Development of a radiographic index to assess the tarsal involvement in patients with spondyloarthropathies

Complete Bilateral Ankle Fusion: A Rare Complication of Ankylosing Spondylitis

Ankylosing spondylitis (AS) is a chronic inflammatory disorder primarily affecting the axial skeleton and is strongly associated with a positive human leukocyte antigen B27 (HLA-B27) genotype. Patients typically present with chronic low back pain that typically starts before the age of 40 years. Common initial clinical features include lower back, hip, and joint pain with stiffness that is worse in the morning and with inactivity. As the disease progresses over a prolonged period, it leads to fusion of sacroiliac joints and ankylosis of the vertebrae with the iconic "bamboo spine" on imaging. Joint fusion or ankylosis is the sequela of either undiagnosed or untreated AS. We report a case of a 69-year-old male with complete fusion of the ankle joint, hindfoot, and midfoot of both feet in the clinical context of an incidental finding of an ankylosed spine on computed tomography (CT) imaging. The ankle joint is a very uncommon site for fusion in ankylosing spondylitis. We would like to suggest the terminology “boot sign” for this rare radiographic finding of complete ankle and subtalar fusion given the appearance of a boot. “Boot sign” is associated with either inability to ambulate or a steppage gait from loss of ankle dorsiflexion as a result of ankle and hindfoot fusion with or without fusion of forefoot and midfoot.

Pachydermodactyly: the role of ultrasonography, superb microvascular imaging, and elastography in diagnosis

Pachydermodactyly is a rare and benign superficial fibromatosis characterized by painless and progressive swelling of periarticular soft tissues of the proximal interphalangeal (PIP) joints, most commonly of both hands. There is no tenderness, warmth, morning stiffness, or reduced range of motion associated. Our purpose is to highlight the diagnostic utility of ultrasonography, superb microvascular imaging (SMI), and elastography in pachydermodactyly. We report the case of a 15-year-old adolescent white boy, with a 6-month history of insidious and progressive, asymptomatic swelling of the lateral and dorsal regions of the metacarpophalangeal (MCP), and PIP joints of both hands. Articular ultrasonography showed thickening of the skin around the lateral regions of the PIP and MCP joints, with no synovitis, hydrarthrosis, or muscle, tendon, or bone changes. Strain elastography revealed lower elasticity in the aforementioned skin regions, corresponding to increased tissue hardness due to hyperkeratosis. No SMI or Doppler signals were detected in epidermal or dermal tissues, as well as in tendons, joints, and bone. This case report shows that ultrasonography, SMI, and elastography may play a significant role in the accurate diagnosis of pachydermodactyly and exclusion of alternative conditions. These imaging modalities have no ionizing radiation; they are fast, inexpensive, and performed on site. They do not require usage of contrast agents and thus can eliminate the need of invasive procedures such as skin biopsy. They also contribute to reduce health care costs with unnecessary complementary tests and inappropriate treatment.

Inflammatory Foot Involvement in Spondyloarthritis: From Tarsitis to Ankylosing Tarsitis

Spondyloarthritis (SpA) is a group that includes a wide spectrum of clinically similar diseases manifested by oligoarticular arthritis and axial or peripheral ankylosis. Although axial SpA is predominant in Caucasians and adult-onset patients, juvenile-onset and Latin American patients are characterized by severe peripheral arthritis and particularly foot involvement. The peripheral involvement of SpA can vary from tarsal arthritis to the most severe form named ankylosing tarsitis (AT). Although the cause and etiopathogenesis of axSpA are often studied, the specific characteristics of pSpA are unknown. Several animal models of SpA develop initial tarsitis and foot ankylosis as the main signs, emphasizing the role of foot inflammation in the overall SpA spectrum. In this review, we attempt to highlight the clinical characteristics of foot involvement in SpA and update the knowledge regarding its pathogenesis, focusing on animal models and the role of mechanical forces in inflammation.

Worldwide Differences in Clinical Phenotype of Axial Spondyloarthritis

PURPOSE OF REVIEW

This review aims to describe the variations in the clinical presentation of axial spondyloarthritis (axSpA) across the globe.

