The cell density of human femoral head cartilage.

The human femoral head cartilage in 63 subjects with ages ranging from 16 to 100 years demonstrates that in the course of aging the cell density of the whole cartilage thickness decreases about 40 per cent. The reduction of the cellularity with age is more accentuated in the superficial than in the deeper zone and is even limited to the superficial zone during the latter part of aging. Proportionately the cell loss is similar in the superior and inferior poles of femoral head suggesting a uniform distribution of age related changes. In absolute value, the decrease of the superficial cell density is much higher in the inferior than in the superior pole; the decrease may be related to the propensity of this region to fibrillation.