the feasibility and volume of instrumental studies of patients of this category against the background of peripheral circulation disorders.

Thus, in these works, the task of predicting the need for repeated surgical interventions after osteosynthesis of the calcaneus in patients with calcaneus fractures in the presence of chronic circulatory disorders of the lower extremities is not solved.

In order to objectify the data obtained, as well as determine the volume of surgical intervention, the appropriateness of the use of drug and non-drug therapy during inpatient treatment, a number of instrumental studies are necessary, namely: radiography of the calcaneus and computed tomography of the calcaneus.

In addition, for an objective examination of the blood circulation of the zone of the proposed surgical intervention, it is necessary to carry out such studies as: remote infrared polypositional thermometry (DIPT), segmentary manometry with the determination of the ankle-brachial index (LPI) and transcutaneous oximetry (TroC).

When examining the blood circulation of the zone of the proposed surgical intervention, it should be emphasized the importance of evaluating the compensatory capabilities of the microvasculature during functional tests with recording parameters by the TROk method. The most common are orthostatic tests (OrtPr), the results of which are recorded after raising the lower limb (first Ortr) in a supine position for 30-45 for 3-6 minutes and lowering the lower limb for 3-6 minutes (second Ortr) [4] .

The well-known "Method for predicting postoperative suppuration of the wound" [3], dedicated to the forecast of suppuration of the wound based on laboratory criteria. The essence of this method lies in the fact that the level of malondialdehyde and the activity of superoxide dismutase are determined in the patient’s blood before and after surgery for 4-5 days. With an increase in the concentration of malondialdehyde compared with preoperative data and a decrease in the activity of superoxide dismutase or maintaining approximately the same values as before the operation, postoperative suppuration of the wound is predicted. Using the method provides a simplification of the study, which can be reproduced in any biochemical laboratory, while increasing the reliability of the study by identifying predictors of inflammatory tissue damage, rather than indirect signs of this damage.

The disadvantage of this method is the absence of any other analyzed, including anamnestic criteria and data on an objective assessment of blood circulation in the area of intended access, which does not allow for accurate prediction of the need for repeated surgical interventions after osteosynthesis of the calcaneus in patients with its fractures.

Closest to the proposed invention is the "Scale of risk assessment of the possible surgical treatment of calcaneus fractures ABCDEF" [2].

The following criteria or parameters are used as assessed with a prognostic purpose and assigned a point score: age, blisters (blisters, conflicts), concomitant diseases (related or not related to taking medications), tobacco smoking, trauma energy, the number of intraarticular fragments (based on Sander's classification). According to the results of the total points, a possible outcome is predicted, therefore - a variant of therapeutic tactics.

The disadvantage of this method is the lack of accuracy of forecasting. This is due to the fact that the forecast is based on empirical analysis (objective research data is not analyzed), the diagnostic effectiveness of the evaluated criteria and factors is not determined, and also because the factors taken into account as suppuration risk forecast criteria do not allow reliable early prediction, because they are not mathematically sound and are mnemonic. Moreover, this method does not take into account other, obviously significant factors and criteria - the results of an objective examination of the blood circulation of the zone of the alleged surgical intervention.

Thus, this method for predicting the nature of healing of the postoperative wound and the need for repeated surgical intervention (PCV) after osteosynthesis of the calcaneus is not reasonable in relation to a particular patient, does not use accessible modern methods of examination. In addition, the prototype is dedicated to the selection for surgical treatment in principle, and not the prediction of an early postoperative result, which does not provide accuracy in relation to the prognosis.

The technical result to which the present invention is directed is to increase the accuracy of predicting the need for PCV after osteosynthesis of the calcaneus from expanded lateral access against a background of chronic circulatory disorders of the lower extremities of various etiologies with the possibility of subsequent correction of therapeutic tactics.

