Calcium-acidic phospholipid-phosphate complexes in diseased and normal human bone.

Ca-acidic phospholipid-PO4 complexes promote in vitro hydroxyapatite nucleation and/or growth and are believed to have similar functions in vivo. The complexed acidic phospholipid content of human bones has been studied in femoral heads obtained at surgery from patients with osteonecrosis and osteoarthritis and compared with age-matched, disease-free control bones. The content of Ca-acidic phospholipid-PO4 complexes was elevated in bones that were judged on the basis of radiographic and histological data to be actively making new bone. These data suggest that the relative concentration of Ca-acidic phospholipid-PO4 in bone may be related to the rate at which bone is being made and mineralized.