  We study the structure of the stable category
$\mathsf{\underline{CM}}^{\mathbb Z}(S/(f))$ of graded maximal Cohen-Macaulay
module over $S/(f)$ where $S$ is a graded ($\pm 1$)-skew polynomial algebra in
$n$ variables of degree 1, and $f =x_1^2 + \cdots +x_n^2$. If $S$ is
commutative, then the structure of $\mathsf{\underline{CM}}^{\mathbb Z}(S/(f))$
is well-known by Kn\"orrer's periodicity theorem. In this paper, we prove that
if $n\leq 5$, then the structure of $\mathsf{\underline{CM}}^{\mathbb
Z}(S/(f))$ is determined by the number of irreducible components of the point
scheme of $S$ which are isomorphic to ${\mathbb P}^1$.
