If Jackson were playing today, that period immediately following his injury is when modern medicine could have possibly prolonged his career. Not even necessarily by wiping out the AVN or by catching it early, but by ensuring it never happened in the first place.
Prevention is the first line of defense here. MRIs and angiographs—injections of dye into the vessels followed by X-rays that visualize flow patterns—can demonstrate damage to vital blood vessels before extensive cell death occurs. The last 20 years has seen great strides in imaging quality, allowing analysis of fine structural integrity, and we know about the best timing, types, and views to implement for specific injuries. Immediate X-rays, CTs, and MRIs are necessary for visualizing dislocations or bleeding into the joint, but aren't effective in visualizing AVN until four or six weeks post-injury.3