Fixation of periprosthetic femoral shaft fractures associated with cemented femoral stems: a biomechanical comparison of locked plating and conventional cable plates.
To determine which of 2 techniques for the treatment of periprosthetic femoral shaft fractures is of greater stiffness.


METHODS
A laboratory study using 8 pairs of matched, embalmed femurs.


METHODS
Femurs implanted with a cemented total hip prosthesis had a simulated periprosthetic femur fracture created distal to the implant. Fractures were fixed with a plate with locked screws or a plate with cables (Ogden construct). Fixation stability was compared in various loading modalities before and after cycling. Failure in torsional loading was then determined. The cement mantle was tested for crack propagation that may have occurred secondary to locked screw insertion and loading.


METHODS
Fixation stiffness (the ratio of applied load to displacement at the fracture site), torsional strength, mode of failure for each system, and cement mantle evaluation for cracks after screw insertion.


RESULTS
Locked plating was stiffer than the Ogden construct in pre- and post-cyclic axial loading and torsion. There was no difference in lateral bending stability or torsional failure loads.


CONCLUSIONS
Locked plating constructs were stiffer than the Ogden construct in axial loading and torsion. Although no differences in loads to failure during torsion were noted, locked plating constructs exhibited catastrophic failure not observed with the Ogden construct.
Fulkerson
Eric
E
Department of Orthopaedic Surgery, Hospital for Joint Diseases, New York, NY 10003, USA.
Koval
Kenneth
K
Preston
Charles F
CF
Iesaka
Kazuho
K
Kummer
Frederick J
FJ
Egol
Kenneth A
KA
D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects*; D001696:Biomechanical Phenomena; D001843:Bone Cements; D001860:Bone Plates; D002102:Cadaver; D005260:Female; D005264:Femoral Fractures / Q000209:etiology / Q000601:surgery*; D005592:Fracture Fixation / Q000295:instrumentation*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D010024:Osteoporosis / Q000150:complications; D011475:Prosthesis Failure
D001843:Bone Cements