Fixation of periprosthetic femoral shaft fractures: a biomechanical comparison of two techniques.
OBJECTIVE
To determine which of two currently used techniques for the treatment of periprosthetic femoral shaft fractures provides the greater fixation rigidity and strength.


METHODS
A laboratory study using six matched pairs of femurs.


METHODS
Embalmed femur prosthesis constructs had a simulated periprosthetic fracture created and were fixed with a plate with proximal cables and distal bicortical screws (Ogden concept) or two allograft struts and cables. Fixation stability was compared in various loading modalities before and after cycling. They were then tested to failure.


METHODS
Fixation rigidity was defined as the ratio of applied load to the amount of displacement at the fracture.


RESULTS
In all loading modalities, the Ogden construct was more rigid than the allograft strut fixation. The Ogden construct required 1,295 newtons for failure and the allograft strut fixation required 950 newtons (p < 0.05).


CONCLUSIONS
The Ogden construct provided a more rigid and stronger initial fixation of a periprosthetic fracture than did the allograft construct.
Dennis
M G
MG
The Musculoskeletal Research Center, The Hospital for Joint Diseases Orthopaedic Institute, 301 East 17th Street, New York, NY 10003, U.S.A.
Simon
J A
JA
Kummer
F J
FJ
Koval
K J
KJ
Di Cesare
P E
PE
D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects / Q000379:methods; D001696:Biomechanical Phenomena; D002102:Cadaver; D005264:Femoral Fractures / Q000000981:diagnostic imaging / Q000209:etiology* / Q000601:surgery*; D005593:Fracture Fixation, Internal / Q000379:methods*; D006622:Hip Prosthesis / Q000009:adverse effects*; D006801:Humans; D008422:Materials Testing; D011336:Probability; D011474:Prosthesis Design; D011475:Prosthesis Failure; D011859:Radiography; D012680:Sensitivity and Specificity