The technical result is achieved by the fact that a method for predicting the need for PCV after calcaneus ORIF, including examining a patient in the preoperative period, according to the invention, is carried out on the basis of a PCV need assessment, for which remote polypositional infrared thermometry with proximal-distal gradient (PDG) is determined , then conduct segmental manometry with the determination of LPI, then perform TrOc, measuring the transcutaneous oxygen tension both basal and at the first Oh Ortpr, its plateau after the first orthostatic test, at the second orthostatic test, the difference between the basal value and the second orthostatic test, the plateau after the second orthostatic test, then linear discriminant functions are calculated by the formulas

F1 = -97.8556 + 29.7001 * rtr + 101.6612 * abi-0.0459 * toll-0.1662 * ponk + 1.0880 * pall-1.8754 * dtrp + 0.5974 * pfin,

F2 = -94.5315 + 29.2303 * rtr + 100.7026 * abi-0.5313 * toll-0.5118 * ponk + 1.5190 * pall-2.2998 * dtrp + 0.6757 * pfin,

where F1 is the first classification discriminant function, corresponds to a group of patients who do not require PCV;

F2 - the second classification discriminant function, corresponds to the group of patients requiring PCV;

rtr — PDH, ° C;

abi - LPI, rel.

torb — basal value of the oxygen level at TrOc, mmHg;

toll - oxygen level at the first Ortpr, mm Hg;

ponk - oxygen level plateau after the first Ortpr, mmHg;

pall - oxygen level of the second Ortpr, mm Hg;

dtrp - the difference in oxygen levels between the basal value and the second Ortpr, mm Hg;

pfin - plateau of the oxygen level after the second Ortpr, mm Hg,

Then, the obtained values of the first and second discriminant functions are compared, while the function, the value of which is greater, indicates that the patient belongs to the corresponding group.

The development of a mathematical multidimensional model for predicting the need for PCV in connection with the development of purulent complications can be considered as a natural result of the need for conducting PCV after ORF of the calcaneus from extended lateral access against the background of chronic circulatory disorders of the lower extremities of various etiologies.

To achieve this goal, we used discriminant analysis - a multidimensional statistics method used to solve classification problems, which allows us to attribute an object with a specific set of features to one of the known classes.

In order to select the group of the most informative features included in the final models, the informative value of each feature was estimated by the method of one-way analysis of variance, their expert assessment was made, a number of models with a different set of features were tested.

The relationship between the occurrence of complications and the need for PCV with the indicators measured in the course of our study, assessed in quantitative and ordinal scales, was assessed using univariate analysis of variance. The decomposition of the dispersion of indicators into components was studied:

- variance due to the influence of a controlled factor (a variant of the emergence of the need for PVC and complications and: no or yes);

- variance caused by uncontrolled, random factors and measurement errors.

The degree and significance of the influence on each of the indicators and, accordingly, the relationship with this quantitative indicator were determined by the proportion of variance due to the controlled factor. The results of the analysis of variance for informative signs of forecasting the need for conducting PCV are shown in table. one.

where rtr is the PDH, ° C;

abi - LPI, rel.

torb — basal value of the oxygen level at TrOc, mmHg;

toll - oxygen level at the first Ortpr, mm Hg;

ponk - oxygen level plateau after the first Ortpr, mmHg;

pall - oxygen level of the second Ortpr, mm Hg;

dtrp - the difference in oxygen levels between the basal value and the second Ortpr, mm Hg;

pfin — plateau of the oxygen level after the second OrtPr, mmHg

Analysis of the results of analysis of variance shows that to construct a discriminant model for predicting the probability of performing PCV, a number of indicators can be used that have a statistically significant relationship with predicting the need for PCV. The closest relationship was found with basal oxygen levels at TrOK (F = 41.254; p <0.0001), oxygen levels at the first OrtPr (F = 62.323; p <0.0001), and the oxygen level plateau after the first OrtPr (F = 44.569 ; p <0.0001), oxygen level at the second Ortpr (F = 85.380; p <0.0001), the difference in oxygen levels between the basal value and the second Ortpr (F = 51.091; p <0.0001), the plateau level oxygen after the second Ortpr (F = 88.907; p <0.0001). Somewhat less indicators such as PDH (F = 8.764; p <0.01) and LPI (F = 5.266; p <0.05).

The final discriminant forecasting model for the need for conducting PCVs contains 7 variables listed in Table. 2.

The obtained model for predicting the need for PCV is statistically significant (criterion F (7.66) = 6.232; p <, 00001).

