[Variants of clinical course of Dupuytren's contracture and palmar aponeurosis tissue composition in patients of different age groups.]

For the purpose of comparative analysis of the clinical course of fascial fibromatosis and tissue composition of the palmar aponeurosis in patients of different age groups сase reports and histological surgical material from 179 Dupuytren's contracture patients treated in 2014-2018 were analyzed. Patients were distributed in age groups: the 1st - younger than 50 years, the 2nd - 50-65 years, the 3rd - over 65 years old. In all groups four variants of Dupuytren's contracture clinical course were noted: swift, fast, benign and deffered. The rates of third-fourth levels of contracture in age groups were 50, 54 and 76% respectively. In groups 2 and 3 the volume per cents of hyperplastic connective tissue and adipocytes in palmar aponeurosis were decreased though body mass indexes were increased in comparison with group 1 (p<0,005). The signs of fat tissue vascularity and perivascular inflammatory infiltration were most pronounced in group 1, in group 3 per cent of vessels with adventitial fibrosis was significantly increased. The obtained data may be used for age-oriented treatment protocols and individual prognosis of fascial fibromatosis recurrence and spread.

[INTERRELATION BETWEEN THE PREOPERATIVE MORPHOLOGICAL CHARACTERISTICS OF PERIPHERAL BLOOD AND THE QUALITY OF ENGRAFTMENT OF VASCULARIZED ADIPO-FASCIO-CUTANEOUS FLAPS IN RATS].

The aim of this work was to determine the interrelation between the preoperative blood counts and the quality of vascularized adipo-fascio-cutaneous flap survival. In 10 adult male Wistar rats, a flap with the area of 18 cm2 was formed on the basis of superficial inferior epigastric artery; after a 90 min ischemic period it was replanted. 12 days after operation the quality of flap survival was assessed with computer-assisted planimetry. It was found that the combination of preoperative leukocyte, thrombocyte, neutrophil and eosinophil counts as well as reactive lymphocyte counts close to the maximal reference values increased the probability of epidermolysis.

Morphofunctional Changes in the Tibial and Peroneal Nerves in Shin Lengthening Using High Speed Daily Distraction Technique.

A sustained decrease in the M-response amplitudes of m. gastrocnemius and m. tibialis anterior was revealed during experimental orthopedic shin lengthening in dogs using Ilizarov external fixator with an automated drive (distraction 3 mm/day in 120 steps). Transverse contraction of intrafascicular content (by 13.2%), endoneural hypervascularization (by 28-95%), axonal degeneration and myelin decompactization, and destructive changes of no more than 5% fibers were detected in the tibial nerve. In the peroneal nerve, the contraction reached 17.3%. Endoneurium hypovascularization (by 12%), axonal degeneration and demyelinization, and destructive changes of more than 20% fibers were detected in 6 of 9 experiments.

[HISTOLOGICAL CHANGES IN THE KNEE JOINT SYNOVIAL FLUID IN EXPERIMENTAL MODELING OF OSTEOARTHROSIS AND ORTHOPEDICBONE LENGTHENING IN DOGS].

The experiment was aimed at studying the structural reorganization of the knee joint synovium in dogs with modeling of primary osteoarthrosis (MOP) and tibial lengthening (TL). The methods of light microscopy and histomorphometry of semithin epoxy sections were used to assess the thickness of synovial surface layer, number of synoviocyte layers, characterize the cells, to measure the numerical density of vessels, and to define the changes of the nerves and cell composition of the subsynovial layer. In MOP-group, the predominance of type А synoviocytes, hypovascularity and irreversible changes in the nerves of subsynovial sheath were observed. In TL-group, the diversity of type В synoviocyte forms and sizes, hypervascularity of subsynovial layer and signs of its re-innervation were detected. It is concluded that the hyperplastic synoviopathy is possible in cases of both hypo- and hypervascularization of subsinovial layer.

[STUDY OF CHONDROCYTE PROLIFERATIVE ACTIVITY IN THE CANINE ARTICULAR CARTILAGE DURING LENGTHENING OF THE ADJACENT LIMB SEGMENT].

To assess the effect of orthopedic lengthening on proliferative activity of chondrocytes in the articular cartilage, dosed tibial lengthening by 28 mm was performed in 15 dogs at the rate of I mm/day divided into 4 sessions. Experiment time-points - 28 days of distraction, 30 days of fixation in the apparatus and 30 days after the apparatus removal. Methods of light microscopy of paraffin sections, immunohistochemistry, histomorphometry of semithin epoxide sections were used. At the end of distraction, the preferential concentration of Ki-67 marker was detected in the upper layers of the intermediate zone, while focal distribution was noted in the superficial and deep zones of articular cartilage of femoral condyles. Upon completion of lengthening, a stable increase in the number of chondrocytes was noted in the superficial and intermediate zones but not in the deep cartilage zone as com ared with the intact group (n=5).