RECENT FINDINGS

We searched the PubMed database and screened more than 1360 articles; 60 of them were selected based on relevance to the topic being discussed and the goals of the review. Most of the clinical manifestations, including IBP, peripheral arthritis, and extra-articular involvement are seen in different regions of the world, but with appreciable clinical heterogeneity, possibly related to a smaller number of patients from some countries, and global variation in the prevalence of HLA-B27. For example, HLA-B27-positive patients have an earlier age of onset, higher prevalence of acute anterior uveitis, and greater familial occurrence. Peripheral arthritis and enthesitis are most commonly seen among axSpA patients from Latin America and Asia, whereas IBD appears to be slightly more common among Middle Eastern and North African patients. The main weakness encountered while reviewing these data is that some studies were small, and others were cross-sectional and retrospective; hence the inferences may have a selection bias. AxSpA is a very heterogenous disease with varied presentation across the globe, in part related to HLA-B27 positivity. It is imperative to further investigate the key regional differences as they impact timely disease recognition and initiation of early treatment. Therefore, there is a need for a large worldwide systematic study to capture the clinical picture of AxSpA in a more uniform manner.

Prevalence and distribution of peripheral musculoskeletal manifestations in spondyloarthritis including psoriatic arthritis: results of the worldwide, cross-sectional ASAS-PerSpA study

OBJECTIVES

To characterise peripheral musculoskeletal involvement in patients with spondyloarthritis (SpA) including psoriatic arthritis (PsA), across the world.

METHODS

Cross-sectional study with 24 participating countries. Patients with a diagnosis of axial SpA (axSpA), peripheral SpA (pSpA) or PsA according to their rheumatologist were included. The investigators were asked which diagnosis out of a list of six (axSpA, PsA, pSpA, inflammatory bowel disease-associated SpA, reactive arthritis or juvenile SpA (Juv-SpA)) fitted the patient best. Peripheral manifestations (ie, peripheral joint disease, enthesitis, dactylitis and root joint disease), their localisation and treatments were evaluated.

RESULTS

A total of 4465 patients were included (61% men, mean age 44.5 years) from four geographic areas: Latin America (n=538), Europe plus North America (n=1677), Asia (n=975) and the Middle East plus North Africa (n=1275). Of those, 78% had ever suffered from at least one peripheral musculoskeletal manifestation; 57% had peripheral joint disease, 44% had enthesitis and 15% had dactylitis. Latin American had far more often peripheral joint disease (80%) than patients from other areas. Patients with PsA had predominantly upper limb and small joint involvement (52%).Hip and shoulder involvement was found in 34% of patients. The prevalence of enthesitis ranged between 41% in patients with axSpA and 65% in patients with Juv-SpA. Dactylitis was most frequent among patients with PsA (37%).

CONCLUSION

These results suggest that all peripheral features can be found in all subtypes of SpA, and that differences are quantitative rather than qualitative. In a high proportion of patients, axial and peripheral manifestations coincided. These findings reconfirm SpA clinical subtypes are descendants of the same underlying disease, called SpA.

Functional limitations due to foot involvement in spondyloarthritis

[Purpose] Spondyloarthritis is a major inflammatory disease followed-up in the rheumatology clinics, foot involvement in spodyloarthritis is common. The functional states of patients with spondyloarthritis are usually evaluated globally. The aim of this study was to assess the foot involvement-related functional limitations in patients with spondyloarthritis. [Subjects and Methods] Patients with ankylosing spondylitis and psoriatic arthritis with foot pain more than 4 weeks who underwent anteroposterior and lateral feet radiography were enrolled into the study. A “clinical findings score” was calculated by assigning 1 point for every finding of swelling, redness, and tenderness. C-reactive protein and erythrocyte sedimentation rate were used as serum markers for disease activity. Foot radiograms were evaluated using the spondyloarthropathy tarsal radiographic index and the foot-related functional state of patients was determined by the Turkish version of the Foot and Ankle Outcome Score. [Results] There were no relationships between Foot and Ankle Outcome Score subscales and clinical findings score, serum markers, or radiologic score. Pain and symptoms subscale scores were result positively correlated with activity of daily living, sport and recreation, and quality of life subscale scores. [Conclusion] Pain and symptoms are the main determinants of foot-related functional limitations in spondyloarthritis.

