[Surgical pathology of revision after knee and hip arthroplasty]

To investigate clinical characteristics and pathological changes of tissue surrounding prosthesis after hip and knee arthroplasty.

A total of 67 patients receiving hip and knee arthroplasty were included in the study and pathological changes of the revision specimens were evaluated by microscopic examination.

Of 67 patients, there were 25 males and 42 females (ratio of 0.6) with a mean age of 64 years. There were 42 cases of revision hip prosthesis and 25 cases of knee prosthesis. The primary causes for the revision varied, including 20 cases of infection (29.9%, within 3 months in 9 cases,3 to 24 months in 3 cases and over 24 months in 8 cases), 14 cases of pain (20.9%), 13 cases of loosening of the prosthesis (19:4%), 9 cases of joint stiffness (13.4%), 8 cases of prosthetic dislocation (11.9%), and 3 cases of prosthesis fracture (4.5%). Pathological findings in the tissue surrounding the prostheses included debris reaction, histiocytes, acute inflammatory, chronic non-specific inflammation, pigmented villonodular synovitis (PVNS), "pseudomembranous", calcification, necrosis, sequestrum, etc. These histological changes were frequently admixed.

Various reasons may lead to hip and knee revision arthroplasty. The main pathological findings include infection, debris granulomas, chronic non-specific inflammatory changes, PVNS. The surgical pathology of the prosthesis provids guidances for clinical treatment and basic research.