[Radiologic observation of the blood supply changes around the knee with osteoarthritis].

OBJECTIVE: To compare blood supply changes around the knee joint between normal and osteoarthritis knee.

METHODS: From June 2014 to June 2015, 30 patients with knee osteoarthritis and 30 healthy adults were recruited. In osteoarthritis group, there were 9 males and 21 females, with a mean age of (65.967±7.132) years old(ranged, 53 to 82 years old), and the mean arterial pressure was(93.462±7.633) mmHg. In control group, there were 9 males and 21 females, with a mean age of (62.867±6.356) years old(ranged, 50 to 75 years old), and the mean arterial pressure was (92.122±9.675) mmHg. Inspection methods included color ultrasonic and computed tomography angiography of lower limbs. The patients were observed with: (1)collateral circulation; (2)artery circuity; (3)artery malformation; (4)artery stenosis; (5)arterial wall plaque formation. Stenosis was divided into 5 levels: level 1 as no narrow, level 2 as mild stenosis (1% to 49%), level 3 as moderate stenosis (50% to 70%), level 4 as severe stenosis (70% to 99%), level 5 as total obstruction. Diameter and blood flow dynamics of popliteal artery, pretibial artery, and posterior tibia artery in two groups were measured and compared.

RESULTS: The study was accomplished with complete data collection, none of the patients was eliminated, and there were no loss of follow up. There were 3 cases in OA group and 4 cases in control group with the formation of collateral circulation, and the difference had no statistically significance. There was none in OA group and 2 in control group with the formation of artery circuity, and the difference had no statistically significance. There were no cases in both groups with artery malformation. In OA group, there was mild in 14 cases, moderate in 7 cases, severe in 9 cases. In control group, there was no arterial stenosis in 9 cases, mild in 10 cases, moderate in 6 cases, severe in 4 cases, total obstruction in 1 case. The difference between two groups was statistically significant; artery stenosis in OA group was more severe than that of the control group. Artery plaque formed in 30 cases in OA group and in 20 cases in control group. The difference between two groups was statistically significant; the rate of artery plaque formation in OA group was obviously higher than that of control group. In OA group, plaque calcification rate was 100% while 63% in control group. Difference of pretibial artery diameter was statistically significant, pretibial artery diameter is larger in OA group. Difference of popliteal artery flow velocity was statistically significant; velocity was faster in OA group. Difference of the posterior tibial artery flow velocity was statistically significant; velocity was faster in OA group. The differences of the three arteries had no statistical significances in related to arterial flow.

CONCLUSIONS: Local artery system changes with the onset of knee joint osteoarthritis. Main pathological changesof local blood vessels were stenosis and plaque formation, but the amount of local artery blood flow was roughly the same as the control group. Possible mechanism is that the local artery stenosis speed up the artery blood flow velocity, resulting local perfusion. The local tissue ischemia and hypoxia caused a series of pathological changes. It is better to improve local vascular lesions than to accelerate the blood flow velocity in clinical treatment. Further more, interventional therapy for vascular pathology will be a new trend of osteoarthritis treatment.