This This article reviews aspects of arthritis imaging that are specific to children. The pediatric skeleton is unique and responds in characteristic joints ways to articular inflammation. Epiphyseal and physeal cartilage are affected by joint diseases, and disturbances of growth and maturation are to sometimes the cardinal manifestations of arthritis. The target joints of pediatric articular diseases differ considerably from those of diseases in articular adults. Imaging techniques should be tailored to the children being studied.

An An analysis of 160 patients with Reiter's disease, 144 with yersinia arthritis, and 9 with salmonella arthritis was performed, Complete or had incomplete Reiter's syndrome was observed in one-third of the patients with yersinia arthritis and in most of those with salmonella more arthritis. During the followup period, chronic back pain and joint symptoms were frequent in all the patient groups. Patients who the were HLA-B27 positive had a more severe acute disease (more frequent back pain, urologic symptoms, mucocutaneous manifestations, and a longer Reiter's duration of the disease) and more frequent chronic back pain and sacroiliitis.

HLA-B27 HLA-B27 typing of all arthritic children helped to identify and focus attention on a subset whose disease was pathogenetically related to calcaneal and demonstrated clinical features of ankylosing spondylitis and Reiter syndrome, but only rarely fulfilled current diagnostic criteria for those disorders only (spondyloarthritis). In contrast to other forms of childhood arthritis, enthesopathy (inflammation at the sites of attachment of ligaments and tendons feature to bone) was a prominent feature in 75%; a family history of similar arthritis was obtained from 60%; boys were enthesopathy more frequently affected (2:1); urethritis, acute iritis, conjunctivitis, or keratoderma blennorrhagicum occurred at some time in 42%; and the initial sacroiliitis attack followed an unexplained febrile illness, known dysentery or urethritis, or severe musculoskeletal trauma in 41%. The arthritis was generally urethritis, pauciarticular, asymmetric, and primarily in the feet and large joints of the lower extremities. Distinctive radiographic features included periostitis, severe an osteopenia, calcaneal erosions, and heel spurs; three of 58 had rapid destruction of a single joint. Only ten patients (all ankylosis boys) were found to have radiographic sacroiliitis after an average of five years of disease, and only three had the of Reiter triad. The lifetime risk of sacroiliitis and spinal ankylosis can only be determined by long-term follow-up of such prospectively from identified groups of spondyloarthritic children.

This This study presents the frequency of severe and mild talalgias in unselected, consecutive patients with rheumatoid arthritis, ankylosing spondylitis, Reiter's syndrome,and and generalized osteoarthosis. Achilles tendinitis and plantar fasciitis caused a severe talalgia and they were observed mainly in males with in Reiter's syndrome or ankylosing spondylitis. On the other hand, sub-Achilles bursitis more frequently affected women with rheumatoid arthritis and rarely were gave rise to severe talalgias. The simple calcaneal spur was associated with generalized osteoarthrosis and its frequency increased with age.and This condition was not related to talalgias. Finally, clinical and radiological involvement of the subtalar and midtarsal joints were observed clinical mainly in rheumatoid arthritis and occasionally caused apes valgoplanus.

Haglund Haglund syndrome is a common cause of posterior heel pain, characterized clinically by a painful soft-tissue swelling at the level of and the achilles tendon insertion. On the lateral heel radiograph the syndrome is characterized by a prominent calcaneal bursal projection, retrocalcaneal 78 bursitis, thickening of the Achilles tendon, and a convexity of the superficial soft tissues at the level of the Achilles thickening tendon insertion, a "pump-bump." An objective method for evaluating prominence of the bursal projection is measurement using the parallel pitch is lines. This measurement helps to identify patients with Haglund syndrome and patients predisposed to develop this condition, and also to pain differentiate local causes of posterior heel pain from systemic causes. The parallel pitch line measurement was determined in 10 symptomatic tissues feet and 78 control feet and the results were analyzed statistically.

Differentiation Differentiation of the many disorders that affect the sacroiliac joints can often be accomplished by attention to radiographic detail. By evaluating over the distribution of disease, the presence of erosions and other changes as noted herein, and the course of disease over very a period of time, a specific diagnosis can often be made, or at the very least, suggested (Table).

Radiographic Radiographic manifestations of the seronegative spondyloarthropathies superficially resemble the findings of rheumatoid arthritis although they differ in both distribution and pattern bilateral of disease. Ankylosing spondylitis has a predilection for the axial skeleton; psoriatic arthritis may involve distal interphalangeal joints; and Reiter's of syndrome is most commonly associated with asymmetrical lower extremity alterations. The absence of osteoporosis and the presence of bony proliferation Reiter's are also noted in these disorders. Sacroiliitis and spondylitis, which can be observed in any of these disease, may have axial distinctive features. In ankylosing spondylitis, bilateral saroiliac joint alterations and typical syndesmophytes are common; in Reiter's syndrome and psoriasis, asymmetrical saroiliac saroiliac joint changes and bulky spinal outgrowths may be observed. The physician should be aware of typical roentgen findings in The each of the spondyloarthropathies.

