Why not use a 20lb sledgehammer? Cheap, quick, simple enough that a Shariah lawman can figure it out...
Bigger chance of doing more damage than the court decides is appropriate...
They are not necessarily unsophisticated, it's just on a different path than our own.
My reactions to the article -
1. It mentions a 'fight', personally I tend to associate that with
mutual combat, and in mutual combat I think that you should suffer what you suffer.
2. The victim is requesting this punishment, and as I understand their justice system, it places a LOT of weight on what the victim asks for.
If the man they're proposing doing this to was the attacker and the other man only defending himself, then I can understand. If it was a 'mutual' thing, then not so much. I still favor making the intact man work for supporting the crippled one, but who knows.