Acute sickle cell disease

What is the pathophysiology of acute sickle cell disease (SCD) crisis? Why is pain the predominant feature of acute crises?

Sickle cell disease (SCD) occurs due to mutations in the β-globin gene. The result is the formation of deformed hemoglobin that triggers complications including the vaso-occlusive crisis, hemolysis, infections, pulmonary complications, and cardiovascular disease