Distribution of bone mineral density with age and gender in the proximal tibia.

Abstract

To investigate both the age and gender related distributions of bone mineral density in the proximal tibia, specifically in aged patients. For surgeons to achieve stable long-term fixation of implants in the proximal tibia, the distribution of bone mineral density must first be known. The changes that occur due to age or gender can alter these distributions. Quantitative computed tomography and indentation testing were used to investigate 40 human tibiae (27 female, 13 male, average age 63.3 years). A significant reduction in bone mineral density was found in female tibiae between the age groups of < 60 and > or =60. This difference was not found in the male groups and no other significant difference was found between consecutive age groups. A three-dimensional map of the bone mineral density of the proximal tibia is therefore presented for the groups female < 60, female > or =60 and male. Reduced bone mineral density was consistently found in the central regions, whilst the regions of highest bone quality varied from postero-lateral to postero-medial. Implant fixation for fracture treatment as well as joint replacement of the proximal tibia are now able to take the regions of both high and low bone mineral density into consideration in older patients and those suffering from osteoporosis. Knowledge regarding the regional distribution of bone mineral density in the proximal tibia is necessary in order to achieve stable primary and long-term fixation of implants. This manuscript documents the bone mineral density changes that occur with age and gender.