Cartilage surface erosion in four condyles in 5-month-old (a) and 7-month-old (b) female rats maintained for 9 weeks after ovariectomy or a sham operation. The erosion (expressed as percentage of total cartilage surface) is presented as mean erosion + SEM for the two groups (OVX and sham-operated). Mean scores are represented for each of the four condyles – medial tibia (Medial T), medial femur (Medial F), lateral tibia (Lateral T), and lateral femur (Lateral F) – and for all four taken as a group (Total). P values indicate difference between ovariectomized (OVX) and sham-operated rats assessed using the nonparametric Mann–Whitney U test.
Høegh-Andersen et al. Arthritis Res Ther 2004 6:R169-R180 doi:10.1186/ar1152