Imaging of Sacroiliac Pain: The Current State-of-the-Art

Pain in the sacroiliac (SI) region is a common clinical manifestation, often caused by diseases involving the SI joints. This is typically due to inflammation or degenerative changes, while infections or cancer are less frequent causes. The SI joint is challenging to image accurately because of its distinct anatomical characteristics. For an accurate diagnosis, conventional radiography often needs to be supplemented with more precise methods such as magnetic resonance imaging (MRI) or computed tomography (CT). Sacroiliitis, a common presenting feature of axial spondyloarthritis (axial SpA), manifests as bone marrow edema, erosions, sclerosis, and joint space narrowing. Septic sacroiliitis and repetitive stress injuries in sports can also cause changes resembling inflammatory sacroiliitis. Other conditions, such as osteitis condensans ilii (OCI), can mimic the radiologic characteristics of sacroiliitis. Inflammatory lesions are diagnosed by concurrent erosions, hyperostosis, and ankylosis. Ligament ossifications or mechanical stress can also result in arthritic disorders. Determining the exact diagnosis can be aided by the distribution of the lesions. Inflammatory lesions can affect any part of the articulation, including the inferior and posterior portions. Mechanical lesions, such as those seen in OCI, often occur in the anterior middle region of the joint. In cases of idiopathic skeletal hyperostosis, ligament ossification is found at the joint borders. This pictorial essay describes common SI joint problems, illustrated with multimodal imaging data. We, also, discuss strategies for selecting the best imaging modalities, along with imaging pitfalls, key points, and approaches for treating patients with suspected inflammatory back pain.

A Good Response to Nonsteroidal Antiinflammatory Drugs Does Not Discriminate Patients With Longstanding Axial Spondyloarthritis From Controls With Chronic Back Pain

OBJECTIVE

To compare the response to nonsteroidal antiinflammatory drugs (NSAIDs) in patients with longstanding axial spondyloarthritis (axSpA) and controls with back pain (nonspondyloarthritis [non-SpA]).

METHODS

Consecutive outpatients with chronic back pain (axSpA or non-SpA), were prospectively recruited. Any previous NSAIDs were withdrawn 2 days before study start (baseline). Back pain was assessed using a numerical rating scale (NRS; range 0-10) starting at 2 hours after baseline and several times thereafter up to 4 weeks. "Any response" to NSAIDs was defined as improvement of back pain on the NRS > 2 units, and "good response" as improvement > 50%, compared to baseline.

RESULTS

Among 233 patients included, 68 had axSpA (29.2%) and 165 had non-SpA back pain (70.8%). The mean age was 42.7 (SD 10.7) vs 49.3 (SD 11.1) years, symptom duration 15.1 (SD 11.1) years vs 14.6 (SD 11.9) years, and pain score 5.9 (SD 2.3) vs 6.3 (SD 2.0), respectively. Overall, of patients with axSpA or non-SpA back pain, 30.9% vs 29.1% of patients showed any response and 23.5% vs 16.4% of patients showed a good response after 4 weeks, respectively (P value not significant). No differences were found in the rapidity of response or between subgroups of patients based on demographics, including different stages of axSpA.

CONCLUSION

No major differences in the response to NSAIDs were found between patients with axSpA and those with non-SpA with longstanding chronic back pain. The item in the Assessment of SpondyloArthritis international Society classification criteria on "response to NSAIDs" needs more study.

Advanced practice physiotherapists in Scottish primary care: Axial Spondyloarthropathy epidemiology, time to diagnosis, and referrals to rheumatology

OBJECTIVES

(1) Generate empirical knowledge of a Musculoskeletal (MSK) Advanced Practice Physiotherapist (APP) Service in Scottish Primary Care; (2) Identify the incidence and baseline time to diagnosis of Axial Spondyloarthropathy (AxSpA); (3) Identify APP Rheumatology referral fulfilment of the NICE 2017 Guidelines and Spondylarthritis Diagnosis Evaluation (SPADE) Tool; (4) Calculate APP Rheumatology referral conversion rates for AxSpA diagnosis and further investigation; (5) Contribute towards the current body of literature for informing analysis of MSK APP services within Scottish Primary Care.

METHODS

An audit and evaluation approach was undertaken over a 3-year period (May 2019-April 2022). Relevant clinical cases from the whole-service data-set were identified and analysed, using retrospective electronic healthcare record review and descriptive statistical techniques.

RESULTS

A total of 37,656 primary care MSK APP consultations took place, with N = 19 suspected AxSpA referrals made to Rheumatology. N = 6 cases of AxSpA were diagnosed by a Rheumatologist (31.6%). The mean age of individuals diagnosed with AxSpA was 39.6 ± 8.8, and 66.7% (4/6) were female. Mean time to diagnosis was 3.4 years, and incidence per-10,000 person-years was 1.6. Compliance of referrals with the NICE 2017 Guidelines and SPADE Tool Criteria was 78.9%. Of those diagnosed with AxSpA, 66.7% met both referral criterion sets.