[CHANGES OF THE SUPERFICIAL PERONEAL NERVE IN RELATION TO THE FREQUENCY OF HIGH-FRACTIONAL AUTODISTRACTION IN ORTHOPEDIC LENGTHENING OF THE TIBIA IN DOGS WITH A DAILY RATE OF 3 mm].

The experiments on the elongation of the tibia in 18 dogs were performed for 10 days using the Ilizarov apparatus with an automatic drive providing the pace of 3 mm/day for 120 moves (group 1) and 180 moves (group 2). The impact of fractionation of distraction on the structure of the peroneal nerve was estimated. In group 1, perineurium micro-injuries and endoneural blood vessel destruction were detected. In group 2, perineurium preserved its integrity and fine-lamellar structure, endoneural blood vessels were also preserved, however, the decrease in the total area of nerve fiber bundles was more pronounced. Morphometric analysis of the preserved myelinated nerve fibers 60 days after the cessation of distraction indicated less marked axonal atrophy and better myelination in group 2.

[Histomorphometric charactheristic of skeletal muscle regenerating after a closed partial crush injury].

To evaluate the degree of skeletal muscle regeneration in 15 adult Wistar rats, the closed partial crush injury of anterior tibial muscle was modeled. The study was performed using the methods of light microscopy and computer-assisted morphometry of semithin sections. The continuity of the crushed muscle fibres (MF) was restored by day 21 after the injury. After 90 days endomysial fibrosis was substantially reduced and its vasculairity increased; the variability of MF diameters was restored, however the branched structure and myopathic changes of the regenerated tissue persisted and were presumably associated with an incomplete reinnervation of the damaged intramuscular nerves.

[Structural reorganization of the main joint components during the experimental modeling of osteoarthrosis with reduced blood supply].

The reactive changes in the knee synovium, articular cartilage, and subchondral bone during osteoarthrosis modeling were studied in dogs (n = 5). The results of histomorphometry, scanning electron microscopy, and electron probe microanalysis have demonstrated that the osteoarthrosis model used (femoral artery ligation and the knee immobilization) lead to marked synovitis, axonal atrophy and nerve fiber degeneration in subsynovial nerves, as well as synovial membrane hypovascularization. Subchondral bone vascularization was shown to deteriorate, while calcium content was reduced. Destructive changes were detected in the articular cartilage. Chondrocytes of the intermediate zone which were equidistant from vascular and synovial sources of supply appeared to be the most vulnerable. The changes described are the consequences of the disturbed interactions of the main joint components indicating the reduction of synthesis with a predominance of catabolic processes.

[Changes in the knee joint synovial membrane and articular cartilage during shin lengthening by autodistractor at increased daily rate].

Light microscopy and computerized morpho- and stereometry were used to examine the changes in the knee joint articular cartilage and synovial membrane studied during experimental canine shin lengthening by 15% of initial length by autodistraction at increased rate - 3 mm per day with switching on the automatic device 120 times. By the end of distraction period (10 days) the destructive changes in articular cartilage were more marked in the superficial and deep zones, synovitis of moderate and mild degree was observed accompanied by the destructive changes in the blood vessels and nerves of the subsynovial layer. Regeneration of articular cartilage was incomplete, and regressive neurovascular changes persisted in synovial membrane 30 days after the device removal. Comparison of these results with the previous data obtained using the distraction rate of 3 mm applied 180 times, leads to the conclusion, significant for functional prognosis, of the worsening the parameters of structural cartilage recovery in case of distraction pitch increase from 0.017 mm to 0.025 mm.

[The effect of cerebrolysin on the regeneration of the peripheral nerve depending on the scheme of paraneural administration].

An experimental morphological study in 56 animals has been performed in order to analyze the effect of cerebrolysin on the dynamics and long-term results of peripheral nerve regeneration after the transection and microsurgical suturing depending on the scheme of the preparation of paraneural infusion. The regeneration process was evaluated after 2.5; 4; 6 and 12 months. There was a stimulating effect of the preparation on the regenerative growth and differentiation of nerve fiber axial cylinders, vascularization of the distal segment of regenerating nerve and the trophic condition of myelin-forming Schwann cells. When the preparation is used according to the prolonged scheme, the effect persists for up to 10.5 months after the end of paraneural injection course.

