Hemodynamics of the Juvenile Knee in Relation to Increasing Intra-Articular Pressure: An Experimental Study in Dogs

Abstract

The relationships between intraosseous pressure and regional blood flow in the juxta-articular epiphyses were determined in the knees of immature dogs. Intraosseous pressures were continuously registered in one knee. Regional blood flow rates were simultaneously determined by the microsphere technique before and after venous tamponade of both knee joint capsules. During complete venous tamponade the intraosseous pressure of the distal femoral epiphyses rose 268%, while flow increased 122%. A concurrent 20-fold flow increase of the knee capsule and 3-4-fold flow increase of the proximal femoral bone was observed. Evacuation of the knee joints resulted in an immediate drop of the intraosseous pressure of the distal femoral epiphyses, whereas hyperaemia prevailed for at least half an hour and was most pronounced in the distal femoral epiphyses and knee joint capsule. Intraosseous pressure registration did not significantly influence regional blood flow. It is suggested that the changes of intraosseous pressures during knee joint tamponade reflect changes in the venous outlet resistance. The results demonstrate the significance of intra-articular pressure increase on the hemodynamics of the juxta-articular tissues of the knee and proximal femoral bone. These findings may be of importance in the pathogenesis of growth disturbances observed in juvenile degenerative arthritis.

Blood Flow in the Juvenile Hip in Relation to Changes of the Intraarticular Pressure: An Experimental Investigation in Dogs

“…This did not alter the flow in the femoral head as compared to the control side. Neither did the cannulation of acetabulum cause any significant flow increase in this bone, which is in accordance with other studies (Bouteiller et al 1979, Bunger et al 1982. On the other hand the cannulation and the following flushing of the joint resulted in a significant flow increase in the hip joint capsule, which had presumably been even higher after dissection and puncture.…”

Effect of increased knee joint pressure on oxygen tension and blood flow in subchondral bone

“…The suggested fall in the blood flow as an explanation for the observed changes in the oxygen tension and the argon signal is in agreement with the results of Launders et al (1981), who found a 60% decrease in the regional blood flow of the canine femoral head after an increase in the hip joint pressure to 48 mmHg. However, in a recent study, Bunger et al (1983) provoked a very considerable increase in the regional blood flow of the juvenile canine epiphysis by increasing the knee joint pressure to 75 mmHg. The positive correlation between the intra-articular pressure and the regional blood flow was explained by neuro-humoral regulation of the vascular resistance, but this hypothesis was not supported by experimental data.…”

Microspheres Accurately Predict Regional Bone Blood Flow

“…Although other authors have pointed out that fewer spheres present in an individual sample still allow for detection of flow heterogeneity, 37,42,45 application of the 400 rule is more reliable to detect flow differences in single tissue samples. The results of other studies in which distinctly less than 1.0 × 10 6 microspheres per kg body weight 11,17,48 were injected, should be considered with caution.…”