CONCLUSION

Those referred by an MSK APP from primary care had a 5.1 year shorter time to diagnosis than the previous reported UK average of 8.5 years. APPs identified relevant AxSpA features in referring to Rheumatology, and supported effective implementation of the local secondary care pathway.

Prevalence of Inflammatory Back Pain in a Low-Income Population

BACKGROUND

Inflammatory back pain (IBP) is a major criterion in identifying axial spondyloarthritis. Whether socioeconomic issues impact prevalence of IBP assessed using standardized questionnaires has not been assessed. We determined IBP prevalence and performance of IBP questionnaires in a low-income, low-literacy population.

METHODS

Individuals were interviewed in Fortaleza, Brazil, for the prevalence of IBP using Calin's, Berlin, and ASAS IBP questionnaires; monthly family income (US dollars), literacy (>/≤8 school years [SYs]), and smoking habit (present/absent) were registered.

RESULTS

Two hundred nineteen individuals were included (mean age, 38.2 ± 12.9 years), 110 (50.2%) men, 58 (26.4%) White, and 38 (17.3%) smokers. Overall, 152 (69.4%) declared

CONCLUSIONS

This is the first report on IBP prevalence in a low-income, low-literacy population. Chronic back pain was highly prevalent with almost 15% having IBP using ASAS criteria. Inflammatory back pain prevalence looked similar using ASAS and Berlin criteria; values were higher using Calin's criteria. Literacy or income did not influence IBP prevalence in this population, which was higher among women. The higher prevalence of IBP using Calin's criteria in this population should be taken into account as it might impact studies aiming to determine prevalence of axial spondyloarthritis in clinical studies in this scenario.

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MESH Headings

• Adult
• Back Pain/epidemiology
• Brazil/epidemiology
• Female
• Humans
• Male
• Middle Aged
• Poverty
• Prevalence
• Spondylarthritis/epidemiology
• Surveys and Questionnaires

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Affiliation(s)

Jobson Lopes de Oliveira From the Department of Internal Medicine, Faculty of Medicine, Universidade Federal do Ceará, Fortaleza, Brazil
Guilherme Ferreira Maciel da Silva From the Department of Internal Medicine, Faculty of Medicine, Universidade Federal do Ceará, Fortaleza, Brazil
Igor Albuquerque Nogueira From the Department of Internal Medicine, Faculty of Medicine, Universidade Federal do Ceará, Fortaleza, Brazil
Artur Queirós Azevedo From the Department of Internal Medicine, Faculty of Medicine, Universidade Federal do Ceará, Fortaleza, Brazil
Xenofon Baraliakos Rheumazentrum Ruhrgebiet Herne, Ruhr-University Bochum, Bochum, Germany
Francisco Airton Castro Rocha From the Department of Internal Medicine, Faculty of Medicine, Universidade Federal do Ceará, Fortaleza, Brazil

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Inflammatory back pain: a concept, not a diagnosis

PURPOSE OF REVIEW

The concept of inflammatory back pain (IBP) describes a cohort of patients with chronic back pain (CBP) who have distinct clinical characteristics, rather than being a diagnosis in and of itself. IBP is a common and important feature of axial spondyloarthritis (axSpA) but this is not the only differential. This review examines the utility of IBP in both primary and secondary care settings.

RECENT FINDINGS

There are a number of suggested referral strategies for patients with suspected axSpA that include IBP. These strategies attempt to strike a balance between ensuring potential axSpA patients are not overlooked, whilst simultaneously not overwhelming secondary care services. Their success relies on the clinicians who first encounter these patients being familiar with IBP as a concept; however, it is still poorly recognized by many healthcare professionals. IBP may be helpful as part of a referral strategy; however, other clinical features, laboratory investigations and radiology must be incorporated for the final diagnostic outcome in axSpA.

SUMMARY

Delayed diagnosis is a major clinical problem in axSpA and is associated with worse clinical outcomes. When recognized and utilized correctly, IBP can be a useful tool to promote prompt referral to rheumatology services.

Pre-surgical heart-rate variability strongly predicts less post-operative pain in patients with epilepsy

OBJECTIVES

Post-operative pain is a common clinical problem after surgery, yet its predictors are inconsistent and unclear. This study examined whether pre-surgical vagal cardiac efferent nerve activity, indirectly indexed by heart rate variability (HRV), predicts patients' pain after epileptic surgery.

METHODS

Using a prospective design, HRV was measured at rest during 5 min in n = 30 patients, prior to undergoing epileptic surgery. Post-operative pain was assessed every 8 h during the first 2 days after surgery, and our analyses focused on the worse pain level. We used multiple regression analyses and statistically considered several confounders (age, surgical duration, and analgesics during various surgical phases).

