[Experimental studies on the effective factors and the neural control system of intraosseous pressure in the patella of dogs].

Physiological studies on the patellar intraosseous pressure gave the following results: The mean value of the intraosseous pressure was 12.5 mmHg (range 7-19.5 mmHg). The effects of femoral vascular occlusion and intravenous infusion of epinephrine or norepinephrine were similar to those reported on long bones. Not only the elevation of intraarticular pressure but also the compression of the infrapatellar fat pad increased intraosseous pressure during extension or flexion of the knee as a result of venous engorgement. The results of efferent nerve stimulation suggested that the femoral nerve carried the vasomotor fibers supplying the vessels of the patellar bone marrow. The afferent nerve responded to more than 20-39 mmHg elevation of the patellar intraosseous pressure.