CLINICAL PRACTICE ARTICLE
Spectrum of Joint Deformities in Children with Juvenile Idiopathic Arthritis
Samia Naz1, Misbah Asif2, Farrah Naz1, Hina Farooq3 and Muhammad Haroon Hamid1
ABSTRACT
Objective: To determine the frequency and types of joint deformities in children with juvenile idiopathic arthritis and their association with clinical parameters and rheumatoid factor. Study Design: Cross-sectional study. Place and Duration of Study: Rheumatology Outpatient Clinic, the Children's Hospital and the Institute of Child Health, Lahore, from September 2014 to February 2015. Methodology: All patients of both genders of less than 16 years of age, who fulfilled the International League of Association for Rheumatology (ILAR) criteria for Juvenile Idiopathic Arthritis (JIA), were enrolled in this study. Their demographic data, duration of disease at the time of presentation, types of JIA, various joint deformities and rheumatoid factor (RF) were documented. Statistical analysis of data was done on SPSS version 16. Chi-square test was applied to determine the association of clinical deformity with age of patients, disease duration at presentation, types of JIA and RF. Results: Out of 70 patients enrolled during the study period, 51.4% were boys with mean age at presentation being 9.44 ±3.89 years (2-7 years) and median duration of disease being 24 months (interquartile range 42 months). Forty patients (57.1%) had joint deformities. Most common joints involved were hand (50%), wrist (50%), and knee (35.7%). The common types of joint deformities were boutonniere deformity (28.6%), ulnar deviation of wrist (28.6%), fixed flexion deformity of wrist (22.9%), and knee (31.4%). The most common type of JIA was polyarthritis RF negative with or without deformity. There was a strong association of deformities with older age of patients at presentation (p=0.036), longer duration of disease at presentation (p=0.028), polyarthritis (RF seronegative / seropositive) (p=0.013), and seropositivity (p=0.04). Conclusion: More than 50% patients with JIA have joint deformities. Joint deformities are more likely to be seen in children with long-standing disease, those with polyarthritis JIA and seropositive patients. Key Words: Juvenile idiopathic arthritis. JIA. Joint deformity. Polyarthritis. Rheumatoid factor (RF).
INTRODUCTION
Juvenile idiopathic arthritis (JIA) is the leading cause of autoimmune arthritis in children and adolescents causing clinical deformities. Epidemiological studies have reported a burden of 0.07-4.01 per 1000 children.1 The true incidence and prevalence in our region is not known. There are substantial geographic, and ethnic differences are present regarding the frequencies of different types, age at onset, and immunological markers.1-3 JIA has different subtypes with varied morbidity. It is a significant cause of short- and long-term disability in children and adolescents.1,4 The most serious complication is the development of joint deformities. Common deformities of hand and wrist joints include 1 2 3
Department of Paediatric Medicine, Children's Hospital and The Institute of Child Health, Lahore. Department of Physiotherapy, Pakistan Society for the Rehabilitation of Disabled, Lahore. Department of Occupational Therapy, Autism Resource Centre, Lahore.
Correspondence: Dr. Samia Naz, Assistant Professor of Paediatric Medicine, Children's Hospital and The Institute of Child Health, Lahore. E-mail:
[email protected] Received: March 06, 2017; Accepted: March 27, 2018. 470
spindling of fingers, swan neck deformity, boutonniere deformity, Z-deformity of thumb, subluxation of metacarpophalangeal joints, ulnar deviation of wrist, radial deviation of fingers, and flexion/fixed flexion deformity of wrist. Feet and ankle deformities are lateral deviation of big toe (hallux valgus), subluxation of metatarsophalangeal joints and valgus deformity of ankle. Knee deformities in JIA are valgus and varus deformities and flexion/fixed flexion deformity. Atlantoaxial subluxtion is the deformity of cervical spine. Other orthopedic complications include leg length discrepancy and growth delay.5 JIA is a chronic disease causing deformities; and timely diagnosis and prompt multi-disciplinary management is necessary to prevent complications. Various studies have shown different early predictors of poor outcome including female gender, older age at onset, longer duration of disease before referral, early involvement of small joints of hands and feet, rapid appearance of erosions, unremitting inflammatory activity, RF seropositivity, and subcutaneous nodules.6 There is paucity of reported literature from Pakistan on this deforming chronic ailment in children, especially in the context of spectrum of deformities and its possible associations. The objective of this study was to determine the frequencies and types of joint deformities in juvenile
Journal of the College of Physicians and Surgeons Pakistan 2018, Vol. 28 (6): 470-473
Joint deformities in juvenile idiopathic arthritis
idiopathic arthritis and their association with clinical parameters and rheumatoid factor.
