Data from: Biomechanical evaluation of peak reverse torque (PRT) in a dynamic compression plate-screw construct used in a goat tibia segmental defect model

Background Peak reverse torque (PRT) is a valid method to evaluate
implants’ secondary stability in the healing bone. The secondary stability
is achieved by the implant over time and it has been positively correlated
with the implants’ osseointegration level. In other words, peak reverse
torque is the force required to break the bone-implant interface. The
purpose of this study was to compare the peak reverse torque for the
self-tapping and non-self-tapping screws used in a dynamic compression
plate–screw–bone construct after 60 days of loading when used to stabilize
2.5-cm defects in the tibia of goats. The second objective was to compare
the peak removal torque of the screws placed in the different positions to
evaluate the impact of construct biomechanics on implants
osseointegration. Results In total, 176 non-self-tapping screws and 66
self-tapping screws were used to fix the 8-holes dynamic compression
plates to the bones. The screws were placed in the tibiae from proximal
(position sites 1,2, 3) to distal (position sites 4,5,6) and were removed
60 days post-implantation. The animals remained weight-bearing throughout
the study period. The screws placed in the proximal diaphysis had
significantly less peak reverse torque than screws placed in the distal
diaphysis in both groups (p < 0.05). The peak reverse torque
resistance was also significantly less for the non-self-tapping screws as
compared with the self-tapping screws (p < 0.05). The intracortical
fractures in the trans-cortex occurred significantly more frequently
during the placement of non-self-tapping screws (p < 0.05) as
compared with self-tapping screws (p < 0.05). Conclusions Based on
these results, we concluded that self-tapping screws may be expected to
maintain a more stable bone-implant interface during the first 60 days of
loading as compared with non-self-tapping screws. This should be a
consideration for orthopedic surgeons and scientists using bone plates to
stabilize non-load sharing fractures when a stable plate-screw-bone
interface is needed to ensure prolonged stability.