Bone Lineage Proteins in the Entheses of the Midfoot in Patients with Spondyloarthritis

Objective.

Patients with juvenile-onset spondyloarthritis (SpA) may develop ankylosis of the midfoot resembling the spinal changes seen in patients with ankylosing spondylitis (AS). The study of the histopathology of the feet of patients with tarsitis could help us understand the pathogenesis of bone formation in affected structures in the SpA. The objective of our study was to describe the histopathologic characteristics of the midfoot in patients with tarsitis associated with SpA.

Methods.

We obtained synovial sheaths, entheses, and bone samples from 20 patients with SpA with midfoot pain/tenderness and swelling. Tissue samples underwent H&E staining; immunohistochemistry for CD3, CD4, CD8, CD68, and CD20 cell identification; and immunofluorescence for bone lineage proteins, including osteocalcin, osteopontin, parathyroid hormone-related protein, bone sialoprotein, and alkaline phosphatase.

Results.

Slight edema and hyalinization were found in some tendon sheaths, and few inflammatory cells were detected in the entheses. In bones, we found some changes suggesting osteoproliferation, including endochondral and intramembranous ossification, but no inflammatory cells. In entheses showing bone proliferation, we detected osteocalcin and osteopontin in cells with a fibroblast-mesenchymal phenotype, suggesting the induction of entheseal cells toward an osteoblast phenotype.

Conclusion.

Osteoproliferation and abnormal expression of bone lineage proteins, but no inflammatory infiltration, characterize midfoot involvement in patients with SpA. In this sense, tarsitis (or ankylosing tarsitis) resembles the involvement of the spine in patients with AS. Ossification may be in part explained by the differentiation of mesenchymal entheseal cells toward the osteoblastic lineage.

Ultrasound detection of entheseal insertions in the foot of patients with spondyloarthropathy

The aim of the study was to evaluate entheseal involvement in the foot of patients with spondyloarthropathy (SpA) by ultrasonographic (US) examination and compare the results with clinical and radiological findings. Forty-four patients (27 men, 17 women) with a diagnosis of SpA were recruited. Patient evaluation included physical examination (swelling and pain), Bath Ankylosing Spondylitis Radiological Index, Bath Ankylosing Spondylitis Disease Activity, Bath Ankylosing Spondylitis Metrological Index, and laboratory parameters (erythrocyte sedimentation rate, C-reactive protein). Foot x-rays of the patients were assessed and scored according to SpA Tarsal Radiographic Index (SpA-TRI). A high-resolution US was used to examine the tendon and ligament insertion sites in the foot, and the findings were scored according to Glasgow Ultrasound Enthesitis Scoring System (GUESS). The mean age and disease duration of the patients were 39.9+/-12.5 and 9+/-8.2 years, respectively. US revealed pathological findings in 25 of 44 (56.8%) patients, most of whom exhibited no clinical signs of foot involvement. Pain and swelling at entheseal insertions were detected in only 16 (37%) patients. The mean GUESS score and SpA-TRI score were 2.2+/-2.5 and 3.3+/-3.7, respectively. There was a correlation between the scores of GUESS and SpA-TRI, particularly at the Achilles and plantar fascia insertion sites. The mean score of SpA-TRI was higher in patients with enthesopathy, detected by US, than in patients without enthesopathy (4.6+/-4.4 vs 1.8+/-2.1). There was no significant correlation between the mean GUESS score and clinical and laboratory variables. In conclusion, involvement of tendon and entheses is not rare, and US is a valuable diagnostic method in detecting subclinical enthesopathic changes. The GUESS and SpA-TRI are suggested in quantifying US and radiological changes in the foot of patients with SpA.

MR imaging features of foot involvement in ankylosing spondylitis

OBJECTIVE

To determine alterations of the soft tissue, tendon, cartilage, joint space, and bone of the foot using magnetic resonance (MR) imaging in ankylosing spondylitis (AS) patients.