RESULTS

Multiple HRV indexes strongly and inversely predicted post-operative pain, with high-frequency HRV (HF-HRV) being the strongest predictor (r = -0.81, p < 0.001). In a hierarchical multiple regression, HF-HRV accounted for an additional and significant 18% of the variance in post-operative pain, after statistically considering effects of age, surgical duration and effects of two anaesthetics.

CONCLUSIONS

Pre-surgical HF-HRV independently, strongly and inversely predicts post-operative pain. These results are in line with a neuromodulatory role of the vagus nerve in pain and have clinical implications for predicting and managing post-operative pain.

Prevalence of inflammatory back pain and radiographic axial spondyloarthritis in a semi-urban community of Lahore, Pakistan

AIMS

To determine the prevalence of inflammatory back pain (IBP) and radiographic axial spondyloarthritis (SpA) in a semi-urban community of Lahore, Pakistan.

METHODS

This cross-sectional household survey was designed as per the Community Oriented Program for the Control of Rheumatic Diseases (COPCORD) model. In Phase 1, the subjects were interviewed for musculoskeletal (MSK) pain in the last 7 days by clinical assistants. In Phase 2, physiotherapists identified subjects with spinal/back pain and interviewed for Assessment in Spondyloarthritis International Working Group (ASAS) criteria for IBP. In Phase 3 subjects having IBP or chronic back pain (CBP) with an age at onset ≤45 years, were assessed and further investigated.

RESULTS

A total of 4922 subjects with a mean age of 35.3 ± 14.5 years, including 2770 (56%) women were surveyed in Phase 1. MSK pain in last 7 days was reported by 1407 (28.6%) of whom 1034 (21%) had spinal pain. The ASAS criteria for IBP were met in 329 (6.7%, 95% CI 6.0-7.0). In Phase 3, 222 with IBP and 83 having CBP with age at onset ≤45 years were evaluated. Out of this total of 305, 144 (2.9%) were confirmed to have IBP by rheumatologists as per at least 1 of the 3 criteria. ASAS criteria were met in 107 (2.2%, 95% CI 1.8-2.6). ASAS criteria for radiographic axial SpA were met in 47 (1%, 95% CI 0.7-1.3) of the surveyed population.

CONCLUSION

Inflammatory back pain was reported in 6.7% by physiotherapists, confirmed in 3% by rheumatologists. The prevalence of radiographic axial SpA was 1%.

Revisiting the gut-joint axis: links between gut inflammation and spondyloarthritis

Gut inflammation is strongly associated with spondyloarthritis (SpA), as exemplified by the high prevalence of inflammatory bowel disease (IBD) and the even higher occurrence of subclinical gut inflammation in patients with SpA. The gut-joint axis of inflammation in SpA is further reinforced by similarities in immunopathogenesis at both anatomical sites and by the clinical success of therapies blocking TNF and IL-23 in IBD and in some forms of SpA. Many genetic risk factors are shared between SpA and IBD, and changes in the composition of gut microbiota are seen in both diseases. Current dogma is that inflammation in SpA initiates in the gut and leads to joint inflammation; however, although conceptually attractive, some research does not support this causal relationship. For example, therapies targeting IL-17A are efficacious in the joint but not the gut, and interfering with gut trafficking by targeting molecules such as α4β7 in IBD can lead to onset or flares of SpA. Several important knowledge gaps remain that must be addressed in future studies. Determining the true nature of the gut-joint axis has real-world implications for the treatment of patients with co-incident IBD and SpA and for the repurposing of therapeutics from one disease to the other.

Early recognition of patients with axial spondyloarthritis—evaluation of referral strategies in primary care

Objective

Chronic inflammatory back pain (IBP) is frequently reported in axial SpA (axSpA) but also in the general population. We evaluated a recently proposed two-step referral system for early recognition of axSpA in primary care and compare it with other combinations of symptoms and SpA-related items.

Methods

Consecutive chronic back pain patients ≤45 years of age answered a questionnaire and were seen by a primary care physician who decided whether HLA-B27 needed to be determined. They were then referred to a rheumatologist who made the diagnosis. Generally sticking to the two-step system with HLA-B27 as an additional option, combinations with a sensitivity ≥90% and a likelihood ratio &gt;4 were compared.

Results

A total of 326 patients were included, 46 of whom were diagnosed with axSpA (14.1%). The sensitivity of the strategy was 87%, the specificity was 56.8% and the positive and negative predictive values were 24.8% and 96.4%, respectively. A ‘good response to NSAIDs’, ‘morning stiffness &gt;30 min’ and ‘elevated C-reactive protein’ performed best, with a sensitivity of 91%, specificity of 67%, positive predictive value of 31% and negative predictive value of 98%. On that basis, only three patients had to be seen by a rheumatologist to diagnose one.

