Biomechanic conception of implant choice for primary total hip replacement in osteoporotic femur neck fractures is presented. Criterion for the choice is a localization of load-bearing surface of dense structure in acetabulum roof zone, i.e. sursile. Absolute indications to total hip replacement, use of bipolar and unipolar hemiprostheses are determined depending on the direction and deviation degree of sursile from horizontal axis of pelvis. Based on suggested conception the retrospective analysis of joint replacement results in 58 patients has been performed. The causes of protrusion and loosing of implants were studied.

Analysis of treatment of 526 patients with proximal femur fractures (362 patients with femoral neck fractures and 164 patients with trochanteric zone fractures) was performed. Patients' age ranged from 34 to 92 (mean 67). Algorithm of differentiated choice of operative tactics depending on fracture characteristics and injury term was presented. Low invasive osteosynthesis of femoral neck with bundle of stressed V-shaped pins was suggested. Theoretical and practical ground of that technique was given. Stress within fixative-bone system created after osteosynthesis by V-shaped pins, provided stable fixation even in marked osteoporosis. The importance of bone mineral density evaluation for the choice of treatment tactics as well as the necessity of medicamental correction of the disturbed bone remodeling after surgical treatment was noted.

Fracture of the femoral neck is a common injury of the human skeleton. High rate of postoperative complications induces to the search of optimum osteosynthesis technique. Treatment results for 259 patients (182 females, 77 males, mean age 72 years) with femoral neck fractures were analyzed. In study group (n=114) a dynamic derotation osteosyntesis and in control group (n=145) - DHS, a bundle of V-shaped curved pins, cannulated screws were used. Mathematic modelling of bone-implant system in different variants of derotation fixator screws position under load was performed. Use of dynamic derotation constructions in Garden 1 and Garden 2 femoral neck fractures ensured a consolidation of fractures in all clinical observations, in Garden 3 fractures - in 46.4%. Early dosage weight bearing not exceeding 60% of the body weight did not result in either fragments displacement or raise of the rate of femoral head avascular necrosis development. In patients under 60 years it is preferably to use dynamic derotation constructions with 4 screws placed in the femoral neck.