Problem with admin Menu Structure layout

The main menu layout is messed up in the menu structure admin area.

I cannot make changes to the menu. Text is overlapping and the text fields are not opening to allow editing.

This is happening across all 3 of my wordpress sites and across all browsers.

I have different themes for each site so I doubt it is a template problem.

This problem has been around for months now and I have run out of things to try to resolve this issue.

Please help.

I have included a screen capture image below.

https://drive.google.com/file/d/0Bzzk_uRLSgdGVmNlbnR0cG5wZ2s/view?usp=sharing