The physiology of bone blood flow: a review.
BACKGROUND
Bone circulation plays an important role in bone physiology, but has been relatively poorly studied, because most techniques of circulatory research are difficult to apply to bone. This article summarizes briefly some of the important aspects of the physiology of bone blood flow most relevant to orthopaedics.


METHODS
The gold standard for experimental measurement of bone blood flow is the radioactive microsphere technique, though advances are being made in other techniques, such as positron emission tomography, laser and ultra-sound Doppler velocimetry, and near infrared spectroscopy, that may provide useful clinical measurement in the future.


RESULTS
Multiple vascular pathways contribute to an adaptive response to traumatic disruption of bone circulation. The microcirculation is not merely a passive conduit for blood flow, but plays an active role in controlling bone processes such as osteochondral ossification.


CONCLUSIONS
The pathophysiology of bone circulation has been associated with osteonecrosis, but more and more evidence is pointing to the importance of bone circulation in fracture repair and osteoporosis, both of which are potentially very exciting areas for future studies.
McCarthy
Ian
I
Institute of Orthopaedics and Musculoskeletal Science, Royal National Orthopaedic Hospital, Brockley Hill, Stanmore HA7 4LP United Kingdom. i.mccarthy@ucl.ac.uk
D001842:Bone and Bones / Q000098:blood supply* / Q000503:physiopathology; D050723:Fractures, Bone / Q000503:physiopathology; D006801:Humans; D010020:Osteonecrosis / Q000503:physiopathology; D010024:Osteoporosis / Q000503:physiopathology; D012039:Regional Blood Flow / Q000502:physiology