los nudillos

Tenía los nudillos blancos de apretar tan fuerte el volante.

His knuckles were white from gripping the steering wheel so tightly.

Nudillos.

Knuckles.

— Paddington 2 (2017)

Nudillos, volviste.

Knuckles, you're back.

— Paddington 2 (2017)

Come, o te daré un sándwich de nudillos.

Eat, or I'll give you a knuckle sandwich.

— Los falsificadores (2007)

Digamos que tendré que darle en los nudillos.

Let's just say I'll have to hit him in the knuckles.

— Perdición (1944)