具有数学表达式和等号的 Mdframed 定理

Question

我怎样才能将“n = 3, \alpha = 0 且 $\alpha$ 存在”这样的内容作为 mdframed 命题的框架标题，例如

代码

\documentclass[a4paper,11pt]{scrreprt}
\usepackage{tikz}
\usepackage[framemethod=tikz]{mdframed}
\usetikzlibrary{calc}
\usepackage{ntheorem}

\newcounter{mydef}[chapter]
\renewcommand\themydef{\thechapter.\arabic{mydef}}

\makeatletter
    \def\mdf@mytitle{}
    \define@key{mdf}{mytitle}{%
      \def\mdf@mytitle{#1}}

    \mdf@do@stringoption{digressiontitle=={Digression}}

    \tikzset{
    excursus line/.style={%
    line width=2pt,
draw=gray!40,
rounded corners=2ex,
},
excursus head/.style={%
fill=white,
font=\bfseries\sffamily,
text=blue!80,
anchor=base west,
},
}
\mdfdefinestyle{digressionarrows}{%
singleextra={%
\path let \p1=(P), \p2=(O) in (\x2,\y1) coordinate (Q);
\path let \p1=(Q), \p2=(O) in (\x1,{(\y1-\y2)/2}) coordinate (M);
\path [excursus line]
($(O)+(5em,0ex)$) -| (M) |- %
($(Q)+(30em,0ex)$);
%\node at ($(M)$) {M};
%\node [excursus head] at ($(Q)+(2.5em,-0.75pt)$) {Digression};},
\ifx\empty\mdf@mytitle\empty
   \node [excursus head] at ($(Q)+(2.5em,-0.75pt)$) {\mdf@digressiontitle~\themydef};
\else
   \node [excursus head] at ($(Q)+(2.5em,-0.75pt)$) {\mdf@digressiontitle~\themydef:\space\mdf@mytitle};
\fi},
firstextra={%
\path let \p1=(P), \p2=(O) in (\x2,\y1) coordinate (Q);
\path [excursus arrow,-to]
(O) |- %
($(Q)+(12em,0ex)$) .. controls +(0:16em) and +(185:6em) .. %
++(23em,2ex);
%\node [excursus head] at ($(Q)+(2.5em,-2pt)$) {Digression};},
\ifx\empty\mdf@mytitle\empty
   \node [excursus head] at ($(Q)+(2.5em,-0.75pt)$) {\mdf@digressiontitle~\themydef};
\else
   \node [excursus head] at ($(Q)+(2.5em,-0.75pt)$) {\mdf@digressiontitle~\themydef:\space\mdf@mytitle};
\fi},
secondextra={%
\path let \p1=(P), \p2=(O) in (\x2,\y1) coordinate (Q);
\path [excursus arrow,round cap-]
($(O)+(5em,0ex)$) -| (Q);},
middleextra={%
\path let \p1=(P), \p2=(O) in (\x2,\y1) coordinate (Q);
\path [excursus arrow]
(O) -- (Q);},
middlelinewidth=2.5em,middlelinecolor=white,
hidealllines=true,topline=true,
innertopmargin=0.5ex,
innerbottommargin=2.5ex,
innerrightmargin=2pt,
innerleftmargin=2ex,
skipabove=0.87\baselineskip,
skipbelow=0.62\baselineskip,
}
\makeatother

\newmdenv[style=digressionarrows, settings = \refstepcounter{mydef}, digressiontitle=Definition]{df}
\newmdenv[style=digressionarrows, settings = \refstepcounter{mydef}, digressiontitle=Proposition]{prop}


\begin{document}

\chapter{Chapter}
\section{test}

\begin{df}[mytitle = Pythagoraen Theorem $a = 5, \alpha = 0$ with $\alpha$ is there]
test text
\label{pythag}
\end{df}

In the pythagoraen theorem there are $a,b$ and $c$ such that $a^2+b^2 = c^2$ (see \ref{pythag}).

\begin{df}
test text.
\end{df}

\begin{prop}
    blablab.
    \label{propbla}
\end{prop}

In proposition \ref{propbla} there are things.

\end{document}