Rheumatoid Arthritis

Rheumatoid arthritis is a fairly common systemic disease of multifarious and obscure etiologies, affecting primarily the synovial membranes of the joints in the appendicular and axial skeleton. It has a notorious predilection for the small joints of the hands and feet although the large joints of the wrists, knees, elbows, shoulders, and sternum are not exempted. The involvement is typically polyarticular and symmetrical. In the spine, the cervical vertebrae, particularly the atlantoaxial joint, are most commonly involved, and cervical involvement may or may not be accompanied by appendicular arthritis (Bland 1967). The prevalence rate estimated using the 1958 criteria of the American Rheumatism Association for definite rheumatoid arthritis varies from 0.3% to 1.5% (Wolfe 1968), and limited population studies performed in Europe and North America have indicated the incidence to range from 1% to 3%. A recent limited population study performed in Seoul has shown a prevalence rate of 1.5% (Bae SC, 2005, personal communication). Women are affected two to three times more frequently than men. Adults in any age may be affected, with the highest incidence occurring between the fifth and sixth decades of life.

The clinical diagnosis is based on seven criteria recommended by the American Rheumatism Association: (1) morning stiffness, (2) arthritis of three or more joints, (3) arthritis of hand joints, (4) symmetrical arthritis, (5) rheumatoid nodules, (6) serum rheumatoid factor, and (7) radiological alterations including erosions and/or periarticular osteoporosis in the hand and wrist joints (Arnett et al. 1988). Clinically, the involvement of the small joints in the hands and feet is essential for diagnosis. The next most commonly involved sites are the cervical spine, shoulders, elbows, wrists, hips, knees, and ankles. The sternum, temporoman-dibular joints, sacroiliac joints, and symphysis pubis are less regularly affected.

Pathology and Laboratory Tests Rheumatoid arthritis initiates as synovitis, which is pathologically characterized by edema, hyperemia, and exudation (Gibson 1955). Prominent cellular infiltration and proliferation of granulation tissue follow. With the progression of disease the synovia become thickened with the enlargement of villi, resulting in pannus formation in the perichondriums. By the action of hydrolytic enzymes, pannus erodes and tears the articular cartilage and subchondral bone at the unprotected marginal zones, and eventually the periarticular ligaments and tendons. In the late stage, disorganized articulations are replaced by fibrous and osseous ankylosis.

A number of laboratory tests are available for the clinical diagnosis of this disease. Accelerated erythrocyte sedimentation rate and increased C-reactive protein and rheumatoid factors are more reliable. The quantitative data are known to be well correlated with the clinical activities of rheumatoid arthritis.

Radiographic Manifestations Radiographic features vary according to the disease stage. In the early stage periarticular soft-tissue swelling and articular widening are observed, reflecting synovial edema and effusion. Periarticular os-teopenia is an important finding, which is not regularlyobserved in osteoarthritis (Fig. 10.1 A). Erosion and destruction of the articular carti-

Periarticular Osteoporosis

Fig. 10.1A, B Marked periarticular osteoporosis and symmetrical articular narrowing in rheumatoid arthritis. A Dorsoventral radiograph of the right hand in a 23-year-old woman with acutely exacerbating rheumatoid arthritis shows marked porosis in the periarticular bones of the proximal interphalangeal joints and metacarpophalan-geal joints (arrowheads). B Anteroposterior radiograph of the right hip in a 44-year-old man with rheumatoid arthritis reveals concentric narrowing of the joint with axial shift of the femoral head (arrow). The regional bones are porotic and the articular capsule is distended (arrowheads)

Images Whole Body Arthritis
Fig. 10.2 Whole-body survey scintigraphy in polyarthritis. Anterior whole-body scintigraph delineates the classic, symmetrical, polyarticular nature of rheumatoid arthritis. All of the large and small joints in the upper and lower extremities are involved (arrowheads)

