Subchondral bone strength of the sacroiliac joint-a combined approach using computed tomography osteoabsorptiometry (CT-OAM) imaging and biomechanical validation. (November 2020)

• Record Type: Journal Article
• Authors: Poilliot, Amélie; Li, Kai Chun; Müller-Gerbl, Magdalena; Toranelli, Mireille; Zhang, Ming; Zwirner, Johann; Hammer, Niels
• Is Part Of: Journal of the mechanical behavior of biomedical materials. Volume 111(2020)
• Publication Date: 2020-11
• Subjects: Bone mineral density -- Computed tomography osteoabsorptiometry -- Housfield units -- Mechanical testing -- Sacroiliac joint -- Subchondral bone plate; Biomedical materials -- Periodicals; Biomedical materials -- Mechanical properties -- Periodicals; Biomedical materials; Biomedical materials -- Mechanical properties; Periodicals; Electronic journals; 610.28
• DOI: 10.1016/j.jmbbm.2020.103978
• Languages: English
• ISSNs: 1751-6161

Abstract

Abstract: Bone mineral density distribution patterns at the sacroiliac joint (SIJ) may reflect long-term adaptation patterns to the loading the joint endures. This study aims to display bone mineralisation patterns of the articular SIJ subchondral lamella using computed tomography (CT) osteoabsorptiometry and mechanical indenting, to determine whether a relationship exists between mineralisation and mechanical strength. Twenty hemipelves were CT-scanned before osteoabsorptiometry densitograms were derived. Each articular side of eleven SIJs was mechanically indented following a 10-mm grid scheme. The sacral surface displayed lower Hounsfield unit (HU) values (≤ 700 HU) than the iliac side (> 700 HU). The apex, superior corner and borders yielded the highest HU scores (> 700 HU). Penetration strength was significantly higher on the iliac side ( p < 0.04). Mineral density correlated positively with penetration strength of the subchondral bone layer ( p < 0.05). No correlations were found between the HU values, nor between penetration strength of corresponding sides of the same SIJ in the majority of cases ( p > 0.05). The iliac subchondral lamella is mechanically denser than the sacral aspect. The non-correlation between density and bone strength of articulating sides indicates biomechanical non-conformity. Loading throughout the SIJ may follow a complex distribution pattern involving the surrounding soft tissues, suspending the sacrum between the ilia. Graphical abstract: Image 1 Highlights: The iliac subchondral lamella is mechanically denser than the sacral side. Bone density and bone strength of articulating sides do not correlate, indicating biomechanical incongruence. CT-OAM reflects the biomechanical properties of the sacroiliac auricular subchondral lamella obtained from indentation tests.