Bulletin of Orthopaedics, Traumatology and Prosthetics, 2010, No. 3; P.59-61
Prof. Ilizarov’s method is one of the most widely accepted and used methods to treat different osseous pathologies. Almost every orthopaedist-traumatologist in the world is familiar with this method and uses it in locomotor apparatus lesions and diseases. Beyond any doubt, implementation of Ilizarov’s method was a revolution in orthopaedics and traumatology, which has elevated treatment of patients suffering from osseous pathology on a novel qualitative level. Nevertheless, disadvantages of transosseous compression distractious osteosynthesis were manifested in clinical cases requiring bone distraction (lengthening). In view of that, alternative methods of bone lengthening using constructions completely submersible into a bone were elaborated, which eliminated disadvantages of external fixation devices (A.Bliskunov , V. Klimovitskiy, V. Dragan (Ukraine) , R. Baumgart, A. Betz Fitbon (Germany) [4, 5], J. M. Guichet Albizzia (France) , S. Hankemeier (2004) , А.Н. Simpson ISKD (USA) ).
Basic disadvantage of external devices includes fixating elements of the construction (spokes and bars) transpiercing the whole lower limb segment through (spoke input: skin – fascias - muscles – fascias – bone, with similar specular reflection at the spoke output). At a first glance, this is not a large problem encountered while solving such a clinical task as fixation of osseous fragments (e.g. in treatment of fractures). Nevertheless, certain complications may appear even in this case. Thus, according to several authors [ 2, 3], results of treating patients with thigh bone fractures in distal area greatly depend on the rate and extent of motion restoration in knee joint. The cause of contractures in knee joint may include non-corrected fragment displacement, further resulting in osteoarthrosis deformans (arthrogenic contractures) or changes in para- and periarticular tissues (myofasciotenodesis, fixation contractures).
, The data by V.М. Demianov, N.V. Vygovsky, and D.А. Orazliev indicate that
contractures appear in 23-100% of cases.
In internal method, the "counter flow" is located inside the bone.
(Fig. 2) The distractious process is concentrated within the system (bone –
intraosseous device). Skin, muscles and fascias are free for stretching (lengthening).
This is an extremely important advantage of internal methods.
Distraction strain is formed in the intramedullary device. Soft tissues around
the bone while responding to distraction with resistance nevertheless do not have
contact area with metal construction, which mediates stretching force. This allows
avoiding a lot of negative moments.
1 – femur
2 - distraction force vector
3 – spokes – the place of "contact conflict" of forces with various vectors
4 - vector of soft tissues resistance force
5 – femur
6 – internal device
7 - distraction force vector
8 - vector of soft tissues resistance force
Comparison in terms of method invasiveness is also required. Actually, invasiveness greatly depends on the extent of artificial constructions immersed into body, as well as their implantation technologies. In external method, it is determined by aggregate volume of spokes located in patient’s body. Implantation technology seems rather simple and bloodless – just a few spoke punctures.
Implantation of internal devices requires certain surgical assesses and bone manipulations, which determines invasiveness of the surgery. At initial stages of internal method development, implantation of intraosseous devices was accompanied with compensatory hemotransfusions.
The internal device works inside the bone. Here, fixation and distraction are united together. But the whole process occurs within the bone. The body “forgets” of artificial construction after the surgery. The device elongates, and the bone grows. Nothing impedes skin, muscles, of fascias.
External device construction determines several body penetrations, which remain permanent (unclosed) during the whole lengthening and restoration period (bone consolidation). Unfortunately, in this case fixation and distraction are antagonistic to each other. Prolonged external fixation is required, which is unfavorable for restoration. Thus, combined methods were elaborated, including internal fixation and external distraction .
The internal methods at their current stage have got over the disadvantages of "early development". The surgeries are low-invasive and relatively safe. Patients’ activities can be started earlier. Intraosseous devices ensure bone growth approaching the natural one. Segment tissues can be easily adapted to stretching as artificial constructions are located inside the bone and do not impede adaptation.
The scheme of counteraction of distractious process forces (distraction caused by artificial constructions and opposite resistance force of tissues) is improved when intraosseous constructions are used. Distractious effort vector is located (concentrated) inside the bone (construction), while opposite resistance forces of segment tissues are intact, free, and located outside the internal devices coverage.
In external constructions, the opposing forces, i.e. metal spokes and soft tissues of limb segment, are in contact-conflict.
Distraction forces provide bone stretching and they naturally predominate over soft tissues resistance forces. As a result along the whole length of the spoke(s) contact with soft tissues of stretching segment their traumatization occurs, which affects rehabilitation process.
Distractious osteosynthesis as an important instrument of modern orthopaedics and traumatology has a great potential for development due to implementation of intraosseous technologies.