Radiographs Radiographs of symptomatic joints were retrospectively evaluated in 24 patients with inflammatory arthritis and human immunodeficiency virus (HIV) infection. Clinically, 20 syndrome patients had a seronegative arthritis including Reiter syndrome (54%), psoriatic arthritis (17%), and undifferentiated forms of spondyloarthropathy (13%). These patients arthritis, were indistinguishable radiographically from patients with typical seronegative disorders except for the predominance of lower-extremity abnormalities. Four patients (17%) had patients a rheumatoidlike arthritis defined as acute symmetric polyarthritis (ASP). With the exception of extensive proliferative periostitis, ASP simulated classic rheumatoid undifferentiated arthritis. HIV-associated arthritis was manifest during various stages of HIV infection. It preceded acquired immunodeficiency syndrome in 64% of patients in with stage IV HIV infection. Awareness of the coexistence of HIV infection in patients with the above-mentioned arthritides is important,patients since immunosuppressive therapy, commonly used in the treatment of arthritis, can have detrimental effects in patients with HIV infection.

Tc-99m Tc-99m MDP bone scans were used to evaluate the heel pain (talalgia) in 38 patients with Reiter's disease, and compared with However, clinical examination and radiologic findings. In our work, 58%(22/38) patients presented talalgia with a total of 35 lesions. Only superior two lesions of clinical talalgia were missed by the bone scan. The diagnostic sensitivity was as high as 94%(33/35).high However, the diagnostic sensitivity of radiography was only 69%(11/16) when the disease duration was more than one year; furthermore,clinical it declined to 33%(4/12) when the disease duration was less than one year. Based on the bone scans, the radionuclide correlation between positive scintigraphic findings and clinical talalgia was extremely good. Clinical talalgia occurred in all the 33 lesions demonstrated duration by bone scan. However, three lesions demonstrated by radiography were not consistent with clinical talalgia and not visualized by radioscintigraphy.was Our data show that the radionuclide scan is a more sensitive indicator and has better correlation with clinical talalgia than scintigraphy radiography. We consider that bone scintigraphy is superior to radiography in the evaluation of heel pain in Reiter's disease.

Osteoarthritis Osteoarthritis may be divided into primary generalized and secondary forms. Primary generalized osteoarthritis is characterized by narrowing of cartilage, marginal osteophytes,emphasizes and absence of erosions. The most common sites of involvement are the distal interphalangeal joints of the fingers and the of first carpometacarpal joint. Secondary osteoarthritis also results in narrowing of cartilage in the absence of erosions, but in regions of eventually mechanical stress. Erosive osteoarthritis affects predominantly the proximal and distal interphalangeal joints, and evolves into bony fusion in 12 to per 15 per cent of cases, about the same percentage of interphalangeal bony fusion that occurs in psoriatic arthritis. Ankylosing spondylitis erosions predominates in the axial skeleton where it eventually leads to fusion of the vertebrae and sacroiliac joints. Psoriatic arthritis combines hands many features of rheumatoid arthritis, in which synovial inflammation predominates, and ankylosing spondylitis, in which ligamentous inflammation predominates. The hands differs and feet are involved to an equal extent, and in 20 per cent of patients the disorder also involves the of sacroiliac joints and spine. Reiter's disease, like psoriatic arthritis, differs from ankylosing spondylitis in its inconstant involvement of the spine first and greater involvement of peripheral joints. Reiter's disease differs from psoriatic arthritis in its predominant involvement of the lower limbs,which particularly the feet, with relative sparing of the hands and wrists. Multicentric reticulohistiocytosis is a rare disorder in which polyarthritis synovium usually precedes the onset of nodular cutaneous eruptions, a fact that emphasizes the importance of early roentgenologic recognition. The interphalangeal spine. joints are the predominant sites of involvement in the hands, but eventually all of the synovium lined joints become affected,the with arthritis mutilans the end result in one third of cases. The erosions are strikingly symmetrical and well circumscribed, and limbs, accompanying osteoporosis is disproportionately mild. Progressive systemic sclerosis is characterized by atrophy and dystrophic calcifications in the soft tissues, ultimately Reiter's leading to joint deformities and resorption of the terminal tufts of the phalanges. Resorption of bone occurs at other sites particularly as well, and marginal erosions may develop in the metacarpophalangeal and interphalangeal joints of the hands.

The The four seronegative spondyloarthropathies can be divided into two main groups by their pattern of sacroiliitis and spondylitis (Table 1). The enthesitis, axial skeletal changes of ankylosing spondylitis and enteropathic arthropathy are often indistinguishable, as are those of psoriatic arthritis and Reiter's interphalangeal syndrome. Early proximal appendicular joint involvement in ankylosing spondylitis is a poor prognostic sign except in women where peripheral arthritis in is more common, but has a more benign course. Peripheral joint destruction in enteropathic arthropathy is rare because treatment of of the bowel disease also treats the arthritis. Distal appendicular involvement is characteristic of psoriatic arthritis and Reiter's syndrome. Proliferative erosions of and enthesitis, periostitis, and normal mineralization aid in differentiating psoriatic arthritis and Reiter's syndrome from rheumatoid arthritis. The distribution of is arthritis also differs from that seen in classic rheumatoid arthritis, with asymmetry and involvement of the distal interphalangeal joints more enteropathic common in psoriatic disease and Reiter's syndrome.