Costovertebral joint involvement in patients with axial spondyloarthritis

Distribution of spinal damage in patients with axial spondyloarthritis as assessed by MRI: a prospective and blinded study

BACKGROUND

Axial spondyloarthritis (SpA) leads to structural bone lesions in every part of the vertebral column. These lesions are only partially visualized on conventional radiographs, omitting posterior parts of the vertebral column and the thoracic spine, that may nevertheless contribute to impaired spinal mobility and function in patients with axial SpA.

METHODS

In this prospective and blinded investigation, we assessed the distribution of structural spinal lesions using magnetic resonance imaging (MRI) of the whole spine in 55 patients with axial SpA classified according to the Assessment in Spondyloarthritis International Society (ASAS) criteria. After assessment of spinal mobility and function two blinded radiologists independently evaluated MRIs of 23 vertebral units in every patient. Non-parametric statistical methods, Spearman's correlation and linear regression models were used to analyze structural lesion distribution and the relationship with clinical spinal mobility and function parameters.

RESULTS

In 55 patients with axial SpA (13 females, average disease duration 14.9 years) 657 ventral and 139 dorsal vertebral body structural bone lesions and, notably, 534 facet joint lesions could be visualized. The median number of lesions per patient was higher in the thoracic (8.5, range 1.0-41.0) than in the lumbar (7.5, range 0.0-27.5) and the cervical spine (3.5, range 0.0-24.5). A negative correlation was noted between the number of osteoproliferative structural bone lesions and impairment of spinal mobility and function in univariate, but not in multivariate analyses.

CONCLUSION

MRI of the whole spine revealed a high prevalence of lesions in dorsal parts of the vertebral column and in the thoracic spine in patients with axial SpA that may not be adequately visualized on conventional radiographs. These findings could further contribute to a better understanding of reduced mobility of the spine typically associated with axial SpA and assist diagnostics.

Advancements in Imaging Techniques for Early Diagnosis and Management of Axial Spondyloarthritis

PURPOSE OF REVIEW

We aimed to introduce recent finding of imaging studies used in axial spondyloarthritis (axSpA).

RECENT FINDINGS

Using low-dose whole spine CT (CT syndesmophyte score [CTSS]) improved diagnostic accuracy for evaluating spinal structural progression than previous method (modified Stoke Ankylosing Spondylitis Spinal Score [mSASSS]) in axSpA. The novel definition of positive finding of sacroiliac joint (SIJ) and spine magnetic resonance imaging (MRI) enabled to diagnose axSpA earlier than plain radiography. In addition, novel MRI protocol such as volumetric interpolated breath-hold examination improved detection rate of structural change of axial joints in axSpA, Nuclear medicine imaging showed potential for diagnosis and predicting progression of axSpA. Ultrasonography guided injection is useful for controlling local joint pain of axSpA. AxSpA is characterised by pain and inflammation of axial joints such as the SIJ and spine. Detection of active inflammatory lesions using MRI has expanded the subtypes of axSpA to include non-radiographic axSpA (nr-axSpA). In addition, many other imaging techniques have improved, and can now detect structural and early inflammatory lesions of the axial joints. In addition, a method for quantitative measurement of syndesmophytes by CTSS has been developed; this method is more accurate and sensitive than the mSASSS for detecting spinal structural damage. Here, we discuss the current knowledge and clinical advances in computed tomography, MRI, nuclear medicine imaging, and ultrasonography as imaging methods for axSpA.

Costotransverse joint ankylosis and their association with syndesmophyte progression in patients with radiographic axial spondyloarthritis

Background

Abnormal new bone formation can occur not only in the vertebral body but also can occur in facet, costovertebral, and costotransverse joints in radiographic axial spondyloarthritis (r-axSpA) patients. Little is known about the association between syndesmophyte progression and paravertebral joint ankylosis in r-axSpA.

Objectives

Costotransverse joint ankylosis in r-axSpA patients was measured. Furthermore, the association between syndesmophyte progression for 2 years assessed by computed tomography syndesmophyte score (CTSS) and facet, costovertebral, and costotransverse joints ankylosis were evaluated.

Design

Single-center, prospective, cohort study.

Methods

Whole spine CT images taken at baseline and 2-year follow-up were used to calculate the CTSS of the vertebral body. In addition, ankylosis of the facet/costovertebral/costotransverse joints was scored. CTSS (range, 0-552) and facet joint ankylosis (range, 0-46) were assessed at 23 vertebral units. Costovertebral joints at T1-T12 (range, 0-48) and costotransverse joints at T1-T10 (range, 0-20) were also assessed by independent two readers. Intraclass correlation coefficients (ICC) were calculated to determine inter-reader reliability. Odds ratios (OR) were calculated to identify the associations between syndesmophyte progression and the baseline status of facet, costovertebral, and costotransverse joints.

Results

In all, 50 patients with r-axSpA were included. Readers 1 and 2 identified C7-T3 (facet joints), T5-T7 and T12 (costovertebral joints), and T8-T9 (costotransverse joints), as common sites of ankylosis at baseline and at 2-year follow-up. The ICCs for the facet, costovertebral, and costotransverse joints at baseline were 0.876, 0.952, and 0.753, respectively. OR of baseline costovertebral and costotransverse joint ankylosis for predicting syndesmophyte progression of the vertebral body was 4.644 [95% confidence interval (CI), 2.295-9.398] and 1.524 (95% CI, 1.036-2.244), respectively.

Conclusion

Costotransverse joint ankylosis in r-axSpA patients can be measured semi-quantitatively on whole spine CT, and ankylosis of the costotransverse and costovertebral joints predicts the progression of syndesmophytes.Trial registration: Not applicable.

[Computed tomography versus magnetic resonance imaging : Pros and cons in axial spondyloarthritis]

The diagnosis of axial spondyloarthritis depends on direct visualization of the sacroiliitis in addition to clinical assessment and determination of the histocompatibility antigen HLA-B27. While the value of conventional radiographic images has meanwhile been described in many studies as insufficient to diagnose the disease at an early stage, magnetic resonance imaging and also computed tomography now offer the possibility to visualize findings, such as bone marrow edema, erosion, fat metaplasia, backfill and ankylosis. Thus, it is necessary to decide which procedure should be used and when. Furthermore, both cross-sectional imaging techniques are currently undergoing major changes, and technical advancements are making great strides every year. This article provides an overview of which future technologies will be included in the rheumatological diagnostics of the sacroiliac joints. This overview also illustrates which standard methods are established in the diagnostics of axial spondyloarthritis and how they are used.