Anyone know of a way to fix a spline length?

I'm wondering if anyone has done any work with Splines and holding the length to a fixed value?  This assumes that the endpoints could not get any further apart than a straight line, but as the ends got closer together (by way of some other constraints) the spline would "buckle" (for lack of a better term) to mimic the behavior of a semi rigid component (like a hose).