RU2177248C2 - Method for predicting bone tissue formation course - Google Patents

Abstract

FIELD: medicine. SUBSTANCE: method involves examining regenerated bone in the end portions of fractured bone fragments close to the main bone defect after surgical intervention with parameter evaluation following. The examination is carried out by measuring high frequency impedance between transducers set on at least three living tissue areas of the biological object under study. When examining ill extremity, three metal transducers engageable in direct way with the bone tissues are used, the fourth transducer being metal electrode placed on extremity skin surface. When examining healthy extremity, three metal transducers engageable with the bone tissues are used, the fourth transducer being metal electrode placed on extremity skin surface. The ill extremity is subjected to examination at least five times during the whole treatment period. The obtained results are compared to control values being represented by the parameters measured on the healthy extremity. Progressive reduction of parameter differences on the ill and healthy extremity witness favorable osteogenesis development course. The differences being constant or increasing, unfavorable osteogenesis development course is to be predicted. EFFECT: enhanced accuracy of prognosis; low radiation load.

Description

 The invention relates to medicine, namely to traumatology and orthopedics, and can be used to control the formation of bone regenerate during compression distraction osteosynthesis.

 There is a method of evaluating bone formation with lengthening of the limb according to Ilizarov, based on x-ray and ultrasound examination of bone regenerate at different periods of its formation [1].

 However, x-ray studies create a radiation load on the patient's body. Echographic studies solve the problem of radiation safety of the patient, however, during distraction, the regenerate acquires acoustically inhomogeneous properties, which reduces the accuracy of evaluating bone formation. A visual assessment of radiographs and echograms reveals only significant changes in the bone structure. Therefore, the objectification of this data is necessary.

 A known method for predicting the course of bone formation by determining the optical density of the bone by x-ray [2, 3].

 The method is based on the study of the regenerate in at least three sections of the end sections of the fragments in the immediate vicinity of the pseudoarthrosis before and after the operation with subsequent evaluation of the parameters. However, frequent monitoring of bone optical density significantly increases radiation exposure to the patient.

 The objective of the invention is to improve the accuracy of predicting the course of bone formation while reducing radiation exposure.

 This task is achieved in that in a method for predicting the course of bone formation, including filling a bone defect with regenerate and examining bone tissue parameters after surgery, according to the invention, the study is performed by measuring the high-frequency impedance of at least three sections of living tissue of a biological object between sensors made of metal, however, for a diseased limb, three sensors are placed with the possibility of direct contact with bone tissue, and the fourth sensor is on the skin surface This limb, the study of the diseased limb is carried out at least five times during the entire period of postoperative treatment, the obtained results of the measured parameters are compared with the control obtained in symmetrical areas of a healthy limb, for which three sensors are placed with the possibility of contact with the bone, and the fourth on the skin the surface of a healthy limb, with a progressive decrease in the difference in parameters on the diseased and healthy limb, a favorable course of bone formation is predicted, and with increased enii difference or when the permanence predict adverse for bone formation.

 The essence of the invention lies in the fact that during research in the period of postoperative treatment, metal spokes that have constant contact with bone tissue are used to measure the impedance of living tissue of a biological object in a diseased limb. The method provides a quantitative assessment of changes in bone structure, which contributes to the objectification of forecasting.

 The method is as follows.

 For example, patient A. has chronic osteomyelitis of the left humerus. An operation is performed - a resection of a pathologically altered bone. Osteosynthesis according to Ilizarov, while all the spokes in a taut state are fixed on external supports by means of strips made of a solid dielectric (for example, from a press material of the brand AG 4B, fiberglass).

 After filling the bone defect with regenerate, high-frequency impedances between the sensors are measured. The role of the sensors on the diseased limb is performed by knitting needles that have galvanic contact with the bone tissue of bone fragments and a metal electrode placed on the skin surface in the area of the bone defect. The impedance between the sensors is measured, namely, between the spokes that are installed closer to the defect zone, between each of the spokes and the metal electrode. Results are recorded. On a healthy limb, three injection needles are inserted symmetrically into the muscle tissue before contact with the bone.

 Symmetrically to the defect zone, a metal electrode is installed on the skin surface. The magnitude of the high-frequency impedance between the inner needles, between each needle and the metal electrode is measured. The impedance values measured on a healthy limb are taken as healthy controls.

 During treatment, the measurement of impedances on the diseased limb is carried out at least once a month. Comparison of the obtained results with the control.

 With a progressive decrease in the difference in parameters on the diseased and healthy limb, a favorable course of bone formation is predicted, with an increase in the difference or with its constancy, an unfavorable course of bone formation is required, requiring additional treatment and a control examination of the limb.

 The metal electrode is made of stainless steel.

 The impedance measurement is performed using the device "impedance meter BM-507" company TESLA.

 Measurement is carried out at frequencies of 200 - 400 kHz.

 For measuring impedance, it is possible to use a device described in RF patent N 2161903, class. A 61 B 5/0476.

Sources of information
1. E.I. Ermak et al. Echographic, morphological and radiological parallels in the evaluation of bone formation with limb lengthening according to Ilizarov // Genius Orthopedics - 1995 - N 2, p. 53 - 58.

 2. Copyright certificate of the USSR N 1731172, cl. 5 A 61 B 6/00.

 3. S.M. Gulnezarova et al. Densitometry as a method for predicting the course of bone formation during distraction osteosynthesis of joints // Genius Orthopedics - 1996 - N 2 - 3, p. 37 - 38.

Claims (1)

 A method for predicting bone formation turning, including filling a bone defect with regenerate and examining bone tissue parameters after surgery, characterized in that the study is performed by measuring the high-frequency impedance of at least three sections of living tissue of a biological object between sensors made of metal, with three sensors for an injured limb placed with the possibility of direct contact with bone tissue, and the fourth sensor on the skin surface of this limb, pain study of the limb is performed at least five times during the entire period of postoperative treatment, the obtained results of the measured parameters are compared with the control obtained in the symmetrical areas of a healthy limb, for which three sensors are placed with the possibility of contact with the bone, and the fourth on the skin surface of a healthy limb, a progressive decrease in the difference in parameters on the diseased and healthy limb predict a favorable course of bone formation, and with an increase in the difference or with its constancy signify an adverse course of bone formation.