Partial paralysis shows its self in various ways. It appeared very suddenly in my pullet and I thought she had broken a leg, as only one leg was affected at first. I tried to help it like you would a broken or spraddle leg but this led to the paralysis just getting worse. She would push to her feet, wobble back and forth, and then fall on her face. She would scream and flap her wings and I would run over and pick her up. It was really sad to see her in such poor condition.
Some of the hints that it was paralysis was her inability to pull her legs underneath her (she went to the side, behind, or in front of her), unable to control her feet, and having no other sign of disease (including a strong appetite).
Here she is. Her name was Amber, and she was such a sweet little bantam
When you held her she would stiffen her legs out but they would collapse when pressure was put under them
RIP Amber, I still miss you
Spittle was another chicken that suffered a similar issue. I'm not sure if it was spraddle leg or paralysis, however.
In an injury to the leg there shouldn't be signs of paralysis, but an injury to the back or head could cause nerve damage.