Vet Comp Orthop Traumatol 2012; 25(01): 36-41
DOI: 10.3415/VCOT-11-03-0045
Original Research
Schattauer GmbH

In vitro biomechanical comparison of three methods for internal fixation of femoral neck fractures in dogs

S. C. Fisher
1   Department of Clinical Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi, USA
,
R. M. McLaughlin
1   Department of Clinical Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi, USA
,
S. H. Elder
2   Department of Agricultural and Biological Engineering, Mississippi State University, Mississippi, USA
› Author Affiliations
Further Information

Publication History

Received: 22 March 2011

Accepted: 27 July 2011

Publication Date:
18 December 2017 (online)

Summary

The in vitro biomechanical properties of three methods for internal fixation of femoral neck fractures were evaluated. Fifty cadaveric femora from Beagle dogs were used. Ten intact femora served as controls. In 40 femora, an osteotomy of the femoral neck was performed to simulate a transverse fracture. With the remaining 30 femora, three repair methods (two medium Orthofix pins, a 2.7 mm cortical bone screw placed in lag fashion and an anti-rotational Kirschner wire, or three divergent 1.1 mm Kirschner wires) were used to stabilize the osteotomies, and 10 osteotomies were stabilised per repair method. These 30 femora where then subject to monotonic loading to failure. Construct stiffness and load to failure were measured. In the remaining 10 femora, pressure sensitive film was placed at the osteotomy site prior to stabilization with either two Orthofix pins (n = 5) or a screw placed in lag fashion (n = 5) to determine the compressive pressure (MPa), compressive force (KN) and area of compression (cm2).

There was no significant difference in the stiffness or load to failure for the three repair methods evaluated. There was no significant difference in the compressive pressure, compressive force or area of compression in osteotomies stabilized with Orthofix pins and 2.7 mm bone screws.

 
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