Can you please explain me why do we do type 3 thyroplasty in puberophonia?

Can you please explain me why do we do type 3 thyroplasty in puberophonia?

Vocal cord shortening leads to high pitch voice and here in puberophonia the male already has a high pitch voice. Shouldn’t we lengthen vocal cords to make it low pitch?

I hope the drawing will be helpful

in your diagram shortening of length between anterior commissure and posterior commissure .

In shortening we are not cutting the vocal cord short but we are compressing it anteroposteriorly so that it becomes short but also lax . Hence Reducing the tension by making vocal cord lax produces a low pitch voice

thanks ma’am