Melnyk I. Differential approach to the internal fixation and rehabilitation treatment of fractures of the lateral condyle of the tibia

The dissertation provides a new approach to the solution of important scientific question - the improvement of the lateral tibial condyle fractures treatment results. The study is based on simulation-computer modeling and finite element method of the lateral tibial condyle fractures and different variants of osteosynthesis. Analysis of clinical manifestations, anamnestic data, x-ray parameters and comparative analysis of the treatment efficiency of 32 patients (study group), who underwent osteosynthesis of bone fragments after a preliminary consideration of the stress-strain state of the latches and 36 patients in whom the osteosynthesis was performed without preliminary considering the mechanical properties of the used clips. A comparative analysis of stress-strain state of the lateral condyle of the tibia after osteosynthesis with the steel screws, L- and LCP plates, nylon bolts and a compound osteosynthesis. The biomechanical rationale of the load in a stable functional osteosynthesis of bone fragments in fractures of the lateral condyle of the tibia stainless steel screws to 30% model withstands a load of 1/3 of body weight, 60% of the model is ensured with a load of 1/2 of body weight, or a force of 375 N. When LCP plate osteosynthesis under 30 % model of a fracture of the lateral condyle of the tibia meets the criteria of a stable functional osteosynthesis with a load of up to 750 H (full body weight), in terms of the 60 % model - load up to 572,34 Н (76% of body weight). When osteosynthesis L-plate at 30 % model is fully consistent with the conditions of a stable functional osteosynthesis under all levels of load, and 60 % model stable functional osteosynthesis is provided at a load of 527,64 Н (70% of body weight). Osteosynthesis of bone fragments polyamide bolts or polyamide steel bolt and screw are not shown, because even at a load of 250 N (1/3 body weight) is not provided stable fixation of bone fragments. The scheme of rehabilitation treatment, which consists in applying graduated weight bearing and flexion in the knee joint, is an effective method of treatment of patients with the lateral tibial condyle fractures. Based upon the conducted biomechanical research we have developed a differentiated approach to the choice of the lateral tibial condyle fractures osteosynthesis method, which consisted in applying the fixing appliances ensuring optimal limiting stress on the bone fragments for the given loads and the size of the peripheral fragment. According to the evaluation of the results of the effectiveness of treatment of the main group patients (Kalashnikov A .V., 1994)modification we have developed a differentiated approach and the scheme of rehabilitation treatment which allowed us to obtain good results after L-plate osteosynthesis in 87,5%, LCP plate - 81,8% and fixing screws - 71,4% in 12 months. This reduced the duration of the medical and social rehabilitation by a mean of 3-4 weeks compared with the control group.