Conclusion

The earlier proposed referral system worked well but was outperformed by other combinations with high sensitivity and better specificity, which deserve to be prospectively studied.

Diagnostic accuracy of inflammatory back pain for axial spondyloarthritis in rheumatological care

Objective

Inflammatory back pain (IBP), the key symptom of axial spondyloarthritis (axSpA), including ankylosing spondylitis, has been proposed as a screening test for patients presenting with chronic back pain in primary care. The diagnostic accuracy of IBP in the rheumatology setting is unknown.

Methods

Six rheumatology centres, representing secondary and tertiary rheumatology care, included routinely referred patients with consecutive chronic back pain with suspicion of axSpA. IBP (diagnostic test) was assessed in each centre by an independent (blinded) rheumatologist; a second (unblinded) rheumatologist made the diagnosis (axSpA or no-axSpA), which served as reference standard.

Results

Of 461 routinely referred patients, 403 received a final diagnosis. IBP was present in 67.3%, and 44.6% (180/403) were diagnosed as axSpA. The sensitivity of IBP according to various definitions (global judgement, Calin, Berlin, Assessment of SpondyloArthritis international Society criteria for IBP) was 74.4%–81.1 % and comparable to published figures, whereas the specificity was unexpectedly low (25.1%–43.9%). The resulting positive likelihood ratios (LR+) were 1.1–1.4 and without major differences between sets of IBP criteria. The presence of IBP according to various definitions increased the probability of axSpA by 2.5%–8.4% only (from 44.6% to 47.1%–53.0%).

Conclusions

The diagnostic utility of IBP in the rheumatology setting was smaller than expected. However, this was counterbalanced by a high prevalence of IBP among referred patients, demonstrating the effective usage of IBP in primary care as selection parameter for referral to rheumatology. Notably, this study illustrates potential shifts in specificity and LR+ of diagnostic tests if these tests are used to select patients for referral.

Postpartum Bone Marrow Edema at the Sacroiliac Joints May Mimic Sacroiliitis of Axial Spondyloarthritis on MRI

OBJECTIVE

The objective of our study was to compare MRI findings in the sacroiliac joints of postpartum women (as a model of mechanical changes) and women with known axial spondyloarthritis (as an inflammatory model).

SUBJECTS AND METHODS

For this prospective multicenter age-matched, case-control study, sacroiliac joint MRI examinations of 30 healthy women (mean age, 34.0 years) in the early postpartum period (mechanical group) and 30 age-matched women (mean age, 33.8 years) with known axial spondyloarthritis (retrospective inflammatory group) were compared. Blinded to clinical information, readers assessed MR images using the following scoring systems: Spondyloarthritis Research Consortium of Canada (SPARCC) MRI index, Berlin method, Assessment of Spondyloarthritis International Society (ASAS) criteria, and SPARCC MRI structural score. Descriptive statistics as percentages of the different findings (i.e., bone marrow edema [BME], erosion, fatty bone marrow replacement, backfill, ankylosis) and scores between groups and between delivery modes were compared.

RESULTS

In the postpartum group, 63.3% (19/30) of women showed BME around the sacroiliac joints compared with 86.7% (26/30) of women in the spondyloarthritis group (based on ASAS criteria). Erosions were uncommon in the postpartum group (10.0% [3/30] postpartum vs 56.7% [17/30] spondyloarthritis). Fatty bone marrow replacement, backfill, and ankylosis were not seen in the postpartum group. In subjects with positive MRI findings for sacroiliitis based on ASAS criteria, the SPARCC MRI index (mean ± SD, 13.6 ± 14.5 vs 13.0 ± 10.7; p = 0.818) and Berlin method (4.5 ± 3.0 and 5.5 ± 3.5, p = 0.378) were not different between the postpartum and spondyloarthritis groups. Scores were not different between birth modalities.

CONCLUSION

Pregnancy-induced BME at the sacroiliac joints, as a result of prolonged mechanical stress, was present in 63.3% of women who underwent MRI during the early postpartum period and may mimic sacroiliitis of axial spondyloarthritis.

