Biomechanical analysis of suture anchors and suture materials used for toggle pin stabilization of hip joint luxation in dogs.
OBJECTIVE
To compare in vitro mechanical properties of toggle pins and toggle rods used as suture anchors and of 3 suture materials (50-lb monofilament polybutester, No. 5 braided polyester, and 5-mm woven polyester) commonly used as prosthetic ligaments in the repair of hip joint luxation in dogs.


METHODS
Femoropelvic specimens from the cadavers of 18 dogs.


METHODS
Suture anchors were compared by use of pullout tests. Suture materials were compared by use of monotonic and cyclic tensile tests; cyclic tensile tests were performed with the suture placed over the edge of an aluminum bar to simulate the edge of the femoral bone tunnel. In vitro mechanical properties of the ligament of the femoral head were determined by use of monotonic tensile tests, using bone-ligament-bone cadaveric specimens. The in vitro mechanical properties of the acetabulum-ligament-femur complex and of this complex following rupture of the ligament and stabilization with a toggle rod and 5-mm woven polyester were determined by use of compression tests that simulated weight-bearing.


RESULTS
Mechanical properties of the toggle rod were not significantly different from those of the toggle pin. Woven polyester had the longest fatigue life in cyclic testing. Hip joints stabilized with a toggle rod and woven polyester had less than half the strength in vitro of intact joints.


CONCLUSIONS
Results suggested that a toggle rod or toggle pin can be used for stabilization of hip joint luxations in dogs. Of the materials tested, braided polyester had the best in vitro mechanical properties.
Baltzer
W I
WI
Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis 95616, USA.
Schulz
K S
KS
Stover
S M
SM
Taylor
K T
KT
Kass
P H
PH
D000818:Animals; D001696:Biomechanical Phenomena; D001858:Bone Nails; D004283:Dog Diseases / Q000601:surgery*; D004285:Dogs; D006617:Hip Dislocation / Q000601:surgery / Q000662:veterinary*; D009757:Nylons / Q000737:chemistry; D011091:Polyesters / Q000737:chemistry / Q000592:standards; D011897:Random Allocation; D013537:Sutures / Q000592:standards*; D013718:Tensile Strength
D009757:Nylons; D011091:Polyesters