I have that. For me it was brought on by kayaking. It got so bad I couldn't use my hand or even turn my wrist a tiny bit without excruciating pain.

For me, a thumb wih half wrist splint worked (half longitudinally). I had to wear it for months. I now wear a full rigid wrist/thumb splint for kayaking and the half wrist if I feel it flaring. The little pica splint did nothing.

I'd have the surgery if they'd offer it to me.