PURPOSE: Intraoperative @entity3330 is a well recognized intraoperative complication of @entity572 ( @entity572 ). This study was designed to establish an in-vitro model for @entity174 of the femur in cementless @entity572 and to assess the effect of @entity174 fixation by cerclage wiring using steel wire (Protasul). METHODS: Ten @entity1 femur specimens were studied. Longitudinal cracks were created by pressing a well fixed conical stem deeper into the femur in a material testing machine. RESULTS: The force necessary to propagate a @entity42747 in the femur was 1915 N to 9288 N (median 6531 N). This forces are according to 3 to 15 times (median 11 times) body weight. There was no difference of force between left and right femurs from the same individual (U-test). The femoral cortex fractured in 5 cases ventrally, in 6 cases medially and in 1 case laterally. After monofile cerclage wire application the force required to press prosthesis 5 mm deeper into the medullary canal was 0.3 to 2.7 times body weight. After monofile cerclage wire application pressing in the prosthesis 30 mm needed 1.8 to 8.1 times body weight. CONCLUSIONS: During insertion of a conical stem the orthopaedic surgeon should look for @entity174 of the medial cortex of the femur which is the most frequent location for @entity174 . This in-vitro model provides a reproductable method for the initiation and propagation of @entity3330 in press-fit noncemented @entity572 system and to assess the effect of @entity174 fixation in the form of cerclage wiring.

[An in vitro model for producing XXXX and for the study of primary stability of cerclage].

@entity1 :: ('9606', 'Species') :: ['human'] @entity174 :: ('MESH:D050723', 'Disease') :: ['fractures', 'initiation of fractures', 'fracture'] @entity42747 :: ('MESH:D003387', 'Disease') :: ['longitudinal crack'] @entity572 :: ('MESH:D006617', 'Disease') :: ['THA', 'cementless total hip arthroplasty'] @entity3330 :: ('MESH:D005264', 'Disease') :: ['femoral fracture', 'longitudinal femoral fractures']
@entity3330 :: (MESH:D005264,Disease) :: ['femoral fractures']
