Bone marrow circulation after osteotomy. Blood flow, pO2, pCO2, and pressure studied in dogs.

We investigated the immediate effect of osteotomy of the femoral shaft in adult dogs on intramedullary pO2, pCO2, relative bone blood flow (RBF) and intraosseous pressure (IOP). Single osteotomy resulted in a pO2 decrease from 49 mm Hg to 30 mm Hg. Double osteotomy further reduced pO2 to 21 mm Hg. Following double osteotomy, pCO2 increased from 42 mm Hg to 55 mm Hg. IOP was decreased by single osteotomy from 29 mm Hg to 15 mm Hg, and to 4 mm Hg by the second osteotomy. Linear regression analysis showed a negative correlation between pCO2 and RBF. We concluded that osteotomy introduces immediate haemodynamic and metabolic changes in the bone marrow canal. A periosteal supply of the endosteal bone seems possible provided this system is intact.