Effect of Non-Steroidal Anti-Inflammatory Drugs on Osteoarthritis of the Knee: With Special Reference to PSP Clearance as an Indicator.

PSP clearance of the osteoarthritic knee was studied in 79 joints of 60 patients. Correlation between the clearance rate and the degree of disease activity (the grade of inflammatory exacerbation) was suggestive. Using PSP clearance, we studied the effect of non-steroidal anti-inflammatory drugs on the osteoarthritic knee. The results of this study are as follows: The drugs, phenylbutazone, indomethacin and acetyl-salicylic acid, are effective, when they are administered at the initial phase of inflammation, while in the chronic phase the effects of them are variable, though significant in patients whose PSP clearance rate is below 45 per cent. In the chronic and severely affected cases, the basic principles of therapy of osteoarthritic knees are avoidance of excessive use and the correct use of rest and physical therapy.