Ca2+-binding protein NECAB2 facilitates inflammatory pain hypersensitivity

Pain signals are transmitted by multisynaptic glutamatergic pathways. Their first synapse between primary nociceptors and excitatory spinal interneurons gates the sensory load. In this pathway, glutamate release is orchestrated by Ca2+-sensor proteins, with N-terminal EF-hand Ca2+-binding protein 2 (NECAB2) being particular abundant. However, neither the importance of NECAB2+ neuronal contingents in dorsal root ganglia (DRGs) and spinal cord nor the function determination by NECAB2 has been defined. A combination of histochemical analyses and single-cell RNA-sequencing showed NECAB2 in small- and medium-sized C- and Aδ D-hair low-threshold mechanoreceptors in DRGs, as well as in protein kinase C γ excitatory spinal interneurons. NECAB2 was downregulated by peripheral nerve injury, leading to the hypothesis that NECAB2 loss of function could limit pain sensation. Indeed, Necab2-/- mice reached a pain-free state significantly faster after peripheral inflammation than did WT littermates. Genetic access to transiently activated neurons revealed that a mediodorsal cohort of NECAB2+ neurons mediates inflammatory pain in the mouse spinal dorsal horn. Here, besides dampening excitatory transmission in spinal interneurons, NECAB2 limited pronociceptive brain-derived neurotrophic factor (BDNF) release from sensory afferents. Hoxb8-dependent reinstatement of NECAB2 expression in Necab2-/- mice then demonstrated that spinal and DRG NECAB2 alone could control inflammation-induced sensory hypersensitivity. Overall, we identify NECAB2 as a critical component of pronociceptive pain signaling, whose inactivation offers substantial pain relief.

An epidemiological study of the prevalence rate of inflammatory back pain and axial spondyloarthritis in a university in the south of China

Inflammatory back pain (IBP) is an important clinical feature for axial spondyloarthritis (SpA). Yet, little is known about their prevalences in China. We conducted an epidemiological study in a university to detect the prevalences of IBP and axial SpA according to the Assessment of SpondyloArthritis International Society (ASAS) criteria. We investigated 3770 participants from South China Agricultural University by face-to-face questionnaires and evaluated the prevalences of chronic low back pain (CLBP) and IBP. In addition, 333 students including all IBP patients volunteered to do HLA-B27 test, and we performed X-ray examination on students with suspect axial SpA. Axial SpA was confirmed by rheumatologists according to ASAS criteria. The mean (± SD) age of screened population was 19.48 (± 2.80) years, while female to male ratio was 1.45:1 (2229/1541). Seven hundred thirty-one (19.39%) of all participants had CLBP and 111 (2.94%) had IBP. Among the 333 students receiving HLA-B27 test, 13 (0.34%, 13/3770) fulfilled ASAS criteria for axial SpA. Nine students had sacroiliitis on imaging plus at least one SpA feature (IBP and positive HLA-B27 results). Four students had positive HLA-B27 plus at least two other SpA features (arthritis/enthesitis and good response to NSAIDs). For CLBP, female/male was 485/246. For axial SpA, female/male was 4/9(P = 0.014). In southern China, the prevalences of CLBP and IBP were respectively 19.39 and 2.94% in university, and the prevalence of axial SpA was 0.34%. Although more female students had CLBP, males were more likely to suffer from axial SpA.

Clinical Evolution in Patients With New-Onset Inflammatory Back Pain: A Population-Based Cohort Study

OBJECTIVE

Inflammatory back pain (IBP) is often an early manifestation of spondyloarthritis (SpA), but the prognosis of patients with incident IBP is unknown. This study was undertaken to investigate long-term outcomes in patients with IBP, and predictors of progression to SpA, in a population-based cohort.

METHODS

We conducted a retrospective, longitudinal study using the Rochester Epidemiology Project, a longstanding population-based cohort of residents of Olmsted County, MN. Patients ages 16-35 years with clinical visits for back pain from 1999 to 2003 were identified, and we screened these patients for the presence of new-onset IBP and performed medical record reviews to collect data on clinical, laboratory, and imaging features of SpA. Outcomes in these patients were followed up until July 2016. We used survival analysis for competing risks to examine progression to either SpA, a non-SpA diagnosis, or resolution of back pain. Recursive partitioning was used to identify predictors of progression to SpA.

RESULTS

Among 5,304 patients with back pain, we identified 124 patients with new-onset IBP. After a median follow-up of 13.2 years, IBP had progressed to SpA in 39 patients, 15 patients developed a non-SpA diagnosis, and 58 patients had resolution of IBP. At 10 years, the probability of having SpA was 30%, while the probability of resolution of IBP was 43%. The most important predictors for progression to SpA were uveitis, male sex, and family history of SpA.

CONCLUSION

In a minority of patients, new-onset IBP progresses to SpA, while IBP resolves in many. That IBP often resolves may explain the difference between the prevalence of IBP (3-6%) and the prevalence of SpA (0.4-1.3%).

Inflammatory back pain and associated disease conditions among patients with chronic low back pain in Bangladesh

AIM

Inflammatory back pain (IBP) is the earliest symptom of axial and other forms of spondyloarthritis (SpA). However, there are no published data on prevalence of IBP among patients suffering from chronic low back pain (CLBP) in Bangladesh. In this study, we estimated the prevalence of IBP and the subtypes of SpA in a tertiary hospital in Bangladesh.

METHODS

This 1 year cross-sectional study was conducted among 240 CLBP patients in a rheumatology outpatient clinic. Assessment of Spondyloarthritis International Society classification criteria of IBP and predefined recognized classification criteria were followed to define different subtypes of SpA. Means and standard deviations were reported for continuous variables. Descriptive and bi-variate analyses were accordingly performed.

