Influence of Spinal Deformity Construct Design on Adjacent-Segment Biomechanics

Authors

Robert M. Koffie, Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA.
Bernardo de Andrada Pereira, Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA.Follow
Jennifer N. Lehrman, Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA.Follow
Jakub Godzik, Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA.
Anna G. Sawa, Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA.
Shashank V. Gandhi, Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA.Follow
Brian P. Kelly, Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA.Follow
Juan S. Uribe, Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA.
Jay D. Turner, Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA. Electronic address: Neuropub@barrowneuro.org.

Document Type

Article

Abstract

BACKGROUND: Adjacent level degeneration is a precursor to construct failure in adult spinal deformity surgery, but whether construct design affects adjacent level degeneration risk remains unclear. Here we present a biomechanical profile of common deformity correction constructs and assess adjacent level biomechanics. METHODS: Standard nondestructive flexibility tests (7.5 Nm) were performed on 21 cadaveric specimens: 14 pedicle subtraction osteotomies (PSOs) and 7 anterior column realignment (ACR) constructs. The ranges of motion (ROM) at the adjacent free level in flexion, extension, axial rotation, and lateral bending were measured and analyzed. RESULTS: ACR constructs had a lower ROM change on flexion at the proximal adjacent free level than constructs with PSO (1.02 vs. 1.32, normalized to the intact specimen, P < 0.01). Lateral lumbar interbody fusion adjacent to PSO and 4 rods limits ROM at the free level more effectively than transforaminal interbody fusion and 2 rods in correction constructs with PSO. Use of 2 screws to anchor the ACR interbody further decreased ROM at the proximal adjacent free level on flexion, but adding 4 rods in this setting added no further limitation to adjacent segment motion. CONCLUSIONS: ACR constructs have less ROM change at the adjacent level compared to PSO constructs. Among constructs with ACR, anchoring the ACR interbody with 2 screws reduces motion at the proximal adjacent free level. When PSOs are used, lateral lumbar interbody fusion adjacent to the PSO level has a greater reduction in adjacent-segment motion than transforaminal interbody fusion, suggesting that deformity construct configuration influences proximal adjacent-segment biomechanics.

Keywords

Adjacent level degeneration, Adult spinal deformity, Anterior column realignment, Lateral lumbar interbody fusion, Pedicle subtraction osteotomy, Proximal junctional kyphosis, Transforaminal lumbar interbody fusion

Medical Subject Headings

Adult; Biomechanical Phenomena; Cadaver; Humans; Lumbar Vertebrae (diagnostic imaging, surgery); Range of Motion, Articular; Rotation; Spinal Fusion

Publication Date

10-1-2022

Publication Title

World neurosurgery

E-ISSN

1878-8769

Volume

166

First Page

e656

Last Page

e663

PubMed ID

35872128

Digital Object Identifier (DOI)

10.1016/j.wneu.2022.07.076

Recommended Citation

Koffie, Robert M.; de Andrada Pereira, Bernardo; Lehrman, Jennifer N.; Godzik, Jakub; Sawa, Anna G.; Gandhi, Shashank V.; Kelly, Brian P.; Uribe, Juan S.; and Turner, Jay D., "Influence of Spinal Deformity Construct Design on Adjacent-Segment Biomechanics" (2022). Translational Neuroscience. 2261.
https://scholar.barrowneuro.org/neurobiology/2261