Bt. Huss et al., EFFECTS OF TEMPERATURE AND STORAGE TIME ON PIN PULL-OUT TESTING IN HARVESTED CANINE FEMURS, American journal of veterinary research, 56(6), 1995, pp. 715-719
Effects of temperature and storage time on canine bone-transfixation p
in specimens were tested by comparing pin pull-out forces. A total of
16 femurs from 8 mature dogs were tested. Five nonthreaded Steinmann p
ins were placed through both cortices in the diaphysis of each femur.
The femurs were then sectioned tranversely between each pin, with a bo
ne-pin specimen placed evenly into each of 5 groups prior to biomechan
ical testing. Four bone-pin specimen groups were stored at -20 or -70
C for 14 or 28 days, while 1 specimen group was immediately tested. Pu
ll-out forces for frozen groups were compared with pull-out forces for
the fresh group. Using two-way ANOVA, there was no statistical differ
ence in mean axial-extraction forces among bone-pin specimens in any o
f the tested groups. It is concluded that acute pin pull-out forces ar
e not significantly affected by freezing temperature or time. However,
specimens stored at -20 C for as few as 14 days had a trend for incre
ased pull-out forces, compared with freshly harvested specimens. There
fore, the authors recommend storage of bone-pin specimens at -70 C whe
n possible.