The Biomechanical Initial Exploration Of Truss Type Structure Internal Fixation Apparatus In Internal Fixation Of The Intertrochanteric Femoral Fracture

With the increase of the aged people, the incidences of femoral intratrochanteric fracture in elder patients are high because of osteoprosis. The ideal results cannot be get by non-surgical treatment .Though more and more patients are fired by internal fixation and get effective treatment ,there are a lot of problems such as delayed union and malunion that need to be solved. It is necessary to study the biomechanical function of trabeculae of proximal femoral and to use new infernal fixation which are designed according to the structure of trabecular.To study the trabecular structure of proximal femus and evaluate the truss type structure internal fixation apparatus (TTH) which are use to fix intratrochanteric fracture, 25 carnival femus were used. First, proximal femus are scaned by CT from lesser trochanter to greater trochanter. Second ,intratrochanteric fractures were made and fixed by Gamma nails,AO plates and Richard nail and TTH respectively . Stress test were done to got the intensity of internal fixation and to observe the effect on fractures .The results indicate that the intensity of TTH is higher than AO plate and Richard nail (p<0.05) and is similar with Gamma nail .The masking of TTH is lower than Gamma nail. AO plate and Richard nail (p<0.05) .We observed that the trabecular of supporting band and tensive band mix together and intercross in the center of femoral head. The calcar is the trabecular extending from the anterior region of the lesser trochanter and radiating from the anterior region of the lesser trochanter and radiating to the posterosuperior region of the greater trochanter .The calcar mix with the tensive trabecular by the type of gradecrossing. The crossing points focus on the posterolateral region of the greater trochanter mostly. We can draw the conclusion that trabecuare of proximal femus is important to maintain the structure of proximal femus and TTH is an effective fixation for intertrochenteric fracture because it is designed according to the biomechanical structure of proximal femus .