Biomechanical evaluation of a biomimetic spinal construct

Area of Science:

• Biomechanical Engineering
• Spinal Fusion Research
• Biomaterials Science

Background:

• Cadaveric and animal spine models present limitations including disease transmission, variability, and decay.
• Synthetic biomimetic spine models offer a potential alternative for in vitro biomechanical testing.
• Evaluating synthetic models is crucial for advancing spinal fusion research.

Purpose of the Study:

• To evaluate the biomechanical properties of a synthetic biomimetic spine model.
• To assess the mechanical performance of lateral plating in lateral interbody fusion.
• To compare the efficacy of lateral versus anterior lumbar interbody fusion constructs.

Main Methods:

• Three L3/4 synthetic spinal motion segments were subjected to 10,000 cycles of pure moment testing (flexion-extension, lateral bending, axial rotation).
• Testing included intact, lateral cage alone, lateral cage and plate, and anterior cage and plate conditions.
• Results were analyzed using ANOVA with post-hoc Tukey's HSD test.

Main Results:

• Range of motion showed logarithmic growth with cycling, with no significant changes after a 12-hour rest period.
• All tested parameters were comparable to reported cadaveric spine values.
• Lateral cage and plate constructs demonstrated no significant difference in range of motion compared to anterior cage and plate constructs.

Conclusions:

• The synthetic spine model exhibits anatomical and biomechanical similarities to the human lumbar spine, making it a viable alternative for in vitro testing.
• The model's stability and lack of biohazard allow for non-destructive, repeatable testing of spinal procedures and devices.
• Lateral lumbar interbody fusion with plating is biomechanically comparable to anterior lumbar interbody fusion with plating.