New Bone Formation in Axial Spondyloarthritis: A Review

 

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Abstract

Background

Axial spondyloarthritis (axSpA) is a chronic inflammatory disease primarily affecting the sacroiliac joints (SIJs) and the spine. Imaging plays a crucial role in the diagnosis of axSpA, with magnetic resonance imaging (MRI) and radiography being the primary modalities used in clinical practice. New bone formation occurs in both the spine (non-bridging and bridging syndesmophytes, transdiscal ankylosis, and ankylosis of small joints and posterior elements) and the SIJs (backfill and ankylosis). New bone formation indicates advanced axSpA.

Method

This review explores the role of imaging in the diagnosis and monitoring of axSpA, focusing on the significance of new bone formation, and provides an overview of the characteristic imaging findings of new bone formation in axSpA in each imaging modality.

Conclusion

Imaging methods, such as X-ray, MRI, and CT, have different diagnostic accuracies for detecting structural lesions and new bone formation. Each modality has its strengths and weaknesses, and the choice depends on the specific clinical context. Imaging is crucial for the diagnosis and monitoring of axSpA, particularly for the detection of new bone formation. Different imaging techniques provide valuable information about disease progression and treatment response. Understanding the significance of new bone formation and its detection using imaging modalities is essential for the accurate diagnosis and effective management of patients with axSpA.

Key Points

• New bone formation is a hallmark feature of advanced axial spondyloarthritis.

• New bone formation occurs both in the spine and in the sacroiliac joints.

• Differentiation of new bone formation in axial spondyloarthritis from that in other conditions such as diffuse idiopathic skeletal hyperostosis and from osteophytes is essential.

• Imaging methods, such as X-ray, MRI, and CT, have different diagnostic accuracies for detecting new bone formation.

Citation Format

• Ulas S, Deppe D, Ziegeler K et al. New Bone Formation in Axial Spondyloarthritis: A Review. Fortschr Röntgenstr 2024; 196: 550 – 559

Zusammenfassung

Hintergrund

Die axiale Spondyloarthritis (axSpA) ist eine chronisch entzündliche Erkrankung, die vor allem das Sakroiliakalgelenk (SIG) und die Wirbelsäule betrifft. Die Bildgebung spielt bei der Diagnose der axSpA eine entscheidende Rolle, wobei MRT und Röntgenuntersuchung die wichtigsten Untersuchungsmethoden in der klinischen Praxis sind. Knochenneubildung tritt sowohl an der Wirbelsäule (nicht brückenbildende und brückenbildende Syndesmophyten, transdiskale Ankylose und Ankylose der kleinen Gelenke und der hinteren Elemente) als auch am Sakroiliakalgelenk (Backfill und Ankylose) auf. Das Vorhandensein von Knochenneubildung weist auf fortgeschrittene Stadien der axSpA hin.

Methode

In dieser Übersichtsarbeit wird die Rolle der Bildgebung bei der Diagnose und Überwachung der axSpA untersucht, wobei der Schwerpunkt auf der Bedeutung der Knochenneubildung liegt, und es wird ein Überblick über die charakteristischen Bildgebungsbefunde der Knochenneubildung bei axSpA in den jeweiligen Bildgebungsmodalitäten gegeben.

Schlussfolgerung

Bildgebende Verfahren wie Röntgen, MRT und CT haben unterschiedliche diagnostische Genauigkeiten bei der Erkennung struktureller Läsionen und Knochenneubildung. Jede Modalität hat ihre Stärken und Schwächen, und die Wahl hängt vom jeweiligen klinischen Kontext ab. Die Bildgebung ist für die Diagnose und Überwachung der axSpA von entscheidender Bedeutung, insbesondere für den Nachweis von Knochenneubildung. Verschiedene bildgebende Verfahren liefern wertvolle Informationen über das Fortschreiten der Krankheit und das Ansprechen auf die Behandlung. Das Verständnis der Bedeutung der Knochenneubildung und ihrer Erkennung durch bildgebende Verfahren ist für eine genaue Diagnose und eine wirksame Behandlung der axSpA unerlässlich.

Kernaussagen

• Knochenneubildung ist kennzeichnende Veränderung bei meist fortgeschrittener axialer Spondyloarthritis.

• Knochenneubildung kommt sowohl an der Wirbelsäule als auch am Sakroiliakalgelenk vor.

• Die Unterscheidung zwischen Knochenneubildung bei axialer Spondyloarthritis und anderen Differenzialdiagnosen, wie der diffusen idiopathischen skeletalen Hyperostosis, sowie degenerativ bedingten Spondylophyten ist essenziell.

• Bildgebende Verfahren wie Röntgen, MRT und CT haben unterschiedliche diagnostische Genauigkeiten bei der Darstellung von Knochenneubildung.

Publication History

Received: 27 June 2023

Accepted: 06 September 2023

Article published online:
09 November 2023

© 2023. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commecial purposes, or adapted, remixed, transformed or built upon. (https://creativecommons.org/licenses/by-nc-nd/4.0/)

Georg Thieme Verlag KG
Rüdigerstraße 14, 70469 Stuttgart, Germany

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