MATERIALS AND METHOD

Clinical and MR examination of the foot was performed in 23 AS patients (46 feet). Ten asymptomatic volunteers (20 feet) were studied on MR imaging, as a control group. MR imaging protocol included; T1-weighted spin-echo, T2-weighted fast-field echo (FFE) and fat-suppressed short tau inversion recovery (STIR) sequences in sagittal, sagittal oblique, and coronal planes using a head coil. Specifically, we examined: bone erosions, tendinitis (acute and chronic), para-articular enthesophyte, joint effusion, plantar fasciitis, joint space narrowing, soft tissue edema, bone marrow edema, enthesopathy in the Achilles tendon and plantar fascia attachment, subchondral signal intensity abnormalities (edema and sclerosis), tenosynovitis, retrocalcaneal bursitis, subchondral cysts, subchondral fissures, and bony ankylosis. Midfoot, hindfoot, and ankle were included in examined anatomic regions.

RESULTS

Clinical signs and symptoms (pain and swelling) due to foot involvement were present in 3 (13%) of the patients while frequency of involvement was 21 (91%) with MR imaging assessment. The MR imaging findings were bone erosions (65%), Achilles tendinitis (acute and chronic) (61%), para-articular enthesophyte (48%), joint effusion (43%), plantar fasciitis (40%), joint space narrowing (40%), subchondral sclerosis (35%), soft tissue edema (30%), bone marrow edema (30%), enthesopathy of the Achilles attachment (30%), subchondral edema (26%), enthesopathy in the plantar fascia attachment (22%), retrocalcaneal bursitis (22%), subchondral cysts (17%), subchondral fissures (17%), tendinitis and enthesopathy of the plantar ligament (13%), and bony ankylosis (9%). The most common involved anatomical region was the hindfoot (83%) following by midfoot (69% ) and ankle (22%).

CONCLUSION

In our experience, MR imaging may detect inflammatory and/or erosive bone, soft tissue, cartilage, tendon, and joint abnormalities in AS patients, even if AS patients did not have clinical signs and symptoms of foot involvement. If these data prove to be confirmed in further MR studies, MR imaging may be of importance especially in early diagnosis of inflammatory changes in the foot.

Juvenile spondyloarthropathy

The juvenile-onset spondyloarthropathies are a group of pediatric disorders characterized by arthropathy and enthesopathy and a variety of extra-articular symptoms. With the application of new classification criteria, there is an increasing recognition of these diseases. This review summarizes recent advances in etiologic factors, clinical manifestations, therapeutics, and prognosis. Improved recognition of juvenile-onset spondyloarthropathies has allowed systematic and rigorous treatment trials to evaluate clinical outcomes relevant to pediatric medicine. Thus far, current therapeutic options allow for symptomatic control only. Further treatment studies are needed to examine the possibility of disease modification of juvenile-onset spondyloarthropathies.

Regional musculoskeletal conditions: foot and ankle disorders

Foot pain is very common, especially in women, owing to inappropriate footwear. Overuse, repetitive strain and minor, easily forgettable injuries may result in chronic foot and ankle pain. Rheumatoid arthritis, spondyloarthropathies and gout frequently affect the foot, often as a first presentation. Charcot's joints and foot infections are not rare in diabetes. The rheumatologist should be familiar with foot disorders, either localized or as manifestations of generalized disease. History taking, physical examination, identification of the source of pain by intra-articularly given local anaesthetics and imaging methods should be used to reveal the underlying disorder. Correct diagnosis and efficient therapy-including local steroid injections, physiotherapy, orthoses, surgery-are necessary not only for treatment but also for preventing biomechanical chain reactions. This chapter gives an overview of the epidemiology, diagnosis and treatment of foot pain and foot disorders caused by both local and generalized diseases.

The juvenile-onset spondyloarthritides: rationale for clinical evaluation

This chapter reviews the clinical events that occur in patients with juvenile-onset spondyloarthritides (SpA) with the purpose of developing core sets, domains and instruments to evaluate disease activity and disease damage. We discuss several aspects, from concept and classification to clinical features and instruments already in use for measuring adult-onset SpA and childhood arthritides. Similarly, comparisons between juvenile-onset SpA, its adult counterpart, and other forms of juvenile arthritis are made to consider the adaptation of existing instruments or to develop specific ones.