Multi Site Navigation Menu

Hi

Running into a challenge. I run a multisite network with dozens of subdomain sites. Running into a major problem when I have to modify the navigation menu on the master template and it has to propagate across the sub-domain sites.

Is there a way to a) set up the navigation menu so that it runs similar to an include and b) or is there a plugin that can manage the changes across the network.

Thank you

Andros