RESULTS

Of 240 CLBP patients, 60 (25%) had IBP and 180 (75%) had mechanical back pain (MBP). Among the 60 IBP patients, 52 (86.6%) had predominantly axial SpA (axSpA) and eight (13.4%) had predominantly peripheral spondyloarthritis. In the axSpA group, 49 (94.2%) had radiographic axSpA (rd-axSpA) also known as AS and three (5.8%) had non-radiographic axSpA (nr-axspA). AxSpA patients could be divided into eight (15.35%) with psoriasis, two (3.8%) with reactive arthritis and one patient (1.9%) had arthritis associated with inflammatory bowel disease. Fifty (83.3%) IBP and 73 (40.6%) MBP patients had age at onset of back pain < 40 years. Forty-two (70%) of the IBP and 100 (55.6%) of the MBP patients had normal body mass index. All these differences were statistically significant (P ≤ 0.0001).

CONCLUSIONS

Inflammatory back pain is common among patients presenting with CLBP. The commonest cause of IBP is AS, followed by PsA and nr-axSpA.

Ankylosing Spondylitis and Axial Spondyloarthritis in Patients With Long-term Inflammatory Bowel Disease: Results From 20 Years of Follow-up in the IBSEN Study

BACKGROUND

Patients with inflammatory bowel disease [IBD] often suffer from rheumatic manifestations, including inflammatory back disorders. The prevalence of these disorders late in the course of IBD is poorly investigated. The aim of this study was to estimate the prevalence of inflammatory back disorders in patients with IBD 20 years after diagnosis, and to investigate possible associations with IBD severity, HLA-B27, and the NOD2 genotype.

METHODS

A population-based cohort [the IBSEN study] was followed prospectively for 20 years. Information covering IBD activity and rheumatic diseases was collected at the regular follow-ups. HLA-B27 and NOD2 were analysed as present or absent.

RESULTS

At 20 years, 599 members of the original cohort were alive, of whom 470 [78.5%] were investigated [314 ulcerative colitis and 156 Crohn's disease patients]. Ankylosing spondylitis was diagnosed in 21 patients [4.5%], axial spondyloarthritis was diagnosed in 36 patients [7.7%], and inflammatory back pain was diagnosed in 54 patients [11.5%]. Chronic back pain [back pain > 3 months] was present in 220 patients [46.8%]. HLA-B27 was associated with ankylosing spondylitis, axial spondyloarthritis, and inflammatory back pain, whereas no significant association was found for NOD2. A more chronic IBD course was associated with axial spondyloarthritis.

CONCLUSIONS

Our data revealed a high prevalence of ankylosing spondylitis, axial spondyloarthritis, and inflammatory back pain 20 years after the IBD diagnosis. HLA-B27 but not NOD-2 was a predisposing factor for the inflammatory back disorders in IBD patients. Axial spondyloarthritis was associated with a more chronic active IBD disease course.

Management of acute pain in the postoperative setting: the importance of quality indicators

Despite the introduction of evidence-based recommendations for postoperative pain management (POPM), the consensus is that pain control remains suboptimal. Barriers to achieving patient-satisfactory analgesia include deficient knowledge regarding POPM among staff, lack of instructions, insufficient pain assessments and sub-optimal treatment. Effective monitoring of POPM is essential to enable policy makers and healthcare providers to improve the quality of care. Quality indicators (QIs) are quantitative measures of clinical practice that can monitor, evaluate and guide the quality of care provided to patients. QIs can be used to assess various aspects relating to the care process and they have proven useful in improving health outcomes in diseases such as myocardial infarction. In this commentary we critically analyze the evidence regarding the use of QIs in acute POPM based upon the experience of pain specialists from Europe and the USA who are members of the Change Pain Advisory Board. We also undertook a literature review to see what has been published on QIs in acute pain with the goal of assessing which QIs have been developed and used, and which ones have been successful/unsuccessful. In the hospital sector the development and implementation of QIs is complex. The nature of POPM requires a highly trained, multidisciplinary team and it is at this level that major improvements can be made. Greater involvement of patients regarding pain management is also seen as a priority area for improving clinical outcomes. Changes in structure and processes to deliver high-level quality care need to be regularly audited to ensure translation into better outcomes. QIs can help drive this process by providing an indicator of current levels of performance. In addition, outcomes QIs can be used to benchmark levels of performance between different healthcare providers.

Gray matter alteration associated with pain catastrophizing in patients 6 months after lumbar disk surgery: a voxel-based morphometry study

Supplemental Digital Content is Available in the Text.

The link between pain catastrophizing and the differential effect of the components magnification and helplessness on brain morphology in patients with low back pain

Introduction:

Pain catastrophizing (PC), the increased attention to harmful aspects of pain (magnification), and the belief of low controllability (helplessness) has been shown to be important in the maintenance of pain. A growing research on structural alterations in chronic pain revealed an association between PC and brain areas that are involved in affective and cognitive pain processing. However, little is known about a differential effect of the components magnification and helplessness.