METHODOLOGY
This cross-sectional analytical study was carried out at Rheumatology Outpatient Clinic, The Children's Hospital and The Institute of Child Health, Lahore, from September 2014 to February 2015. Informed consent was obtained from all parents or children. All patients seen in clinic during the study period, of both genders of less than 16 years of age who fulfilled the International League of Association for Rheumatology (ILAR) criteria for Juvenile Idiopathic Arthritis (JIA),5 were enrolled in this study. Their demographic data, duration of disease at presentation, and types of arthritis per ILAR criteria were recorded in a pretested proforma at their first clinical visit. The ILAR criteria included the following: 1. Systemic-onset JIA, arthritis in >1 joints with or preceded by fever of at least 2 weeks in duration that is documented to be daily ("quotidian") for at least 3 days and accompanied by >1 of the following: (a) evanescent (nonfixed) erythematous rash, (b) generalised lymph node enlargement, (c) hepatomegaly or splenomegaly or both, and (d) serositis.
2. Oligoarticular JIA, arthritis affecting 1-4 joints during the initial six months of disease. Two subcategories are recognised as persistent oligoarthritis-affecting >4 joints throughout the disease course, and extended oligoarthritis-affecting >4 joints after the first 6 months of disease. 3. Rheumatoid factor negative polyarthritis, arthritis affecting >5 joints during the initial six months of disease and a test for RF is negative. 4. Rheumatoid factor positive polyarthritis, arthritis affecting >5 joints during the initial six month of disease and 2 or more tests for RF at least 3 months apart during the first 6 months of disease are positive. 5. Psoriatic arthritis, arthritis and psoriasis, or arthritis and at least 2 of the following: (a) dactylitis, (b) nail pitting and onycholysis, (c) psoriasis in a first-degree relative.
6. Enthesitis-related arthritis, arthritis and enthesitis, or arthritis or enthesitis with at least two of the following: a. presence of or a history of sacroiliac joint tenderness and/or inflammatory lumbosacral pain; b. presence of HLA-B27 antigen; c. onset of arthritis in a male over 6 years of age; d. acute (symptomatic) anterior uveitis; and e. history of ankylosing spondylitis, enthesitis-related arthritis, sacroiliitis with inflammatory bowel disease, Reiter's syndrome or acute anterior uveitis in a firstdegree relative. 7. Undifferentiated arthritis is arthritis that fulfils criteria in no category or in >2 of the above categories.5
Patients were thoroughly examined for various deformities of joints. Deformities involving wrists, elbows, knees,
and ankles were taken as one, either single or both joints were involved respectively. Upper limb deformities noted included spindling of fingers, swan neck deformity, boutonniere deformity, Z-deformity of thumb, ulnar deviation of wrist, radial deviation of finger, and flexion/fixed flexion deformity of elbow joint. Lower limb deformities noted included flexion/fixed flexion deformity of knees, valgus deformity of knees and ankles, varus deformity of knees, lateral deviation of toes, and outward deviation of feet. Rheumatoid factor was determined by indirect haemagglutination method. Statistical analysis was performed by statistical package for social sciences (SPSS) version 16.0. Mean and median were determined for quantitative variables. Frequencies and percentages were used to describe distribution of age and gender in different groups. Frequency of deformities in various joints of body is described as pie chart. Various types of deformities in upper and lower limbs are shown as bar charts. Chisquare test was performed to determine the relationship of demographic data and rheumatoid factor with joint deformity. P-value of