The most informative indicator for predicting the need for PCV in the obtained discriminant model, thus, was the oxygen level at the first OrtPr (p <0.01). This variable has the largest intergroup and intragroup dispersion ratios.

During the canonical analysis, one canonical linear discriminant function (CLDF) was obtained with a significance level of p <0.001 (Pearson's chi-square test - 34.76; number of degrees of freedom df = 7). The nature of the factor structure of the canonical function (Table 3) made it possible to interpret it as a factor in the oxygen level during the first OrtPr: the closest correlation between this canonical function was identified with this variable (r = 0.92).

Under the condition of equal a priori probability that the patient belongs to the considered groups, linear classification discriminant functions are obtained

F1 = -97.8556 + 29.7001 * rtr + 101.6612 * abi-0.0459 * toll-0.1662 * ponk + 1.0880 * pall-1.8754 * dtrp + 0.5974 * pfin,

F2 = -94.5315 + 29.2303 * rtr + 100.7026 * abi-0.5313 * toll-0.5118 * ponk + 1.5190 * pall-2.2998 * dtrp + 0.6757 * pfin,

where rtr is the PDH, ° C;

abi - LPI, rel. units;

toll - oxygen level at the first Ortpr, mm Hg;

ponk - oxygen level plateau after the first Ortpr, mmHg;

pall - oxygen level of the second Ortpr, mm Hg;

dtrp - the difference in oxygen levels between the basal value and the second Ortpr, mm Hg;

pfin — plateau of the oxygen level after the second OrtPr, mmHg

The first classification discriminant function corresponds to a group of patients not requiring PCV, the second - to patients requiring PCV.

For practical application of the obtained discriminant model, the calculation of the values of these classification functions according to the results of a patient examination is used. A function whose value turns out to be greater indicates a group whose probability of belonging to a patient is higher.

The claimed method is illustrated by the following illustrations:

In FIG. 1 shows a scale for assessing the risk of need for PCV after ORIF calcaneus fracture by the value of the canonical discriminant function - CLDF;

A method for predicting the need for PCV after calcaneal ORIF is as follows: the patient is calculated PDH after DIPT. Next, conduct segmental manometry with the determination of LPI and transcutaneous oximetry. After determining the basal level of oxygen, OrtPr is performed, measuring and fixing the oxygen level at the stages of: during the first Ortr, oxygen plateau after the first Ortr, oxygen level of the second Ortr, the difference in oxygen levels between the basal value and the second Ortr, oxygen level plateau after the second Ortr . Then, using the values obtained from the analysis results, linear classification discriminant functions are calculated according to the following formulas:

F1 = -97.8556 + 29.7001 * rtr + 101.6612 * abi-0.0459 * toll-0.1662 * ponk + 1.0880 * pall-1.8754 * dtrp + 0.5974 * pfin,

F2 = -94.5315 + 29.2303 * rtr + 100.7026 * abi-0.5313 * toll-0.5118 * ponk + 1.5190 * pall-2.2998 * dtrp + 0.6757 * pfin,

where rtr is the PDH, ° C;

abi - LPI, rel. units;

toll - oxygen level at the first Ortpr, mm Hg;

ponk - oxygen level plateau after the first Ortpr, mmHg;

pall - oxygen level of the second Ortpr, mm Hg;

dtrp - the difference in oxygen levels between the basal value and the second Ortpr, mm Hg;

pfin — oxygen level plateau after the second OrtPr sample, mmHg

Then, the obtained values of the first and second discriminant functions are compared. The function, whose value is greater, indicates that the patient belongs to the corresponding group of patients who do not or need PCV after ORIF calcaneal bone fracture in the presence of chronic circulatory disorders of the lower extremities.

A method for predicting the need for repeated surgical interventions after osteosynthesis of the calcaneus is illustrated by the following examples:

Example 1

Patient T., 44 years old, was admitted for a closed intra-articular impression fracture of the right calcaneus with displacement of fragments. Denies smoking. According to the patient, he is not registered with a vascular surgeon. The injury was healed as a result of a fall from a height of more than 2 meters. When walking notes pain in the calf muscles 30 minutes after the start of movement. When accelerating walking with the transition to running - a feeling of cramps in the calf muscles. A lack of symmetry and a decrease in the hairline of the legs were revealed. The skin of both legs and feet is pale. The pulsation of the popliteal artery and dorsal artery of the foot of the right lower limb is reduced. The patient has been an active smoker for 14 years.

