Figure 1.

Stimulation of calcium 45 (⁴⁵Ca) release from neonatal mouse calvarial bones by synovial fluids (SFs) from patients with osteoarthritis (OA) and patients with a loose prosthesis, but not by SFs from healthy individuals. (a) The effect of SFs from 25 patients with OA and 31 patients with a loose prosthesis. SF from each individual was added to bone culture medium (10%), and each sample was added to five or six bone cultures and incubated for 120 hours. The percentage release of ⁴⁵Ca induced by the different SFs was compared to that observed in unstimulated control bones (100%). Filled circles represent the mean of the effect on ⁴⁵Ca release caused by SF from the individual samples. The effect was statistically different (p < 0.05) in 3 of 31 samples from patients with a loose prosthesis and in 25 of 25 samples from patients with OA. (b) The concentration-dependent effect on ⁴⁵Ca release by SFs from patients with OA and patients with a loose prosthesis. The data are based on 12 different experiments (SFs from 6 patients with OA and 6 with a loose prosthesis) in which SFs from each patient in each category were incubated as described in (a) for 120 hours with five or six calvarial bones and the degree of stimulation was compared to unstimulated bones (100%). Data shown are the cumulative data for six patient samples in each category, and standard error of the mean (SEM) is shown as vertical bars. (c) The data from a comparison between SFs (1%) from patients with OA, patients with a loose prosthesis, and healthy subjects. Each sample was incubated for 120 hours with six or seven bones, and ⁴⁵Ca release was compared to unstimulated controls (100%). Values are expressed as mean ± SEM. Asterisks denote statistically significant stimulation (p < 0.01).