Subchondral PO2 and PCO2 are unaffected in experimental arthrosis

We have made comparative measurements of oxygen and carbon dioxide tensions in normal and osteoarthritic subchondral bone tissue of rabbits in the 4-month stage of unilateral experimental arthrosis of the knee. The gas tensions were measured by a mass spectrometer via a special catheter inlet system. The mean values of the oxygen tensions on the normal and the osteoarthritic side were 39.8 and 46.2 mmHg, respectively. The carbon dioxide tensions were 33.3 and 34.2 mmHg. Neither difference was significant.