What's the plural form of Holstein-Lewis fracture? Here's the word you're looking for.
Answer
The noun Holstein-Lewis fracture can be countable or uncountable.
In more general, commonly used, contexts, the plural form will also be Holstein-Lewis fracture.
However, in more specific contexts, the plural form can also be Holstein-Lewis fractures e.g. in reference to various types of Holstein-Lewis fractures
or a collection of Holstein-Lewis fractures.