Providing the techniques for lower limb reconstructive surgery to help patients regain more normal bipedal walking not only represents a surgical aspect of RA treatment, but it is also contributes to readjusting the life planning of RA patients in an era of longevity. In this perspective, it is considered to be important that orthopedic surgeon, fully understanding the pathology of RA and the issues faced by RA patients. Furthermore, it is essential to always keep collaboration with other departments（or multiple disciplines）in mind and to adopt a multidisciplinary approach, which represents the ideal way to address RA-related foot problems.

Autoinflammatory syndromes are diseases characterized by recurrent systemic inflammation. Genetic mutations cause abnormalities in the proteins encoded by these syndromes, leading to increased cytokine production, primarily through modulation of innate immunity. While once considered a foreign disease, they have become increasingly recognized by clinicians in Japan. In recent years, disease genes have been identified almost annually, and new autoinflammatory syndromes have been reported. As pathogenesis has been elucidated, they have been broadly classified into three categories: inflammasomepathies, interferonopathies, and relopathies. Acquired autoinflammatory syndromes, in which clinical symptoms are manifested by acquired genetic mutations, have also attracted attention. Genetic testing for autoinflammatory syndromes is now available under health insurance coverage, making diagnosis easier in patients with fever of unknown origin and periodic fever. Because many inflammatory cytokines are detected in serum in autoinflammatory syndromes, anti-cytokine therapy is the primary treatment. Among these, anti-IL-1 agents are particularly effective compared to other inflammatory diseases. Current challenges with autoinflammatory syndromes include the difficulty of diagnosing familial Mediterranean fever and the need for a change in awareness of transitional care.

Familial Mediterranean Fever（FMF）is a representative autoinflammatory disease caused by variants in the MEFV gene, characterized by recurrent fever and serositis. Although traditionally regarded as highly prevalent among populations in the Mediterranean basin, advances in genetic testing and the accumulation of clinical reports have led to increasing recognition of FMF in non-Mediterranean regions, including Japan. The pathogenesis of FMF is driven by dysregulated inflammatory responses via the Pyrin inflammasome, leading to excessive production of IL-1β and IL-18, along with secondary release of other proinflammatory cytokines. Compared with typical cases in the Middle East, Japanese patients exhibit a lower frequency of exon 10 mutations and a higher prevalence of low-penetrance variants such as E148Q and P369S/R408Q. For diagnosis, repeated febrile episodes and characteristic clinical features, in combination with MEFV genetic analysis and evaluation of colchicine responsiveness, are crucial. Colchicine is established as the first-line therapy, effective in both preventing attacks and reducing the long-term risk of AA amyloidosis. However, a subset of patients experience intolerance or insufficient response, for whom IL-1 inhibitors have shown clinical benefit. In recent years, treatment algorithms based on this evidence have been proposed, highlighting stepwise therapeutic approaches and underscoring the importance of personalized medicine tailored to each patient’s genetic background and clinical phenotype.

Periodic fever syndromes（PFSs）are autoinflammatory disorders marked by recurrent systemic inflammation. This review covers hereditary syndromes—cryopyrin-associated periodic syndromes（CAPS）, tumor necrosis factor receptor–associated periodic syndrome（TRAPS）, and the nonhereditary PFAPA syndrome. In CAPS, gain-of-function NLRP3 mutations cause inflammasome hyperactivation and IL-1β overproduction; advances in detecting somatic mosaicism have refined diagnosis and underscore early IL-1 blockade to prevent irreversible organ damage. TRAPS stems from TNFRSF1A mutations with variable penetrance, requiring personalized approaches—TNF inhibitors, IL-1 antagonists, or combinations—to maintain disease control and reduce amyloidosis risk. PFAPA is diagnosed clinically by periodic fevers with mucosal and lymphoid involvement; while corticosteroids and tonsillectomy achieve high remission in children, adult-onset and refractory cases challenge diagnosis and management, with emerging reports on IL-1 inhibition. Japanese cohort data highlight the critical roles of timely diagnosis, tailored therapies, and multidisciplinary collaboration in improving long-term outcomes for PFS patients.

Autoinflammatory syndromes are disorders caused by dysregulation of the innate immune system, often mimicking rheumatic diseases such as Behçet’s disease and vasculitis. Differentiating autoinflammatory syndromes from rheumatic diseases is important in clinical practice. This review highlights key autoinflammatory diseases that resemble rheumatic diseases, including A20 haploinsufficiency, PAPA syndrome, ADA2 deficiency, and NLRC4-associated conditions. These disorders present with overlapping symptoms such as recurrent fever, skin lesions, arthritis, and vasculitis, complicating diagnosis. Advances in genetic testing have improved identification and enabled targeted treatments like IL-1 and TNF inhibitors. Some autoinflammatory diseases result from somatic mutations, causing “acquired” autoinflammatory diseases. Understanding autoinflammatory syndromes and rheumatic diseases is essential for accurate diagnosis and effective therapy. Ongoing research will continue to clarify disease mechanisms and expand treatment options.

