We previously published on the pressure effect using a rheumatoid animal model (Pain Physician in 2013 and 2014). However, we do not know how long the pressure effect lasts after exposure to high pressure. We evaluated the duration of the pressure effect in a day for a given study period. Laboratory animal study. Following injection of Complete Freund’s Adjuvant (CFA) into one side of the knee joint, 8 rats were assigned to 1.5 atmospheres absolute (ATA) hyperbaric chamber 3 hours per day for one or 2 weeks (1WPG or 2WPG). Pain levels were assessed daily for 2 weeks according to weight bearing force (WBF) of the affected limb. In addition, the levels of gelatinase, MMP-2, and MMP-9 expression in synovial fluids of the knees were analyzed.

Koo, Shin, Lee, Lee, , , , , (). The continuance time of pressure effect in the rat model of complete Freund’s adjuvant induced arthritis. Pain physician, ;18(1):E39-45. https://www.ncbi.nlm.nih.gov/pubmed/25675069