Objective:

The aim of this study was to identify brain regions associated with overall PC and with the single components of magnification and helplessness.

Methods:

We investigated 29 patients 6 months after lumbar disk surgery using voxel-based morphometry. Magnification and helplessness were assessed with subscales of the Avoidance-Endurance Questionnaire (AEQ); overall PC was computed using the sum score. The structural brain imaging data were preprocessed and analyzed using SPM8 and VBM8. Multiple regression analyses were performed with PC scales as predictors and depression as covariate.

Results:

Pain catastrophizing was significantly associated with cortical gray matter in brain areas involved in processing attentional, sensory, and affective aspects of pain, including the left posterior cingulate cortex, supplementary motor area, and medial frontal gyrus. In addition, we provide preliminary evidence for brain structure association related to magnification and helplessness.

Conclusion:

This study provides evidence for PC-related structural alterations in patients with low back pain, which are consistent with findings from previous research in different chronic pain disorders. This study is the first to evaluate brain changes related to differential domains of PC.

The prevalence of axial spondyloarthritis in the UK: a cross-sectional cohort study

Background

Accurate prevalence data are important when interpreting diagnostic tests and planning for the health needs of a population, yet no such data exist for axial spondyloarthritis (axSpA) in the UK. In this cross-sectional cohort study we aimed to estimate the prevalence of axSpA in a UK primary care population.

Methods

A validated self-completed questionnaire was used to screen primary care patients with low back pain for inflammatory back pain (IBP). Patients with a verifiable pre-existing diagnosis of axSpA were included as positive cases. All other patients meeting the Assessment of SpondyloArthritis international Society (ASAS) IBP criteria were invited to undergo further assessment including MRI scanning, allowing classification according to the European Spondyloarthropathy Study Group (ESSG) and ASAS axSpA criteria, and the modified New York (mNY) criteria for ankylosing spondylitis (AS).

Results

Of 978 questionnaires sent to potential participants 505 were returned (response rate 51.6 %). Six subjects had a prior diagnosis of axSpA, 4 of whom met mNY criteria. Thirty eight of 75 subjects meeting ASAS IBP criteria attended review (mean age 53.5 years, 37 % male). The number of subjects satisfying classification criteria was 23 for ESSG, 3 for ASAS (2 clinical, 1 radiological) and 1 for mNY criteria. This equates to a prevalence of 5.3 % (95 % CI 4.0, 6.8) using ESSG, 1.3 % (95 % CI 0.8, 2.3) using ASAS, 0.66 % (95 % CI 0.28, 1.3) using mNY criteria in chronic back pain patients, and 1.2 % (95 % CI 0.9, 1.4) using ESSG, 0.3 % (95 % CI 0.13, 0.48) using ASAS, 0.15 % (95 % CI 0.02, 0.27) using mNY criteria in the general adult primary care population.

Conclusions

These are the first prevalence estimates for axSpA in the UK, and will be of importance in planning for the future healthcare needs of this population.

Trial registration

Current Controlled Trials ISRCTN76873217

Increase in Dickkopf-1 Serum Level in Recent Spondyloarthritis. Data from the DESIR Cohort

OBJECTIVES

To investigate DKK-1 and SOST serum levels among patients with recent inflammatory back pain (IBP) fulfilling ASAS criteria for SpA and associated factors.

METHODS

The DESIR cohort is a prospective, multicenter French cohort of 708 patients with early IBP (duration >3 months and <3 years) suggestive of AxSpA. DKK-1 and SOST serum levels were assessed at baseline and were compared between the subgroup of patients fulfilling ASAS criteria for SpA (n = 486; 68.6%) and 80 healthy controls.

RESULTS

Mean SOST serum levels were lower in ASAS+ patients than healthy controls (49.21 ± 25.9 vs. 87.8 ± 26 pmol/L; p<0.0001). In multivariate analysis, age (p = 5.4 10-9), CRP level (p<0.0001) and serum DKK-1 level (p = 0.001) were associated with SOST level. Mean DKK-1 serum levels were higher in axial SpA patients than controls (30.03 ± 15.5 vs. 11.6 ± 4.2 pmol/L; p<0.0001). In multivariate analysis, DKK-1 serum levels were associated with male gender (p = 0.03), CRP level (p = 0.006), SOST serum level (p = 0.002) and presence of sacroiliitis on radiography (p = 0.05). Genetic association testing of 10 SNPs encompassing the DKK-1 locus failed to demonstrate a significant contribution of genetics to control of DKK-1 serum levels.

CONCLUSIONS

DKK-1 serum levels were increased and SOST levels were decreased among a large cohort of patients with early axial SpA compared to healthy controls. DKK-1 serum levels were mostly associated with biological inflammation and SOST serum levels.

