Is there a way to bind just the selected index of an igCombo to a knockout observable? I don't want to bind the data itself or anything else.

Something like:

 <span id="usersettings_initialtab_input" class="inputselectlist"
       data-bind="igCombo: { selectedIndex: navigationTab}">
</span>

That doesn't work, but that's the idea of what I'm trying to achieve, where navigationTab is a knockout observable in my viewmodel.