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A biomechanical comparison between cortical bone trajectory fixation and pedicle screw fixation.

Oshino H, Sakakibara T, Inaba T, Yoshikawa T, Kato T, Kasai Y - J Orthop Surg Res (2015)

Bottom Line: There have been several reports on the pullout strength of cortical bone trajectory (CBT) screws, but only one study has reviewed the stability of functional spine units using the CBT method.The angular displacement from the time of no load to the time of maximum torque was defined as range of motion (ROM), and then, the mean ROM in the bend and rotation tests and the mean rate of relative change of ROM in both the bend and rotation tests were compared between the CBT and PS groups.There were no significant differences between the CBT and PS groups with regard to the mean ROMs and the mean rate of relative change of ROMs in both the bend and rotation tests.

View Article: PubMed Central - PubMed

Affiliation: Department of Mechanical Engineering, Mie University, Tsu City, Mie, Japan.

ABSTRACT

Purpose: There have been several reports on the pullout strength of cortical bone trajectory (CBT) screws, but only one study has reviewed the stability of functional spine units using the CBT method. The purpose of this study was to compare vertebral stability after CBT fixation with that after pedicle screw (PS) fixation.

Methods: In this study, 20 lumbar spine (L5-6) specimens were assigned to two groups: the CBT model group that underwent CBT screw fixation (n = 10) and the PS model group that underwent pedicle screw fixation (n = 10). Using a six-axis material testing machine, bend and rotation tests were conducted on each model. The angular displacement from the time of no load to the time of maximum torque was defined as range of motion (ROM), and then, the mean ROM in the bend and rotation tests and the mean rate of relative change of ROM in both the bend and rotation tests were compared between the CBT and PS groups.

Results: There were no significant differences between the CBT and PS groups with regard to the mean ROMs and the mean rate of relative change of ROMs in both the bend and rotation tests.

Conclusion: Intervertebral stability after CBT fixation was similar to that after PS fixation.

No MeSH data available.


Related in: MedlinePlus

Six-axis material test machine developed in our laboratory
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Fig4: Six-axis material test machine developed in our laboratory

Mentions: For the test, a six-axis material testing machine [8–10] developed in our laboratory (Fig. 4) was used. This testing machine adopts a parallel mechanism. A set of two actuators are located parallel at 120° to the object, and each of the six actuators is independently controlled. At the hand side, a six-axis kinesthetic sensor is equipped to detect the force in the x-, y-, and z-axes and the torque around each axis. Furthermore, this kinesthetic sensor enables force control by feeding back the detected values to the control system and enables motion with any degree of freedom.Fig. 4


A biomechanical comparison between cortical bone trajectory fixation and pedicle screw fixation.

Oshino H, Sakakibara T, Inaba T, Yoshikawa T, Kato T, Kasai Y - J Orthop Surg Res (2015)

Six-axis material test machine developed in our laboratory
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4537537&req=5

Fig4: Six-axis material test machine developed in our laboratory
Mentions: For the test, a six-axis material testing machine [8–10] developed in our laboratory (Fig. 4) was used. This testing machine adopts a parallel mechanism. A set of two actuators are located parallel at 120° to the object, and each of the six actuators is independently controlled. At the hand side, a six-axis kinesthetic sensor is equipped to detect the force in the x-, y-, and z-axes and the torque around each axis. Furthermore, this kinesthetic sensor enables force control by feeding back the detected values to the control system and enables motion with any degree of freedom.Fig. 4

Bottom Line: There have been several reports on the pullout strength of cortical bone trajectory (CBT) screws, but only one study has reviewed the stability of functional spine units using the CBT method.The angular displacement from the time of no load to the time of maximum torque was defined as range of motion (ROM), and then, the mean ROM in the bend and rotation tests and the mean rate of relative change of ROM in both the bend and rotation tests were compared between the CBT and PS groups.There were no significant differences between the CBT and PS groups with regard to the mean ROMs and the mean rate of relative change of ROMs in both the bend and rotation tests.

View Article: PubMed Central - PubMed

Affiliation: Department of Mechanical Engineering, Mie University, Tsu City, Mie, Japan.

ABSTRACT

Purpose: There have been several reports on the pullout strength of cortical bone trajectory (CBT) screws, but only one study has reviewed the stability of functional spine units using the CBT method. The purpose of this study was to compare vertebral stability after CBT fixation with that after pedicle screw (PS) fixation.

Methods: In this study, 20 lumbar spine (L5-6) specimens were assigned to two groups: the CBT model group that underwent CBT screw fixation (n = 10) and the PS model group that underwent pedicle screw fixation (n = 10). Using a six-axis material testing machine, bend and rotation tests were conducted on each model. The angular displacement from the time of no load to the time of maximum torque was defined as range of motion (ROM), and then, the mean ROM in the bend and rotation tests and the mean rate of relative change of ROM in both the bend and rotation tests were compared between the CBT and PS groups.

Results: There were no significant differences between the CBT and PS groups with regard to the mean ROMs and the mean rate of relative change of ROMs in both the bend and rotation tests.

Conclusion: Intervertebral stability after CBT fixation was similar to that after PS fixation.

No MeSH data available.


Related in: MedlinePlus