Prevalence of Inflammatory Back Pain and Axial Spondyloarthritis Among University Employees in Izmir, Turkey

Objective.

To estimate the prevalence of inflammatory back pain (IBP) and axial spondyloarthritis (axSpA) using the Assessment of SpondyloArthritis International Society (ASAS) classification criteria among employees in a university.

Methods.

In the first stage of the study, a face-to-face interview was done using a standard questionnaire to investigate IBP in 381 subjects randomly selected from 2894 employees at Dokuz Eylul University in Izmir, Turkey. In the second stage, subjects with back pain for ≥ 3 months and age at onset < 45 years were evaluated for axSpA using the ASAS criteria. Both the European Spondyloarthropathy Study Group (ESSG) criteria and Amor criteria were used for the classification of the whole group of spondyloarthritis (SpA).

Results.

There were 131 male and 250 female subjects (mean age: 38.0 yrs). Twenty-five subjects (6.6%) were classified as having IBP according to the ASAS criteria. The prevalence of IBP according to the Berlin and Calin criteria was 7.1% and 21.5%, respectively. The prevalence of axSpA was estimated at 1.3% according to the ASAS classification criteria (0.5% for radiographic axSpA and 0.8% for nonradiographic axSpA). A total of 7 patients (1.8%) fulfilled both the Amor and ESSG criteria for the whole group of SpA.

Conclusion.

This is the first prevalence study of IBP and axSpA using ASAS classification criteria in the Turkish population. The prevalence estimates of IBP and axSpA reported here are within the upper range of other studies in European countries and the United States.

Diagnostic clinical prediction rules for specific subtypes of low back pain: a systematic review

STUDY DESIGN

Systematic review.

OBJECTIVES

To identify diagnostic clinical prediction rules (CPRs) for low back pain (LBP) and to assess their readiness for clinical application.

BACKGROUND

Significant research has been invested into the development of CPRs that may assist in the meaningful subgrouping of patients with LBP. To date, very little is known about diagnostic forms of CPRs for LBP, which relate to the present status or classification of an individual, and whether they have been developed sufficiently to enable their application in clinical practice.

METHODS

A sensitive electronic search strategy using 7 databases was combined with hand searching and citation tracking to identify eligible studies. Two independent reviewers identified relevant studies for inclusion using a 2-stage selection process. The quality appraisal of included studies was conducted by 2 independent raters using the Quality Assessment of Diagnostic Accuracy Studies-2 and checklists composed of accepted methodological standards for the development of CPRs.

RESULTS

Of 10 014 studies screened for eligibility, the search identified that 13 diagnostic CPRs for LBP have been derived. Among those, 1 tool for identifying lumbar spinal stenosis and 2 tools for identifying inflammatory back pain have undergone validation. No impact analysis studies were identified.

CONCLUSION

Most diagnostic CPRs for LBP are in their initial development phase and cannot be recommended for use in clinical practice at this time. Validation and impact analysis of the diagnostic CPRs identified in this review are warranted, particularly for those tools that meet an identified unmet need of clinicians who manage patients with LBP.

LEVEL OF EVIDENCE

Diagnosis, level 2a-.

Ultrasonography as a useful modality for documenting sacroiliitis in radiographically negative inflammatory back pain: a comparative evaluation with MRI

OBJECTIVES

The aims of this study were to identify and characterize features of sacroiliitis in patients with non-radiographic inflammatory low back pain by ultrasonography (USG) and to correlate the findings with that of MRI.

METHODS

MRI and USG of SI joints were performed on 29 patients who fulfilled the definition of inflammatory low back pain according to the Assessment of SpondyloArthritis International Society 2009 criteria for axial SpA but were X-ray negative for sacroiliitis. Increased vascularity, low resistive index (RI) and hyperechogenicity of the joint space were considered USG features of sacroiliitis. The findings were compared with those of 32 controls. USG features of sacroiliitis were compared with MRI by κ statistics.

RESULTS

Receiver operating characteristic analysis revealed cut-off values for flow signals and RI of 3 and 0.605, respectively. There was a significant difference in the number of flow signals, RI and echogenicity of the SI joint between MRI-proven cases and controls. The Cohen's κ for flow signals, RI and hyperechogenicity when compared with MRI were 0.816 (95% CI 0.676, 0.937) and 0.821 (95% CI 0.662, 0.965) and 0.403 (95% CI 0.108, 0.695). Taking both flow signals and RI parameters as criteria for determining sacroiliitis, comparison with MRI returned a κ of 0.816 (95% CI 0.601, 0.963).

CONCLUSION

Three or more flow signals and a RI ≤0.605 can be applied as USG criteria for sacroiliitis. USG can be a cost-effective and non-inferior modality compared with MRI in documenting sacroiliitis in early SpA.