Static load distribution in feet parts of 33 normal subjects and 37 patients with shortenings and defects of forefoot was analysed, using “ORTHO-SYSTEM” computer biomechanical unit. It was demonstrated, that foot weight-bearing was disordered in stumps of forefoot with complete absence of its loading. Reconstitution of the forefoot and increase of its loading within 15% resulted in normalization of limb static weight-bearing just in the immediate months after treatment.

197 limb lengthenings were performed in our Department since 1985.
Femur: 87 cases - average gain 8,5 cm (ranging from 4 to 15 cm)
Tibia: 92 cases - average gain 7,3 cm (ranging from 3 to 15 cm)
Humerus: 18 cases - average gain 9 cm (ranging from 8 to 10 cm) 14 fractures were observed after surgery, i.e. 7% of cas-es. Indications for lengthening were: lower Umb: congenital (17 fibular hemimelias, 5 phocomelias and congenital coxa-vara, 26 short statures among then 12 achondroplasias), post-infectious (10) or post-trauma epiphysiodesis and malunion (14).
upper limb: 18 humerus: congenital: humerus varus (2), achondroplasia (12), post-infectious (3) and bone cyst (1).
The femur was involved in 9/87 cases (10%) ; tibia in 3/92 (3,2%) and humerus in 2/18 (11%). Fractures occurred prefe-rentially for large gains (over 7 cm). They were observed early (within 3 months) after apparatus removal: 35 %, or later (between 3 to 6 months): 56 % . One very late fracture occured at 15 months: 5%. They occured at equivalent rates in congenital and other etiologies. However, they occur less in achondroplasia (2 cases).
Anatomically 3 categories were individualized:
1) Transverse fracture with angulation but without overlapping (8 cases, among then 7 femoral) observed early (3 post-op. months). This fracture type is instable and justifies an ESIN (Technique from Nancy).
2) Plastic inflexion: 2 cases of moderate inflexion, stabilized with a cast and 3 cases of large inflexion, needing a new ex-ternal fixator.
3) Overlapping (2 cases): these fractures are irreducible (soft tissues retraction) and must be treated with setting of a new external fixator.
After a review of the literature, and the etiology fractures occurring after lengthening, we conclude, based on our expe-rience, that an angulated fracture needs an ESIN to prevent displacement and overlapping.

A giant-cell tumor was removed and a bone tissue defect was substituted by transportation of bone fragments in 14 patients. Osteogenesis status was controlled using labelled Technephor, and concentration of osteotropic hormones and cyclic nucleotides was studied as well. It was established, that the process of regeneration in oncological patients was lower, than in patients without tumors. Parathyrin amounts were more in oncological patients at osteosynthesis stages. Concentration of calcitonin and somatotropin was considerably less. On the basis of cAMP/cGMP ratio study it was noted, that organotypical reorganization of distraction regenerate was longer, when postresection defects were substituted in comparison with posttraumatic ones.

Investigation of 417 normal children of different age and of 342 ones with congenital retardation of limb growth demonstrated, that contribution of metaepiphyseal growth plates (MEGP) to increase of longitudinal sizes of limb segments decreased in achondroplasia. This decrease is caused by initial retardation of growth and dynamics of muscular elasticity index to a great extent. After elongation of limbs according to Ilizarov making up growth for MEGP area can afford restoration of natural growth of limb elongated segment in children in case of normalization of muscular tension stress amount and maintaining of accelerated blood flow.

Canine tibial regenerates, formed after flexion osteoclasia during stable fixation of fragments with the Ilizarov apparatus, were studied, using methods of scanning electron microscopy and roentgen electron-probe microanalysis. It was established, that newly formed bone trabeculae in the regenerates were closed into themselves and formed a network of round bone lacunae. Primary endosteal osteo-osteoid union was formed and bone callus began forming in the interfragmental space of the regenerates unusually early - quite on 5-th day after surgery. This space was almost completely filled with newly formed bone tissue on 12-th day. By mineralization degree the regenerates approximated the indices of intact diaphysis on 19-th day, though differences were still statistically significant.

Viscoelastic properties and chemical composition of articular cartilage was studied in the dogs, which were subjected to the Ilizarov apparatus application to a leg, with intraarticular infusion of chondroprotector and without it. In the cartilage of operated and contralateral limbs changes developed, consisting in decrease of pliability, increase of mineralization degree, break of ratios between monomeric and aggregated proteoglycanes of cellular matrix. Experimental evaluation of the proposed preparation - stimbone-3 - demonstrated, that its use as intraarticular injections almost completely restored mechanical properties of articular cartilage in case of its degenerative involvements.

Results of regeneration study of skull vault bones under compression, performed between fragments with the Ilizarov apparatus, are presented in the work.

Peculiarities of spatial organization of bone tissue in distraction regenerates of adult dogs at different stages of leg elongation are studied, using scanning electron microscopy. It is established, that regenerating bone tissue acquires a microspongioid structure with formation of closed spheroid lacunae in the parts, adjacent to fragmental ends in the medullary canal of the proximal and distal fragments of elongated bone and in distraction diastasis. Round and closed bone lacunae under the influence of distraction are transformed to longitudinally oriented primary cylinder-shaped osteones in peripheral parts of undermineralized median interlayer proximally and distally. Tops of osteones grow towards each other from the direction of the proximal and distal bone fragments all over the period of distraction. Besides, the regenerates acquire typical zonal structure.

Results of calculations are demonstrated concerning quantitative evaluation of rigidity of fixed wires and rods, used for fixation of fragments in tubular bones and vertebrae in clinical practice. Comparative analysis of rigidity for rods and tightened wires with two supports is shown, practical recommendations are given.

There are two trends of methodological approach to treatment of patients with this pathology at present: the first one is limb prosthetics after amputation or isolation of underdeveloped segments, and the second one is an organosaving trend, including prosthetics of itself, prosthetics after conservative and operative limb preparation. We consider organosaving surgeries for this defect to be the most prospective and humane. Parents of the children with longitudinal tibial ectromelia give preference to limb saving. New effective techniques for stabilization of fibula with respect to femur depending on anatomic variety of the defect were proposed at Russian Ilizarov Scientific Centre “Restorative Traumatology and Orthopaedics” on the basis of modern achievements in the field of transosseous osteosynthesis, as well as methods of limb reconstruction and a special device for their performance, allowing to restore limb weight-bearing in functionally favourable position.

A male patient S., 25 years old, who had Group II invalidism, was treated at RSC “RTO” for posttraumatic tibial defect , complicated by chronic osteomyelitis with marked scarry process of leg and trophic ulcer. The technique for reconstructive tibialization of fibula by formation of its duplication was successfully used in this case. The tibial defect was substituted, segmental shortening was corrected, and limb weight-bearing was restored.

Status of menstrual cycle was observed in 89 women in the process of short limb elongation. Concentration of gonadotropins and sex hormones was determined simultaneously as well as mineral content. It was established, that the most substantial changes in menstrual cycle and hormonal content took place after surgeries in the first days of the follicular phase and that of yellow body.

Actuality of the problem concerning treatment of patients with severe pelvic injuries is substantiated in the work. Technique of transosseous osteosynthesis is described for the above-mentioned injuries. A conclusion is drawn about high effectiveness of the proposed technique for the given category of patients.

The problem of treatment of patients with limb muscular herniae is discussed in this work. A new method is described for treatment of patients with the mentioned pathology.