The high probability of permanent loss of professional fitness and a significant risk of disability of the injured as a result of limb injuries with peripheral nerve damage contribute to both the continuous improvement of surgical techniques on the peripheral nerves, and the implementation of experimental and anatomical studies aimed at developing new ways to restore the lost innervation. Various types of peripheral nerve injuries are observed in peace and wartime victims in 2-6% and 9.8% of cases, respectively. The high degree of disability of patients with the consequences of peripheral nerve injuries requires improvement of diagnostic and reconstructive plastic approaches in this category of patients. A promising method of restoration of the distal part of the crossed nerve with extensive defects of the nerve trunk is its connection with the lateral surface of the intact donor nerve by the end-to-side neurorraphia. The lack of unambiguous views on the nature of reinnervation in this case, even in the presence of single publications on the positive outcomes of such interventions allow us to use this method only in the absence of the possibility of using autonerval transplants to replace extensive defects of peripheral nerves. The purpose of the study: in experiments on laboratory animals to determine the features of modeling trauma of nerve trunks in relation to the development of the main stages of recovery of lost innervation by connecting peripheral nerves by the end-to-side neurorraphia and to determine the range of simple and demonstrative methods of clinical and instrumental control of the functional state of the restored peripheral nerves in a long-term experiment on laboratory animals. Methods. A comprehensive experimental surgical and clinical-instrumental study was performed on 61 laboratory animals (Chinchilla rabbits of both sexes, phenotypically healthy individuals). In the experimental operating room under intravenous anesthesia, modeling of peripheral nerve defect was performed by resection of the total peroneal nerve with a length of 1 cm at the level of the middle third of the thigh. In animals of the studied group (n=39) to restore innervation, the "end-to-side" neurorraphia of the distal portion of the crossed common peroneal nerve with a specially formed defect of the perineural membrane on the lateral surface of the tibial nerve was performed. In the comparison group (n=22) no replacement of the defect of the common peroneal nerve was performed. The follow-up period after experimental interventions ranged from 1 to 290 days. Morphofunctional state of restored nerve trunks was determined by clinical, radiological and electrophysiological methods. Research results. Performing unilateral resections of the common peroneal nerve in laboratory animals (rabbits) with subsequent restoration of the distal portion of the crossed nerve by connecting it by the end-to-side neurorraphia with a nearby intact donor nerve allows to obtain reproducible in the experiment positive results of tissue reinnervation. Indirect assessment of the functional state of the restored nerves is possible using simple and accessible clinical tests, for example, the amplitude of the abduction of the toes of experimental animals in the study of the unconditional reflex of preparation for landing characterizes the conductivity of the common peroneal nerve. When performing experimental studies with multi-stage reconstructive plastic interventions on the peripheral nerves of laboratory animals, the inclusion of radiological methods in the complex of diagnostic measures allows performing in vivo visualization of the surgical intervention area, the restored nerve trunk, as well as the tissues innervated by its branches, which makes it possible to adjust the plan of subsequent morphological studies. Conclusions Performing resection of the common peroneal nerve of laboratory animals (rabbits) at the level of the middle third of the femur as a model of peripheral nerve injury allows to practice the technique of restoration of the distal section of the crossed nerve by connecting it with the adjacent intact donor nerve of the end-to-side neurorraphia. Performing a simple test with the initiation of an unconditional reflex of preparation for landing allows us to qualitatively assess the functional state of the common peroneal nerve in experimental animals. 3. The inclusion of radiological research methods in the program of comprehensive assessment of the peripheral nerves allows to perform their visualization in vivo with the definition of the main morphological characteristics of the restored in experimental reconstructive plastic interventions of nerve trunks.

A simple method for assessing the functional state of peripheral nerves after performing experimental reconstructive-plastic interventions on laboratory animals has been developed. It is proposed to evaluate the functional state of the common peroneal nerve reconstructed in an experiment by comparing the amplitude of the animal’s toes spreading in the study of the unconditional statokinetic landing reflex. A reflex response to the preparation for landing from the pelvic limbs is manifested by flexion in hip joints, extension in knee joints, plantar flexion in hocks, and spreading of toes.Spreading of toes in rabbits is caused by the contraction of the external extensor of the toes innervated by the deep branch of the common peroneal nerve.If the conductivity of the common peroneal nerve is impaired, spreading of the toes on the side of the trauma fails to manifest.The advantages of the proposed test are: high speed set up and ease of implementation, as well as clear demonstration when comparing the operated and the intact limbs of the laboratory animal.

