A review of radiographic evaluation of rheumatoid arthritis is given. Standard reference films are introduced for evaluation of rheumatoid arthritis and related conditions in the extremity joints. In this system, numerical evaluation of arthritis is given for individual joints in a patient.

Objective. To explore early changes and predictors of bone mass in children with juvenile idiopathic arthritis (JIA) in order to identify patients who will develop bone mass reductions.Methods. We conducted a prospective cohort study of 108 children with early JIA (ages 6-18 years; mean disease duration 19.3 months) who were individually matched with 108 healthy children for age, sex, race, and county of residence. Bone mass and changes in total body, spine, femur, and forearm bone mineral density and bone mineral content (BMC), body composition, growth, and biochemical parameters of bone turnover were examined at baseline and at followup a mean of 24 months later. Low bone mass was defined as a Z score >1 SD below the reference population.Results. Of the 200 children evaluated at followup, the 100 healthy children had greater gains in total body BMC (P ‫؍‬ 0.035), distal radius BMC (P < 0.001), and total body lean mass (P < 0.001) than did the 100 JIA patients. Low or very low total body BMC was observed in 24% of the patients and 12% of the healthy children. Bone formation, bone resorption, and weight-bearing activities were reduced in the patients compared with the healthy children. Multiple regression analysis showed that in patients with JIA, serum bonespecific alkaline phosphatase, serum C-telopeptide of type I collagen, and weight-bearing activities were independent predictors of changes in total body BMC. Total body BMC was lower in patients with polyarticular onset than in those with oligoarticular disease onset.Conclusion. Patients with JIA have moderate reductions in bone mass gains, bone turnover, and total body lean mass early in the disease course.

Objective. To determine the frequency of low bone mineral content (BMC) and low bone mineral density (BMD) as long-term complications in adolescents with early-onset juvenile idiopathic arthritis (JIA), and to identify disease variables, patient characteristics, and biochemical bone markers related to low bone mass.Methods. One hundred five (87%) of 121 adolescent patients with early-onset JIA (ages 13-19 years, 80 girls and 25 boys, mean age at onset of JIA 2.8 years), from a cohort first admitted to the hospital between 1980 and 1985, were assessed after a mean disease duration of 14.2 years. BMC and BMD of the total body, the lumbar spine at L2-L4, and the femoral neck were measured by dual-energy x-ray absorptiometry. Ageand sex-specific reference values from a pooled, healthy reference population were used to calculate Z scores. Low bone mass was defined as a Z score less than ؊1 SD.Results. Among the 103 adolescent JIA patients who underwent total-body imaging, 41% had low totalbody BMC and 34% had low total-body BMD. Compared with adolescent JIA patients who had normal total-body BMC, those with low BMC had lower mean weight (P < 0.001), height (P < 0.001), lean mass (P < 0.001), and remission rates (P ‫؍‬ 0.016), had longer duration of active disease (P ‫؍‬ 0.013), had higher numbers of active and mobility-restricted joints (P < 0.001 and P ‫؍‬ 0.001, respectively), had more disability (P ‫؍‬ 0.011), had higher frequencies of joint erosions (P < 0.001), and had higher erythrocyte sedimentation rates (P ‫؍‬ 0.033). In multiple linear regression analyses of total-body BMC, 88% of the variance was explained by the duration of active disease, the number of joints with restricted mobility, the bone area, urinary deoxypyridinoline values, age, weight, and height.Conclusion. Forty-one percent of the adolescents with early-onset JIA had low bone mass >11 years after disease onset. The development of low total-body BMC was related to the duration of active disease, disease severity, measures of bone resorption, weight, and height.Osteoporosis is a public health problem worldwide. An important determinant of osteoporosis and future fracture risk is the peak bone mass achieved during the period of skeletal growth. Skeletal maturation in children is dependent on the rate of bone formation exceeding the rate of bone resorption. Peak bone mass is defined as the bone mass present at the end of skeletal maturation, which occurs after age 20 years. If a sound foundation for peak bone mass, which is partly genetically determined, is not established during the second decade of life, the young adult will experience osteopenia and an increased fracture risk (1). Children with a chronic illness such as arthritis are at risk of developing osteopenia that is influenced by (in addition to heredity and hormones) inflammation, medication, nutrition, and physical inactivity.

The diagnostic value of typical symptoms and abnormal chest signs for pneumonia have been evaluated against a radiographic reference standard in 402 adult patients with respiratory tract infection in general practice. Pneumonia was diagnosed in 20 patients by a positive chest radiograph. The doctors diagnosed pneumonia in seven of these on the basis of history and physical examination alone, and in addition in 22 patients with normal radiographs. The diagnostic value of the typical symptoms cough, chest pain, and dyspnoea, reported by the patients on a questionnaire, increased with increasing intensity of the symptoms, and both "very annoying lateral chest pain" and "very annoying dyspnoea" had likelihood ratios (LR) between 4 and 5. The LR of crackles was 3.7. When evaluated against the doctor's clinical diagnosis of pneumonia as reference standard, crackles achieved an LR of 14.8, while the typical symptoms achieved lower LRs than when evaluated against the radiographic reference standard. These discrepancies, which were confirmed by logistic regression, indicate that crackles and other abnormal chest findings are interpreted too frequently as features of pneumonia and that the importance of typical symptoms is underestimated in the diagnosis of pneumonia.

In the current study, radiographically evident sacroiliitis had developed in 6% of JIA patients after a median disease duration of 14.9 years. HLA-B27, absence of DPB1*02, late onset of disease, and early hip involvement were predictors of sacroiliitis.