Mark, Samantha's boyfriend, told TMZ the pair were driving near a toll booth when they had a "paparazzi confrontation". Trying to avoid a crash, he swerved the auto and hit a concrete barrier.
Samantha, who is battling MS, hit the windshield then fell to the floor with her leg twisted backward.
It comes as her father Thomas Markle reportedly acquired out of main cardiac surgical procedure after struggling a critical coronary heart assault final week.
The news comes after reports that Meghan's father, Thomas Markle, 73, will not be attending her and Prince Harry's wedding on Saturday in the United Kingdom due to health issues.
"She's way out of her league to tell me I can't speak", she told TMZ.
Samantha has been publicly vocal about her alleged experiences with her half-sister Meghan, since the announcement of the former Suits actress' engagement to Prince Harry.
Atletico Madrid wins third Europa League title
Meanwhile, authorities in Lyon are hoping the match, which will kick off at 8:45pm (1845 GMT), will not be marred by violence. Right-back Bouna Sarr has an issue with his shoulder but could be fit, with Hiroki Sakai likely to take his place if not.
Long awaited YouTube Music is finally coming
While I'm not interested in the new services, I'm sure that users from around the world will find the services interesting. You also won't be able to download music for offline listening on this tier either.
F1 Spanish GP digest: victory is a turning point for Lewis Hamilton
Vettel gave away his position when Ferrari chose to go for an extra stop and give the German driver fresher tyres. With Sunday's win, Hamilton opened up his lead over Vettel to 17-points in the overall standings.
Samantha didn't receive an invite to Prince Harry and Markle's royal wedding.
The Markle family can not catch a break. She insisted it was for the benefit of the royal family and not a cheap grab for cash.
She added that she would like to give the present to Markle personally.
Samantha then came forward to say the pictures had been her idea, as she wanted to show her father in a good light and counter previously unflattering paparazzi images.
Samantha and Meghan's father Thomas announced on Monday night he wouldn't be attending the wedding, after he was accused of working with a photography agency on staged paparazzi shots.
In just two days time Meghan Markle will walk down the aisle at Windsor Castle.