Which part of the blood in the knee joint is responsible for its detrimental effects? (An experimental study on the knee joint in rabbits)

Abstract

Aim This study aims to determine the potential causative elements which are responsible for the cartilage damage in case of frequent intra‐articular bleeding and to evaluate the effects of intra‐articular free iron and chelation of iron in the knee joint. Methods Thirty‐five New Zealand rabbits were randomly divided into five groups according to substances injected into their knee joints. Plasma (group I) and cellular components (group II) of the blood harvested from the rabbits, iron (ferric hydroxide sucrose) (group III), iron&chelator (group IV) and only chelator (deferoxamine mesylate) (group V) were injected into their right knees three times a week for 12 weeks. The joint surface was examined histologically according to the classification system modified from Colombo et al. The changes in the synovial tissue were evaluated according to the scoring system modified from Madhok et al. Results Cartilage and synovial abnormality scores were significantly higher in all study groups when compared to their own controls (p < 0.0001). Cartilage scores of groups I and V were significantly lower when compared to groups III and IV (p = 0.002 for group I and p = 0.003 for group V). Synovial abnormality score of group I was significantly lower than scores of groups III and IV (p = 0.001); and of group V lower than groups III and IV (p = 0.003 and p = 0.001, respectively). Conclusions All substances tested in this study caused a certain amount of damage in the cartilage tissue and led to synovial abnormalities. Both iron and iron&chelator caused more damage in the cartilage and led to more advanced synovial changes when compared to the plasma component of blood and chelator itself. Influence of iron and iron&chelators were found to be similar showing that chelation was inadequate in antagonizing the detrimental effects of iron.

The detrimental effects of iron to the joint; aggravation by inflammation

“…(An experimental study on the knee joint in rabbits)' which was recently published in Haemophilia. 1 Colak et al investigated the influence of different blood components on joint damage by injecting them separately into a rabbit knee. They found the most profound joint changes upon iron injections compared to plasma or the cellular components of autologous blood.…”

Towards Personalized Treatment in Haemophilia: The Role of Genetic Factors in Iron and Heme Control to Identify Patients at Risk for Haemophilic Arthropathy

“…Iron has a pivotal role in the pathogenesis of HA [12][13][14]. Upon a joint bleed, hemederived iron accumulates as hemosiderin within the synovium, where it induces inflammation and cell proliferation, causing chronic synovitis and synovial hyperplasia [15][16][17].…”