Knee arthroscopy and exercise versus exercise only for chronic patellofemoral pain syndrome: a randomized controlled trial.

Background: Arthroscopy is often used to treat patients with chronic patellofemoral pain syndrome (PFPS). As there is a lack of evidence, we conducted a randomized controlled trial to study the efficacy of arthroscopy in patients with chronic PFPS.

Methods: A total of 56 patients with chronic PFPS were randomized into two treatment groups: an arthroscopy group (N = 28), treated with knee arthroscopy and an 8-week home exercise program, and a control group (N = 28), treated with the 8-week home exercise program only.

High levels of expression of collagenase-3 (MMP-13) in pathological conditions associated with a foreign-body reaction.

A foreign-body-type host response can contribute to the induction and release of collagenolytic tissue-destructive enzymes of pathogenetic significance. Our aim was to analyse collagenase-3 in two conditions with putative involvement of foreign-body reactions. Synovial membrane-like tissue samples were obtained from cases of aseptic loosening of a total hip replacement (THR) and osteoarthritis (OA).