Relationship between bone density and osteoarthritis in a skeletal population from London.

To determine whether bone density was related to the presence of osteoarthritis in past populations, bone density was determined directly on bone slices taken from the fourth lumbar vertebra of a series of skeletons from a cemetery in London used from the middle 18th to the early 19th centuries. Eighty male and 57 female skeletons were studied and standard anthropological methods were used to determine age and gender. Osteoarthritis was diagnosed by the presence of eburnation on joint surfaces. The mean bone density in the males was 0.351 (+/-0.071) g/cm2, and in the females 0.332 (+/-0.091); this difference was statistically significant (p = 0.045). There was a significant, negative relationship with bone density and age in females (p = 0.0023), but not males (p = 0.073). Forty-seven of the males and 30 of the females had osteoarthritis, the most commonly affected joints being the facet joints of the spine and the hands. For the males there was no significant difference in bone density in those with or without osteoarthritis, but in females the bone density was significantly lower (p = 0.021) in those with osteoarthritis than in those without. The reasons why this result differs from modern populations in which patients with osteoarthritis tend to have higher bone density are discussed, and it is suggested that the most plausible explanation may relate to differences in nutritional status between past and modern populations.