[State of lower alveolar and mental nerves by mandible fractures healing under transbone osteosynthesis].

Fracture of mandibular body at the level of P3-P4 with symphysis rupture was modeled, reposition and transosseous osteosynthesis with a specially developed device were performed under anesthesia in the operating room in 17 adult mongrel dogs in order to specify the pathogenesis and the dynamics of injury and jaw nerve regeneration. It has been established, that the arrangement of the neurovascular bundle in medullary canal predetermines the development of acute and chronic compression-and-ischemic neuropathy even if accurate reposition of bone fragments takes place. The histological signs of nerve fiber regeneration, the loss of the quantity of myelin-free nerve conductors and the retrograde spreading of degenerative changes in myelinized nerve conductors, including regenerating ones, have been found beginning from 4 weeks after injury. It has been concluded, that spontaneous nerve regeneration in case of mandibular fractures should be actively supported by neuroprotective, anti-edematous and anti-inflammatory therapy.

[Morphometric evaluation of the effectiveness of post-traumatic peripheral nerve regeneration after a single and repeated courses of electrostimulation].

Sciatic nerve (SN) transection and microsurgical suture were performed in 41 dogs to assess the effect of electrostimulation (ES) on peripheral nerve regeneration. 23 dogs served as a control group, ES of the spinal cord and SN was made with alternating current of 50-Hz frequency in 18 dogs: in 13 dogs one course of 18 sessions was performed within the period of 1-2.5 months after surgery (ESL1), in 5 dogs two courses were performed: the first one--in a similar time interval, the second one--within 6-7.5 months after surgery (ES2). The mean diameter of myelinated fibers (MF) after 2.5, 4, 6, and 12 postoperational months for ES1 was significantly greater than the control values, mainly due to the increase of axonal diameter. After 12 months, the tendency towards the restoration of MF diameter bimodal distribution was marked in ES2, and, to a lesser degree, in ES1. Thus, it was found that ES effectively activates the regeneration and differentiation of MF, but leads to their relative hypomyelination.

[Peculiarities of sciatic nerve endoneurium cellular composition in hip distraction osteosynthesis in dogs].

Using light and electron microscopy, sciatic nerve endoneurium cellular content was studied in 14 adult mongrel dogs subjected to hip elongation for 28-35 days after osteotomy. For light microscopy, semithin sections were prepared. The application of an automated image analysis has demonstrated a moderate increase in macrophage, fibroblast and mast cell content, which remained undetected during visual examination. The morphofunctional state and the distribution of these cells is suggestive of their participation in the extracellular matrix synthesis and remodeling, angiogenesis control, blood flow and endoneurial fluid content regulation in the process of peripheral nerve structural adaptation to extremity elongation.

[Types of coaptation of nerve fiber bundles and effectiveness of the nerve suture]. / Tipy koaptatsii puchkov nervnykh volokon i rezul'tativnost' shva nerva.

Experiments in 26 dogs were carried out in order to analyze the quality of comparing the nerve fiber bundles, morphometrical and functional parameters of regeneration after the restoration of the nerve with a standard epineural microsurgical suture and by an original method including the coaptation of the freshened ends by a relaxation transneural suture followed by epiperineural microneurorrhaphy. Five variants of the comparison of the nerve fiber bundles in the suture zone are described. The results of expert assessments and computed morphometry allowed to register higher indices of regeneration and differentiation of nerve fibers.

[Homeostasis and paravasal damper structures in intact and damaged nerves and long tubular bones]. / Vliianie transrektal'noi mikrovolnovoi gipertermii na gemodianmiku i sostoianie keltochnykh membran predstatel'noi zhelezy pri khronicheskom prostatite.

Sciatic and tibial nerves and a femoral osteotomic area were investigated in experiments on 36 adult mongrel dogs during neutral and distractional osteosynthesis. Histological and X-ray studies, computer-assisted image analysis, and statistical methods were used. The morphological basis of hemodynamic features of the nerves and long tubular bones was characterized. The mechanisms responsible for perivascular osteogenesis in the bone marrow cavity and for hypertrophy of perineural cell paravasal spongy structures in the nerves were studied as compensatory and adaptive responses to changes in the hemodynamical components of homeostasis after bone injury and during extremity stretching.

Reactive properties of epi- and perineurium: experimental and morphological basis for nerve suture technique.

Epi- and perineurium were examined in vitro and during regeneration after mechanical damage. Epithelial type of culture growth and reparative regeneration of the perineurium were established, connective tissue of the epineurium served as the substrate and trophic factor in these processes. We used histogenetic method of coaptation and of epi- and perineural micosutures in a damaged nerve trunk.