9°). СКТ заднего отдела стопы - не выполнено. По классификации Фонтейна-Покровского IIa ст.Upon admission, a general clinical and radiological examination was performed. Fracture is classified as type II according to Kaplan's classification (angle

9 °). SKT of the hindfoot - not performed. According to the classification of Fontaine-Pokrovsky IIa Art.

After 5 days from receipt, ORIF was performed from extended lateral access with plastic autograft from the iliac wing.

4 days after the ORIF revealed: inflammation of the edges of the postoperative wound. Against the background of the treatment, which includes: changing aseptic wipes over the postoperative wound, antibiotic therapy, anticoagulants, antihypoxants and drugs that improve the rheological properties of blood, as well as hyperbaric oxygenation sessions - healing by secondary intention. Sutures were removed on the 11th day after the operation. The number of c / d - 17. The total period of disability - 3.5 months.

Research Results:

rtr - 1.60 ° C; abi - 1.01; toll - 18; ponk - 29; pall - 27; dtrp - (-) 1; pfin - 25.

Using the above formulas for calculating classification discriminant functions, the following values were obtained: F1 = 93.182372 and F2 = 89.746306. The function corresponding to the group of patients who do not need PVC is of greatest importance.

Thus, on the basis of the conclusion of the developed method, this patient has a low probability of requiring PCV. The absence of PCV confirms the prognosis - the patient did not have PCV.

Example 2

Patient K., 55 years old, was admitted for a closed intra-articular impression fracture of the left calcaneus with displacement of fragments. Injury received while jumping from scaffolding (up to 2 meters) 1 hour before admission to the hospital. According to the patient, three years before this visit to the hospital, in the clinic at the place of residence the diagnosis was made: obliterating atherosclerosis of the arteries of the lower extremities. When walking notes pain in the calf muscles after 10-15 minutes from the start of movement. A decrease and violation of the symmetry of the hairline of the skin of the legs was revealed.

Upon admission, a general clinical and radiological examination was performed. Fracture is classified as type II according to the Kaplan classification. According to the classification of Fontaine-Pokrovsky - IIa Art. A closed manual reduction of the calcaneus was performed, with gypsum longitudinal immobilization. SKT of the hindfoot - not completed. Consultation of a vascular surgeon has not been appointed.

The period from receipt to surgery is 8 days. In the early postoperative period, a complication in the form of marginal necrosis developed. On the 21st day after ORIF, the area of marginal necrosis = 8 cm ² . Moderate marginal epithelization. Repeated surgery was performed - revision of the postoperative wound, necrectomy. The wound healed by secondary intention after 23 days from the time of PCV. The number of c / d - 48. The total period of incapacity for work - 4 months.

Research Results:

rtr - 3.0 ° C; abi 0.80; toll - 11; ponk - 19; pall - 20; dtrp - (-) 3; pfin -17.

Using the above formulas for calculating classification discriminant functions, the following values were obtained: F1 = 106.75256 and F2 = 106.91928. The function corresponding to the group of patients requiring PCV took on the greatest importance.

Thus, on the basis of the conclusion of the developed method, this patient is highly likely to need PCV. Performing PCV confirms the prognosis - the patient had PCV.

Verification of the obtained model was carried out on the basis of recognition by the model of an existing group of patients (Table 4).

The efficiency of the obtained model is 93%, which confirms the possibility of a sufficiently high-quality forecast of the need for PVC.

An analysis of the matrix of the factor structure of canonical variables, the coordinates of the centroids of the groups under study, as well as the coefficients of the canonical linear discriminant function (CLDF) shows that in favor of the high need for PCV are: high values of the oxygen level of the second Ortr and oxygen level plateau after the 2nd Ortr, and also low values of PDH, LPI, oxygen level at the first Ortr, plateau of the oxygen level after the first Ortr and the difference in oxygen levels between the basal value and the second Ortr.

