Psoriatic and reactive arthritis

–Erosive and productive change (also seen in erosive OA)

–Erosions have fuzzy margins and wisps of periostitis

–Distal predominance and soft tissue swelling

–In late phases, ankylosis of joints may occur

–Another feature is sausage digit type soft tissue swelling

–Very late, arthritis mutilans, with resorption of phalanges

–Pencil-in-cup deformity may result

–Bone density usually normal except for juxta-articular osteoporosis

–acroosteolysis is another possible feature

Although there is overlap, as a general rule, psoriatic favors hands and reactive the foot

Reactive arthritis

–Urethritis (85%)

–Conjunctivitis (60%)

–Arthritis (> 60%)

–Young adults, M:F > 5:1

Joint Space narrowing