Table 1 Stages of joint infection [5]
Gächter | The classification according to Gächter included IV Stages: |
|---|---|
Stage I | Opacity of fluid, redness of the synovial membrane, possible petechial bleeding, no radiological alterations. |
Stage II | Severe inflammation, fibrinous deposition, pus, no radiologic alterations. |
Stage III | Thickening of the synovial membrane, compartment formation ("sponge-like" arthroscopic view, especially in the suprapatellar pouch), no radiologic alterations. |
Stage IV | Aggressive pannus with infiltration of the cartilage, possibly undermining the cartilage, radiological signs of subchondral osteolysis, possible osseous erosions and cysts. |
Jensen | The classification according to Jensen included III stages: |
Stage I | Opaque effusion with high cell count, hyperaemia of the synovium. |
Stage II | Putrid effusion, fibrin coatings, synovial hypertrophy with petechial bleeding. |
Stage III | Severe villous synovitis with (partial) tamponade of the joint, synovial necrosis, synovial adhesions, cartilage destruction. |
Kuner | The classification according to Kuner was more a clinical description rather than an arthroscopic staging: |
Stage I | Purulent synovitis |
Stage II | Joint empyema |
Stage III | Panarthritis |
Stage IV | Chronic arthritis. |