Fig. 10.1A, B Marked periarticular osteoporosis and symmetrical articular narrowing in rheumatoid arthritis. A Dorsoventral radiograph of the right hand in a 23-year-old woman with acutely exacerbating rheumatoid arthritis shows marked porosis in the periarticular bones of the proximal interphalangeal joints and metacarpophalan-geal joints (arrowheads). B Anteroposterior radiograph of the right hip in a 44-year-old man with rheumatoid arthritis reveals concentric narrowing of the joint with axial shift of the femoral head (arrow). The regional bones are porotic and the articular capsule is distended (arrowheads)

lage follow with resultant articular narrowing, which is typically concentric and symmetrical (Fig. 10.1B) as opposed to asymmetrical narrowing in osteoarthritis (Fig. 9.10). Erosion and destruction occur in the periphery and center of joints, but tend to more severely involve the peripheral bones that are not protected by cartilage (Fletcher and Rowly 1952). The subchondral bones exposed to pannus after cartilage disintegration are readily eroded and

Polyarticular Osteoarthritis

Fig. 10.3 Symmetrical, polyarticular tracer uptake in wheelchair-bound poliomyelitis patient. Anterior whole-body scintigraph in a 35-year-old polio patient confined to a wheelchair (affected at the age of 3 years) with sinewy arms and bust and atrophic lower limbs reveals increased tracer uptake in all extremity joints, strongly mimicking symmetrical, polyarticular uptake pattern of rheumatoid arthritis (arrows). Tracer accumulations in the upper limb joints are generally more intense and are attributable to the active, muscular exercise of propelling the wheelchair, whereas those in the lower limb joints are less intense and well attributable to the longstanding disuse in this polio patient. Radiographic studies confirmed the skeletal hypertrophy in the upper limbs and atrophy in the lower limbs (not shown here)

Fig. 10.3 Symmetrical, polyarticular tracer uptake in wheelchair-bound poliomyelitis patient. Anterior whole-body scintigraph in a 35-year-old polio patient confined to a wheelchair (affected at the age of 3 years) with sinewy arms and bust and atrophic lower limbs reveals increased tracer uptake in all extremity joints, strongly mimicking symmetrical, polyarticular uptake pattern of rheumatoid arthritis (arrows). Tracer accumulations in the upper limb joints are generally more intense and are attributable to the active, muscular exercise of propelling the wheelchair, whereas those in the lower limb joints are less intense and well attributable to the longstanding disuse in this polio patient. Radiographic studies confirmed the skeletal hypertrophy in the upper limbs and atrophy in the lower limbs (not shown here)

broken, and undergo cystic change. In the late stage the diseased joints are ankylosed with angulation, subluxation, and even dislocation.

Bone Scintigraphic Manifestations 99mTc-MDP bone scintigraphy is the method of choice for the study of rheumatoid arthritis because it can provide not only holistic information on symmetrical polyarthritic involvement by whole-body scanning but can also show the individual articular changes in great detail by pinhole scanning. Recently, the scintigraphic imaging techniques have been worked out in the form of guidelines (Sandrock et al. 2003).

The whole-body scan reveals increased uptake in all or many of the joints in the extremities (Fig. 10.2). Characteristically, the lesions are polyarticular and symmetrical on both sides of the body with the involvement of the small joints in the hands and feet. The highresolution spot view or pinhole scan reveals further information, which is often specific. It is worth mentioning that rheumatoid polyarthritis may be strongly simulated on the whole-body scan by increased articular uptake in bed-ridden patients or those on crutches or in a wheelchair due to disuse or excessive use of the upper and lower limbs (Fig. 10.3).

On the other hand, pinhole scintigraphy in early rheumatoid arthritis reveals tracer uptake in the entire synovial cavity of the affected joints, denoting synovitis (Fig. 10.4A). The finding is similar to the "wrapped bone" sign of sympathetic synovitis (Fig. 8.5) or infective synovitis (Fig. 8.14). The articular space at this stage may be widened or unchanged. Periarti-cular osteopenia is clearly indicated by intense tracer uptake in the bones about the joints (Fig. 10.5). With the progress of the disease process articular cartilages and subchondral bones become disintegrated, resulting in articular narrowing. Rheumatoid erosions in the periarticular bones are shown as patchy or segmental areas of prominent uptake surrounded by a less intense uptake zone. The intensified uptake in the erosions is readily visualized in a large joint occasionally even with demonstration of inflamed para-articular tendons on the pinhole scan (Fig. 10.6). Bony ankylosis, the ultimate outcome of pannus and bone erosions, is indicated by tracer uptake of various intensities according to the age of ankylosis: mar-

