CT Osteoabsorptiometry Assessment of Subchondral Bone Density Predicts Intervertebral Implant Subsidence in a Human ACDF Cadaver Model. Issue 5 (June 2023)

• Record Type: Journal Article
• Authors: Orías, Alejandro A. Espinoza; Sheha, Evan; Zavras, Athan; John, Paul; Fitch, Ashlyn A.; An, Howard S.; Inoue, Nozomu; Colman, Matthew
• Is Part Of: Global spine journal. Volume 13:Issue 5(2023)
• Page Start: 1374
• Page End: 1383
• Publication Date: 2023-06
• Subjects: subchondral bone mineral density -- computed tomography osteoabsorbptiometry -- cervical spine -- subsidence -- endplate -- degenerative -- intervertebral disc -- vertebrae -- cartilage -- bone; Spine -- Diseases -- Periodicals; Spine -- Diseases -- Treatment -- Periodicals; Spine -- Abnormalities -- Periodicals; Spine -- Surgery -- Periodicals; 616.73
• DOI: 10.1177/21925682211034845
• Languages: English
• ISSNs: 2192-5682

Abstract

Study Design: Cadaveric biomechanics study. Objective: Subchondral bone mineral density (sBMD) reflects the long-term mineralization and distribution of stress on joints. The use of 3-dimensional (3-D) methods to evaluate sBMD, including computed tomography osteoabsorptiometry (CT-OAM), enables the assessment of density distribution with emphasis on subchondral bone. This study sought to measure the sBMD of cervical endplates using CT-OAM and correlate it to mechanical implant subsidence in a cadaveric model. Methods: Fourteen fresh human cadaveric cervical spines were subjected to dynamic testing after single level discectomy and instrumentation using a PEEK interbody spacer. Specimens were imaged with CT 3 times: 1st) whole intact cervical spine, 2nd) after implantation, and 3 rd) after testing. These images were used to assess sBMD distributions using CT-OAM directly underneath the spacer. Subsidence was defined as the displacement of the device into the endplates. Results: The observed "failure mode" was consistently recorded as subsidence, with a mean of 0.45 ± 0.36 mm and 0.40 ± 0.18 mm for the C4-5 and C6-7 levels, respectively. There were no differences by level. The experimental cyclic test showed that denser endplates experienced less deformation under the same load. Conclusions: This study achieved its stated aim of validating the use of CT-OAM as a method to analyze the sBMD of the cervical endplates. Studies such as this are providing new information on available technology such as CT-OAM, providing new tools for clinicians treating spinal conditions in need of augmentation and stabilization via interbody devices.