Absorbable self-reinforced polyglycolide (SR-PGA) screws for the fixation of fractures and osteotomies: strength and strength retention in vitro and in vivo.
The initial mechanical strength and strength retention in vitro and in vivo of novel absorbable and self-reinforced polyglycolide (SR-PGA) screws for the fixation of fractures and osteotomies were determined. The SR-PGA screws showed initial bending strength values comparable with those of yield strength of standard stainless steel. The SR-PGA screws lost all their bending and shear strengths in 6 weeks in vivo. The strength retention properties of SR-PGA screws are sufficient for safe fixation of relatively rapidly consolidating fractures and osteotomies of cancellous bone that are not exposed to hard mechanical stresses.
Vasenius
J
J
Department of Orthopaedics and Traumatology, University Central Hospital, Helsinki, Finland.
Helevirta
P
P
Kuisma
H
H
Rokkanen
P
P
Törmälä
P
P
D000818:Animals; D001863:Bone Screws / Q000592:standards*; D005592:Fracture Fixation / Q000295:instrumentation*; D008422:Materials Testing; D010027:Osteotomy / Q000295:instrumentation*; D011100:Polyglycolic Acid; D011817:Rabbits; D013718:Tensile Strength; D013997:Time Factors