Atlanta-based Emory University School of Medicine researchers analyzed the impact of cage angle and surgical technique on segmental lordosis. Rojeh Melikian, MD, of DISC Sports & Spine in Marina Del Rey, Calif., and his team wanted to see the degree of sagittal plane correction achievable using the lateral transpsoas approach.
The study involved 13 lumbar motion segments between L1 and L5, which were dissected into single motion segments. The researchers measured segmental angles and disc heights under 50N and 500 N compressive loads under certain conditions.
Spine published the study.
Here are six insights:
1. The study found parallel or 10 degree cages did not increase segmental lordosis, compared with intact discs. Additionally, those cages achieved small lordosis compared with the collapsed disc condition.
2. The 30 degree cage placement with ALL release increased segmental lordosis by 10.5 degrees.
3. The addition of spinous resection increased segmental lordosis by 12.4 degrees.
4. Researchers found facetectomy and compression with pedicle screws increased lordosis to about 26 degrees.
5. None of the cages resulted in a decree in anterior or posterior disc height.
6. In conclusion, to achieve significant sagittal plane correction, the addition of spinous resection and facetectomy is needed.