Single cycle to failure in bending of three titanium polyaxial locking plates.
OBJECTIVE
Evaluation of the bending properties in one direction of three titanium polyaxial locking plate systems.


METHODS
The Polyaxial Advanced Locking System (PAX®) straight plate (PAX SP), the PAX®reconstruction plate (PAX RP), and the VetLOX reconstruction plates (VetLOX) were evaluated individually and as constructs applied to a bone model simulating a fracture gap and compared using a two-way analysis of variance and Tukey post-hoc analysis.


RESULTS
The PAX SP had the highest values of bending stiffness, bending structural stiffness and bending strength. When tested as plates alone, the PAX RP and VetLOX showed no differences with regard to bending stiffness and bending structural stiffness, whilst the PAX RP had significantly higher strength. The PAX RP construct had significantly higher bending stiffness, bending structural stiffness and bending strength than the VetLOX construct.


CONCLUSIONS
The PAX RP and VetLOX reconstruction plates are much more likely to fail when used as bridging implants, thus adjunct support is needed. The lower bending strength of the VetLOX reconstruction plates suggests it should not be used in fractures under high loads.
Dr. Chadi Eid, Ortovet stp srl, Piazza Alessandrini 2, Fidenza 43036, Italy, Phone: +39 320 064 7705, E-mail: chadi.eid@live.com or chadi.eid@ortovet.org.
Chadi
C
Eid
Filippo Maria
FM
Martini
Andrea
A
Bonardi
Filippo
F
Lusetti
Anna
A
Brandstetter de Belesini
Gianni
G
Nicoletto
D000818:Animals; D001696:Biomechanical Phenomena; D001860:Bone Plates / Q000592:standards / Q000662:veterinary*; D001863:Bone Screws; D005593:Fracture Fixation, Internal; D050723:Fractures, Bone / Q000601:surgery / Q000662:veterinary*; D008422:Materials Testing / Q000662:veterinary*; D008954:Models, Biological; D014025:Titanium
D014025:Titanium
Polyaxial; bone plate; four-point bending; locking plate; titanium