Adult-onset Still’s disease（AOSD）is a systemic inflammatory disorder characterized by the triad of spiking fever, evanescent rash, and arthritis. It is currently regarded as part of the broader spectrum of Still’s disease, together with systemic juvenile idiopathic arthritis, reflecting their shared clinical and immunopathological features. In addition to the three cardinal manifestations, patients may present with sore throat, myalgia, lymphadenopathy, hepatosplenomegaly, serositis, and occasionally severe pulmonary involvement. Laboratory abnormalities typically include marked systemic inflammation, neutrophilic leukocytosis, liver dysfunction, hyperferritinemia, and elevated interleukin-18 levels. Among disease complications, macrophage activation syndrome（MAS）is of particular importance because of its potentially life-threatening nature and the need for prompt recognition and intervention. Diagnosis is based on the combination of characteristic clinical and laboratory findings and the careful exclusion of infections, malignancies, and other rheumatic diseases, with the Yamaguchi criteria still widely used in clinical practice. Glucocorticoids have long been the cornerstone of treatment, while methotrexate and calcineurin inhibitors have been used in refractory cases. More recently, biologic agents targeting interleukin-6 and interleukin-1, including tocilizumab and canakinumab, have expanded therapeutic options. This review summarizes the clinical manifestations, laboratory findings, differential diagnosis, and classification criteria of Still’s disease, and discusses recent advances, including standardized diagnostic processes to reduce diagnostic delay, Treat-to-Target strategies, and the early identification and treatment of MAS.

VEXAS syndrome is an autoinflammatory disorder characterized by systemic inflammation and hematologic abnormalities caused by somatic variants in the UBA1 gene. Since the initial report in 2020, many studies and case reports from around the world have clarified its clinical features, pathogenesis, therapeutic response, and prognosis. Currently, the diagnosis of VEXAS syndrome is confirmed by identifying known pathogenic UBA1 variants through genetic analysis. Determining which patients should undergo genetic testing is critically important.

Recent international guidance statements recommend considering VEXAS syndrome in middle-aged males with persistent inflammation and evaluating characteristic clinical symptoms and hematologic abnormalities with VEXAS syndrome. When performing UBA1 gene analysis, clinicians should recognize the coverage and sensitivity of each assay method to ensure proper diagnosis. For treatment, glucocorticoids are primarily administered, but dose reduction is often difficult. The addition of IL-6 inhibitors, JAK inhibitors, or IL-1 inhibitors may provide glucocorticoids sparing effects, although these effects are limited. Azacitidine and hematopoietic stem cell transplantation have shown potential benefits in several cases, however, disease-specific therapeutic strategies are still urgently needed.

Objective: To clarify the influence of novel coronavirus disease（COVID-19）on the number of outpatients with rheumatic diseases at the Ishii Clinic in Saitama prefecture.

Patients and methods: The number of patients with rheumatic diseases at the monthly outpatient ward before and during the COVID-19 pandemic was compared（92 patients（male 33, female 59）, mean age 63.2±13.3 years old vs 104 patients（male 41, female 63, mean age 63.7±14.0 years old）. In addition, the number of patients with rheumatic diseases was compared with that of orthopaedic patients.

Results: The number of patients with rheumatic diseases before COVID-19（2019）was 498 but this number slightly increased during the COVID-19 pandemic（2020, n=523, 5% increment）. Even during the declared emergency period, the numbers of the patients did not change. However, the number of patients in the orthopaedic outpatient ward at the Ishii Clinic before COVID-19（2019, n= 82,457）decreased the year after the COVID-19 pandemic was declared（2020, n=80,244, 3% decrease）especially during the declared emergency period in Japan.

Conclusion: The number of the orthopaedic patients decreased during the COVID-19 period probably due to the fear for the infection of COVID-19 or decrease in the number of trauma patients due to the lowered physical activity, but the COVID-19 pandemic did not influence the number of patients with rheumatic diseases visiting the outpatient ward. The specific characteristics of rheumatic diseases and the relationship between patients and either rheumatologists or other medical staff may prevent treatment discontinuation.

Mirogabalin, a drug used to treat peripheral neuropathic pain, was approved in Japan in 2019. However, its dosage and administration in elderly individuals are debatable. We aimed to retrospectively investigate the efficacy and safety of low-dose mirogabalin treatment as add-on therapy for musculoskeletal disorders in patients aged ≥ 80 years. Five patients aged ≥ 80 years who received mirogabalin as add-on therapy to insufficient pre-existing analgesic treatment were included. The primary diseases treated were lumbar spinal stenosis（n=3）and knee osteoarthritis（n=1）. The median dose of mirogabalin was 2.5mg twice daily（5mg/day）. The median treatment duration was 12（range 9-19）months. The median numeric pain rating scale（NPRS）score improved from 8（range, 7-9）points before treatment to 3（range, 2-5）points after treatment. The median reduction in the NPRS score was 5（range, 3-6）points. A mild decrease in eGFR was observed in one of three patients with available follow-up data. The median time to response was 1（range, 1-3）months. No adverse effects were observed. Overall, low-dose mirogabalin as add-on therapy may be both effective and safe in the management of chronic pain associated with musculoskeletal conditions, particularly lumbar spinal stenosis and knee osteoarthritis, in individuals aged ≥ 80 years.