No abstract

An increasing number of injuries with damage of peripheral nerves, including a substantial number of injuries with extensive defects of large nerve trunks, requires improvement in approach to surgical treatment of patients. High-energy impact injuries in peacetime and wartime often lead to persistent violations of musculoskeletal apparatus, a significant part of which is due to injuries of peripheral nerves. During peacetime, various types of peripheral nerve injuries occur in 2-6% of trauma patients. In today’s armed conflicts, various types of peripheral nerve injuries occur in nearly 80% of neurosurgical patients and are mostly of combined injury. Improvements in surgical methods of recovery of lost innervation due to an injury are directly associated with the development of fundamental understanding of the nature of occurring degenerative and regenerative processes in damaged nerve fiber. Nerve suture is only the creation of appropriate conditions that contribute to regeneration of nerve fibers and recovery of lost functions. When extensive defects of nerve trunks exist, connection of distal part damaged nerve with side surface of the intact nerve is the alternative to traditional replacement of extensive defects with nerve grafts. Positive outcomes of such interventions that were seen during tests on laboratory animals led to trials of this method on patients and resulted in a number of positive outcomes as well. Despite the fact that the question of morphological substantiation of reinnervation processes of the distal portion of a damaged nerve is the cause of heated disputes among scientists, some surgeons make attempts to define a set of specific conditions needed to justify the use of end-to-side neurorrhaphy.

Морфологическая характеристика изменений периферических нервов и тканей таргетных зон при соединении периферических нервов по типу «конец-в-бок» в эксперименте А.Ю. Ништ, В.С. Чирский, Н.Ф. Фомин ФГБВОУ ВО Военно-медицинская академия имени С.М. Кирова МО РФ, Санкт-Петербург, РоссияВведение. Перспективным способом восстановления иннервации, утраченной при травмах периферических нервов, является соединение дистального сегмента поврежденного нерва с интактным нервом-донором по типу «конец в бок». Немногочисленные публикации о случаях выполнения данных вмешательств наряду с отсутствием фундаментальных представлений об источнике и механизме восстановления волокон нерва-реципиента, состоянии нерва-донора, а также о полноте реиннервации тканей после подобных вмешательств сдерживают внедрение данного способа в широкую хирургическую практику. Цель исследования -дать морфологическую характеристику изменений нерва-донора и нерва-реципиента, а также оценить морфофункциональные результаты реиннервации мышечной ткани в условиях соединения пересеченного периферического нерва с интактным нервным стволом по типу «конец в бок» в эксперименте на лабораторных животных. Материалы и методы. Исследование выполнено на 79 лабораторных животных (кроликах). У животных экспериментальной группы после моделирования травмы общего малоберцового нерва на уровне середины бедра дистальный сегмент пересеченного нерва соединяли с интактным большеберцовым нервом по типу «конец в бок». В группе контроля после моделирования аналогичной травмы общего малоберцового нерва реконструктивные вмешательства на поврежденном нерве не проводили. Результаты. При исследовании микрохирургической анатомии этапов реконструктивно-пластических вмешательств на периферических нервах, связанных с хирургическими манипуляциями на периневральных футлярах нервных стволов, подтверждена высокая вероятность частичного повреждения нервных волокон, непосредственно прилежащих к периневрию. Результаты морфофункционального исследования периферических нервов и иннервируемых ими мышц свидетельствуют о частичном восстановлении утраченной иннервации за счет соединения дистального сегмента поврежденного нерва-реципиента с интактным нервом-донором по типу «конец в бок» в эксперименте на лабораторных животных. Морфологической основой реиннервации нерва-реципиента в данном случае являются регенерирующие аксоны из состава нерва-донора, неизбежно повреждаемые на этапах микрохирургического вмешательства. Репаративная регенерация волокон нерва-донора обеспечивает как реиннервацию дистального сегмента нерва-реципиента, так и частичное восполнение собственных потерь нерва-донора. Ключевые слова: периферический нерв, травма периферического нерва, мышечная атрофия, восстановление нервов, соединение периферических нервов по типу «конец в бок», регенерация периферических нервов, восстановление иннервации Для корреспонденции: Алексей Юрьевич Ништ. E-mail: nachmed82@mail.ru Для цитирования: Ништ А.Ю., Чирский В.С., Фомин Н.Ф. Морфологическая характеристика изменений периферических нервов и тканей таргетн...