Related Experiment Video
Updated: Jul 3, 2026
07:25
Ovine Lumbar Intervertebral Disc Degeneration Model Utilizing a Lateral Retroperitoneal Drill Bit Injury
Published on: May 25, 2017
11.7K
Bionate Lumbar Disc Nucleus Prosthesis: Biomechanical Studies in Cadaveric Human Spines
Amparo Vanaclocha1, Vicente Vanaclocha2, Carlos M Atienza1
1Biomechanical Engineer, Biomechanics Institute of Valencia, Valencia 46022, Spain.
ACS Omega
|December 26, 2022
Summary
Spine nucleus replacement moderately increased disc mobility in cadaveric spines, with implants showing low expulsion and subsidence risks despite some operative damage. Customized implants are recommended.
Area of Science:
- Spine Biomechanics
- Orthopedic Surgery
- Biomaterials Science
Background:
- Degenerative disc disease is a common cause of low back pain.
- Nucleus replacement aims to restore spinal biomechanics and alleviate pain.
- Understanding the biomechanical performance of nucleus replacement devices is crucial.
Purpose of the Study:
- To determine the biomechanical performance of the Bionate 80A nucleus replacement device in cadaveric spines.
- To compare the biomechanics of customized versus overdimensioned implants.
- To assess the effects of nucleus replacement on spinal mobility and implant stability.
Main Methods:
- Cadaveric spines (L3-L4, L4-L5, L5-S1) underwent nucleotomy and nucleus implantation with either customized or overdimensioned Bionate 80A devices.
- Spinal motion (flexion, extension, lateral bending, torsion) was measured under increasing loads (2-8 Nm) using stereophotogrammetry.
- Expulsion tests (cyclic compression 50-550 N for 50,000 cycles) and subsidence tests (up to 6000 N compression) were performed.
Main Results:
- Nucleotomy increased disc mobility, particularly in lateral bending and torsion, with varying effects on adjacent segments.
- Nucleus implantation reduced mobility compared to nucleotomy but did not restore intact levels; overdimensioned implants showed similar or greater mobility than customized ones.
- No implant extrusion occurred up to 1068 N; anatomical structures collapsed first. No subsidence or fractures were observed up to 6812.3 N.
Conclusions:
- Nucleus implantation in nucleotomized cadaveric spines resulted in moderate mobility increases compared to intact spines, partly due to surgical damage.
- The Bionate 80A implant demonstrated low risks of expulsion and subsidence.
- Customized implants may offer better biomechanical profiles than overdimensioned ones.
Related Concept Videos
01:29Herniated Intervertebral Disc l: Introduction
Intervertebral disc herniation refers to the displacement of the nucleus pulposus (the gel-like inner core of the disc) through a tear or weakened area in the annulus fibrosus (the outer fibrous ring). The displaced disc material extends beyond the normal boundaries of the disc space and may compress or irritate nearby spinal nerve roots or, less commonly, the spinal cord.Etiology and Risk FactorsHerniation commonly results from degeneration, in which aging reduces disc hydration and...
01:27Degenerative Disc Disease I: Introduction
Degenerative disc disease is a chronic condition in which intervertebral discs gradually lose structure and function. It is not infectious or autoimmune; rather, it results from age-related biochemical and mechanical changes, influenced by genetic, metabolic, and environmental factors.Structure and Function of DiscsThe spine contains 23 intervertebral discs that absorb load, distribute forces, maintain spacing, and allow flexibility. Each disc consists of a nucleus pulposus, a gel-like core...
01:23Degenerative Disc Disease ll: Pathophysiology
The symptoms of degenerative disc disease arise from a combination of mechanical compression, vascular compromise, and biochemical inflammation, which together disrupt nerve function and produce pain.Mechanical CompressionDisc degeneration reduces height and elasticity, predisposing to herniation of the nucleus pulposus, a major cause of radicular pain. Herniations may be protrusion (bulging with intact annulus), extrusion (nucleus extends beyond disc but remains connected), or sequestration...