What was the purpose of the arm cast?
The mission commander injures her arm when the stowaway falls on her and she wears the arm cast throughout the movie, but this is never relevant to the plot. So from a narrative perspective, what was the purpose of giving her an injury and why couldn't the stowaway just drop down without falling onto her? Why does the plot require that she wears the cast?
Was it just to show how a 3D printer onboard the ship can print the cast?