[Neurohistological characteristics of regeneration of the ends of the injured nerve under measured traction]. / Neirogistologicheskaia kharakteristika regeneratsii kontsov povrezhdennogo nerva v usloviiakh dozirovannogo rastiazheniia.

A resection of sciatic nerve in 25 dogs was performed out and the ends of cut nerve were connected by sutures with special apparatus for quantified traction of nerve stumps. 5 days after resection traction was stented at the rate of 0.25 mm twice a day. A histological analysis performed in 5, 12, 19, 26, 33 days after resection an 2-12 months after nerve suture has shown that stress strain effects on intercalation of nerve structures (Ilizarov's effect). Newly formed Schwann chains free of products of axonal and myelin disruption have got a perfect longitudinal orientation and that's why can be considered as an optimum substratum for axonal regeneration.

[The characteristics of osteogenesis under conditions of stretch tension]. / Osobennosti otseogeneza v usloviiakh napriazheniia rastiazheniia.

Structure of rough-fibrillar, netted and laminated bone tissues, formed in distraction regenerates on various stages of leg lengthening, was studied experimentally on dogs, using light, transmission and scanning electron microscopy and electron probe microassay. It was ascertained, that the first two types of tissues belong to the category of provisory, rapidly renewing ones, the volume increase of which is possible not only at the expense of appositional growth but also interstitially. Their formation in the area of the regenerate, more proximally and more distally than the medial layer, provided longitudinal growth of primary osteons forming here and thereby the growth of the whole bone regenerate.

Clinical application of the tension-stress effect for limb lengthening.

For 40 years, the author has been developing a system of orthopedics, traumatology, and limb lengthening using a circular transfixion-wire external skeletal fixator, often in combination with biomechanic methods of stimulating the formation of new osseous tissue within a widening osteotomy distraction site. The factors important for neoosteogenesis after osteotomy include: maximum preservation of extraosseous and medullary blood supply; stable external fixation; a delay prior to distraction; a distraction rate of 1 mm per day in frequent small steps; a period of stable neutral fixation after lengthening; and physiologic use of the elongating limb. For a successful fixator application, the apparatus must be applied with consideration given to the number, size, and location of the rings, the placement and tension on the wires, the technique of wire insertion, the effect of soft-tissue transfixion on limb use, and the prevention of bone and joint deformities caused by countertension in soft tissues. Clinical application of the author's techniques permits stature increase in certain forms of dwarfism, correction of deformities and limb-length inequalities, and stump elongation. For many of these applications, motorized distraction can provide continuous limb lengthening while the apparatus is on the patient.

The tension-stress effect on the genesis and growth of tissues: Part II. The influence of the rate and frequency of distraction.

To assess the influence of both the rate and the frequency of distraction on osteogenesis during limb elongation, a canine tibia was used with various combinations of distraction rates (0.5 mm, 1.0 mm, or 2.0 mm per day) and distraction frequencies (one step per day, four steps per day, 60 steps per day). The distractions were performed after both open osteotomy and closed osteoclasis. Histomorphic and biochemical studies were conducted on the elongated osseous tissue, fascia, skeletal muscle, smooth muscle, blood vessels, nerves, and skin. It was determined that distraction at a rate of 0.5 mm per day often led to premature consolidation of the lengthening bone, while a distraction rate of 2.0 mm per day often resulted in undesirable changes within elongating tissues. A distraction rate of 1.0 mm per day led to the best results. It was also observed that the greater the distraction frequency, the better the outcome. With optimum preservation of periosseous tissues, bone marrow, and blood supply at the time of osteotomy, stability of external fixation, and 1.0 mm per day of distraction in four steps, osteogenesis within the distraction gap of an elongating bone takes place by the formation of a physislike structure, in which new bone forms in parallel columns extending in both directions from a central growth zone. The growth plate that forms under the influence of tension-stress has features of both physeal and intramembranous ossification, yet is neither; instead, the distraction regenerated bone is unique, providing numerous applications in clinical traumatology, orthopedics, and other medical disciplines.

The tension-stress effect on the genesis and growth of tissues. Part I. The influence of stability of fixation and soft-tissue preservation.

To evaluate the optimum conditions for osteogenesis during limb lengthening and to study the changes in soft tissues undergoing elongation, a series of experiments were performed on the canine tibia. The experiments used the transfixion-wire, Ilizarov circular external skeletal fixator in configurations of differing stability of fixation in combination with a second variable, i.e., preservation of the periosteum, bone marrow, and medullary blood supply. Both increased fixator stability, and maximum preservation of the periosseous and intraosseous soft tissues enhanced bone formation during limb lengthening. To assess the role that the direction of the elongation vector plays in osteogenesis, canine tibiae were widened rather than lengthened in a second series of experiments using an Ilizarov apparatus modified for lateral distraction. The new bone formed parallel to the tension vector even when perpendicular to the bone's mechanical axis. As in longitudinal lengthening, damage to the bone marrow inhibits osteogenesis occurring by the influence of a lateral tension-stress vector. In a third series of experiments, half- and full-circumference cortical defects were created in canine tibiae to study the osteogenic potential of the marrow. New bone formed rapidly, even when the marrow was separated from the surrounding periosseous soft tissues by a sheet of polyvinyl chloride, attesting to the importance of marrow element preservation during osteotomy for limb lengthening.

The principles of the Ilizarov method.

The author was the 1987 Sir Robert Jones Lecturer of the Hospital for Joint Diseases Orthopaedic Institute. This article is based on the speech he delivered in that capacity on October 30, 1987, at the Annual Scientific Program of the Alumni Association, supplemented by material he presented at a three-day International Conference on the Ilizarov Techniques for the Management of Difficult Skeletal Problems which was sponsored by HJDOI November 1-3, 1987.

[Ultrastructural characteristics of elastogenesis in the major arteries of the canine hindlimb during leg lengthening]. / Ul'trastrukturnye osobennosti élastogeneza v magistral'nykh arteriiakh tazovoi konechnosti sobaki pri udlinenii goleni.

In mature dogs ultrastructural peculiarities of elastogenesis in femoral and anterior tibial arteries have been studied at various stages of the bone elongation after Ilizarov method. From the end of the 1st week of distraction, metabolic activation of intimal smooth muscle cells is revealed, from the 2d week--in the middle tunic, and on the 5th-6th week--fibroblasts of adventitia of the arteries investigated, directed to biosynthesis of intracellular predecessors of elastin and microfibrils of the elastic fibers. This results in activation of elastogenic processes, elastic structures in all three tunics of the arteries are observed to newly form and rearrange. The factor that stimulates and maintains elastogenesis is strain of extension, that occurs in the vessels during the experiment. Elastogenesis in the major arteries, when the extremity is elongated, has much in common with development of elastic components in the vascular wall in animals during the process of physiological growth.

[Potentials of transosseous osteosynthesis in preventing posttraumatic osteomyelitis in open fractures]. / Vozmozhnosti chreskostnogo osteosinteza v profilaktike posttravmaticheskogo osteomielita pri otkrytykh perelomakh.

An experience with the treatment of 547 patients with open fractures of long tubular bones of extremities is described. The method used for the treatment of the wounds and osteosynthesis gave less amount of complications and better results of the treatment.

[Transosseous osteosynthesis in fractures of bones of the elbow joint]. / Chreskostnyi osteosintez pri perelomakh kostei loktevogo sustava.

The experience with the treatment of 64 patients with fresh fractures of the elbow joint bones by the method of percutaneous osteosynthesis with the Ilizarov apparatus has shown its high efficiency in the treatment of such injuries.