Methods: Ten lumbar spines from body donors were examined. Bisegmental dorsal spinal lumbar interbody fusion of the L3–L5 segments was performed using a pedicle screw–rod system (ROCCIA Multi-LIF Cage; Silony Medical, Germany). In group 1, the titanium rod was inserted without tension, whereas in group 2, the rod was attached to the pedicle screws at the L4 and L5 levels, creating a 5-mm gap. To attach the rod, the RP was used to press the rod into the pedicle screw. The rod was left in place for 30 minutes and then removed. Results: The rod reduction technique significantly increased the mechanical load on the overall construct measured by strain gauges (p<0.05) and resulted in outright implant failure with pedicle screw pullout in 88.9%. Conclusions In cases where the spondylodesis material is not fully attached within the pedicle screw, an RP can be used with extreme caution, particularly in osteoporotic bones, to avoid pedicle screw avulsion and screw anchor failure.

Methods: Ten lumbar spines from body donors were examined. Bisegmental dorsal spinal lumbar interbody fusion of the L3–L5 segments was performed using a pedicle screw–rod system (ROCCIA Multi-LIF Cage; Silony Medical, Germany). In group 1, the titanium rod was inserted without tension, whereas in group 2, the rod was attached to the pedicle screws at the L4 and L5 levels, creating a 5-mm gap. To attach the rod, the RP was used to press the rod into the pedicle screw. The rod was left in place for 30 minutes and then removed. Results: The rod reduction technique significantly increased the mechanical load on the overall construct measured by strain gauges (p<0.05) and resulted in outright implant failure with pedicle screw pullout in 88.9%. Conclusions In cases where the spondylodesis material is not fully attached within the pedicle screw, an RP can be used with extreme caution, particularly in osteoporotic bones, to avoid pedicle screw avulsion and screw anchor failure.

Methods: Ten lumbar spines from body donors were examined. Bisegmental dorsal spinal lumbar interbody fusion of the L3–L5 segments was performed using a pedicle screw–rod system (ROCCIA Multi-LIF Cage; Silony Medical, Germany). In group 1, the titanium rod was inserted without tension, whereas in group 2, the rod was attached to the pedicle screws at the L4 and L5 levels, creating a 5-mm gap. To attach the rod, the RP was used to press the rod into the pedicle screw. The rod was left in place for 30 minutes and then removed. Results: The rod reduction technique significantly increased the mechanical load on the overall construct measured by strain gauges (p<0.05) and resulted in outright implant failure with pedicle screw pullout in 88.9%. Conclusions In cases where the spondylodesis material is not fully attached within the pedicle screw, an RP can be used with extreme caution, particularly in osteoporotic bones, to avoid pedicle screw avulsion and screw anchor failure.

Methods: Ten lumbar spines from body donors were examined. Bisegmental dorsal spinal lumbar interbody fusion of the L3–L5 segments was performed using a pedicle screw–rod system (ROCCIA Multi-LIF Cage; Silony Medical, Germany). In group 1, the titanium rod was inserted without tension, whereas in group 2, the rod was attached to the pedicle screws at the L4 and L5 levels, creating a 5-mm gap. To attach the rod, the RP was used to press the rod into the pedicle screw. The rod was left in place for 30 minutes and then removed. Results: The rod reduction technique significantly increased the mechanical load on the overall construct measured by strain gauges (p<0.05) and resulted in outright implant failure with pedicle screw pullout in 88.9%. Conclusions In cases where the spondylodesis material is not fully attached within the pedicle screw, an RP can be used with extreme caution, particularly in osteoporotic bones, to avoid pedicle screw avulsion and screw anchor failure.