Lumbar subtotal corpectomy non-fusion model produced using a novel prosthesis.

Area of Science:

• Spinal biomechanics
• Orthopedic surgery
• Biomaterials engineering

Background:

• Lumbar subtotal corpectomy often necessitates spinal reconstruction.
• Non-fusion techniques aim to preserve spinal segment mobility.
• Evaluating novel prostheses requires robust biomechanical models.

Purpose of the Study:

• To design and evaluate a movable artificial lumbar complex (MALC) prosthesis.
• To establish an in vitro model for assessing non-fusion lumbar reconstruction.
• To determine the biomechanical stability and segmental movement preservation of the MALC prosthesis.

Main Methods:

• A movable artificial lumbar complex (MALC) prosthesis was designed.
• An in vitro anterolateral lumbar corpectomy non-fusion model was established using 26 goat lumbar spine specimens.
• Biomechanical testing assessed range of motion (ROM) in flexion-extension, lateral bending, and axial rotation.

Main Results:

• The MALC prosthesis demonstrated comparable stability to intact spines in flexion, extension, lateral bending, and axial torsion.
• Non-fusion reconstruction with MALC significantly preserved L2-3 ROM while allowing controlled increases in L3-4 and L4-5 ROM.
• No significant difference in Bone Mineral Density (BMD) was observed among groups.

Conclusions:

• The MALC prosthesis offers immediate stability and preserves functional segment movement after lumbar subtotal corpectomy.
• The prosthesis effectively maintains mobility without abnormal adjacent segment hypermobility.
• Further in vivo and human specimen studies are recommended to validate findings.