Evaluation blood supply via DCE-MRI
left idiopathic ONFH, ONFH, abnormal hyperperfusion, necrotic
NECROTIC

Group A: Patient Yan X, male, 29 years old, with left-sided hormonal ONFH. The patient’s hip was fixed with a biodegradable magnesium screw. More details are shown in Figs. IAUGC and Ktrans synthetic pseudo-colour images. At 6 months postoperatively, there was a significant reduction in abnormal hyperperfusion in the repaired area (green arrow) and a significant improvement in microcirculation in the necrotic area (white arrow) compared to the preoperative periodTime-intensity curve (TIC). The perfusion of necrotic area increased and peak of perfusion decreased in the repair area 6 months after surgery. This suggests an improvement in microcirculation in the necrotic area and a decrease in abnormal hyperperfusion in the repair response area. The microcirculatory perfusion in the necrotic and repaired areas gradually converged to normal bone tissueGroup B: Patient Lu XX, male, 21 years old, with bilateral hormonal ONFH. The patient underwent bilateral PVIBGT with magnesium screws. More details are shown in Figs. IAUGC and Ktrans synthetic pseudo-color images. Compared to the preoperative period, abnormal hyperperfusion in the repaired area was significantly reduced at 6 months postoperatively (green arrow), but microcirculation in the necrotic area was not as improved as in Fig. Time-intensity curve (TIC). The perfusion increased in necrotic area and peak of perfusion decreased in the repair area 6 months after surgery. A decrease in abnormal hyperperfusion in the repair-responsive area can be clearly observed in the figure, but the improvement in microcirculation in the necrotic area is less pronounced than in group A (Fig. Group C: Patient Peng XX, male, 33 years old, with left idiopathic ONFH. The patient underwent a left-sided PVIBGT without any screw. More details are shown in Figs. IAUGC and Ktrans synthetic pseudo-color images. Compared to the preoperative period, at 6 months postoperatively, there was a significant reduction in abnormal hyperperfusion in the repaired area (green arrow), but no significant improvement in microcirculation in the necrotic area (white arrow)Time-intensity curve (TIC). The perfusion increased in necrotic area and peak of perfusion decreased in repaired area 6 months after surgery. The tendency of microcirculation in the repair-responsive area to normal bone tissue can be clearly observed in the figure, but the improvement in microcirculation in the necrotic area is also less pronounced than in group A (Fig. 