The construction of KLDF allows us to offer a risk scale for PCV. KLDF is calculated as follows:

KLDF = -2.92032 + 0.24117 * rtr + 0.49211 * abi + 0.24917 * toll + 0.17745 * ponk-0.22125 * pall + 0.21787 * dtrp-0,04021 * pfin,

where rtr is the PDH, ° C;

abi - ankle-brachial index, rel.

toll - oxygen level at the first Ortpr, mm Hg;

ponk - oxygen level plateau after the first Ortpr, mmHg;

pall - oxygen level of the second Ortpr, mm Hg;

dtrp - the difference in oxygen levels between the basal value and the second Ortpr, mm Hg;

pfin — plateau of the oxygen level after the second OrtPr, mmHg

Risk assessment in accordance with the obtained coordinates of the centroids of patient groups with the probability of performing PCV after calcaneus ORIF is carried out as follows (see Fig. 1): on the axis of the selected discriminant canonical function with its value less than -1.53, the risk of requiring PCV is high : relative risk (RR), calculated from the assessment of the available observation matrix, was 25.8. With KLDF values ranging from -1.53 to 0.42, the risk of need for PCV is moderate (RR = 4.8). Minimum risk (RR = 0.03) - with KLDF values of more than 0.42. Calculation of KLDF for patient T. (example 1) showed a high risk (KLDF = -1.45) of the need for PCV, which coincides with both the assessment of classification LDF and the conduct of PCV in the early postoperative period after open reduction and internal fixation (ORIF) calcaneus fracture.

Thus, the proposed method for predicting the need for PCV after calcaneal ORIF allows, on the basis of calculating PDG, calculating the LPI, performing TroC, to accurately assess the risk of PCV in the early postoperative period after ORIF calcaneus fracture.

Thus, the proposed method for predicting the need for PCV after calcaneal ORIF allows, based on the calculation of PDH, calculation of LPI and TroC, to accurately assess the risk of complications requiring PCV in the early postoperative period after ORIF calcaneus fracture, determine the appropriateness of surgical treatment using enhanced lateral access and the need for pharmacological correction in the pre- and postoperative period with sessions of hyperbaric oxygenation.

The proposed method for predicting the need for repeated surgical interventions after osteosynthesis of the heel bone is economical and can be recommended for inclusion in the mandatory examination list for all patients who are planning ORIF fracture of the heel bone.

Information sources

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Claims (14)

A method for predicting the need for repeated surgical intervention after osteosynthesis of the calcaneus, including examining the patient in the preoperative period, characterized in that the prediction is based on an assessment of the need for repeated surgical intervention (PCV), for which remote polypositional infrared thermometry is performed with proximal-distal determination gradient (PDG), then conduct segmental manometry with the determination of the ankle-brachial index (LPI), s thereby measure the transcutaneous oxygen voltage (TrOc) both basal and at the first orthostatic test (OrtPr), its plateau after the first orthostatic test, at the second orthostatic test, the difference between the basal value and the second orthostatic test, the plateau after the second orthostatic test, then calculate linear discriminant functions by the formulas F1 = -97.8556 + 29.7001 * rtr + 101.6612 * abi-0.0459 * toll-0.1662 * ponk + 1.0880 * pall-1.8754 * dtrp + 0.5974 * pfin, F2 = -94.5315 + 29.2303 * rtr + 100.7026 * abi-0.5313 * toll-0.5118 * ponk + 1.5190 * pall-2.2998 * dtrp + 0.6757 * pfin, where F1 is the first classification discriminant function, corresponds to a group of patients who do not require PCV; F2 - the second classification discriminant function, corresponds to the group of patients requiring PCV; rtr — PDH, ° C; abi - LPI, rel. units; torb — basal value of the oxygen level at TrOc, mmHg; toll - oxygen level at the first Ortpr, mm Hg; ponk - oxygen level plateau after the first Ortpr, mmHg; pall - oxygen level of the second Ortpr, mm Hg; dtrp - the difference in oxygen levels between the basal value and the second Ortpr, mm Hg; pfin - plateau of the oxygen level after the second Ortpr, mm Hg, then, the obtained values of the first and second discriminant functions are compared, while the function, the value of which is greater, indicates the patient belongs to the corresponding group.

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