The acute effects of blocking medullary blood supply on regional cortical blood flow in canine ribs as measured by the hydrogen washout technique

Regional cortical blood flow was measured in 23 adult mongrel dogs using the hydrogen washout technique. Cortical blood flow in the rib was found to be 4.7 ± 0.8 ml/min/100 ml (n = 21). The concept of a dual blood supply to cortical bone is supported since eliminating the medullary supply did not affect the measurable cortical blood flow in most of the animals. Under normal and pathological conditons, adjacent cortical areas within the same bone have different blood flow rates.