Can you be more specific about where it is, or perhaps attach a screenshot of your map?

My memory is that at one point you might be able to throw something through the spears to hit a switch and open them. But there are definitely a few spots with spears blocking the path and it's quite possible that you just have to return later. It's been a while since I played.

This is the one and ONLY place with spear gate opened by throwing f.ex. dagger onto switch beyond the gate.