We study some properties of integro splines. Using these properties, we design an algorithm to construct splines
$S_{m+1}(x)$
of neighbouring degrees to the given spline
$S_m(x)$
with degree m. A local integro-sextic spline is constructed with the proposed algorithm. The local integro splines work efficiently, that is, they have low computational complexity, and they are effective for use in real time. The construction of nonlocal integro splines usually leads to solving a system of linear equations with band matrices, which yields high computational costs.