Rheumatoid Arthritis Pannus

Fig. 10.4A, B Diffuse tracer uptake in the whole periarticular bones, producing a "wrapped bone" appearance in acute rheumatoid synovitis. A Anterior pinhole scinti-graph of the left knee in an 18-year-old man shows generalized, linear tracer uptake in all periarticular bones (arrowheads) including the patella (P). The joint space is somewhat widened. B Anteroposterior radiograph shows periarticular soft-tissue swelling (arrows) and porosis with pencil-line bone profile (arrowheads)

Rheumatoid Arthritis Stages

Fig. 10.5 Intense tracer uptake localized in the periarticular osteoporosis in rheumatoid arthritis. Dorsal pinhole scintigraph of the right hand with rheumatoid arthritis (the same patient as in Fig. 10.1A) shows intense tracer uptake localized in the bones about the metacarpophalangeal joints (arrows). Rapid diminution of bone size and tracer uptake in the periphery of the image is due to the characteristics of the pinhole geometry and the inverse square law, respectively. Note close correlation between the scintigraphic and radiographic findings

Fig. 10.5 Intense tracer uptake localized in the periarticular osteoporosis in rheumatoid arthritis. Dorsal pinhole scintigraph of the right hand with rheumatoid arthritis (the same patient as in Fig. 10.1A) shows intense tracer uptake localized in the bones about the metacarpophalangeal joints (arrows). Rapid diminution of bone size and tracer uptake in the periphery of the image is due to the characteristics of the pinhole geometry and the inverse square law, respectively. Note close correlation between the scintigraphic and radiographic findings

Fig. 10.4A, B Diffuse tracer uptake in the whole periarticular bones, producing a "wrapped bone" appearance in acute rheumatoid synovitis. A Anterior pinhole scinti-graph of the left knee in an 18-year-old man shows generalized, linear tracer uptake in all periarticular bones (arrowheads) including the patella (P). The joint space is somewhat widened. B Anteroposterior radiograph shows periarticular soft-tissue swelling (arrows) and porosis with pencil-line bone profile (arrowheads)

ked uptake in the active stage and mild uptake in the quiescent stage (Fig. 10.7). The traumati-zation or subluxation of an ankylosed joint results in intense tracer accumulation.

Nuclear angiography is very useful for dynamic assessment of vascular change that sensitively reflects the disease activity of rheumatoid arthritis (Hopfner et al. 2002, 2004) (Fig. 10.8). Recently, molecular nuclear imaging has also been added as a new diagnostic method in rheumatoid arthritis. The radiopharmaceuti-cals used for this include 99mTc-anti-E-selectin antibodies, 99mTc-IgG, radiolabeled cytokines, and somatostatin receptor. In addition, 18F-FDG PET has been introduced as a novel imaging modality in rheumatoid arthritis (Beckers et al. 2004) (Fig. 10.9).

Rheumatoid Arthritis Stages

Fig. 10.6 Segmental or patchy tracer uptake in bone erosions and "faint" tracer uptake in tenosynovitis in rheumatoid arthritis. Anterior pinhole scintigraph of the left knee in a 35-year-old woman with established rheumatoid arthritis shows intense, segmental tracer uptake in the tibial plateaus and lateral femoral condyle (arrows). Faint but significant tracer uptake can be seen also in the distal biceps femoris tendon, denoting concurrent tenosynovitis (arrowheads). These findings were validated by radiography (not shown here)

Fig. 10.6 Segmental or patchy tracer uptake in bone erosions and "faint" tracer uptake in tenosynovitis in rheumatoid arthritis. Anterior pinhole scintigraph of the left knee in a 35-year-old woman with established rheumatoid arthritis shows intense, segmental tracer uptake in the tibial plateaus and lateral femoral condyle (arrows). Faint but significant tracer uptake can be seen also in the distal biceps femoris tendon, denoting concurrent tenosynovitis (arrowheads). These findings were validated by radiography (not shown here)

Arthritis Joint Pain

Arthritis Joint Pain

Arthritis is a general term which is commonly associated with a number of painful conditions affecting the joints and bones. The term arthritis literally translates to joint inflammation.

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  • Temshe
    What is Periarticular tracer accumulation?
    2 years ago

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